Acetabular Fracture (Adult)

1. Anatomy

1.1 Overview of the Acetabulum

The acetabulum represents one of the most architecturally sophisticated structures in the human skeleton, serving as the socket component of the hip joint. The term "acetabulum" derives from the Latin word for "vinegar cup" (acetum = vinegar), reflecting its concave morphology that ancient anatomists observed during dissection. This hemispherical cavity provides approximately 170-180 degrees of coverage for the femoral head, creating the deepest and most inherently stable ball-and-socket joint in the body. [1,2]

The acetabulum is formed by the confluence of three primary ossification centers corresponding to the ilium, ischium, and pubis. These three bones meet at a Y-shaped cartilaginous junction known as the triradiate cartilage, which ossifies and fuses between ages 14-16 years. The position where these three bones converge represents the structural epicenter of the acetabulum and is critical to understanding fracture patterns. [3]

Understanding acetabular anatomy requires appreciation of multiple interconnected concepts:

• Bony architecture: The columnar support system
• Articular surface: The lunate cartilage and fossa acetabuli
• Soft tissue structures: Labrum, ligamentum teres, and capsule
• Neurovascular relationships: Critical structures at risk during surgery
• Biomechanical function: Load transmission patterns

1.2 The Two-Column Concept

1.2.1 Judet and Letournel's Revolutionary Framework

The foundational understanding of acetabular anatomy was established by Robert Judet and Émile Letournel in 1964, who described the acetabulum as an inverted Y-shaped structure supported by two columns of bone. This conceptualization remains the cornerstone of acetabular fracture classification and surgical planning. [4]

The Anterior Column (Iliopubic Column):

• Extends from the iliac crest to the symphysis pubis
• Comprises the anterior half of the iliac wing
• Includes the pelvic brim (arcuate line)
• Encompasses the anterior wall of the acetabulum
• Contains the superior pubic ramus
• Provides anterior structural support for the acetabulum

The anterior column can be visualized as extending from approximately 2 cm posterior to the anterior superior iliac spine (ASIS), coursing through the acetabulum, and terminating at the pubic symphysis. On plain radiographs, this column is represented by the iliopectineal line (also called the iliopubic line).

The Posterior Column (Ilioischial Column):

• Extends from the superior aspect of the greater sciatic notch to the ischial tuberosity
• Comprises the posterior half of the iliac wing
• Includes the posterior wall of the acetabulum
• Encompasses the entire ischium
• Contains the ischial spine
• Provides posterior structural support and attachment for major ligaments

The posterior column is visualized on radiographs by the ilioischial line, which represents the posterior extent of the quadrilateral surface.

1.2.2 The Acetabular Dome (Roof)

The weight-bearing dome represents the most critical portion of the acetabulum from a functional standpoint. Defined by Letournel as the area of the acetabulum that supports the femoral head when the patient is standing erect, the dome comprises the superior 10-15 mm of the articular surface. [5]

Rowe's Arc Measurements:

• Matta refined the concept of the weight-bearing dome using roof arc measurements
• Medial roof arc: measured on AP radiograph from vertical line through acetabular center to fracture line
• Anterior roof arc: measured on obturator oblique view
• Posterior roof arc: measured on iliac oblique view
• Critical threshold: fractures with all three roof arcs > 45° may be amenable to conservative management

The "10mm Rule":

• Subchondral bone in the weight-bearing dome must have less than 2mm step-off after reduction
• The superior 10mm of articular surface bears the majority of hip joint forces
• Displacement in this zone correlates strongly with development of post-traumatic osteoarthritis

1.3 Walls Versus Columns

1.3.1 Anatomical Distinction

The walls of the acetabulum represent the true articular surfaces that directly contact the femoral head, while the columns represent the supporting buttresses of bone. This distinction is crucial for understanding fracture patterns and surgical approaches.

Anterior Wall:

• Represents the anterior articular surface of the acetabulum
• Bounded superiorly by the anterior inferior iliac spine (AIIS)
• Extends inferiorly to the anterior horn of the lunate surface
• Provides anterior coverage and prevents anterior femoral head dislocation
• Thickness ranges from 3-8mm
• Can be fractured independently (isolated anterior wall fracture) or as part of anterior column injury

Posterior Wall:

• Represents the posterior articular surface of the acetabulum
• Most commonly fractured component of the acetabulum
• Provides posterior stability against femoral head subluxation/dislocation
• Contains approximately 40% of the articular surface
• Critical for hip stability, especially in flexion
• Marginal impaction of the posterior wall is a common associated injury

Key Clinical Distinction:

• Column fractures extend from the pelvic brim to the obturator foramen (or beyond)
• Wall fractures are confined to the acetabular rim and adjacent articular surface
• The posterior column includes the posterior wall, but the posterior wall can be fractured in isolation

1.4 The Acetabular Labrum

1.4.1 Gross Anatomy

The acetabular labrum is a fibrocartilaginous ring that attaches to the bony rim of the acetabulum, deepening the socket by approximately 21% and increasing surface area by 28%. This structure is critical for hip stability, joint lubrication, and load distribution. [6]

Structural Characteristics:

• Triangular in cross-section with three surfaces: articular, peripheral, and basal
• Width varies from 6-8mm anteriorly to 8-12mm posteriorly
• Thickness approximately 4-6mm
• Attaches via a transitional zone of calcified cartilage at the acetabular rim
• Inferiorly, the labrum becomes continuous with the transverse acetabular ligament

Regional Variations:

• Anterior labrum: Thinner, more vascular, often implicated in femoroacetabular impingement
• Superior labrum: Bears significant load, relatively avascular central zone
• Posterior labrum: Thicker, provides posterior stability
• Inferior labrum (transverse ligament): Bridging structure across the acetabular notch

1.4.2 Function and Clinical Relevance

Functions of the Labrum:

1. Deepens the acetabulum: Increases coverage of femoral head by 21%
2. Creates a suction seal: Maintains negative intra-articular pressure
3. Distributes synovial fluid: Facilitates joint lubrication
4. Load distribution: Reduces peak contact stresses on articular cartilage
5. Proprioception: Contains mechanoreceptors contributing to joint position sense

Relevance in Acetabular Fractures:

• Labral tears frequently accompany acetabular fractures
• Entrapped labral tissue can prevent anatomical reduction
• Labral integrity affects long-term outcomes after fracture fixation
• Intra-articular fragments often lodge adjacent to the labrum

1.5 Articular Cartilage and the Lunate Surface

1.5.1 The Lunate Surface (Facies Lunata)

The acetabular articular cartilage is arranged in a characteristic horseshoe or crescent shape, hence the term lunate surface (Latin: luna = moon). This surface is not a complete hemisphere but rather an incomplete ring with several distinct zones:

Morphological Characteristics:

• Width: 15-25mm, widest superiorly
• Thickness: 1.5-3mm, thickest centrally (in contrast to femoral head)
• Surface area: Approximately 16 cm²
• Coverage: Provides 170° of anterior-posterior coverage

Three Distinct Horns:

1. Anterior horn: Thinner articular surface, adjacent to anterior wall
2. Superior dome: Thickest cartilage, weight-bearing region
3. Posterior horn: Moderate thickness, frequently involved in posterior wall fractures

Composition:

• Type II collagen predominant (90-95% of collagen content)
• Proteoglycans (aggrecan) provide compressive resistance
• Water content approximately 70-80%
• Chondrocytes arranged in zones: superficial, transitional, deep, calcified

1.5.2 The Acetabular Fossa (Fossa Acetabuli)

The cotyloid fossa (or acetabular fossa) is the non-articular central depression within the acetabulum:

Characteristics:

• Filled with fibrofatty tissue (pulvinar)
• Contains the acetabular branch of the obturator artery
• Attachment site for the ligamentum teres
• Covered by synovial membrane, not articular cartilage
• Does not participate in weight-bearing

Surgical Significance:

• Provides a "safe zone" for hardware placement (central acetabular screws)
• Marginal impaction fragments may be reduced into this space
• Pulvinar can trap debris and hinder reduction

1.6 The Quadrilateral Surface (Plate)

1.6.1 Anatomical Description

The quadrilateral surface (or quadrilateral plate) is a thin, flat region of the medial wall of the acetabulum that forms part of the inner pelvic wall:

Boundaries:

• Superior: Arcuate line (pelvic brim)
• Inferior: Obturator groove and ischium
• Anterior: Obturator foramen
• Posterior: Greater sciatic notch

Characteristics:

• Extremely thin cortical bone (2-4mm in some regions)
• Provides the medial wall of the acetabulum
• Visible on obturator oblique radiograph
• Medial displacement indicates central acetabular fracture or protrusion

1.6.2 Clinical and Surgical Relevance

Fracture Patterns:

• Medial subluxation of the femoral head often involves quadrilateral surface comminution
• Both-column fractures frequently demonstrate quadrilateral surface displacement
• Transverse and T-type fractures commonly affect this region

Surgical Considerations:

• Modified Stoppa approach provides excellent access for buttress plating
• Corona mortis vessels cross near the superior aspect
• Obturator neurovascular bundle lies immediately medial
• Buttress plating from the pelvic brim to the posterior column provides medial support

1.7 Supporting Ligamentous Structures

1.7.1 The Hip Joint Capsule

The fibrous capsule of the hip joint is the strongest and thickest of all synovial joint capsules, reflecting the stability requirements of this weight-bearing articulation:

Attachments:

• Acetabular attachment: Labral base and transverse acetabular ligament
• Femoral attachment: Anteriorly to intertrochanteric line, posteriorly to femoral neck (2/3 coverage)

Reinforcing Ligaments:

1. Iliofemoral Ligament (Y-ligament of Bigelow):

   • Strongest ligament in the human body
   • Origin: Anterior inferior iliac spine (AIIS)
   • Insertion: Intertrochanteric line (two bands: superior/inferior)
   • Function: Limits hip extension and external rotation
   • Tensile strength: > 750 N

2. Pubofemoral Ligament:

   • Origin: Iliopubic eminence and obturator crest
   • Insertion: Inferior intertrochanteric line
   • Function: Limits abduction and external rotation
   • Blends with medial iliofemoral ligament

3. Ischiofemoral Ligament:

   • Origin: Posterior acetabular rim and ischium
   • Insertion: Superior femoral neck (zona orbicularis)
   • Function: Limits internal rotation and adduction
   • Weakest of the three ligaments

4. Zona Orbicularis:

   • Circular band of fibers around the femoral neck
   • Creates a collar or "buttonhole" effect
   • Limits lateral translation of femoral head

1.7.2 The Ligamentum Teres (Ligament of the Head of Femur)

Anatomy:

• Origin: Transverse acetabular ligament and adjacent acetabular rim
• Insertion: Fovea capitis of the femoral head
• Length: Approximately 30-35mm
• Contains: Artery of the ligamentum teres (branch of obturator artery)

Function:

• Minimal mechanical role in adults (unlike pediatric population)
• Carries vascular supply in children (may contribute 20-30% of femoral head blood supply)
• Contains mechanoreceptors for proprioception
• May limit extreme ranges of motion

Clinical Relevance in Acetabular Fractures:

• Often disrupted in traumatic hip dislocations
• Avulsion of ligamentum teres can leave intra-articular fragments
• Artery contribution to femoral head is minimal in adults (1-2%)

1.8 Neurovascular Relationships

1.8.1 Arterial Supply

Primary Blood Supply to the Acetabulum:

1. Superior Gluteal Artery:

   • Branch of internal iliac artery
   • Exits pelvis through greater sciatic foramen (above piriformis)
   • Supplies iliac wing and superior acetabulum
   • At risk during posterior surgical approaches

2. Inferior Gluteal Artery:

   • Branch of internal iliac artery
   • Exits pelvis through greater sciatic foramen (below piriformis)
   • Supplies posterior column and ischium
   • At risk during posterior approaches

3. Obturator Artery:

   • Branch of internal iliac artery (usually)
   • Exits pelvis through obturator foramen
   • Provides acetabular branch through cotyloid notch
   • Gives rise to artery of ligamentum teres

4. Medial Femoral Circumflex Artery (MFCA):

   • Primary blood supply to femoral head
   • Must be protected during posterior approaches
   • Terminal branches at risk with posterior wall/column manipulation

Corona Mortis (Crown of Death):

• Aberrant vascular connection between obturator and external iliac/inferior epigastric systems
• Present in 10-30% of individuals (variable definitions)
• Located 4-8 cm from pubic symphysis along superior pubic ramus
• Major hemorrhage risk during anterior approaches and symphyseal plating
• Must be identified and ligated during ilioinguinal or Stoppa approaches

1.8.2 Venous Drainage

Pelvic Venous Plexus:

• Extensive venous network surrounds the acetabulum
• Communicates with femoral,

4. Clinical Presentation

4.1 History Taking Framework

4.1.1 Mechanism of Injury

High-Energy Mechanisms (> 90% of cases):

Low-Energy Mechanisms (less than 10% of cases):

4.1.2 Key Historical Questions

Immediate Injury Questions:

1. Exact mechanism: Position at time of impact (driver vs. passenger, knee position, hip flexion angle)
2. Direction of force: Determines likely fracture pattern
3. Ability to weight-bear immediately after injury: Suggests displacement severity
4. Numbness/tingling in leg or foot: Sciatic nerve involvement
5. Loss of bladder/bowel control: Sacral nerve root injury
6. Previous hip problems: Pre-existing arthritis, prior surgery

Pre-Hospital and Transfer Questions:

1. Time since injury: Critical for hip dislocation management (less than 6 hours optimal)
2. Reduction attempts: Prior closed reduction, traction applied
3. Blood loss: Hemodynamic status, transfusion requirements
4. Other injuries identified: Head, chest, abdominal, spinal

Past Medical History Relevance:

4.2 Symptom Profiles

4.2.1 Pain Characteristics

Typical Acetabular Fracture Pain:

• Location: Deep groin, lateral hip, buttock (dependent on fracture location)
• Quality: Severe, constant, aching with sharp exacerbations on movement
• Intensity: Typically 8-10/10 on numeric rating scale at presentation
• Radiation: Anterior thigh (L2-3 dermatomes), posterior thigh (sciatic distribution)
• Aggravating factors: Any hip motion, weight-bearing attempts, log-rolling
• Relieving factors: Immobilization, analgesia, traction

Pain Pattern by Fracture Type:

4.2.2 Functional Limitations

Immediate Functional Deficits:

1. Complete inability to weight-bear: Universal in displaced fractures
2. Unable to actively flex hip: Indicates significant injury severity
3. Unable to control limb position: Suggests neurological involvement
4. Incontinence: Red flag for sacral injury

Position of Comfort:

• Hip slightly flexed, externally rotated (reduces pressure on posterior structures)
• Avoidance of any active or passive hip motion
• Ipsilateral knee flexed to reduce sciatic nerve tension

4.3 Physical Examination

4.3.1 Primary Survey (ATLS)

Airway, Breathing, Circulation, Disability, Exposure:

• Acetabular fractures frequently occur in polytrauma patients
• Complete primary survey before focused musculoskeletal examination
• Hemorrhage control and resuscitation take priority
• Do not move patient excessively until spinal clearance

4.3.2 Inspection

Systematic Visual Assessment:

Morel-Lavallée Lesion Assessment:

• Closed degloving injury from shearing force
• Typically over greater trochanter or iliac crest
• Creates cavity filled with blood, lymph, necrotic fat
• May not be immediately apparent (develops over 24-48 hours)
• Fluctuant, mobile soft tissue mass
• Positive "fluid wave" on palpation
• Increases surgical site infection risk by 8-20x if unrecognized
• Requires aspiration, debridement, or drainage before ORIF

4.3.3 Palpation

Systematic Palpation Protocol:

1. Iliac crest: Tenderness suggests iliac wing fracture, sacroiliac disruption
2. ASIS and AIIS: Avulsion fracture sites, attachment points
3. Pubic symphysis: Instability suggests pelvic ring injury
4. Pubic rami: Fracture sites for anterior ring
5. Greater trochanter: Tenderness, crepitus, soft tissue swelling
6. Inguinal region: Femoral pulse assessment, hernia evaluation
7. Sacroiliac joints: Posterior ring stability assessment
8. Lumbar spine: Rule out associated spine injury

Pelvic Stability Testing (Single Assessment Only):

• Manual compression/distraction: Perform ONCE to assess stability
• Repeated testing causes additional bleeding and displacement
• Positive finding: Gross instability with minimal force
• Document clearly to prevent repeat testing by multiple examiners

4.3.4 Range of Motion Testing

Contraindications to ROM Testing:

• Known or suspected hip dislocation
• Grossly unstable fracture
• Hemodynamic instability
• Severe pain limiting examination

Modified ROM Assessment (When Safe):

• Passive motion only, within patient tolerance
• Assess for mechanical block (suggests interposed fragment)
• Note crepitus (indicates articular involvement)
• Compare to contralateral side

4.4 Neurological Examination

4.4.1 Sciatic Nerve Assessment

Critical Importance:

• Sciatic nerve palsy present in 10-40% of acetabular fractures
• Higher incidence with posterior wall/column fractures (up to 36%)
• Highest incidence with posterior hip dislocation (25-50%)
• Must be documented BEFORE any reduction attempts
• Complete vs. incomplete lesion affects prognosis dramatically

Peroneal Division (L4-S2) - Most Commonly Affected:

Tibial Division (L4-S3):

Documentation Requirements:

1. Pre-reduction neurological status
2. Post-reduction neurological status
3. Any change during hospitalization
4. Complete vs. incomplete lesion
5. Timing of onset (immediate vs. delayed suggests different mechanisms)

4.4.2 Femoral Nerve Assessment (L2-L4)

When to Suspect Femoral Nerve Injury:

• Anterior column/wall fractures
• Anterior hip dislocation
• Ilioinguinal approach planned or performed

4.4.3 Obturator Nerve Assessment (L2-L4)

4.4.4 Lumbosacral Plexus Assessment

Sacral Root Evaluation:

Red Flags for Cauda Equina/Conus Involvement:

• Urinary retention or incontinence
• Fecal incontinence
• Saddle anesthesia
• Absent bulbocavernosus reflex
• Bilateral lower extremity weakness

4.5 Vascular Examination

4.5.1 Arterial Assessment

Systematic Pulse Examination:

Signs of Vascular Injury:

1. Hard signs (require immediate intervention):

   • Absent distal pulses
   • Pulsatile hemorrhage
   • Expanding or pulsatile hematoma
   • Bruit or thrill over injury
   • Signs of limb ischemia (6 P's)

2. Soft signs (require further investigation):

   • Small, stable hematoma
   • Injury in proximity to major vessels
   • Diminished but palpable pulses
   • Unexplained hypotension

Ankle-Brachial Index (ABI):

• Calculate if any concern for vascular injury
• Normal: 0.9-1.3
• Abnormal: less than 0.9 requires further investigation
• Non-compressible: Suggests calcified vessels (common in diabetics)

4.5.2 Compartment Syndrome Assessment

Thigh Compartments at Risk:

• Anterior compartment (quadriceps)
• Posterior compartment (hamstrings)
• Medial compartment (adductors)

Clinical Signs:

1. Pain out of proportion to injury
2. Pain with passive stretch of involved muscles
3. Palpable tenseness of compartments
4. Paresthesias in involved nerve distributions
5. Paralysis (late sign)
6. Pulselessness (very late sign, unreliable)

Compartment Pressure Monitoring:

• Absolute pressure > 30 mmHg concerning
• Delta pressure (Diastolic BP - Compartment pressure) less than 30 mmHg indicates fasciotomy
• Continuous monitoring if clinical concern

4.6 Associated Injury Assessment

4.6.1 Hip Dislocation Assessment

Posterior Dislocation (> 90% of hip dislocations):

Anterior Dislocation (less than 10%):

10. Management

10.1 Emergency Department Management

Initial Resuscitation and Stabilization

Acetabular fractures frequently occur in the context of polytrauma, necessitating systematic Advanced Trauma Life Support (ATLS) evaluation before focused orthopaedic assessment.

Primary Survey Priorities:

Hemorrhage Control in Pelvic Trauma:

Acetabular fractures typically cause less hemorrhage than pelvic ring disruptions; however, associated injuries may produce significant bleeding:

Hip Dislocation Management

Hip dislocations associated with acetabular fractures require emergent reduction to minimize the risk of femoral head avascular necrosis (AVN) and sciatic nerve injury.

Time-Critical Reduction Protocol:

Closed Reduction Techniques:

Posterior Dislocation - Allis Maneuver:

1. Patient supine on stretcher or floor
2. Assistant stabilizes pelvis with downward pressure on ASIS
3. Hip and knee flexed to 90 degrees
4. Gentle longitudinal traction applied along femoral axis
5. Internal-to-external rotation with gentle adduction/abduction
6. Palpable or audible "clunk" indicates reduction
7. Immediate post-reduction imaging and neurovascular assessment

Anterior Dislocation - Reverse Allis/Stimson:

1. Patient supine with hip extended
2. Longitudinal traction with hip in extension
3. Gentle internal rotation and adduction
4. Alternative: lateral traction on proximal thigh

Post-Reduction Protocol:

Skin and Soft Tissue Assessment

Morel-Lavallée Lesion Management:

This closed degloving injury over the greater trochanter requires specific attention:

Surgical Timing Considerations:

10.2 Definitive Management Algorithm

┌─────────────────────────────────────────────────────────────────────────────────┐
│                        ACETABULAR FRACTURE MANAGEMENT                           │
│                              Decision Algorithm                                 │
└─────────────────────────────────────────────────────────────────────────────────┘
                                       │
                                       ▼
                    ┌──────────────────────────────────────┐
                    │     INITIAL ASSESSMENT (ED/Trauma)    │
                    │  • ATLS primary/secondary survey      │
                    │  • Hip dislocation? → Emergent reduce │
                    │  • Sciatic nerve function assessment  │
                    │  • Morel-Lavallée lesion evaluation   │
                    └──────────────────────────────────────┘
                                       │
                                       ▼
                    ┌──────────────────────────────────────┐
                    │         IMAGING ASSESSMENT            │
                    │  • AP pelvis + Judet views            │
                    │  • CT with 3D reconstruction          │
                    │  • Classify: Elementary vs Associated │
                    └──────────────────────────────────────┘
                                       │
                                       ▼
              ┌────────────────────────┴────────────────────────┐
              │                                                  │
              ▼                                                  ▼
   ┌──────────────────────┐                         ┌──────────────────────┐
   │   STABLE FRACTURE?   │                         │  UNSTABLE FRACTURE   │
   │ • Displacement less than 2mm  │                         │ • Displacement ≥2mm  │
   │ • Intact roof arc    │                         │ • Roof arc involved  │
   │ • Secondary lines OK │                         │ • Femoral sublux.    │
   └──────────────────────┘                         └──────────────────────┘
              │                                                  │
              ▼                                                  ▼
   ┌──────────────────────┐                         ┌──────────────────────┐
   │ PATIENT FACTORS      │                         │  SURGICAL CANDIDATE? │
   │ • Ambulatory status  │                         │                      │
   │ • Bone quality       │                         └──────────────────────┘
   │ • Medical comorbid.  │                                    │
   └──────────────────────┘                    ┌───────────────┴───────────────┐
              │                                │                               │
     ┌────────┴────────┐                       ▼                               ▼
     │                 │           ┌──────────────────────┐       ┌──────────────────────┐
     ▼                 ▼           │    YES - OPERATIVE   │       │   NO - HIGH RISK     │
┌──────────┐    ┌──────────────┐   │                      │       │                      │
│AMBULATORY│    │NON-AMBULATORY│   └──────────────────────┘       └──────────────────────┘
│ PATIENT  │    │  PATIENT     │              │                              │
└──────────┘    └──────────────┘              │                              ▼
     │                 │                       │                   ┌──────────────────────┐
     ▼                 ▼                       │                   │  NON-OPERATIVE RX    │
┌──────────────────────┐                       │                   │  • Protected WB      │
│  CONSERVATIVE Rx     │                       │                   │  • Skeletal traction │
│  • TDWB 6–12 weeks   │                       │                   │  • CONSIDER: Delayed │
│  • ROM exercises     │                       │                   │    THA if poor result│
│  • Serial imaging    │                       │                   └──────────────────────┘
└──────────────────────┘                       │
                                               ▼
                              ┌────────────────────────────────────┐
                              │         TIMING ASSESSMENT          │
                              │  • Optimal: Days 3–10              │
                              │  • Allows swelling resolution      │
                              │  • Enables surgical planning       │
                              └────────────────────────────────────┘
                                               │
                   ┌───────────────────────────┴───────────────────────────┐
                   │                           │                           │
                   ▼                           ▼                           ▼
      ┌────────────────────┐      ┌────────────────────┐      ┌────────────────────┐
      │ ANTERIOR COLUMN    │      │ POSTERIOR COLUMN   │      │ BOTH COLUMNS       │
      │ PATTERNS           │      │ PATTERNS           │      │ PATTERNS           │
      │                    │      │                    │      │                    │
      │ • Anterior wall    │      │ • Posterior wall   │      │ • Both column      │
      │ • Anterior column  │      │ • Posterior column │      │ • T-type           │
      │ • Ant col + PHT    │      │ • Post col + PW    │      │ • Transverse       │
      └────────────────────┘      └────────────────────┘      │ • Transverse + PW  │
                │                          │                   └────────────────────┘
                ▼                          ▼                            │
      ┌────────────────────┐      ┌────────────────────┐               │
      │ ANTERIOR APPROACH  │      │ POSTERIOR APPROACH │               ▼
      │                    │      │                    │      ┌────────────────────┐
      │ Options:           │      │ Options:           │      │ COMBINED/EXTENSILE │
      │ • Ilioinguinal     │      │ • Kocher-Langenbeck│      │ APPROACH           │
      │ • Modified Stoppa  │      │ • Extended K-L     │      │                    │
      │ • Intrapelvic AIP  │      │                    │      │ Options:           │
      │ • Pararectus       │      │                    │      │ • Extended ilio.   │
      └────────────────────┘      └────────────────────┘      │ • Simultaneous A+P │
                │                          │                   │ • Sequential staged│
                │                          │                   └────────────────────┘
                └──────────────────────────┼───────────────────────────┘
                                           │
                                           ▼
                              ┌────────────────────────────────────┐
                              │      REDUCTION & FIXATION          │
                              │  • Anatomic reduction goal (less than 2mm)  │
                              │  • Lag screws + neutralization     │
                              │  • Spring plates for comminution   │
                              │  • Buttress plating as needed      │
                              └────────────────────────────────────┘
                                           │
                                           ▼
                              ┌────────────────────────────────────┐
                              │    INTRAOPERATIVE ASSESSMENT       │
                              │  • Reduction quality (fluoroscopy) │
                              │  • Hardware position               │
                              │  • ROM assessment                  │
                              │  • Stability testing               │
                              └────────────────────────────────────┘
                                           │
                                           ▼
                              ┌────────────────────────────────────┐
                              │      POST-OPERATIVE PROTOCOL       │
                              │  • VTE prophylaxis                 │
                              │  • Protected weight bearing        │
                              │  • DVT screening                   │
                              │  • Heterotopic ossification proph. │
                              │  • Early ROM                       │
                              └────────────────────────────────────┘
                                           │
                                           ▼
                    ┌──────────────────────┴──────────────────────┐
                    │                                              │
                    ▼                                              ▼
       ┌────────────────────────┐                     ┌────────────────────────┐
       │  UNCOMPLICATED COURSE  │                     │    COMPLICATIONS       │
       │                        │                     │                        │
       │  • Progressive WB      │                     │  • Infection           │
       │  • ROM optimization    │                     │  • Non-union           │
       │  • Return to activity  │                     │  • AVN                 │
       │  • Serial imaging      │                     │  • PTOA               │
       │                        │                     │  • Nerve injury        │
       └────────────────────────┘                     └────────────────────────┘
                    │                                              │
                    ▼                                              ▼
       ┌────────────────────────┐                     ┌────────────────────────┐
       │   LONG-TERM FOLLOW-UP  │                     │  SALVAGE PROCEDURES    │
       │                        │                     │                        │
       │  • Annual radiographs  │                     │  • THA                 │
       │  • Activity counseling │                     │  • Revision ORIF       │
       │  • Arthritis screening │                     │  • Hip arthrodesis     │
       └────────────────────────┘                     │  • Resection arthropl. │
                                                      └────────────────────────┘

10.3 Conservative Management

Indications for Non-Operative Treatment

Conservative Management Protocol

Phase 1: Acute Phase (Weeks 0–2)

Phase 2: Early Rehabilitation (Weeks 2–6)

Phase 3: Progressive Weight Bearing (Weeks 6–12)

Phase 4: Return to Activity (Weeks 12+)

13. Clinical Cases

Case 1: Classic Posterior Wall Fracture with Hip Dislocation

Presentation: A 32-year-old male presents to the emergency department following a high-speed motor vehicle collision. He was the unrestrained driver and reports his knee struck the dashboard. He complains of severe left hip pain and is unable to move his leg.

Clinical Findings:

• Left lower extremity shortened, internally rotated, and adducted
• Unable to perform active hip movement
• Palpable posterior hip prominence
• Intact dorsalis pedis and posterior tibial pulses
• Critical finding: Unable to dorsiflex left ankle or extend great toe (sciatic nerve palsy)
• Sensation diminished in L5/S1 distribution

Imaging:

Management:

1. Emergent closed reduction within 45 minutes of arrival under procedural sedation
2. Post-reduction radiograph confirmed concentric reduction
3. CT scan post-reduction showed 35% posterior wall involvement with marginal impaction
4. Surgical planning: Kocher-Langenbeck approach with posterior wall fixation

Surgical Procedure:

• Kocher-Langenbeck approach with greater trochanteric flip osteotomy
• Marginal impaction elevated and bone grafted
• Posterior wall fixed with two 3.5mm reconstruction plates
• Intraoperative examination showed stable hip through full range of motion

Outcome:

• Sciatic nerve function began recovering at 6 weeks (tibialis anterior 2/5)
• 12-month follow-up: Complete nerve recovery, Harris Hip Score 92
• Matta radiographic grade: Excellent (anatomic reduction)
• Returned to work as construction worker at 6 months

Learning Points:

• Dashboard mechanism classically produces posterior wall/column injuries
• Emergent reduction is critical for femoral head viability and nerve recovery
• Post-reduction CT is mandatory to assess wall involvement and incarcerated fragments
• Sciatic nerve palsy often recovers with prompt reduction and anatomic fixation

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Case 2: Both-Column Fracture in Elderly Patient

Presentation: A 72-year-old female with osteoporosis and well-controlled hypertension presents after a fall from standing height onto her right side. She reports immediate right hip and groin pain and inability to bear weight.

Clinical Findings:

• Right lower extremity externally rotated
• Tenderness over greater trochanter and inguinal region
• Leg length discrepancy (2 cm shortening on right)
• Neurovascularly intact distally
• No evidence of skin compromise or degloving

Imaging:

Initial Assessment:

• Letournel Classification: Both-column fracture
• Secondary congruence present (femoral head maintaining relationship with fractured acetabular fragments)
• Osteoporotic bone quality noted on CT

Management Decision: Given:

• Age > 70 years
• Significant osteoporosis
• Secondary congruence present
• Intact roof arc measurements

Non-operative treatment selected:

Outcome:

• Fracture healed with secondary congruence maintained
• 6-month follow-up: Walking with single cane
• 2-year follow-up: Minimal symptoms, mild arthritic changes on radiograph
• Harris Hip Score: 78 (Fair, but appropriate for age and activity level)

Learning Points:

• Low-energy mechanisms can cause complex fractures in osteoporotic bone
• Both-column fractures with secondary congruence may be managed conservatively
• Age and bone quality are critical factors in treatment decision-making
• Acceptable outcomes possible with non-operative management in selected cases

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Case 3: Anterior Column + Posterior Hemitransverse Fracture

Presentation: A 45-year-old female motorcyclist presents after a lateral impact collision. She was wearing protective gear but sustained direct impact to her left hip. She complains of severe left hip pain radiating to the groin.

Clinical Findings:

• Left hip held in flexion with marked tenderness
• Unable to perform straight leg raise
• Ecchymosis developing over anterior thigh
• Morel-Lavallée lesion suspected: Fluctuant swelling over lateral thigh
• Neurovascularly intact

Imaging:

Pre-operative Management:

1. Skeletal traction (distal femoral pin, 15 lbs)
2. Morel-Lavallée lesion: Aspiration yielded 200 mL serosanguinous fluid
3. DVT prophylaxis with mechanical compression
4. Surgery delayed 5 days for soft tissue optimization

Surgical Procedure:

• Staged Morel-Lavallée debridement and drain placement
• Modified Stoppa approach for anterior column
• Lateral window for posterior hemitransverse visualization
• Reduction achieved with ball spike pusher and Jungbluth clamp
• Fixation: Infrapectineal plate + posterior column lag screw

Complications:

• Post-operative seroma at Morel-Lavallée site requiring two additional aspirations
• Resolved by 3 weeks post-surgery with compression dressing

Outcome:

• Anatomic reduction confirmed on post-operative CT
• 12-month follow-up: Harris Hip Score 88, returned to motorcycle riding
• No radiographic evidence of avascular necrosis or PTOA

Learning Points:

• Morel-Lavallée lesions require recognition and management before definitive surgery
• Associated column fractures benefit from combined approaches
• Modified Stoppa approach provides excellent anterior column access
• Soft tissue complications are common with degloving injuries

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Case 4: T-Type Fracture with Delayed Presentation

Presentation: A 58-year-old male presents 12 days after a fall from a 10-foot ladder. He was initially evaluated at an outside facility, diagnosed with "hip contusion," and sent home with pain medication. He now presents with persistent inability to bear weight and worsening pain.

Clinical Findings:

• Significant thigh and groin ecchymosis (resolving)
• Right lower extremity externally rotated
• Marked limitation of hip motion
• Neurovascularly intact
• No signs of skin compromise

Imaging:

Challenges:

1. Delayed presentation (12 days) with early callus
2. Significant displacement requiring ORIF
3. Increased surgical difficulty due to callus

Surgical Procedure:

• Combined Kocher-Langenbeck + Ilioinguinal approach (extensile)
• Extensive callus takedown required
• Femoral distractor used for reduction
• Posterior column plated through K-L, anterior column through ilioinguinal
• Intraoperative blood loss: 1,800 mL (cell saver used)

Outcome:

• Reduction: Matta grade "Satisfactory" (2 mm residual displacement)
• Prolonged recovery due to extensile approach
• 6-month: Developing heterotopic ossification (Brooker II)
• 2-year: Mild PTOA, Harris Hip Score 72

Learning Points:

• Acetabular fractures can be subtle on plain radiographs and require high index of suspicion
• Delayed surgery (> 14 days) significantly increases technical difficulty
• Extensile approaches increase blood loss and HO risk
• Imperfect reduction correlates with worse long-term outcomes

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Case 5: Posterior Column + Posterior Wall in Young Athlete

Presentation: A 24-year-old professional soccer player presents after an awkward landing during a match. He felt a "pop" in his hip and was unable to continue playing. He was transported directly from the field.

Clinical Findings:

• Left hip held in slight flexion and external rotation
• Severe pain with any attempted motion
• Tenderness over posterior hip
• Intact sciatic nerve function: Full strength in ankle dorsiflexion and plantarflexion
• No hip dislocation clinically

Imaging:

Patient Priorities:

• Return to professional sports
• Minimize surgical morbidity
• Preserve native hip

Surgical Strategy: Given young age, activity demands, and anatomic characteristics:

• Kocher-Langenbeck approach (standard, no extensile)
• Anatomic reduction mandatory for athletic return

Surgical Procedure:

• Standard Kocher-Langenbeck with piriformis-sparing modification
• Posterior column reduced first with ball spike pusher
• Column secured with 3.5mm reconstruction plate
• Posterior wall reduced and fixed with spring plate technique
• Intraoperative fluoroscopy confirmed anatomic reduction

Rehabilitation:

Outcome:

• Anatomic reduction achieved (Matta: Excellent)
• No complications
• Returned to full training at 5 months
• Returned to professional competition at 7 months
• 3-year follow-up: Harris Hip Score 100, no PTOA

Learning Points:

• Sports-related acetabular fractures can occur without dislocation
• Young, motivated patients with anatomic reduction can achieve excellent outcomes
• Piriformis-sparing techniques may reduce sciatic nerve morbidity
• Sport-specific rehabilitation is essential for athletic return

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14. Discharge Advice and Patient Information

Written Discharge Instructions Template

ACETABULAR (HIP SOCKET) FRACTURE Patient Discharge Information

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What is an acetabular fracture?

You have sustained a fracture of your acetabulum, which is the "socket" portion of your hip joint. This is a serious injury that requires careful management to ensure proper healing and the best possible long-term function of your hip.

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Surgical Patients: Post-operative Instructions

Wound Care:

Signs of Wound Infection (Contact us immediately if you notice):

• Increasing redness spreading from incision
• Warmth or swelling around the wound
• Pus or foul-smelling drainage
• Fever greater than 101.5°F (38.6°C)
• Increasing pain not controlled by medication

Activity Restrictions:

Mobility Equipment:

• Use your walker, crutches, or wheelchair as instructed
• Do not attempt to walk without assistive devices until cleared
• Ensure your home is safe (remove loose rugs, ensure adequate lighting)

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Blood Clot Prevention

You are at increased risk for blood clots in your legs (DVT) or lungs (PE) after this injury/surgery.

Medications:

• Take your blood thinner medication exactly as prescribed
• Common medications: Aspirin 81-325mg, Enoxaparin (Lovenox), Rivaroxaban (Xarelto), Apixaban (Eliquis)
• Do not skip doses

Warning Signs of Blood Clots:

Prevention Measures:

• Perform ankle pump exercises every hour while awake
• Wear compression stockings as instructed
• Stay well hydrated
• Avoid prolonged sitting (get up or shift position every 30-45 minutes)

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Pain Management

Medications:

Non-medication Pain Control:

• Ice packs (20 minutes on, 20 minutes off) around hip
• Position changes for comfort
• Relaxation techniques
• Gradual activity as tolerated

Important:

• Do not drink alcohol while taking narcotic pain medications
• Do not drive while taking narcotic pain medications
• Constipation is common with narcotics—take stool softeners

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Physical Therapy

Physical therapy is essential for your recovery. Your therapist will guide you through exercises to:

• Maintain joint motion
• Strengthen muscles around your hip
• Restore normal walking pattern
• Return to your regular activities

Home Exercises (perform 3 times daily):

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Follow-up Appointments

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**When to Seek Emergency Care (Call 911 or go to