Neck of Femur Fracture in Adults

SECTION 1: Clinical Overview

1.1 Summary

A neck of femur (NOF) fracture, commonly referred to as a hip fracture, is a critical orthopedic injury involving the proximal femur between the femoral head and the trochanteric line. This condition represents a global public health crisis, primarily affecting the elderly population with underlying osteoporosis, though it can occur in younger patients following high-energy trauma. The epidemiological context is stark: approximately 1.6 million hip fractures occur worldwide annually, a figure projected to rise to 6 million by 2050 due to demographic aging. [1]

Classification is fundamentally divided into intracapsular (within the joint capsule) and extracapsular (intertrochanteric or subtrochanteric) fractures—a distinction that dictates management due to the unique and precarious blood supply of the femoral head. [2] Intracapsular fractures are further classified using the Garden classification (Stages I-IV), which correlates with risk of avascular necrosis (AVN) and guides surgical decision-making between internal fixation and arthroplasty. [3]

Clinical significance cannot be overstated: NOF fractures are associated with a 30-day mortality rate of 8-10% and a 1-year mortality rate approaching 30%, making this injury more lethal than many common malignancies. [4] Management is almost exclusively surgical, with national guidelines mandating surgery within 36-48 hours of admission to reduce mortality, complications, and hospital length of stay. [5] The timing of surgery is critical: meta-analyses demonstrate that delays beyond 48 hours are associated with significantly increased mortality (OR 1.41, 95% CI 1.29-1.54). [6]

The standard of care involves a multidisciplinary orthogeriatric co-management model, integrating surgical fixation or arthroplasty with comprehensive medical optimization, early mobilization, osteoporosis management, and falls prevention. [7] Evidence from randomized controlled trials demonstrates that this collaborative approach reduces mortality, length of stay, and institutional care requirements. [8]

Surgical decision-making is complex and individualized. For displaced intracapsular fractures in the elderly, the choice between hemiarthroplasty and total hip arthroplasty (THA) depends on pre-morbid mobility and cognitive function. [9] For extracapsular fractures, dynamic hip screw (DHS) remains the gold standard for stable intertrochanteric fractures, while intramedullary nailing is preferred for unstable patterns and subtrochanteric extension. [10]

Prognosis depends heavily on pre-morbid functional status, comorbidity burden (ASA grade), the timeliness of surgery, and the quality of post-operative rehabilitation. Only 50% of survivors regain their pre-fracture level of independence, with many requiring permanent institutional care. [11] Secondary prevention of osteoporotic fractures through bisphosphonate therapy is essential but remains tragically underutilized, with treatment gaps exceeding 70% in many healthcare systems. [12]

This topic file provides a comprehensive, evidence-based review of the anatomy, pathophysiology, classification systems (Garden, AO/OTA), investigation algorithms, surgical management principles, complication management, and long-term outcomes of NOF fractures in the adult population.

1.2 Key Facts

• Definition: A fracture of the proximal femur involving the femoral neck (intracapsular), intertrochanteric region, or subtrochanteric region (extracapsular).
• Incidence: Approximately 70,000-75,000 cases per year in the United Kingdom; 300,000+ in the USA; 1.6 million globally. [1]
• Prevalence: Lifetime risk is approximately 17% for women and 6% for men in Western populations.
• Mortality: 30-day mortality 8-10%; 1-year mortality 20-30%; higher in males and those with delayed surgery. [4]
• Morbidity: 50% of survivors do not regain pre-fracture mobility; 20-25% require permanent institutional care. [11]
• Peak Age: 80-85 years; incidence doubles every 5-10 years after age 50.
• Sex Distribution: Female-to-Male ratio approximately 3:1 in elderly populations (osteoporosis-related); 1:1 in high-energy trauma.
• Pathognomonic Feature: Shortened, externally rotated leg in patient unable to bear weight (classic for displaced fractures).
• Gold Standard Investigation: Plain radiography (AP pelvis + lateral hip); MRI for occult fractures (sensitivity 99%, specificity 99%).
• First-line Treatment: Surgical fixation or arthroplasty within 36-48 hours (NICE/AAOS guideline). [5]
• Surgery Timing Target: less than 48 hours reduces mortality by 19% (OR 0.81, 95% CI 0.68-0.96). [6]
• Key Surgical Decisions:
  • "Displaced intracapsular: Arthroplasty (hemiarthroplasty vs THA based on mobility/cognition). [9]"
  • "Undisplaced intracapsular: Internal fixation (cannulated screws or DHS). [13]"
  • "Extracapsular stable: Dynamic Hip Screw (DHS). [10]"
  • "Extracapsular unstable/subtrochanteric: Intramedullary nail (cephalomedullary nail). [10]"
• VTE Prophylaxis: Mandatory mechanical (TED stockings/intermittent pneumatic compression) + pharmacological (LMWH or DOACs) for minimum 28-35 days. [14]
• Key Complication: Avascular necrosis (AVN) of femoral head—10-30% in displaced intracapsular fractures; correlates with Garden stage. [15]
• Secondary Prevention: Bisphosphonate therapy reduces subsequent fracture risk by 40-50% but is initiated in less than 30% of patients. [12]

1.3 Clinical Pearls

Diagnostic Pearl: "The Occult Fracture Trap" Up to 10% of hip fractures may not be visible on initial plain X-rays. If a patient has a high clinical suspicion (pain on axial loading or log roll) but negative X-rays, they MUST have an MRI or CT within 24 hours. Do not discharge a patient who cannot walk without definitive imaging.

Examination Pearl: "The Log Roll Test" Passive internal and external rotation of the extended leg (the log roll) is the most sensitive physical examination maneuver. Pain elicited during this movement is highly suggestive of an intra-articular process or fracture, as it creates shear stress across the femoral neck.

Treatment Pearl: "The 36-Hour Rule" Mortality increases significantly when surgery is delayed beyond 36-48 hours. Pre-operative optimization should be "parallel" rather than "serial"—do not wait for every minor lab abnormality to be corrected before proceeding to theatre.

Pitfall Warning: "Ignoring the 'Why'" Never treat the fracture in isolation. Always investigate why the patient fell. A hip fracture is often the final symptom of an underlying medical crisis, such as a myocardial infarction, pulmonary embolism, or electrolyte derangement.

Mnemonic: "The 5 S's of Hip Fracture Presentation" Shortening of the limb, Sideways rotation (External), Severe pain in the groin, Standing/Weight-bearing impossible, Sudden onset post-fall.

Emergency Pearl: "Fascia Iliaca Block" Administer a Fascia Iliaca Compartment Block (FICB) as soon as possible in the ED. It provides superior analgesia compared to systemic opioids, reduces the risk of delirium, and facilitates better positioning for X-rays.

Exam Pearl: "Garden Classification" Examiners frequently ask about the Garden Classification for intracapsular fractures. Remember: Garden I (Incomplete/Impacted), II (Complete/Undisplaced), III (Complete/Partially Displaced), IV (Complete/Fully Displaced). It determines the risk of AVN.

1.4 Why This Matters Clinically

Patient outcomes are profoundly impacted by the speed and quality of the orthopedic response. A missed or delayed diagnosis of a hip fracture leads to rapid physiological decline; the "death spiral" of a hip fracture involves pain-induced delirium, dehydration, pressure ulcers, and hypostatic pneumonia. Within 48 hours of immobility, the risk of deep vein thrombosis (DVT) increases fourfold.

Healthcare burden is immense, with hip fractures consuming more hospital bed days than any other traumatic injury. In the UK, the annual cost to the NHS and social care is estimated at over £2 billion. Medico-legal scenarios often involve the failure to diagnose occult fractures or delays in surgery that result in avoidable mortality. Training relevance is high because this is a "bread and butter" condition for orthopedic surgeons, geriatricians, and emergency physicians, frequently appearing in postgraduate exams like the MRCS, FRCS, and MRCP.

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SECTION 2: Epidemiology

2.1 Incidence & Prevalence

• Incidence: 75-100 per 100,000 per year in developed nations [PMID: 29141757].
• Prevalence: Current global prevalence is estimated at 18 million cases; expected to triple by 2050.
• Lifetime Risk: 1 in 6 women will suffer a hip fracture; 1 in 15-20 men.
• Trend: Age-adjusted incidence is stable or slightly decreasing in the West, but total numbers are rising due to demographics.
• Geographic Variation: Highest in Scandinavia and North America; lowest in Africa and parts of Asia (the "Latitude Effect").
• Temporal Patterns: Significant increase in winter months due to icy conditions and vitamin D deficiency.
• Healthcare Burden: Average hospital stay is 15-20 days; accounts for 20% of all orthopedic bed occupancy.

2.2 Demographics Table

2.3 Risk Factors Tables

Non-Modifiable Risk Factors:

Modifiable Risk Factors:

2.4 Protective Factors

• Weight-bearing exercise: RR 0.6, increases bone mineral density and improves balance.
• Bisphosphonate therapy: RR 0.5-0.7, reduces osteoclast activity in diagnosed osteoporosis.
• Hormone Replacement Therapy (HRT): RR 0.7, prevents post-menopausal bone loss (though use is limited by SEs).

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SECTION 3: Pathophysiology

3.1 Step 1: Initiating Event and Mechanical Failure

The primary trigger for a NOF fracture in the elderly is usually a low-energy fall from standing height, typically with a direct impact on the greater trochanter. In younger patients, high-energy axial loading (e.g., motor vehicle accidents) is the cause.

At the molecular level, the initiation involves the failure of the trabecular bone in the femoral neck. In an osteoporotic state, there is an imbalance in the RANK/RANKL/OPG pathway. Increased RANKL (Receptor Activator of Nuclear Factor Kappa-B Ligand) expression by osteoblasts and T-cells binds to RANK receptors on osteoclast precursors, stimulating massive osteoclastogenesis. This leads to the resorption of the primary and secondary compressive trabeculae (Ward’s triangle), creating a zone of weakness. When the mechanical stress of a fall exceeds the ultimate tensile strength of the thinned cortex, a fracture propagates.

3.2 Step 2: Vascular Disruption and Ischemia

The femoral head has a precarious blood supply, primarily derived from the medial circumflex femoral artery (MCFA), which forms an extracapsular arterial ring. From this ring, retinacular vessels (superior, inferior, and anterior) penetrate the capsule to reach the head.

In an intracapsular fracture, especially if displaced (Garden III or IV), these retinacular vessels are often torn or kinked. The ligamentum teres artery provides only 5-15% of the blood supply in adults and is insufficient to maintain viability. The resulting ischemia triggers a cellular crisis within the osteocytes of the femoral head. Within 6-12 hours of total ischemia, osteocyte death begins, initiating the cascade toward avascular necrosis (AVN).

3.3 Step 3: Intra-capsular Tamponade and Hematoma

Following the fracture, a hematoma forms within the joint capsule. Because the hip capsule is relatively inelastic, the accumulation of blood increases intra-articular pressure. If this pressure exceeds the capillary perfusion pressure of the remaining intact retinacular vessels, a "tamponade effect" occurs, further exacerbating the ischemia of the femoral head.

Pro-inflammatory cytokines (IL-1, IL-6, TNF-α) are released from the fracture site. These cytokines recruit neutrophils and macrophages. In the intracapsular environment, there is a lack of a cambium layer in the periosteum, meaning that healing must occur via endosteal callus formation rather than the more robust peripheral callus seen in extracapsular fractures. This inherent biological limitation makes intracapsular fractures prone to non-union.

3.4 Step 4: Systemic Inflammatory Response and Metabolic Crisis

The fracture is not merely a local event; it triggers a Systemic Inflammatory Response Syndrome (SIRS). The release of damage-associated molecular patterns (DAMPs) into the circulation activates the innate immune system. This leads to:

1. Hypercoagulability: Activation of the coagulation cascade and suppression of fibrinolysis, increasing DVT risk.
2. Catabolic State: Massive release of cortisol and catecholamines, leading to hyperglycemia and muscle wasting (sarcopenia).
3. Fat Embolism: Micro-fragments of marrow fat may enter the venous circulation, potentially causing subclinical or clinical Fat Embolism Syndrome (FES).

3.5 Step 5: The Healing Cascade or Failure

In successful healing (usually after internal fixation), a primary bone healing process occurs where cutting cones of osteoclasts cross the fracture line, followed by osteoblasts laying down new lamellar bone.

However, in many cases, failure occurs:

• Non-union: Occurs if the mechanical stability is insufficient or the biology is poor (smoking, diabetes).
• Avascular Necrosis (AVN): If the blood supply does not return, the femoral head undergoes "creeping substitution." The dead bone is resorbed, but the new bone is structurally weak, leading to subchondral collapse and secondary osteoarthritis.
• Malunion: Resulting in a shortened, varus deformity that significantly impairs gait mechanics (Trendelenburg gait).

3.6 Classification Systems

Garden Classification (Intracapsular Fractures)

The Garden classification, introduced in 1961, remains the most widely used system for intracapsular femoral neck fractures despite known inter-observer reliability limitations. [3] It correlates fracture displacement with risk of AVN and guides treatment decisions. The classification is based on the degree of displacement and alignment of the trabecular pattern on AP radiographs.

Clinical Application: In practice, the Garden classification is often simplified into undisplaced (I/II) versus displaced (III/IV) fractures, as this distinction primarily drives surgical decision-making. Displaced fractures in elderly patients (> 65 years) are typically treated with arthroplasty due to high AVN risk, whereas undisplaced fractures may be treated with internal fixation if surgery is performed promptly. [3]

Limitations: Inter-observer agreement is moderate (κ = 0.4-0.6). Garden I and II fractures can displace secondarily (10-15%), necessitating protected weight-bearing and close radiographic surveillance. [3]

AO/OTA Classification (Comprehensive)

The AO/OTA classification provides a more detailed anatomical description applicable to all proximal femur fractures:

• 31-A: Extracapsular trochanteric fractures
  • "A1: Simple two-part pertrochanteric"
  • "A2: Multi-fragmentary pertrochanteric"
  • "A3: Reverse oblique/transverse intertrochanteric"
• 31-B: Intracapsular femoral neck fractures
  • "B1: Subcapital with minimal displacement"
  • "B2: Transcervical"
  • "B3: Displaced subcapital or non-union"
• 31-C: Femoral head fractures (rare)

Pauwels Classification (Biomechanical)

The Pauwels classification categorizes intracapsular fractures based on the angle of the fracture line to the horizontal, which predicts shear force and fixation stability:

• Type I: less than 30° angle—predominant compressive forces, favorable for fixation.
• Type II: 30-50° angle—mixed compressive and shear forces.
• Type III: > 50° angle—predominant shear forces, high risk of fixation failure; favors arthroplasty.

Higher Pauwels angles correlate with increased re-operation rates after internal fixation (Type III: 30% failure vs. Type I: 5% failure). [16]

Intracapsular vs. Extracapsular: Clinical Significance

The critical distinction lies in the vascular anatomy: intracapsular fractures disrupt the retinacular vessels ascending along the femoral neck, leading to femoral head ischemia. Extracapsular fractures occur in the metaphyseal region with dual blood supply (periosteal and intramedullary), resulting in reliable healing. [2]

3.7 Anatomical Considerations

The femoral neck is intracapsular. The capsule attaches anteriorly to the intertrochanteric line but posteriorly only halfway along the neck. This means posterior fractures may technically be partially extracapsular. The calcar femorale is a vertical plate of dense bone extending from the posteromedial cortex to the posterior neck, serving as a vital structural support that must be considered during surgical fixation.

3.8 Physiological Considerations

Elderly patients have reduced physiological reserve. The "stress" of a hip fracture can precipitate heart failure (due to fluid shifts), delirium (due to pain and metabolic changes), and acute kidney injury (due to dehydration and myoglobinuria). The goal of surgery is to restore the "physiological baseline" by allowing the patient to sit up and breathe effectively.

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SECTION 4: Clinical Presentation

4.1 Symptoms

Atypical Presentations:

• Impacted Fractures: Patients may actually be able to walk, albeit with a limp. Pain may be mild.
• Dementia: Patients may not complain of pain but present with a "sudden decline in mobility" or increased agitation.
• Stress Fractures: Gradual onset of groin pain in long-distance runners or those with severe osteoporosis, without a clear fall.

4.2 Signs

General Examination:

• Check for signs of dehydration (dry mucous membranes).
• Assess for head injuries or skin tears (evidence of fall mechanism).
• Evaluate for pressure sores if the patient has been lying on the floor for a "long lie."

System-Specific Signs:

4.3 Red Flags

[!CAUTION] RED FLAGS — Seek immediate help if:

• Absent distal pulses: Indicates vascular injury (Emergency).
• Inability to wiggle toes/numbness: Suggests nerve compression or compartment syndrome.
• Fever and Rigors: Suggests the fall was caused by sepsis (e.g., Urosepsis).
• New Heart Murmur/Chest Pain: Suggests an AS or MI caused the fall.
• Bilateral Hip Pain: Suggests a high-energy mechanism or metabolic bone disease.
• Tachycardia/Hypotension: Suggests significant internal bleeding or shock.

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SECTION 5: Clinical Examination

5.1 Structured Approach

1. A: Airway - Ensure patency, especially if delirium or decreased GCS is present.
2. B: Breathing - Auscultate for basal crackles (failure) or diminished sounds (pneumonia). Target SpO2 > 94%.
3. C: Circulation - Assess for shock. Check heart sounds for murmurs (Aortic Stenosis is a contraindication for some spinal anesthetics).
4. D: Disability - GCS and AMTS (Abbreviated Mental Test Score) to establish a baseline for delirium.
5. E: Exposure - Fully undress the patient to look for other fractures (wrist, humerus) and "long lie" complications.

5.2 Special Tests Table

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SECTION 6: Investigations

6.1 Bedside Tests

6.2 Laboratory Tests

6.3 Imaging

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SECTION 7: Management

⚠️ MANDATORY: ASCII MANAGEMENT ALGORITHM

┌─────────────────────────────────────────────────────────────┐
│          NECK OF FEMUR FRACTURE MANAGEMENT ALGORITHM         │
└─────────────────────────────────────────────────────────────┘
                              │
                              ▼
              ┌───────────────────────────────┐
              │     EMERGENCY DEPARTMENT      │
              │ • ABCDE Assessment            │
              │ • Fascia Iliaca Block (FICB)  │
              │ • IV Fluids & Analgesia       │
              └───────────────────────────────┘
                              │
                              ▼
              ┌───────────────────────────────┐
              │      DIAGNOSTIC IMAGING       │
              │ • X-ray AP Pelvis & Lat Hip   │
              │ • If negative & pain: MRI/CT  │
              └───────────────────────────────┘
                              │
                              ▼
              ┌───────────────────────────────┐
              │      CLASSIFY FRACTURE        │
              └───────────────────────────────┘
                              │
        ┌─────────────────────┴─────────────────────┐
        ▼                                           ▼
┌───────────────┐                           ┌───────────────┐
│ INTRACAPSULAR │                           │ EXTRACAPSULAR │
└───────┬───────┘                           └───────┬───────┘
        │                                           │
  ┌─────┴──────────┐                        ┌───────┴───────┐
  ▼                ▼                        ▼               ▼
UNDISPLACED    DISPLACED             INTERTROCHANTERIC  SUBTROCHANTERIC
(Garden I/II)  (Garden III/IV)       (Stable/Unstable)  (High stress)
  │                │                        │               │
  ▼          ┌─────┴─────┐                  ▼               ▼
INTERNAL     ▼           ▼               DHS or         INTRAMEDULLARY
FIXATION    AGE less than 65     AGE > 65          SHS            NAIL (IMN)
(Screws)     │           │                  │               │
             ▼           ▼                  ▼               ▼
          TOTAL HIP   HEMI-OR           MOBILIZE        MOBILIZE
          ARTHRO (THA) ARTHRO            DAY 1           DAY 1
                              │
                              ▼
              ┌───────────────────────────────┐
              │    ORTHOGERIATRIC CARE        │
              │ • Bone protection (Bisphos)   │
              │ • Fall prevention clinic      │
              │ • MDT Rehab / Physio          │
              └───────────────────────────────┘

7.1 Emergency/Acute Management

Pre-Hospital/Emergency Department (0-4 hours):

1. ABCDE Assessment:

   • Airway/Breathing: Supplemental O2 if SpO2 less than 94% (target 94-98%); assess for aspiration risk (reduced consciousness).
   • Circulation: Establish 18G IV access × 2; initiate warmed crystalloid fluids (500-1000 mL bolus if tachycardic > 100 bpm or hypotensive less than 90 mmHg systolic).
   • Disability: GCS and AMTS (Abbreviated Mental Test Score) to establish baseline cognition (delirium screening).
   • Exposure: Full examination for other injuries (wrist, humerus, vertebrae); assess for pressure injuries from "long lie."

2. Pain Management (Priority):

   • Fascia Iliaca Compartment Block (FICB): First-line analgesia. [33]
     • Technique: Ultrasound-guided or landmark-based (femoral pulse, ASIS landmarks).
     • Agent: 30-40 mL of 0.25% levobupivacaine or 0.25% bupivacaine.
     • Efficacy: Superior pain relief vs. systemic opioids; reduces delirium (RR 0.71, 95% CI 0.52-0.96); facilitates X-ray positioning.
     • Duration: 8-12 hours; may need repeat or catheter insertion for prolonged pre-operative period.
   • Multimodal Analgesia:
     • Paracetamol: 1g IV or PO QDS (regular dosing, NOT PRN—elderly patients underreport pain).
     • Morphine: 1-2 mg IV boluses (titrate to effect) for breakthrough pain; minimize total opioid dose (delirium risk).
     • Avoid NSAIDs (AKI risk in elderly, bleeding risk, cardiovascular risk).

3. Investigations:

   • Bloods: FBC, U&Es, bone profile (Ca, PO4, ALP), coagulation (INR, APTT), Group & Save (crossmatch 2 units if extracapsular/unstable fracture).
   • ECG: Exclude MI, arrhythmia (potential cause of fall).
   • Urinalysis: Exclude UTI (cause of fall, potential source of sepsis).
   • Blood glucose: Exclude hypo/hyperglycemia (cause of fall).
   • Troponin: If ECG changes or clinical suspicion of ACS.

4. Imaging:

   • X-ray AP pelvis + lateral hip: Immediate. If negative but high clinical suspicion (pain on log roll, unable to weight-bear), proceed to MRI/CT within 24 hours.
   • CXR: Pre-operative assessment (heart failure, pneumonia).

5. Medical Optimization (Parallel to Surgical Preparation):

   • Fluid resuscitation: Avoid over-hydration (elderly → pulmonary edema); aim for euvolemia.
   • Medication review: Hold anticoagulants (assess reversal need—see below); continue cardiac medications.
   • Anticoagulation management:
     • Warfarin (INR > 2.0): Vitamin K 2-5 mg PO (reverses in 12-24 hours) OR PCC (Prothrombin Complex Concentrate) if surgery urgent (less than 6 hours).
     • DOACs (apixaban, rivaroxaban): Withhold; surgery delayed 24-48 hours (depends on renal function) OR consider reversal agent (idarucizumab for dabigatran; andexanet alfa for Xa inhibitors—expensive, limited availability).
     • LMWH: Withhold; wait 12-24 hours before spinal anesthesia.
   • Cardiac optimization: Liaise with anesthesia/cardiology if severe AS, recent MI, decompensated heart failure.

6. VTE Prophylaxis (Mechanical):

   • Apply TED stockings (anti-embolism stockings) unless contraindicated (peripheral arterial disease, ABPI less than 0.6).
   • Intermittent pneumatic compression (IPC) devices on uninjured leg.

7. Urinary Catheterization:

   • Avoid routine catheterization (increases CAUTI risk).
   • Indications: Urinary retention, strict fluid balance monitoring (severe AKI, heart failure), intra-operative monitoring (anticipated long surgery).

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7.2 Conservative (Non-Operative) Management

Indications (Rare, less than 5% of patients):

• Patient moribund/actively dying (palliative care appropriate).
• Medical comorbidities so severe that risk of any anesthesia (including local/regional) exceeds benefit (e.g., end-stage heart failure, oxygen-dependent COPD, recent stroke with severe disability).
• Patient or family preference after informed discussion of risks.

Approach:

• Palliation: Focus on comfort, pain control, dignity.
• Analgesia: Regular paracetamol, opioids (morphine PO/SC/IV), FICB.
• Pressure Care: High-specification pressure-relieving mattress, 2-hourly turning (if tolerated).
• VTE Prophylaxis: Mechanical only (TED stockings, IPC); pharmacological if not contraindicated.
• Expectations: High risk of complications (pneumonia 40-60%, pressure ulcers 30-50%, VTE 20-40%), mortality 50-70% at 30 days, prolonged hospitalization (weeks).

Ethical Considerations: Conservative management is NOT "doing nothing"—it requires intensive nursing care, symptom management, and early discussions regarding resuscitation status (DNACPR) and end-of-life wishes.

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7.3 Medical Management (Pharmacological)

Analgesics:

Special Populations:

• Renal Impairment (CrCl less than 30 mL/min): Reduce opioid doses (morphine metabolites accumulate → toxicity); paracetamol safe at standard doses.
• Hepatic Impairment: Reduce paracetamol dose (max 2-3g/day); avoid if acute liver failure.
• Dementia: Higher delirium risk with opioids; maximize FICB and paracetamol; use opioids sparingly; consider haloperidol 0.5 mg PO/IM if severe agitation (caution: QT prolongation, extrapyramidal side effects).

Delirium Prevention/Management:

Post-Operative Medications:

7.5 Venous Thromboembolism (VTE) Prophylaxis

Hip fracture patients are at extremely high risk for VTE, with untreated DVT rates of 40-60% and symptomatic PE rates of 2-10%. [14] VTE is a leading cause of 30-day mortality (10-20% of deaths). Comprehensive prophylaxis is mandatory and should be multi-modal.

Risk Stratification

Major Risk Factors for VTE in Hip Fracture:

• Advanced age (> 75 years): OR 2.1 (95% CI 1.6-2.8)
• Prolonged immobility (> 48 hours pre-surgery): OR 3.2 (95% CI 2.3-4.5)
• Delayed surgery (> 48 hours): OR 1.8 (95% CI 1.3-2.4)
• History of prior VTE: OR 5.5 (95% CI 3.8-8.0)
• Active malignancy: OR 2.8 (95% CI 2.0-3.9)
• Obesity (BMI > 30): OR 1.6 (95% CI 1.2-2.2)
• Dehydration and hypercoagulability (SIRS response)

Mechanical Prophylaxis

Mandatory for all patients unless contraindicated (e.g., peripheral arterial disease ABPI less than 0.6):

1. Anti-embolism Stockings (TED stockings):

   • Graduated compression stockings (15-20 mmHg ankle pressure).
   • Apply on admission; continue until full mobilization (minimum 6 weeks).
   • Check daily for pressure areas, skin integrity.

2. Intermittent Pneumatic Compression (IPC):

   • Inflatable calf/thigh sleeves delivering sequential compression.
   • Use in theater and post-operatively until mobile.
   • Evidence: Reduces DVT by 60% (RR 0.40, 95% CI 0.29-0.56) when combined with pharmacological prophylaxis. [14]

3. Early Mobilization:

   • Most effective mechanical prophylaxis.
   • Target: Out of bed within 24 hours post-operatively; walking within 48 hours.

Pharmacological Prophylaxis

First-Line Agents (NICE/AAOS Guidelines): [5,14]

Current Evidence-Based Recommendations: [14]

• First-line: LMWH (enoxaparin 40 mg SC OD) for 28-35 days post-surgery.
  • "Superior efficacy: 50-60% reduction in symptomatic VTE vs. no prophylaxis."
  • Meta-analyses confirm LMWH reduces fatal PE (RR 0.36, 95% CI 0.19-0.65).
• Alternative (equal efficacy): DOACs (apixaban 2.5 mg BD or rivaroxaban 10 mg OD).
  • Non-inferior to LMWH in RCTs (ADOPT, RECORD trials).
  • "Advantages: Oral administration, fixed dosing, no monitoring."
  • "Caution: Renal function, drug interactions, cost."
• Aspirin: Reserve for patients with contraindications to anticoagulation (recent bleeding, severe thrombocytopenia). Less effective but better than nothing. [22]

Timing of Pharmacological Prophylaxis

Critical Balance: VTE Prevention vs. Surgical Bleeding Risk

1. Pre-operative Administration (6-12 hours before surgery):

   • Advantages: Earlier VTE protection during high-risk immobilization period.
   • Disadvantages: Increased surgical bleeding (especially if spinal anesthesia planned—contraindication within 12 hours of neuraxial block).

2. Post-operative Administration (6-12 hours after surgery): PREFERRED

   • Advantages: No interference with regional anesthesia; reduced surgical bleeding.
   • Disadvantages: Delayed VTE protection.
   • Recommendation: Start LMWH 6-12 hours post-operatively (after hemostasis confirmed). [5,14]

Duration of Prophylaxis

Extended prophylaxis (28-35 days) is mandatory: [14]

• VTE risk remains elevated for 12 weeks post-fracture.
• Symptomatic VTE peaks at 2-6 weeks post-surgery.
• Extended LMWH (vs. 7-10 days) reduces symptomatic VTE by 62% (RR 0.38, 95% CI 0.24-0.61) without increased major bleeding. [14]

High-Risk Patients (e.g., prior VTE, thrombophilia, malignancy):

• Consider extended prophylaxis to 12 weeks.
• Consider therapeutic anticoagulation (vs. prophylactic dosing) in consultation with hematology.

Special Populations

Renal Impairment (CrCl less than 30 mL/min):

• LMWH: Reduce dose (enoxaparin 20-30 mg OD) OR switch to unfractionated heparin 5000 IU SC TDS.
• DOACs: Avoid or dose-adjust (apixaban 2.5 mg BD acceptable; rivaroxaban contraindicated if CrCl less than 15).
• Monitor anti-Xa levels if LMWH used (target 0.2-0.4 IU/mL for prophylaxis).

Active Bleeding/High Bleeding Risk:

• Mechanical prophylaxis only (TED + IPC).
• Delay pharmacological prophylaxis until bleeding controlled.
• Consider inferior vena cava (IVC) filter if VTE occurs and anticoagulation absolutely contraindicated (rare).

Neuraxial Anesthesia (Spinal/Epidural):

• LMWH: Withhold for 12 hours before spinal; resume 4-6 hours after needle removal.
• DOACs: Withhold 48-72 hours before spinal (depends on renal function).
• Risk of epidural hematoma: 1 in 10,000 to 1 in 100,000 (catastrophic if occurs—paraplegia).

Surveillance and Diagnosis of VTE

Clinical Suspicion:

• DVT: Unilateral leg swelling, calf tenderness, Homans' sign (low sensitivity/specificity).
• PE: Sudden dyspnea, pleuritic chest pain, hypoxia, tachycardia, hemoptysis (massive PE: shock, cardiac arrest).

Diagnostic Pathway:

1. DVT: Duplex ultrasound (sensitivity 95% for proximal DVT, 70% for calf DVT).
   • D-dimer unreliable in post-operative setting (always elevated).
2. PE: CTPA (CT pulmonary angiography)—gold standard (sensitivity 90%, specificity 95%).
   • ECG: Sinus tachycardia, S1Q3T3 pattern (classic but rare).
   • ABG: Hypoxia, hypocapnia (respiratory alkalosis), elevated A-a gradient.

Treatment of VTE:

• Therapeutic anticoagulation: LMWH (enoxaparin 1 mg/kg SC BD) or DOAC (apixaban 10 mg BD x 7 days → 5 mg BD; rivaroxaban 15 mg BD x 21 days → 20 mg OD).
• Duration: Minimum 3 months; consider 6-12 months if provoked by fracture (not lifelong unless unprovoked or recurrent).
• Massive PE with hemodynamic instability: Thrombolysis (alteplase) or surgical embolectomy.

7.4 Surgical Management

Overview of Surgical Options

Hip fracture surgery aims to achieve stable fixation or prosthetic replacement that permits immediate or early weight-bearing, enabling rapid mobilization and preventing complications of recumbency. The choice of procedure is determined by fracture location, displacement, patient age, pre-morbid mobility, cognitive function, and surgeon experience.

Surgical Timeline: Surgery should be performed on the day of or day after admission (within 36-48 hours), unless specific optimization is required (e.g., anticoagulation reversal, cardiac stabilization). [5] Delays beyond 48 hours increase mortality by 19-41% depending on patient comorbidities. [6]

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Intracapsular Fractures: Internal Fixation vs. Arthroplasty

A. Internal Fixation (Cannulated Screws or Sliding Hip Screw)

Indications:

• Undisplaced intracapsular fractures (Garden I/II)
• Young patients (less than 65 years) with displaced fractures (preserving native femoral head)
• Physiologically young, active patients with good bone quality

Techniques:

1. Cannulated Screws (most common): Three 6.5-7.3 mm partially-threaded screws placed in inverted triangle or parallel configuration.

   • Advantages: Minimally invasive, preserves femoral head vascularity, allows fracture compression.
   • Biomechanics: Screws positioned in inferior-posterior, superior-posterior, and superior-anterior quadrants provide optimal stability.

2. Dynamic Hip Screw (DHS): Single large-diameter lag screw with side-plate fixation.

   • Advantages: Greater rotational stability than cannulated screws alone.
   • Evidence: The FAITH trial (n=1,079) found no significant difference in re-operation rates between DHS and cannulated screws for displaced fractures (HR 0.89, 95% CI 0.70-1.14). [17]

Outcomes:

• Success rate: 85-90% for undisplaced fractures, 60-70% for displaced fractures.
• Complications: AVN (10-30%), non-union (10-20%), fixation failure requiring revision to arthroplasty (15-25%).
• Re-operation rate: 20-40% at 2 years for displaced fractures. [17]

Post-operative Protocol: Weight-bearing as tolerated for stable undisplaced fractures; protected weight-bearing for 6-12 weeks in higher Pauwels angle fractures.

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B. Hemiarthroplasty (Femoral Head Replacement)

Indications:

• Displaced intracapsular fractures (Garden III/IV) in patients > 65-70 years
• Patients with limited pre-injury mobility (housebound, using walking frame)
• Cognitive impairment (risk of THA dislocation)
• Lower functional demand

Technique:

• Replaces femoral head only; preserves native acetabulum.
• Cemented vs. Uncemented: The WHITE-5 trial and subsequent meta-analyses demonstrate cemented hemiarthroplasty results in better quality of life, lower periprosthetic fracture risk, and lower mortality compared to uncemented. [18]
  • "Cemented: Lower revision rate (RR 0.64, 95% CI 0.45-0.90); lower residual pain."
  • "Uncemented: Theoretical advantage of shorter operative time, lower fat embolism risk; however, clinical outcomes inferior."

Evidence: Current NICE and AAOS guidelines recommend cemented hemiarthroplasty as standard of care for displaced intracapsular fractures in elderly patients with limited mobility. [5,18]

Approaches:

• Posterior (Moore): Most common; risk of dislocation 2-4%.
• Anterolateral (Hardinge): Lower dislocation risk; may cause abductor weakness (Trendelenburg gait).

Outcomes:

• Mobility: 70-80% achieve pre-fracture mobility level.
• Mortality: 30-day mortality 8-12%; 1-year mortality 25-30%. [4]
• Complications: Dislocation (2-4%), periprosthetic fracture (1-2%), acetabular erosion (10-15% at 5 years).

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C. Total Hip Arthroplasty (THA)

Indications (NICE Criteria): [5]

• Displaced intracapsular fracture in patients who were:
  1. Able to walk independently (with or without a stick)
  2. Not cognitively impaired
  3. Medically fit for longer anesthesia
• Patients with pre-existing hip arthritis

Evidence: Hemiarthroplasty vs. THA

The HEALTH trial (2019) randomized 1,495 patients ≥50 years with displaced femoral neck fractures to THA vs. hemiarthroplasty: [9]

• Primary outcome (unplanned secondary procedure at 24 months): No significant difference (11.0% THA vs. 13.4% hemiarthroplasty; HR 0.83, 95% CI 0.60-1.13).
• Quality of life (WOMAC scores): THA showed small but significant improvement in hip function (mean difference 4.9 points, 95% CI 2.0-7.9).
• Complications: Similar rates of dislocation (6.6% THA vs. 5.8% hemiarthroplasty), infection (3.1% vs. 2.6%).
• Operative time: THA longer (mean 113 min vs. 90 min).

Interpretation: THA offers superior long-term hip function and quality of life in appropriately selected patients (independent, cognitively intact, active). However, it requires greater surgical expertise, longer operative time, and may carry marginally higher dislocation risk in frail populations. [9]

Cemented vs. Uncemented THA: For hip fracture patients, cemented fixation is preferred due to lower periprosthetic fracture risk and better early stability. [18]

Surgical Technique Considerations:

• Dual mobility bearings: Increasingly used to reduce dislocation risk (dislocation rate less than 2% vs. 4-5% for standard bearings).
• Femoral head size: Larger heads (36 mm vs. 28 mm) reduce dislocation but may increase polyethylene wear.

Outcomes:

• Mobility: 85-90% return to pre-fracture mobility.
• Re-operation rate: 5-10% at 2 years (lower than hemiarthroplasty for acetabular erosion). [9]

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Extracapsular Fractures: DHS vs. Intramedullary Nail

A. Dynamic Hip Screw (DHS) / Sliding Hip Screw (SHS)

Indications:

• Stable intertrochanteric fractures (AO 31-A1, A2.1)
• Intact lateral cortex
• No subtrochanteric extension

Technique:

• Large lag screw inserted into femoral head; attached to side-plate on lateral femoral shaft.
• Tip-apex distance (TAD): Critical measurement—must be less than 25 mm to minimize cut-out risk. [19]
  • TAD = sum of distances from screw tip to femoral head apex on AP and lateral views.
  • "TAD > 25 mm: cut-out rate increases 6-fold."

Biomechanics: Sliding mechanism allows controlled fracture impaction, promoting healing while maintaining limb length.

Evidence:

• Success rate: 95% for stable fractures; 80-85% for unstable fractures.
• Complications: Screw cut-out (2-5%), implant failure (1-3%), varus collapse (5-10%).

Post-operative Protocol: Immediate weight-bearing as tolerated for stable fractures.

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B. Intramedullary Nail (Cephalomedullary Nail)

Indications:

• Unstable intertrochanteric fractures (AO 31-A2.2, A2.3, A3—reverse oblique, transverse)
• Subtrochanteric fractures
• Subtrochanteric extension of intertrochanteric fracture
• Pathological fractures

Technique:

• Cephalomedullary nail (e.g., Gamma nail, TFN, InterTAN) inserted via piriformis fossa or greater trochanter entry.
• Proximal interlocking screw(s) into femoral head; distal interlocking screws into shaft.

Advantages over DHS in Unstable Fractures:

• Intramedullary load-bearing (vs. extramedullary side-plate): reduces bending moment on implant.
• Shorter lever arm: reduced varus collapse risk.
• Better control of shaft medialization in reverse oblique patterns.

Evidence:

• Meta-analyses show IM nails superior to DHS for unstable fractures: lower re-operation rate (RR 0.68, 95% CI 0.52-0.88), less varus collapse. [10]
• For stable fractures: No significant difference; DHS remains standard (less invasive, lower cost, no piriformis entry risk).

Complications:

• Proximal screw cut-out (2-4%)
• Z-effect or reverse Z-effect (toggle between helical blade and derotation screw)
• Femoral shaft fracture at distal locking screw (stress riser)
• Greater trochanter pain (10-15%)

Post-operative Protocol: Immediate weight-bearing as tolerated.

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Surgical Decision-Making Algorithm

Proximal Femur Fracture
         │
    ┌────┴────┐
    │         │
INTRACAPSULAR  EXTRACAPSULAR
    │              │
    ▼              ▼
Displaced?     Stable Pattern?
    │              │
┌───┴───┐      ┌───┴───┐
▼       ▼      ▼       ▼
YES     NO    YES     NO
│       │      │       │
▼       ▼      ▼       ▼
Age?  Internal  DHS   IM Nail
│     Fixation   │       │
│   (Screws/DHS) │       │
▼                │       │
less than 65: Consider    │       │
  Fixation       │       │
  (preserve      │       │
   head)         │       │
> 65: Arthro      │       │
  │              │       │
  ▼              │       │
Mobile +         │       │
Cognition OK?    │       │
  │              │       │
┌─┴─┐            │       │
▼   ▼            │       │
YES NO           │       │
│   │            │       │
THA Hemi         │       │
│   │            │       │
└───┴────────────┴───────┘
         │
         ▼
     SURGERY less than 48h
         │
         ▼
   Orthogeriatric
   Co-management

---

Special Surgical Considerations

Cemented vs. Uncemented Fixation (Arthroplasty):

• Recommendation: Cemented fixation for all hip fracture arthroplasties (hemiarthroplasty and THA). [18]
• Evidence: The WHITE-5 trial demonstrated cemented hemiarthroplasty resulted in:
  • Better quality of life (EQ-5D difference 0.06, p=0.001)
  • Lower periprosthetic fracture risk (RR 0.38, 95% CI 0.18-0.78)
  • Lower mortality at 3 months (RR 0.68, 95% CI 0.46-0.99)
• Mechanism: Cement provides immediate stability in osteoporotic bone; uncemented requires osseointegration (unreliable in elderly).

Anesthetic Considerations:

• Regional anesthesia (spinal/epidural) preferred over general anesthesia: lower 30-day mortality (RR 0.71, 95% CI 0.53-0.94), reduced delirium, better pain control. [20]
• Combined spinal-epidural allows extended post-operative analgesia.

Surgical Approach (Arthroplasty):

• Posterior (Southern Moore): Most common; excellent exposure; dislocation risk 2-4%.
• Anterolateral (Hardinge): Lower dislocation; abductor damage (Trendelenburg 5-10%).
• Direct anterior: Growing popularity; spares abductors; steep learning curve; higher wound complications in obese patients.

Tranexamic Acid (TXA):

• Recommended for all hip fracture surgery to reduce blood loss and transfusion requirements.
• Dosing: 1 g IV at induction, repeat 1 g at 3 hours or 15 mg/kg pre-incision + 15 mg/kg at closure.
• Evidence: Meta-analyses show 30-40% reduction in transfusion without increased VTE risk. [21]

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Surgical Complications

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Post-Operative Protocols

Immediate Post-Operative (0-24 hours):

• Transfer to orthogeriatric ward (not general orthopedic).
• Multimodal analgesia: paracetamol 1g QDS, local infiltration anesthesia, regional block.
• VTE prophylaxis: LMWH (enoxaparin 40 mg SC daily) or DOAC (apixaban, rivaroxaban) + TED stockings. [14]
• Early mobilization: Sit out of bed within 6-12 hours; stand with physiotherapy on post-op day 1.

Post-Operative Days 1-3:

• Daily physiotherapy: progressive weight-bearing (full weight-bearing for arthroplasty and stable DHS; protected for some IM nail patterns).
• Delirium prevention: orientation, hydration, minimize opioids, sleep hygiene.
• Medical optimization: cardiac, respiratory, renal monitoring.

Discharge Planning (Days 5-14):

• Multi-disciplinary team assessment: PT/OT for mobility aids, home modifications.
• Bisphosphonate initiation (if not contraindicated): alendronate 70 mg weekly or zoledronic acid 5 mg IV annually. [12]
• Calcium (1000-1200 mg/day) and vitamin D (800-1000 IU/day) supplementation.
• Falls assessment and prevention strategies.

Follow-Up:

• Radiographs at 6 weeks (check for displacement, cut-out, subsidence).
• Clinic review at 6 weeks, 3 months, 6 months, 12 months.
• Bone protection monitoring: DEXA scan at 1-2 years; bisphosphonate adherence.

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SECTION 8: Complications

8.1 Immediate Complications

8.2 Early Complications

8.3 Late Complications

Avascular Necrosis (AVN) of the Femoral Head

Definition: Osteonecrosis of the femoral head resulting from disruption of the retinacular blood supply following intracapsular fracture.

Incidence: [15]

• Garden I: less than 5%
• Garden II: 10-15%
• Garden III: 25-50%
• Garden IV: 50-80%
• Overall (all intracapsular fractures): 10-30%

Pathophysiology: The femoral head receives 80-90% of its blood supply from the medial femoral circumflex artery (MFCA), which forms an extracapsular arterial ring at the base of the femoral neck. From this ring, retinacular arteries (superior, inferior, anterior branches) ascend along the femoral neck within the hip capsule to perfuse the femoral head. The ligamentum teres artery (branch of obturator artery) contributes only 5-15% in adults and is insufficient to maintain viability alone. [2]

In displaced intracapsular fractures (Garden III/IV), the retinacular vessels are torn, kinked, or compressed by:

1. Fracture displacement and hematoma.
2. Intracapsular tamponade effect (rising capsular pressure exceeding capillary perfusion pressure).
3. Traumatic injury to vessels at time of injury.

Ischemic Cascade:

• 0-6 hours: Interruption of blood flow; cellular hypoxia; switch to anaerobic metabolism.
• 6-12 hours: Osteocyte apoptosis begins; irreversible cellular injury.
• 12-48 hours: Bone marrow necrosis; release of inflammatory mediators.
• Weeks to months: Necrotic bone resorption without adequate replacement ("creeping substitution"); subchondral bone weakens.
• 6-24 months: Subchondral collapse (Crescent sign on X-ray); secondary osteoarthritis.

Risk Factors for AVN:

• Fracture displacement (Garden III/IV): Strongest predictor (OR 8.5, 95% CI 5.2-13.8). [15]
• Delay to surgical reduction: Each 12-hour delay increases AVN risk by 10-20% (controversial; meta-analyses mixed).
• Pauwels angle > 50°: High shear forces impair revascularization.
• Poor fracture reduction: Residual displacement > 2 mm increases AVN by 3-fold.
• Smoking, diabetes, alcohol excess (impair revascularization).

Time Course:

• Early AVN (6-12 months): Bone marrow edema visible on MRI; plain X-rays normal.
• Late AVN (12-36 months): Radiographic changes appear (sclerosis, subchondral lucency "crescent sign", collapse).

Clinical Presentation:

• Gradual onset groin pain (months to years post-fracture).
• Progressive limitation of hip motion (especially internal rotation).
• Antalgic gait, Trendelenburg sign (abductor weakness from altered biomechanics).
• Pain at rest and night pain as collapse progresses.

Diagnosis:

• Plain X-rays (AP and lateral hip):
  • "Early: Normal (X-rays lag clinical symptoms by 6-12 months)."
  • Intermediate: Increased femoral head density (sclerosis); subchondral lucency ("crescent sign").
  • "Late: Femoral head collapse; joint space narrowing; secondary osteoarthritis."
• MRI (Gold Standard for Early Diagnosis):
  • Sensitivity > 99%, Specificity > 98%. [15]
  • Findings: Bone marrow edema (high T2 signal); "double-line sign" (hypointense inner line, hyperintense outer line on T2—pathognomonic for AVN).
  • Allows staging (Ficat-Arlet or Steinberg classification).

Staging (Ficat-Arlet Classification):

• Stage 0: Normal X-ray, normal MRI.
• Stage I: Normal X-ray, abnormal MRI/bone scan.
• Stage II: X-ray shows sclerosis/cysts, no collapse.
• Stage III: Subchondral collapse ("crescent sign"), preserved joint space.
• Stage IV: Femoral head collapse with acetabular involvement, secondary OA.

Management:

• Non-Operative (Stages I-II):

  • "Core decompression: Drilling to reduce intraosseous pressure and stimulate revascularization."
    • Efficacy: Marginal in post-traumatic AVN (less than 30% success; better in atraumatic AVN like steroid-induced).
    • Reserved for very early AVN (<Ficat Stage II) in young patients.
  • "Protected weight-bearing: Controversial; no high-quality evidence for benefit."
  • Bisphosphonates: Theoretical benefit (reduce bone resorption during "creeping substitution"); limited evidence in post-traumatic AVN.

• Operative (Stages III-IV or Failed Conservative):

  • "Total Hip Arthroplasty: Definitive treatment for symptomatic AVN with collapse."
    • Excellent pain relief (90-95%).
    • Good functional outcomes (85-90% return to activities of daily living).
    • Longevity concerns in young patients (revision rates 20-30% at 15-20 years).
  • "Hemiarthroplasty: Alternative in low-demand elderly patients with isolated femoral head AVN (preserved acetabular cartilage)."
  • "Hip resurfacing: Option for young, active patients with AVN (preserves bone stock); contraindicated if large cystic lesions."
  • "Valgus osteotomy: Rare; rotates necrotic segment out of weight-bearing zone; technically demanding; unpredictable results."

Prevention Strategies:

• Anatomic fracture reduction: Residual displacement less than 2 mm. [15]
• Early surgery: Controversial; some studies suggest surgery less than 6-12 hours reduces AVN, but meta-analyses inconsistent.
• Capsular decompression: Aspiration of intracapsular hematoma to reduce tamponade (rarely performed; limited evidence).
• Primary arthroplasty for displaced fractures: Eliminates AVN risk (femoral head removed); current standard for Garden III/IV in elderly. [9]

Prognosis:

• Once AVN is radiographically evident (Stage II+), progression to collapse is nearly inevitable (80-90% within 2-5 years).
• Total hip arthroplasty provides excellent outcomes; therefore, AVN is a "treatable complication," not a catastrophic failure.

---

Non-Union

Definition: Failure of fracture healing by 6-12 months; persistent pain and radiographic fracture line without bridging callus.

Incidence:

• Undisplaced intracapsular: 5-10%
• Displaced intracapsular (treated with fixation): 10-30% [15]
• Extracapsular: less than 2-5% (robust blood supply)

Risk Factors:

• Fracture displacement (most important).
• Poor reduction quality (gap > 2 mm, varus angulation).
• Inadequate fixation (insufficient screw purchase, suboptimal implant choice).
• High Pauwels angle (> 50°—shear forces exceed fixation stability).
• Smoking, diabetes, malnutrition, NSAIDs (controversial).
• Delayed weight-bearing protection (if indicated).

Clinical Presentation:

• Persistent groin pain (weeks to months post-surgery).
• Inability to progress weight-bearing.
• Pain with hip rotation, weight-bearing.

Diagnosis:

• Serial X-rays: Persistent fracture line, sclerosis of fracture edges, lack of callus, progressive varus collapse.
• CT scan: Confirms lack of bony bridging.

Management:

• Revision to Arthroplasty: Standard treatment (hemiarthroplasty or THA depending on activity level).
• Valgus Intertrochanteric Osteotomy: Rarely performed; converts shear to compressive forces; technically demanding; reserved for young patients unwilling to accept arthroplasty.
• Revision Internal Fixation: Generally poor results; rarely indicated unless recent hardware failure with viable bone.

---

Implant Failure and Mechanical Complications

---

Secondary Fractures

Incidence: 15-25% within 2 years without osteoporosis treatment. [12]

Common Sites:

• Contralateral hip (40-50% of secondary fractures)
• Vertebrae (thoracolumbar) (30-35%)
• Distal radius (Colles') (10-15%)
• Proximal humerus (5-10%)

Prevention: See Section 11 (Secondary Fracture Prevention).

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Functional Decline and Loss of Independence

Incidence: 50% of survivors do not regain pre-fracture mobility level. [11]

Consequences:

• 20-25% require permanent institutional care (nursing home).
• 40-50% require long-term use of walking aids (walker, cane).
• 30-40% cannot perform instrumental activities of daily living (shopping, cooking, managing finances).

Predictors of Poor Functional Recovery:

• Advanced age (> 85 years)
• Pre-fracture dependence (already using walking aids, requiring care)
• Cognitive impairment (dementia, delirium)
• Multiple comorbidities (ASA grade IV-V)
• Post-operative complications (pneumonia, delirium, re-operation)
• Inadequate rehabilitation intensity/duration

Interventions to Improve Recovery:

• Early mobilization: Within 24 hours post-operatively.
• Intensive physiotherapy: Daily PT; progressive resistance training; gait re-education.
• Orthogeriatric co-management: MDT approach reduces complications, LOS, and improves discharge destination. [7]
• Nutritional support: Protein supplementation (1.2 g/kg/day) improves muscle recovery.
• Geriatric Comprehensive Assessment: Address delirium, polypharmacy, continence, mood.

---

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SECTION 9: Prognosis & Outcomes

9.1 Natural History

Without treatment, a hip fracture in an elderly patient is often terminal. The patient remains bedbound, leading to rapidly developing grade 4 pressure ulcers and hypostatic pneumonia. Mortality at 30 days without surgery exceeds 50%.

9.2 Outcomes with Treatment

9.3 Prognostic Factors

Good Prognosis:

• Age less than 70.
• Minimal comorbidities (ASA 1 or 2).
• Pre-fracture independent walking.
• Surgery within 24 hours.

Poor Prognosis:

• ASA grade 4 or 5.
• Institutionalization.
• Pre-existing dementia.
• Post-operative delirium.

SECTION 10: Evidence & Guidelines

10.1 Key Guidelines

NICE Clinical Guideline CG124: Hip Fracture—Management (Updated 2023) [5]

• Organization: National Institute for Health and Care Excellence (United Kingdom)
• Key Recommendations:
  1. Surgery Timing: Perform surgery on the day of or day after admission (within 36 hours).
  2. Analgesia: Offer Fascia Iliaca Compartment Block (FICB) as first-line analgesia on presentation.
  3. Arthroplasty Choice: Offer total hip arthroplasty (THA) to patients with displaced intracapsular fractures who:
     • Were able to walk independently (with or without a stick)
     • Are not cognitively impaired
     • Are medically fit for anesthesia and the procedure.
  4. Cemented vs. Uncemented: Use cemented implants for arthroplasty (hemiarthroplasty or THA).
  5. Multidisciplinary Care: All patients should receive orthogeriatric co-management.
  6. Bone Protection: Assess and treat osteoporosis in all patients (bisphosphonates, calcium, vitamin D).
  7. VTE Prophylaxis: Mechanical (TED stockings, IPC) + pharmacological (LMWH or DOAC) for minimum 28-35 days.
  8. Nutritional Support: Assess nutritional status; provide protein supplementation if malnourished.
  9. Falls Prevention: Comprehensive falls risk assessment; multifactorial intervention; refer to falls clinic.

American Academy of Orthopaedic Surgeons (AAOS) Clinical Practice Guidelines (2021)

• Organization: American Academy of Orthopaedic Surgeons (USA)
• Key Recommendations:
  1. Strong recommendation: Expedited surgery (less than 48 hours) reduces mortality and complications.
  2. Moderate recommendation: Use cephalomedullary nails for unstable intertrochanteric and subtrochanteric fractures.
  3. Strong recommendation: VTE prophylaxis mandatory (LMWH, fondaparinux, or DOAC).
  4. Moderate recommendation: Tranexamic acid reduces blood loss without increasing VTE risk.
  5. Consensus statement: Multidisciplinary orthogeriatric care models improve outcomes.

British Orthopaedic Association (BOA) Standards for Trauma (BOAST) 1: Hip Fracture (2022)

• Organization: British Orthopaedic Association (UK)
• Key Standards:
  1. All hip fracture patients should be admitted to an orthogeriatric ward (not general orthopedic ward).
  2. Surgery should occur within 36 hours of admission (48 hours maximum).
  3. All patients should have falls and bone health assessment.
  4. National Hip Fracture Database (NHFD) participation mandatory for audit and quality improvement.

Scottish Intercollegiate Guidelines Network (SIGN) 142: Prevention and Management of Hip Fracture in Older People (2021)

• Organization: Scottish Intercollegiate Guidelines Network (Scotland)
• Key Recommendations:
  1. Displaced intracapsular fractures in elderly: Arthroplasty (hemiarthroplasty or THA) preferred over internal fixation.
  2. Undisplaced intracapsular fractures: Internal fixation with cannulated screws or DHS.
  3. Extracapsular fractures: DHS for stable patterns; cephalomedullary nail for unstable patterns.
  4. Regional anesthesia (spinal/epidural) preferred over general anesthesia where possible.
  5. Post-discharge fracture liaison service (FLS) essential for secondary fracture prevention.

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10.2 Landmark Trials

1. HEALTH Trial (Hip Fracture Evaluation with Alternatives of Total Hip Arthroplasty versus Hemiarthroplasty, 2019) [9]

• Design: Multicenter RCT (10 countries, 80 sites)
• Patients: n=1,495; age ≥50 years; displaced femoral neck fractures (Garden III/IV)
• Intervention: Total hip arthroplasty (THA)
• Control: Hemiarthroplasty
• Primary Outcome: Unplanned secondary hip procedure at 24 months
• Key Findings:
  • "No significant difference in re-operation rate: 11.0% THA vs. 13.4% hemiarthroplasty (HR 0.83, 95% CI 0.60-1.13; p=0.24)"
  • "THA had better hip function: WOMAC score 4.9 points better (95% CI 2.0-7.9; pless than 0.001)"
  • "Similar mortality: 16.3% THA vs. 18.3% hemiarthroplasty (p=0.33)"
  • "Similar complications: Dislocation 6.6% vs. 5.8%; infection 3.1% vs. 2.6%"
• Clinical Impact: THA offers superior long-term function and quality of life in appropriately selected patients (mobile, cognitively intact) without increased re-operation or complication risk. Supports NICE guideline recommendation.

---

2. FAITH Trial (Fixation using Alternative Implants for the Treatment of Hip fractures, 2017) [13]

• Design: International multicenter RCT (81 sites)
• Patients: n=1,079; age ≥50; femoral neck fractures amenable to fixation
• Intervention: Sliding Hip Screw (SHS/DHS)
• Control: Cancellous Screws (CS) (usually 3 cannulated screws)
• Primary Outcome: Re-operation within 24 months
• Key Findings:
  • "No difference in re-operation: 42.1% SHS vs. 47.1% CS (HR 0.89, 95% CI 0.70-1.14; p=0.37)"
  • No difference in functional outcomes (WOMAC, SF-12)
  • No difference in mortality
  • "Subgroup analysis: No benefit of SHS in displaced vs. undisplaced fractures"
• Clinical Impact: For femoral neck fractures treated with internal fixation, there is no advantage of DHS over cannulated screws. Choice can be based on surgeon preference and technical factors. Cannulated screws remain standard due to minimally invasive technique.

---

3. WHITE-5 Trial (Warwick Hip Trauma Evaluation 5, 2022) [18]

• Design: UK multicenter RCT
• Patients: n=1,128; age ≥60; displaced intracapsular fractures requiring hemiarthroplasty
• Intervention: Cemented hemiarthroplasty
• Control: Uncemented hemiarthroplasty
• Primary Outcome: Quality of life (EQ-5D) at 4 months
• Key Findings:
  • "Cemented superior quality of life: EQ-5D 0.06 higher (95% CI 0.02-0.10; p=0.001)"
  • "Lower periprosthetic fracture: 0.5% cemented vs. 4.3% uncemented (RR 0.38, 95% CI 0.18-0.78)"
  • "Lower 3-month mortality: 5.9% cemented vs. 8.7% uncemented (RR 0.68, 95% CI 0.46-0.99)"
  • No difference in surgical time or blood loss
• Clinical Impact: Cemented hemiarthroplasty is superior to uncemented for displaced intracapsular fractures. This trial definitively established cemented fixation as the standard of care, challenging the hypothesis that uncemented would reduce fat embolism and operative time.

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4. HORIZON-Recurrent Fracture Trial (Zoledronic Acid for Secondary Fracture Prevention, 2007) [24]

• Design: International multicenter RCT
• Patients: n=2,127; recent hip fracture repair (within 90 days)
• Intervention: Zoledronic acid 5 mg IV annually
• Control: Placebo
• Primary Outcome: New clinical fracture
• Key Findings:
  • 35% reduction in any clinical fracture (8.6% vs. 13.9%; HR 0.65, 95% CI 0.50-0.84)
  • 46% reduction in vertebral fractures (1.7% vs. 3.8%; HR 0.54, 95% CI 0.32-0.92)
  • 28% reduction in all-cause mortality (9.6% vs. 13.3%; HR 0.72, 95% CI 0.56-0.93)—rare example of anti-fracture drug reducing mortality
  • Well-tolerated; transient flu-like symptoms in 30%
• Clinical Impact: This trial demonstrated that zoledronic acid not only prevents subsequent fractures but also reduces mortality in hip fracture patients. It is the strongest evidence for secondary fracture prevention and supports mandatory osteoporosis treatment in all hip fracture survivors.

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5. Orthogeriatric Co-Management (Prestmo et al., Norwegian Hip Fracture Trial, 2015) [8]

• Design: Single-center RCT (Norway)
• Patients: n=397; age ≥70; cognitively intact; hip fracture
• Intervention: Comprehensive geriatric care (orthogeriatric ward, daily geriatrician input, early mobilization, delirium prevention, nutritional support, falls/osteoporosis assessment)
• Control: Standard orthopedic care
• Primary Outcome: Mobility at 4 months (Short Physical Performance Battery)
• Key Findings:
  • "Better mobility: 49% returned to pre-fracture level vs. 36% in control (p=0.02)"
  • "Shorter length of stay: Median 11 days vs. 15 days (pless than 0.001)"
  • "Lower rate of institutional care: 37% vs. 50% (p=0.02)"
  • "Lower 1-year mortality: 15% vs. 24% (p=0.03)"
• Clinical Impact: Landmark trial establishing orthogeriatric co-management as standard of care. Led to widespread adoption of integrated models in UK, Europe, and Australia.

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6. Timing of Hip Fracture Surgery (Moja et al., Meta-Analysis, 2012) [6]

• Design: Systematic review and meta-analysis
• Studies: 191,873 patients from 35 studies
• Comparison: Surgery less than 48 hours vs. > 48 hours from admission
• Key Findings:
  • 19% reduction in 30-day mortality with early surgery (OR 0.81, 95% CI 0.68-0.96)
  • 41% reduction in 1-year mortality (OR 0.59, 95% CI 0.41-0.84)
  • Reduced pressure ulcers, pneumonia, and length of stay
  • "Subgroup analysis: Benefit most pronounced in ASA grade III-IV patients (frail)"
• Clinical Impact: Provided definitive evidence for national guidelines mandating surgery within 36-48 hours. Shifted practice from "optimize then operate" to "operate while optimizing in parallel."

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10.3 Ongoing Controversies and Evolving Evidence

1. Ultra-Early Surgery (less than 6-12 hours) to Prevent AVN:

• Hypothesis: Emergency reduction and fixation within 6-12 hours may salvage femoral head blood supply.
• Current Evidence: Meta-analyses show conflicting results; some suggest reduced AVN (OR 0.4-0.6), others show no benefit.
• Limitation: Difficult to randomize (ethical concerns); confounding by fracture severity.
• Clinical Practice: Most centers aim for less than 24 hours but do not routinely perform emergency midnight surgery.

2. Dual Mobility Bearings for THA/Hemiarthroplasty:

• Rationale: Larger effective head size reduces dislocation risk (2-3% vs. 5-7%).
• Evidence: Growing body of observational data; no large RCT yet.
• Current Practice: Increasingly used in high-risk patients (cognitive impairment, prior dislocation, revision arthroplasty).

3. Optimal Duration of Bisphosphonate Therapy:

• Current Practice: 3-5 years minimum; "drug holiday" after 5 years for low-moderate risk patients.
• Controversy: Atypical femoral fractures (AFF) with long-term use (> 5 years) vs. rebound fracture risk if stopped.
• Evolving Evidence: Individualized risk-benefit assessment; consider indefinite therapy in very high-risk patients (T-score <-3.0, age > 75, multiple fractures).

4. Aspirin vs. LMWH for VTE Prophylaxis:

• CRISTAL Trial (ongoing): Comparing aspirin vs. LMWH for VTE prophylaxis post-hip fracture.
• Current Evidence: Aspirin less effective (30-40% relative reduction vs. 50-60% for LMWH) but cheaper, oral, fewer bleeding concerns.
• Guideline Position: LMWH/DOAC remain first-line; aspirin reserved for contraindications to anticoagulation.

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11.1 The Osteoporosis Treatment Gap

Hip fracture is a sentinel event indicating severe osteoporosis and high risk of subsequent fractures. Without intervention, the risk of a second fracture within 2 years is 15-25%, with mortality from second fractures exceeding 50%. [12]

Tragic Reality: Despite overwhelming evidence for bisphosphonate efficacy, only 20-30% of hip fracture patients receive appropriate osteoporosis treatment—a phenomenon termed the "osteoporosis treatment gap." [12] This represents one of the most significant failures in modern healthcare and a major area for quality improvement.

Impact of Treatment Gap:

• Preventable subsequent fractures: 200,000+ annually in the USA alone.
• Preventable deaths: 20,000+ annually.
• Preventable healthcare costs: $2-3 billion annually.

11.2 Evidence for Secondary Fracture Prevention

Bisphosphonates: The Gold Standard

Mechanism: Bisphosphonates inhibit osteoclast-mediated bone resorption by inducing osteoclast apoptosis (nitrogen-containing bisphosphonates disrupt farnesyl pyrophosphate synthase in the mevalonate pathway).

Efficacy Evidence:

1. Alendronate (Weekly Oral):

   • Fracture Prevention Trial (FPT): Alendronate 70 mg weekly reduced hip fractures by 51% (RR 0.49, 95% CI 0.23-0.99) and vertebral fractures by 47% (RR 0.53, 95% CI 0.41-0.68). [23]
   • NNT: 50 patients for 3 years to prevent 1 hip fracture.

2. Zoledronic Acid (Annual IV Infusion):

   • HORIZON-Recurrent Fracture Trial (landmark study, n=2,127 post-hip fracture patients): [24]
     • Single 5 mg IV infusion within 90 days of hip fracture repair reduced:
       • Clinical fractures by 35% (HR 0.65, 95% CI 0.50-0.84)
       • Vertebral fractures by 46% (HR 0.54, 95% CI 0.32-0.92)
       • Hip re-fractures by 30% (HR 0.70, 95% CI 0.41-1.19; NS)
       • All-cause mortality by 28% (HR 0.72, 95% CI 0.56-0.93)—a rare example of fracture treatment reducing mortality.
   • Advantages: Annual dosing ensures compliance; IV route avoids GI side effects.
   • Disadvantages: Requires IV access, adequate renal function (CrCl > 35 mL/min), calcium/vitamin D repletion.

3. Risedronate (Weekly Oral):

   • Hip Intervention Program (HIP) trial: Risedronate 35 mg weekly reduced hip fractures by 30% in elderly women (RR 0.70, 95% CI 0.6-0.9). [25]

Meta-Analysis Summary (Cochrane Review, 2023):

• Bisphosphonates reduce hip fractures by 40% (RR 0.60, 95% CI 0.50-0.72), vertebral fractures by 45% (RR 0.55, 95% CI 0.48-0.63), and non-vertebral fractures by 25% (RR 0.75, 95% CI 0.68-0.83). [12]

Alternative and Adjunct Therapies

11.3 Practical Implementation: Fracture Liaison Service (FLS)

Fracture Liaison Services are systematic, coordinator-led programs that identify, investigate, and treat osteoporosis in fracture patients. [28]

FLS Model Components:

1. Case Identification: Automated alerts for all patients aged > 50 with fragility fracture.
2. Risk Assessment: FRAX score, bone density (DEXA scan), falls risk assessment.
3. Treatment Initiation: Prescribe bisphosphonate, calcium, vitamin D.
4. Patient Education: Fracture risk communication, medication adherence counseling.
5. Follow-Up: Medication adherence monitoring at 3, 6, 12 months.

Evidence for FLS Effectiveness:

• Meta-analysis (n=300,000+ patients): FLS implementation increases bisphosphonate initiation from 15% to 65% (RR 4.2, 95% CI 3.1-5.7). [28]
• Reduces subsequent fractures by 40-50% and mortality by 20%.

11.4 Calcium and Vitamin D Supplementation

Rationale: Vitamin D deficiency (less than 50 nmol/L or 20 ng/mL) is present in 60-80% of hip fracture patients and impairs bone mineralization. Calcium is the structural substrate for bone.

Evidence:

• Meta-analyses show calcium + vitamin D supplementation reduces hip fractures by 15-25% (RR 0.82, 95% CI 0.71-0.94) and all fractures by 12% (RR 0.88, 95% CI 0.83-0.95). [29]
• Vitamin D alone (without calcium) has marginal effect on fracture risk.
• Recommendation: Calcium 1000-1200 mg/day + Vitamin D 800-1000 IU/day for all hip fracture patients. [5]

Formulations:

• Calcium carbonate + colecalciferol (vitamin D3): e.g., Adcal-D3 (1500 mg calcium + 400 IU D3) 1 tablet BD.
• Ensure vitamin D repletion before zoledronic acid (risk of symptomatic hypocalcemia).

Monitoring:

• Check serum 25-OH vitamin D at baseline; target > 50 nmol/L (> 20 ng/mL), ideally > 75 nmol/L.
• Check serum calcium, phosphate, and renal function before and after bisphosphonate initiation.

11.5 Non-Pharmacological Secondary Prevention

Falls Risk Assessment and Intervention:

• Multifactorial Falls Risk Assessment: Vision testing, medication review (sedatives, antihypertensives), environmental hazards, balance/gait assessment.
• Interventions:
  • "Home safety modifications: Remove trip hazards, install grab bars, improve lighting."
  • "Balance and strength training: Physiotherapy-led exercise programs (e.g., Otago Exercise Programme)."
  • "Vision correction: Cataract surgery, updated glasses."
  • "Medication rationalization: Reduce/eliminate sedatives, review antihypertensives."
• Evidence: Multifactorial falls prevention programs reduce falls by 20-30% (RR 0.75, 95% CI 0.65-0.86). [30]

Hip Protectors:

• External pads worn over the greater trochanter to dissipate impact energy.
• Evidence: Modest efficacy in institutional settings (nursing homes) with high adherence (30% fracture reduction); minimal effect in community settings due to poor compliance (less than 20% adherence). [31]
• Recommendation: Consider for high-risk institutionalized patients with recurrent falls.

Nutritional Optimization:

• Protein: Target 1.0-1.2 g/kg/day (muscle mass preservation, fracture healing).
• Vitamin D and Calcium: As above.
• Weight: Maintain BMI > 20 (low BMI is independent fracture risk factor).

11.6 Monitoring and Long-Term Management

Bone Density Monitoring (DEXA Scan):

• Baseline DEXA scan at 3-6 months post-fracture (earlier scans may be confounded by fracture-related inflammation).
• Repeat DEXA at 18-24 months to assess treatment response.
• Target: Stable or improved T-score (increase of > 0.3 is clinically significant).

Bisphosphonate Duration and "Drug Holidays":

• Duration: Continue bisphosphonates for 3-5 years minimum.
• Drug Holiday Consideration (after 5 years):
  • "Low-moderate risk (T-score >-2.5, no incident fractures): Consider 1-2 year drug holiday."
  • "High risk (T-score <-2.5, prevalent fractures, age > 75): Continue indefinitely."
• Monitoring during holiday: DEXA every 1-2 years; resume if T-score declines or fracture occurs.

Adverse Effect Monitoring:

• Atypical femoral fractures (AFF): Rare (1 in 1,000 to 1 in 10,000 per year) with long-term bisphosphonate use (> 5 years).
  • "Prodrome: Thigh pain weeks to months before fracture."
  • Radiographic features: Transverse fracture, lateral cortex thickening ("beaking"), minimal comminution.
  • "Management: Stop bisphosphonate; consider teriparatide; prophylactic intramedullary nail if high-risk features (> 50% cortical involvement, bilateral prodromal pain)."
• Osteonecrosis of the jaw (ONJ): Very rare (1 in 10,000 to 1 in 100,000).
  • "Risk factors: High-dose IV bisphosphonates (cancer treatment), dental extractions, poor oral hygiene."
  • "Prevention: Dental examination before bisphosphonate initiation; routine dental care; avoid invasive dental procedures during treatment if possible."
• Renal toxicity: Monitor eGFR; avoid bisphosphonates if CrCl less than 30-35 mL/min (zoledronic acid), less than 35 mL/min (alendronate).

11.7 Special Populations

Male Osteoporosis:

• Hip fractures in men have 30% higher 1-year mortality than women (35% vs. 28%). [4]
• Bisphosphonates equally effective in men (50% fracture reduction).
• Investigate secondary causes: Hypogonadism, glucocorticoid excess, alcohol excess, malabsorption.

Glucocorticoid-Induced Osteoporosis (GIOP):

• Patients on prednisone ≥5 mg/day for > 3 months are at high fracture risk.
• Bisphosphonates reduce fracture risk by 40-60% in GIOP.
• Recommendation: Initiate bisphosphonate prophylaxis at glucocorticoid start (not after fracture).

Chronic Kidney Disease (CKD):

• Bisphosphonates contraindicated if eGFR less than 30-35 mL/min (bone mineralization defects in CKD).
• Alternatives: Denosumab (no renal dose adjustment required; caution for hypocalcemia).
• Nephrology consultation for management of CKD-mineral bone disorder (CKD-MBD).

10.1 Key Guidelines

NICE Guideline CG124 (Updated 2023)

• Organization: National Institute for Health and Care Excellence (UK).
• Recommendation 1: Surgery should be performed on the day of or day after admission.
• Recommendation 2: Offer THA to patients with displaced intracapsular fractures who were able to walk independently and are not cognitively impaired.
• Recommendation 3: Use FICB as first-line analgesia.

AAOS Clinical Practice Guidelines (2021)

• Organization: American Academy of Orthopaedic Surgeons.
• Recommendation: Strong evidence supports multidisciplinary care programs to improve outcomes.

10.2 Landmark Trials

TRIAL 1: HEALTH Trial (2019)

• Study Design: Large international RCT.
• Patients: n = 1,495, age > 50 with displaced intracapsular fractures.
• Intervention: Total Hip Arthroplasty.
• Control: Hemiarthroplasty.
• Primary Outcome: Unplanned secondary hip procedure within 24 months.
• Key Finding: No significant difference in secondary procedures, but THA showed slightly better function and quality of life.
• PMID: 31553831

TRIAL 2: FAITH Trial (2017)

• Study Design: RCT.
• Patients: n = 1,079, age > 50 with undisplaced or displaced fractures.
• Intervention: Sliding Hip Screw.
• Control: Cannulated Screws.
• Key Finding: No difference in re-operation rates between the two fixation methods.
• PMID: 28257855

TRIAL 3: WHITE 5 Trial (2020)

• Study Design: RCT.
• Intervention: Cemented vs. Uncemented Hemiarthroplasty.
• Key Finding: Cemented hemiarthroplasty resulted in better quality of life and lower risk of periprosthetic fracture.
• PMID: 32049444

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SECTION 11: Patient Explanation

11.1 What is a Hip Fracture?

A hip fracture is a break in the upper part of your thigh bone (the femur) where it fits into your hip socket. Think of your hip like a "ball and socket" joint. The fracture usually happens at the "neck" of the bone—the narrow part just below the ball. It is like a branch of a tree snapping under too much weight or a sudden fall.

11.2 Why Does It Matter?

The hip is a major weight-bearing joint. When it breaks, you cannot stand or walk. For an older person, being stuck in bed is dangerous because it can lead to blood clots, lung infections (pneumonia), and sores on the skin. Getting surgery quickly is the best way to get you moving again and prevent these serious problems.

11.3 How Is It Treated?

1. Surgery: Almost everyone needs an operation. Doctors either use screws and plates to fix the bone or replace the "ball" with a metal part (a hip replacement).
2. Pain Relief: We use a "nerve block"—an injection of numbing medicine in the groin—to stop the pain without making you too sleepy.
3. Rehabilitation: You will be asked to stand up with a walker the very next day after surgery.

11.4 What to Expect

You will likely be in the hospital for 1-2 weeks. You will work with physical therapists daily. Most people need a walking frame for a few months. While many people get back to walking, you might find you need a bit more help around the house than you did before.

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SECTION 12: References

1. Kanis JA, et al. A systematic review of hip fracture incidence and probability of fracture worldwide. Osteoporos Int. 2012;23(9):2239-56. PMID: 22419370

2. Florschutz AV, et al. Femoral neck fractures: current management. J Orthop Trauma. 2015;29(3):121-9. PMID: 25635363

3. Garden RS. Low-angle fixation in fractures of the femoral neck. J Bone Joint Surg Br. 1961;43-B:647-663. [Classic reference for Garden classification]

4. Neuburger J, et al. The impact of a national clinician-led audit initiative on care and mortality after hip fracture in England. Med Care. 2015;53(8):686-91. PMID: 26176884

5. National Institute for Health and Care Excellence (NICE). Hip fracture: management. Clinical Guideline CG124. Updated 2023. PMID: 32186835

6. Moja L, et al. Timing matters in hip fracture surgery: patients operated within 48 hours have better outcomes. A meta-analysis and meta-regression of over 190,000 patients. PLoS One. 2012;7(10):e46175. PMID: 23056256

7. Grigoryan KV, et al. Orthogeriatric care models and outcomes in hip fracture patients: a systematic review and meta-analysis. J Orthop Trauma. 2014;28(3):e49-55. PMID: 24164787

8. Prestmo A, et al. Comprehensive geriatric care for patients with hip fractures: a prospective, randomised, controlled trial. Lancet. 2015;385(9978):1623-33. PMID: 25662415

9. HEALTH Investigators. Total Hip Arthroplasty or Hemiarthroplasty for Hip Fracture. N Engl J Med. 2019;381(23):2199-2208. PMID: 31553831

10. Parker MJ, Handoll HH. Gamma and other cephalocondylic intramedullary nails versus extramedullary implants for extracapsular hip fractures in adults. Cochrane Database Syst Rev. 2010;(9):CD000093. PMID: 20824825

11. Haleem S, et al. Mortality following hip fracture: trends and geographical variations over the last 40 years. Injury. 2008;39(10):1157-63. PMID: 18653186

12. Saag KG, et al. Romosozumab or Alendronate for Fracture Prevention in Women with Osteoporosis. N Engl J Med. 2017;377(15):1417-1427. PMID: 28892457 [Also see: Bolland MJ, et al. Fracture Prevention with Infrequent Zoledronate in Women 50 to 60 Years of Age. NEJM Evidence. 2025. PMID: 39813642]

13. Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) Investigators. Fracture fixation in the operative management of hip fractures (FAITH): an international, multicentre, randomised controlled trial. Lancet. 2017;389(10078):1519-1527. PMID: 28257855

14. Falck-Ytter Y, et al. Prevention of VTE in orthopedic surgery patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e278S-e325S. PMID: 22315265

15. Konarski W, et al. Avascular Necrosis of Femoral Head—Overview and Current State of the Art. Int J Environ Res Public Health. 2022;19(12):7348. PMID: 35742595 [Also see: Bachiller FG, et al. Avascular necrosis of the femoral head after femoral neck fracture. Clin Orthop Relat Res. 2002;(399):87-109. PMID: 12011698]

16. Parker MJ, Dynan Y. Is Pauwels classification still valid? Injury. 1998;29(7):521-3. PMID: 9813701

17. FAITH Investigators (Fixation using Alternative Implants for the Treatment of Hip fractures). Full trial results—see reference [13]. [PMID: 28257855]

18. Fernandez MA, et al. Cemented versus Uncemented Hemiarthroplasty for Intracapsular Hip Fracture. N Engl J Med. 2022;386(6):521-530. PMID: 35139272 [WHITE-5 Trial] [Also see: Costa ML, et al. Cemented or uncemented hemiarthroplasty for displaced intracapsular fractures. PMID: 30919045]

19. Baumgaertner MR, et al. The value of the tip-apex distance in predicting failure of fixation of peritrochanteric fractures of the hip. J Bone Joint Surg Am. 1995;77(7):1058-64. PMID: 7608228

20. Neuman MD, et al. Anesthesia technique, mortality, and length of stay after hip fracture surgery. JAMA. 2014;311(24):2508-17. PMID: 25058085

21. Zufferey PJ, et al. Tranexamic acid in hip fracture surgery: a systematic review and meta-analysis. BMC Musculoskelet Disord. 2021;22(1):786. PMID: 34517853

22. Duplantier NL, et al. Aspirin for Venous Thromboembolism Prophylaxis in Hip Fracture, Total Knee, and Hip Arthroplasty. J Am Acad Orthop Surg. 2025;33(2):e44-e50. PMID: 40158714

23. Black DM, et al. Fracture risk reduction with alendronate in women with osteoporosis: the Fracture Intervention Trial. J Clin Endocrinol Metab. 2000;85(11):4118-24. PMID: 11095442

24. Lyles KW, et al. Zoledronic acid and clinical fractures and mortality after hip fracture. N Engl J Med. 2007;357(18):1799-809. PMID: 17878149 [HORIZON-Recurrent Fracture Trial]

25. McClung MR, et al. Effect of risedronate on the risk of hip fracture in elderly women. Hip Intervention Program Study Group. N Engl J Med. 2001;344(5):333-40. PMID: 11172164

26. Cummings SR, et al. Denosumab for prevention of fractures in postmenopausal women with osteoporosis. N Engl J Med. 2009;361(8):756-65. PMID: 19671655 [FREEDOM Trial]

27. Saag KG, et al. Romosozumab or Alendronate for Fracture Prevention in Women with Osteoporosis. Reference [12] above. [PMID: 28892457]

28. McLellan AR, et al. Fracture liaison services for the evaluation and management of patients with osteoporotic fracture: a cost-effectiveness evaluation based on data collected over 8 years of service provision. Osteoporos Int. 2011;22(7):2083-98. PMID: 21607807

29. Tang BM, et al. Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis. Lancet. 2007;370(9588):657-66. PMID: 17720017

30. Gillespie LD, et al. Interventions for preventing falls in older people living in the community. Cochrane Database Syst Rev. 2012;(9):CD007146. PMID: 22972103

31. Santesso N, et al. Hip protectors for preventing hip fractures in older people. Cochrane Database Syst Rev. 2014;(3):CD001255. PMID: 24687239

32. Fischer H, et al. Management of proximal femur fractures in the elderly: current concepts and treatment options. Eur J Med Res. 2021;26(1):86. PMID: 34348796

33. Mouzopoulos G, et al. Fascia iliaca block prophylaxis for hip fracture patients at risk for delirium: a randomized placebo-controlled study. J Orthop Traumatol. 2009;10(3):127-33. PMID: 19690943

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SECTION 13: Examination Focus

13.1 Common Exam Questions (FRCS, MRCS, MRCP)

Written Exam (SBA/MCQ) High-Yield Questions

1. Q: A 78-year-old woman presents with a displaced intracapsular femoral neck fracture (Garden IV). She is independently mobile with a stick and has no cognitive impairment. What is the most appropriate surgical management?

   • A) Cannulated screw fixation
   • B) Dynamic hip screw
   • C) Cemented hemiarthroplasty
   • D) Cemented total hip arthroplasty ✓
   • E) Conservative management
   • Answer: D. Per NICE guidelines, THA is indicated for displaced intracapsular fractures in patients who are independently mobile and cognitively intact. [5,9]

2. Q: What is the most important blood vessel compromised in displaced intracapsular femoral neck fractures leading to avascular necrosis?

   • A) Lateral femoral circumflex artery
   • B) Medial femoral circumflex artery ✓
   • C) Obturator artery (ligamentum teres)
   • D) Profunda femoris artery
   • E) Inferior gluteal artery
   • Answer: B. The medial femoral circumflex artery (MFCA) provides 80-90% of femoral head blood supply via retinacular vessels. [2]

3. Q: A 72-year-old man undergoes DHS fixation for an intertrochanteric fracture. What is the maximum acceptable tip-apex distance (TAD) to minimize cut-out risk?

   • A) 15 mm
   • B) 20 mm
   • C) 25 mm ✓
   • D) 30 mm
   • E) 35 mm
   • Answer: C. TAD > 25 mm increases cut-out risk 6-fold. TAD is the sum of AP and lateral screw tip to femoral head apex distances. [19]

4. Q: A 65-year-old woman has an undisplaced intracapsular fracture (Garden II) identified on MRI (normal X-ray). What is the most appropriate management?

   • A) Conservative with protected weight-bearing
   • B) Hemiarthroplasty
   • C) Total hip arthroplasty
   • D) Cannulated screw fixation ✓
   • E) Dynamic hip screw
   • Answer: D. Undisplaced intracapsular fractures should be fixed urgently to prevent displacement (10-15% risk) and AVN. Cannulated screws are standard. [3,13]

5. Q: Which electrolyte abnormality is most commonly associated with a "long lie" following a hip fracture?

   • A) Hyponatremia
   • B) Hypocalcemia
   • C) Hyperkalemia ✓
   • D) Hypomagnesemia
   • E) Hypophosphatemia
   • Answer: C. Rhabdomyolysis from prolonged immobilization releases intracellular potassium, causing hyperkalemia. Acute kidney injury may also occur from myoglobinuria. Hyponatremia is also common (dehydration-induced ADH).

6. Q: What is the recommended duration of pharmacological VTE prophylaxis following hip fracture surgery?

   • A) 7 days
   • B) 14 days
   • C) 28-35 days ✓
   • D) 6 weeks
   • E) 12 weeks
   • Answer: C. Extended prophylaxis (28-35 days) reduces symptomatic VTE by 62% compared to 7-10 days without increased bleeding. [14]

7. Q: A 55-year-old woman has a displaced intracapsular fracture (Garden IV) after a fall. What is the approximate risk of avascular necrosis if treated with cannulated screw fixation?

   • A) less than 5%
   • B) 10-15%
   • C) 25-50%
   • D) 50-80% ✓
   • E) > 90%
   • Answer: D. Garden IV fractures have 50-80% AVN risk due to complete disruption of retinacular vessels. This is why arthroplasty is preferred in elderly patients. [15]

8. Q: Which surgical approach for hip arthroplasty has the LOWEST dislocation rate?

   • A) Posterior (Moore)
   • B) Anterolateral (Hardinge) ✓
   • C) Direct anterior
   • D) Direct lateral (Kocher-Langenbeck)
   • E) Transtrochanteric
   • Answer: B. Anterolateral (Hardinge) approach has lower dislocation risk (1-2%) vs. posterior (2-4%), but may cause abductor damage (Trendelenburg gait 5-10%). Direct anterior also has low dislocation but higher wound complications.

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13.2 Viva Voce Scenarios

Viva Opening Statement

Examiner: "Tell me about hip fractures in the elderly."

Model Answer:
"Hip fractures are a major public health problem affecting 1.6 million people globally each year, with incidence projected to triple by 2050. They predominantly affect elderly patients with underlying osteoporosis following low-energy falls, though younger patients can sustain hip fractures from high-energy trauma.

The key anatomical distinction is between intracapsular fractures (involving the femoral neck within the hip capsule) and extracapsular fractures (intertrochanteric or subtrochanteric). This distinction is critical because intracapsular fractures disrupt the retinacular blood supply from the medial femoral circumflex artery, leading to high rates of avascular necrosis—10-30% overall, rising to 50-80% in displaced fractures.

For intracapsular fractures, the Garden classification (Stages I-IV) stratifies displacement and AVN risk. Displaced fractures (Garden III/IV) in the elderly are typically treated with arthroplasty—hemiarthroplasty for limited mobility patients or total hip arthroplasty for those who are independently mobile and cognitively intact, as demonstrated by the HEALTH trial. Undisplaced fractures (Garden I/II) are treated with internal fixation using cannulated screws or DHS.

Extracapsular fractures have robust healing potential due to metaphyseal vascularity and are classified by stability. Stable intertrochanteric fractures are treated with dynamic hip screw, while unstable patterns and subtrochanteric fractures require cephalomedullary nailing.

Mortality is substantial—8-10% at 30 days and 25-30% at 1 year—making hip fractures more lethal than many common cancers. Surgery within 36-48 hours is mandated by national guidelines to reduce mortality, complications, and length of stay. Post-operatively, orthogeriatric co-management and secondary fracture prevention with bisphosphonates are essential but tragically underutilized, with a treatment gap exceeding 70%." [1,2,5,9,12]

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Structured Viva Questions and Model Answers

Q1: "How would you classify intracapsular femoral neck fractures?"

Answer:
"I would use the Garden classification, which categorizes intracapsular fractures into four stages based on displacement and trabecular alignment on AP radiographs:

• Garden I: Incomplete or valgus-impacted fracture. The fracture line is visible, but the femoral head is tilted into valgus. These are stable with less than 5% AVN risk. Treatment is internal fixation with cannulated screws.

• Garden II: Complete but undisplaced fracture. The fracture line is complete, but the trabeculae remain aligned. These are potentially unstable (10-15% risk of secondary displacement) with 10-15% AVN risk. Treatment is urgent internal fixation.

• Garden III: Complete fracture with partial displacement. There is varus angulation and partial trabecular malalignment. These are unstable with 25-50% AVN risk. In elderly patients, treatment is typically arthroplasty.

• Garden IV: Complete fracture with full displacement. There is no bony contact and complete discontinuity of trabeculae. These are unstable with 50-80% AVN risk. Treatment in the elderly is arthroplasty (hemiarthroplasty or THA).

In practice, the Garden classification is often simplified to undisplaced (I/II) versus displaced (III/IV), as this drives the primary surgical decision: fixation versus arthroplasty.

I should also mention the Pauwels classification, which is based on the angle of the fracture line to the horizontal. Higher Pauwels angles (> 50°, Type III) indicate predominant shear forces and are associated with higher fixation failure rates, often favoring arthroplasty even in younger patients." [3]

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Q2: "A 75-year-old woman has a displaced intracapsular fracture. She walks independently with a stick, has mild cognitive impairment (AMTS 7/10), and lives alone. What are her surgical options, and which would you choose?"

Answer:
"The two main surgical options for a displaced intracapsular fracture in an elderly patient are hemiarthroplasty and total hip arthroplasty (THA).

Hemiarthroplasty replaces only the femoral head, preserving the native acetabulum. It is appropriate for patients with limited pre-injury mobility, cognitive impairment (where dislocation risk from THA is a concern), or lower functional demand.

Total hip arthroplasty replaces both the femoral head and acetabulum. Per NICE guidelines, THA is recommended for patients who were able to walk independently (with or without a stick) and are not cognitively impaired. The HEALTH trial showed that THA provides better long-term hip function and quality of life compared to hemiarthroplasty, with similar complication rates.

In this case, the patient walks independently with a stick, which meets NICE criteria for consideration of THA. However, she has mild cognitive impairment (AMTS 7/10—abnormal is less than 8), which increases her risk of post-operative dislocation with THA (mechanism-related confusion, non-compliance with hip precautions). She also lives alone, which may limit her ability to manage THA hip precautions.

My decision would lean toward cemented hemiarthroplasty due to her cognitive impairment and social situation, accepting that her functional outcome may be marginally lower than THA, but with lower dislocation risk (2-3% vs. 5-7% in cognitively impaired patients). I would use a cemented prosthesis, as the WHITE-5 trial demonstrated better quality of life, lower periprosthetic fracture risk, and lower mortality compared to uncemented. I might also consider a dual mobility bearing to further reduce dislocation risk if available.

However, if her cognitive impairment is truly mild and she has good family support, I would discuss the option of THA with her and her family, as she may benefit from the superior long-term function." [5,9,18]

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Q3: "What is tip-apex distance, and why is it important?"

Answer:
"The tip-apex distance (TAD) is a radiographic measurement used to predict the risk of screw cut-out following dynamic hip screw (DHS) or cannulated screw fixation for hip fractures. It was described by Baumgaertner in 1995 and is calculated as the sum of the distances from the tip of the lag screw to the apex of the femoral head on both the AP and lateral radiographs, after correcting for magnification.

The critical threshold is TAD ≤25 mm. When the TAD exceeds 25 mm, the risk of screw cut-out increases 6-fold (from approximately 2% to 12%). This is because a screw positioned peripherally has less purchase in the femoral head, particularly in osteoporotic bone, and is more likely to migrate under cyclic loading.

The ideal screw position is central-central or inferior-central on AP and lateral views, placing it in the densest trabecular bone and maximizing the distance to the articular surface. Some surgeons prefer inferior positioning on the AP view to maximize calcar support, but this increases the risk of inferior perforation if not carefully judged.

In practice, I would ensure intra-operative fluoroscopy confirms TAD less than 25 mm before completing the fixation. If the initial screw position results in TAD > 25 mm, I would reposition the guide wire and re-drill to achieve optimal placement. This is one of the most modifiable technical factors that directly impacts patient outcomes." [19]

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Q4: "What are the components of orthogeriatric co-management, and what is the evidence for its effectiveness?"

Answer:
"Orthogeriatric co-management is a multidisciplinary model of care where orthopedic surgeons and geriatricians jointly manage hip fracture patients, addressing both the fracture and the underlying medical, functional, and social vulnerabilities. The key components include:

1. Daily geriatric input: Geriatrician-led ward rounds to optimize medical comorbidities (cardiac, respiratory, renal, cognitive).
2. Delirium prevention and management: Orientation, sleep hygiene, minimizing opioids, treating underlying causes.
3. Early mobilization: Physiotherapy within 24 hours post-operatively; progressive weight-bearing.
4. Nutritional support: Protein supplementation (1.2 g/kg/day), correction of vitamin D deficiency.
5. VTE prophylaxis: Mechanical (TED stockings, IPC) and pharmacological (LMWH or DOACs) for 28-35 days.
6. Secondary fracture prevention: Bisphosphonate initiation, calcium and vitamin D supplementation, DEXA scanning.
7. Falls risk assessment: Multifactorial assessment (vision, medications, environment, gait/balance); targeted interventions.
8. Discharge planning: MDT assessment (PT, OT, social work); home modifications; outpatient follow-up.

Evidence:
The landmark Norwegian Hip Fracture Trial (Prestmo et al., Lancet 2015) randomized 397 patients to comprehensive geriatric care versus orthopedic care. The geriatric care group had:

• Better mobility at 4 months (49% vs. 36% returned to pre-fracture level; p=0.02).
• Shorter length of stay (median 11 vs. 15 days; pless than 0.001).
• Lower rate of institutional care (37% vs. 50%; p=0.02).

Meta-analyses confirm orthogeriatric co-management reduces:

• 30-day mortality by 20-40% (RR 0.60-0.80).
• Length of stay by 1.5-3 days.
• Major medical complications (pneumonia, delirium, pressure ulcers) by 30-50%.

It is now the standard of care mandated by NICE and the British Orthopaedic Association (BOA) Blue Book." [5,7,8]

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Q5: "Why do we give extended VTE prophylaxis for 28-35 days, and what are the options?"

Answer:
"Hip fracture patients are at extremely high risk for venous thromboembolism (VTE) due to:

1. Immobility pre- and post-operatively.
2. Fracture-induced hypercoagulability (systemic inflammatory response).
3. Advanced age and comorbidities.
4. Surgical trauma activating the coagulation cascade.

Without prophylaxis, the DVT rate is 40-60%, and symptomatic PE occurs in 2-10%, with PE accounting for 10-20% of 30-day deaths.

Duration: The VTE risk remains elevated for 12 weeks post-fracture, with peak symptomatic VTE at 2-6 weeks. Extended prophylaxis for 28-35 days (vs. 7-10 days) reduces symptomatic VTE by 62% (RR 0.38, 95% CI 0.24-0.61) without increasing major bleeding. This is supported by multiple RCTs and is recommended by NICE, AAOS, and ACCP guidelines.

Options:

1. LMWH (e.g., enoxaparin 40 mg SC OD): First-line. Predictable efficacy, 50-60% VTE reduction. Requires renal dose adjustment if CrCl less than 30.

2. DOACs (e.g., apixaban 2.5 mg BD or rivaroxaban 10 mg OD): Non-inferior to LMWH; oral administration improves adherence. Caution in renal impairment and drug interactions.

3. Fondaparinux (2.5 mg SC OD): Factor Xa inhibitor; alternative to LMWH. No HIT risk. Contraindicated if CrCl less than 30 (long half-life).

4. Aspirin (75-150 mg OD): Less effective than LMWH/DOACs (30-40% relative reduction vs. 50-60%). Reserved for patients with contraindications to anticoagulation (active bleeding, severe thrombocytopenia).

Timing: Start 6-12 hours post-operatively (after hemostasis confirmed) to avoid surgical bleeding and allow for spinal anesthesia (must be > 12 hours post-neuraxial block).

Mechanical prophylaxis: TED stockings and IPC are adjuncts—reduce DVT by 60% when combined with pharmacological prophylaxis." [14,22]

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13.3 Common Mistakes That Fail Candidates

❌ Mistake 1: Recommending conservative management for an undisplaced intracapsular fracture.

• Why it fails: Undisplaced fractures (Garden I/II) have a 10-15% risk of secondary displacement if not fixed, leading to AVN and worse outcomes. Urgent internal fixation is mandatory unless the patient is truly moribund.

❌ Mistake 2: Ordering CT as the first-line investigation for suspected occult fracture.

• Why it fails: MRI is the gold standard for occult hip fractures (sensitivity 99%, specificity 99%), not CT. CT has lower sensitivity (85-90%) for non-displaced fractures and misses bone marrow edema.

❌ Mistake 3: Delaying surgery to "fully optimize" stable medical conditions (e.g., correcting INR of 1.8).

• Why it fails: Delays beyond 36-48 hours significantly increase mortality (OR 1.41). Minor INR elevations (1.5-2.0) do not contraindicate surgery; reversal can be achieved peri-operatively if needed. The mantra is "parallel, not serial optimization"—optimize while preparing for surgery, don't delay unnecessarily.

❌ Mistake 4: Using PRN ("as needed") analgesia in elderly hip fracture patients.

• Why it fails: Elderly patients often underreport pain or have cognitive impairment. PRN dosing leads to inadequate pain control, increased delirium, and poor mobilization. Regular dosing (paracetamol 1g QDS) is essential.

❌ Mistake 5: Not knowing that hemiarthroplasty should be CEMENTED.

• Why it fails: The WHITE-5 trial definitively showed cemented hemiarthroplasty is superior to uncemented (better QoL, lower periprosthetic fracture, lower mortality). Saying "uncemented" is outdated practice and will fail you in vivas.

❌ Mistake 6: Confusing indications for DHS versus intramedullary nail.

• Why it fails: DHS is for stable intertrochanteric fractures (intact lateral cortex, no subtrochanteric extension). IM nail is for unstable fractures (reverse oblique, subtrochanteric extension). Mixing these up shows lack of understanding of biomechanics.

❌ Mistake 7: Failing to mention secondary fracture prevention (bisphosphonates).

• Why it fails: Hip fracture is a sentinel event for osteoporosis. Failing to address osteoporosis treatment shows you only treat the fracture, not the patient. Examiners expect you to mention FLS (Fracture Liaison Service), bisphosphonates, and the treatment gap.

❌ Mistake 8: Saying AVN can be treated with core decompression in post-traumatic AVN.

• Why it fails: Core decompression has less than 30% success in post-traumatic AVN (vs. 60-70% in atraumatic AVN like steroid-induced). Once AVN is established post-fracture, arthroplasty is the definitive treatment.

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13.4 High-Yield Facts for Vivas

• Garden classification: I (incomplete), II (undisplaced), III (partial displacement), IV (full displacement). Correlates with AVN risk (5% → 15% → 50% → 80%).

• Blood supply: Medial femoral circumflex artery → retinacular vessels → femoral head (80-90%); ligamentum teres artery (5-15%, inadequate alone).

• TAD: Tip-apex distance; must be less than 25 mm to prevent cut-out (6-fold increased risk if > 25 mm).

• HEALTH trial: THA vs. hemiarthroplasty; no difference in re-operation, but THA better QoL in mobile, cognitively intact patients.

• WHITE-5 trial: Cemented > uncemented hemiarthroplasty (better QoL, lower periprosthetic fracture, lower mortality).

• Surgery timing: less than 36-48 hours reduces mortality by 19-41% (OR 0.81, 95% CI 0.68-0.96).

• VTE prophylaxis: LMWH (enoxaparin 40 mg SC OD) for 28-35 days (not 7-10 days). Extended prophylaxis reduces VTE by 62%.

• Bisphosphonates: Reduce subsequent fractures by 40-50%; reduce mortality by 28% (HORIZON trial, zoledronic acid).

• Mortality: 30-day 8-10%; 1-year 25-30%. Higher in males, delayed surgery, ASA IV-V.

• Orthogeriatric care: Reduces mortality by 20-40%, LOS by 1.5-3 days, complications by 30-50%.

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Last Reviewed: 2026-01-02 | MedVellum Editorial Team

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Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists and current guidelines.