DRUJ Injury & TFCC Tear

1. Clinical Overview

Summary

The Distal Radioulnar Joint (DRUJ) is the critical pivot point for forearm rotation, contributing approximately 150° of combined pronation-supination arc. Stability is provided by the Triangular Fibrocartilage Complex (TFCC), a sophisticated fibrocartilaginous structure that functions as both a load-bearing cushion and a stabilizer of the ulnocarpal articulation. The TFCC bears approximately 20% of axial load across the wrist, with this proportion increasing significantly in ulnar-positive variance states. [1,2]

The deep fibers of the TFCC (Ligamentum Subcruentum) attach to the fovea of the ulnar head, providing the primary stabilizing force against dorsopalmar translation of the DRUJ. Injuries range from acute traumatic tears (Palmer Class 1) to chronic degenerative conditions (Palmer Class 2). "Ulnar-sided wrist pain" represents one of the most challenging diagnostic scenarios in hand surgery—often described as the "low back pain" of the wrist due to its multifactorial etiology and chronic nature. [3,4]

A key biomechanical concept is ulnar variance: the relative length of the distal ulna compared to the distal radius. Patients with ulnar-positive variance (ulna longer than radius by ≥2mm) are predisposed to ulnar impaction syndrome, where repetitive axial loading causes the ulnar head to impinge against the lunate and triquetrum, leading to progressive TFCC degeneration, chondromalacia, and eventually lunotriquetral ligament attenuation. [5,6]

Management strategies are dictated by the Palmer classification, with peripheral tears (Class 1B foveal disruptions) amenable to arthroscopic repair, while central avascular tears (Class 1A) require debridement. Ulnar shortening osteotomy remains the definitive treatment for ulnar impaction syndrome with positive variance. [7,8]

Key Facts

• Anatomical Complexity: The ulnar side of the wrist represents a "black box" with overlapping pain generators including TFCC, lunotriquetral ligament, ECU tendon, ulnocarpal ligaments, and pisotriquetral joint.
• Mechanism of Injury:
  • Traumatic: Fall onto outstretched hand (FOOSH) with hyperpronation and ulnar deviation
  • Torsional: Power tool kickback, forced rotation during contact sports
  • Distraction: Sudden pulling force on extended wrist
  • Chronic overload: Racquet sports, gymnastics, weightlifting
• Vascular Anatomy (Critical Surgical Implication):
  • Peripheral 10-20%: Vascularized from ulnar artery branches. Capable of biological healing. Repairable.
  • Central 80%: Avascular fibrocartilaginous zone receiving nutrition via synovial diffusion. Does NOT heal. Requires debridement.
• Load Distribution: Normal wrist transfers 80% of axial load through radiocarpal joint, 20% through ulnocarpal joint via TFCC. Each 1mm of positive ulnar variance increases ulnocarpal load by 18%. [5]

Clinical Pearls

"The Fovea Sign": Apply firm pressure with the examining thumb into the soft spot located between the ulnar styloid and the FCU tendon, just distal to the ulnar head. Reproduction of deep, well-localized pain in this "foveal region" demonstrates 95% sensitivity and 87% specificity for foveal disruption of the TFCC (Palmer 1B injury—the surgically important subtype). [9]

"Piano Key vs Ballottement":

• Piano Key Sign: Gross dorsal instability where the entire ulnar head subluxates dorsally and can be depressed like a piano key. Seen in complete DRUJ disruption (Galeazzi fracture-dislocation, Essex-Lopresti injury).
• DRUJ Ballottement Test: Stabilize the distal radius with one hand. With the other hand, translate the ulnar head dorsally and volarly while assessing end-point quality. A "soft" or absent end-point compared to the contralateral wrist indicates TFCC insufficiency and DRUJ instability. Test in neutral, pronation, and supination—instability is typically maximal in neutral forearm rotation.

"Positive Variance Kills the Lunate": Ulnar-positive variance creates a pathological cascade known as the "ulnar impaction sequence." Progressive stages include TFCC central wear (Palmer 2A), lunate/triquetral chondromalacia (2B), TFCC perforation (2C), lunotriquetral ligament attenuation (2D), and ultimately ulnocarpal arthritis (2E). This is a mechanical problem requiring mechanical correction via ulnar shortening. [6]

"The TFCC Table Lift Test": Ask the patient to place both palms flat on a table and attempt to lift themselves up (pushing through extended wrists). Reproduction of ulnar-sided pain with this loading maneuver is highly predictive of Palmer 1B TFCC lesions. [10]

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2. Epidemiology

Demographics

• Incidence: TFCC injuries account for 3-9% of all wrist injuries presenting to emergency departments. [11]
• Age Distribution:
  • Traumatic tears (Palmer 1): Bimodal distribution
    • Peak 1: Young adults aged 20-35 years (sports, trauma)
    • Peak 2: Middle-aged adults 45-55 years (degenerative changes superimposed on acute injury)
  • Degenerative tears (Palmer 2): Progressive increase after age 30
    • 50% prevalence in asymptomatic individuals > 50 years (incidental finding on MRI)
    • 80% prevalence in cadaveric studies > 60 years [3]
• Sex: Male:Female ratio approximately 2:1 for traumatic injuries (sports and occupational trauma), 1:1 for degenerative conditions
• Occupational Risk:
  • Manual laborers: Carpenters, mechanics, assembly line workers
  • Athletes: Tennis, golf, gymnastics, baseball (pitchers), volleyball, hockey
  • Musicians: Percussionists, pianists (repetitive ulnar deviation and loading)

Anatomical Variance

• Ulnar Variance Distribution (Normal Population):
  • Neutral (±1mm): 60-70%
  • Positive (>+1mm): 20-25%
  • Negative (< -1mm): 10-15%
• Ulnar-positive variance increases TFCC tear risk by 4-fold and accelerates degenerative changes by 10-15 years. [5]

Associated Injuries

• Galeazzi Fracture-Dislocation: Radial shaft fracture with DRUJ disruption (10-15% of radial fractures)
• Distal Radius Fractures: TFCC injury in 35-50% of cases, particularly with ulnar styloid base fractures > 2mm displacement
• Essex-Lopresti Injury: Radial head fracture + interosseous membrane disruption + DRUJ instability (rare but devastating)

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3. Pathophysiology

Functional Anatomy: The TFCC

The TFCC is a complex, integrated ligamentous and fibrocartilaginous structure first comprehensively described by Palmer and Werner in 1981. It serves as the primary soft tissue stabilizer of the DRUJ and the main load-bearing structure of the ulnocarpal articulation. [1,2]

Six Principal Components:

1. Triangular Fibrocartilage (Articular Disc):

   • Central biconcave disc spanning from the ulnar border of the lunate fossa of the radius to the base of the ulnar styloid
   • Composed of fibrocartilage with randomly oriented collagen bundles
   • Central avascular zone (80% of surface area)
   • Peripheral vascular zone (10-20% of circumference)

2. Dorsal and Volar Radioulnar Ligaments (Primary DRUJ Stabilizers):

   • Volar Radioulnar Ligament: Tightest in supination, prevents dorsal translation of ulna
   • Dorsal Radioulnar Ligament: Tightest in pronation, prevents volar translation of ulna
   • Deep fibers insert into the fovea (medial to styloid base)—critical for stability
   • Superficial fibers insert into the styloid base—secondary stabilizers
   • The "ligamentum subcruentum" refers specifically to the deep foveal insertion

3. Meniscus Homologue:

   • Fibrofatty structure between ulnar styloid and triquetrum
   • Functions as a spacer and shock absorber

4. Ulnar Collateral Ligament: Reinforces ulnar border

5. Extensor Carpi Ulnaris (ECU) Tendon Sheath:

   • Floor of the 6th dorsal compartment
   • Subsheath acts as a stabilizer of the ulnar carpus

6. Ulnolunate and Ulnotriquetral Ligaments (Ulnocarpal Ligaments):

   • Volar ligaments providing carpal support
   • Bridge from TFCC to lunate and triquetrum

Biomechanical Function:

• Load Transmission: Transmits 20% of axial forearm load in neutral variance
• DRUJ Stability: Primary soft tissue stabilizer preventing radioulnar translation
• Forearm Rotation: Acts as a fulcrum allowing smooth pronation-supination through 150° arc
• Carpal Stabilization: Suspends the ulnar carpus via ulnocarpal ligaments

Blood Supply and Healing Potential

Critical concept for surgical decision-making: [3]

• Peripheral 10-20%: Supplied by:

  • Ulnar artery (dorsal and palmar branches)
  • Anterior interosseous artery (distal branches)
  • Viable repair zone—biological healing possible

• Central 80%: Avascular

  • Nutrition via synovial diffusion only
  • No healing capacity
  • Tears require debridement, not repair

This vascular anatomy directly informs the Palmer classification treatment algorithm.

Palmer Classification System

The gold standard classification system, published in 1989, remains the foundation of TFCC injury management. [1]

Class 1: Traumatic Lesions

• 1A - Central Perforation:

  • Location: Central avascular zone
  • Mechanism: Axial loading + wrist extension
  • Stability: DRUJ stable (radioulnar ligaments intact)
  • Treatment: Arthroscopic debridement

• 1B - Ulnar Avulsion (Foveal Tear):

  • Location: Foveal insertion of radioulnar ligaments
  • Mechanism: Forced hyperpronation or distraction
  • Stability: DRUJ unstable (loss of primary stabilizers)
  • Treatment: Arthroscopic or open repair (highest priority injury)
  • Subtypes (Atzei Classification): [13]
    • Proximal (foveal): Deep ligament disruption
    • Distal (styloid): Superficial ligament disruption
    • Combined: Both deep and superficial disruption

• 1C - Distal Avulsion:

  • Location: Ulnocarpal ligament attachment (ulnolunate, ulnotriquetral)
  • Mechanism: Distraction + ulnar deviation
  • Treatment: Debridement vs repair depending on stability

• 1D - Radial Avulsion:

  • Location: Sigmoid notch attachment
  • Mechanism: Uncommon, usually high-energy trauma
  • Treatment: Repair to radius (technically challenging)

Class 2: Degenerative Lesions (Ulnar Impaction Sequence)

Progressive stages of ulnocarpal impaction in ulnar-positive variance: [6]

• 2A: TFCC wear (fraying, thinning)
• 2B: + Lunate and/or ulnar head chondromalacia
• 2C: + TFCC perforation
• 2D: + Lunotriquetral ligament tear
• 2E: + Ulnocarpal arthritis

Treatment strategy shifts from debridement (2A-2C) to ulnar shortening osteotomy (2B-2D) to salvage procedures (2E).

Biomechanics of Ulnar Variance

Definition: The relative length difference between the distal articular surfaces of the radius and ulna, measured on a posteroanterior (PA) radiograph with the shoulder abducted 90°, elbow flexed 90°, and forearm in neutral rotation. [5]

Classification:

• Neutral: 0 ± 1mm (ulna and radius equal length)
• Positive: Ulna > 1mm longer than radius
• Negative: Ulna > 1mm shorter than radius

Clinical Significance:

• Each 1mm of positive ulnar variance increases ulnocarpal load by 18%
• +2.5mm variance doubles ulnocarpal load (40% vs 20%)
• This creates a mechanical overload → TFCC degeneration → ulnar impaction syndrome
• Negative variance decreases ulnocarpal load but increases risk of Kienbock's disease (lunate avascular necrosis)

Dynamic Variance:

• Pronation increases ulnar variance by 1-2mm (pushes ulna distally)
• Supination decreases ulnar variance by 1-2mm (retracts ulna proximally)
• Grip strength increases variance by 0.5-1mm
• This is why standardized positioning is critical for accurate measurement

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4. Clinical Presentation

Symptoms

• Pain:

  • Location: Ulnar side of wrist, typically dorsal-ulnar or volar-ulnar
  • Character: Deep, aching pain with sharp exacerbations on loading
  • Provocative activities:
    • Rotational: Turning doorknobs, using screwdrivers, wringing towels
    • Loading: Push-ups, rising from chair using armrests, carrying heavy bags
    • Ulnar deviation: Hammering, tennis backhand
  • Temporal pattern:
    • Acute tears: Sharp onset after specific trauma
    • Chronic tears: Insidious onset, progressive worsening over months

• Mechanical Symptoms:

  • Clicking/Clunking: Painful clicking with forearm rotation (particularly pronation-supination transition)
  • Locking: Rare, but when present suggests bucket-handle tear or loose body (urgent arthroscopy indication)
  • Instability: Sensation of wrist "giving way" or "shifting" (DRUJ instability)

• Functional Limitations:

  • Weakness: Reduced grip strength (typically 30-50% reduction compared to uninjured side)
  • Reduced Range: Painful limitation of pronation-supination, particularly end-range
  • Activity Modification: Inability to perform work or sport-specific tasks

Physical Examination

Inspection:

• Swelling: Dorsal-ulnar fullness
• Deformity: Dorsal prominence of ulnar head (DRUJ subluxation)
• Muscle wasting: Hypothenar atrophy in chronic cases

Palpation:

• Fovea Sign [9]:

  • Technique: Palpate between ulnar styloid and FCU tendon, just distal to ulnar head
  • Positive: Deep, well-localized tenderness
  • Significance: 95% sensitivity, 87% specificity for foveal disruption (Palmer 1B)

• Ulnar Styloid Tenderness: May indicate styloid fracture or superficial TFCC avulsion

• DRUJ Line Tenderness: Direct palpation over radioulnar joint line (dorsal)

• ECU Tendon: Palpate during pronation-supination to assess for subluxation

Provocative Tests:

• TFCC Compression (Grind) Test:

  • Technique: Axially load the wrist in ulnar deviation and passively rotate forearm
  • Positive: Reproduction of pain
  • Sensitivity: 95%, Specificity: 93% [11]

• DRUJ Ballottement (Stress) Test:

  • Technique: Stabilize radius with one hand, translate ulnar head dorsally and volarly with other hand
  • Assessment: Compare end-point to contralateral side
  • Positive: Soft end-point, excessive translation, pain
  • Test in neutral, pronation, and supination

• TFCC Table Lift Test [10]:

  • Technique: Patient places palms flat on table and attempts to lift body weight
  • Positive: Reproduction of ulnar-sided pain
  • Highly specific for Palmer 1B lesions

• Piano Key Sign:

  • Technique: Depress prominent ulnar head with forearm pronated
  • Positive: Ulnar head depresses and springs back
  • Indicates: Gross DRUJ instability (complete ligamentous disruption)

• Ulnocarpal Stress Test:

  • Technique: Ulnar deviation + axial load + pronation-supination
  • Positive: Pain over ulnar carpus
  • Indicates: Ulnar impaction syndrome

• Press Test:

  • Technique: Patient pushes up from chair using extended wrists
  • Positive: Ulnar-sided pain
  • Differential: TFCC tear vs lunotriquetral ligament injury

Range of Motion:

• Active and passive pronation-supination (normal: 75° pronation, 85° supination)
• Compare to contralateral side
• Note: Pain at end-range vs midrange
• Wrist flexion-extension, radial-ulnar deviation (assess for global stiffness)

Strength:

• Grip strength dynamometry (compare to contralateral)
• Pinch strength (key pinch, tip pinch)
• Typically 30-50% reduction with symptomatic TFCC tears

Neurovascular:

• Ulnar nerve: Tinel's at Guyon's canal, intrinsic muscle strength, sensory distribution
• Median nerve: Exclude carpal tunnel syndrome
• Radial artery and ulnar artery pulses

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5. Investigations

Plain Radiography

Standard Wrist Series:

• Posteroanterior (PA) View (Critical for ulnar variance measurement):

  • Standardized positioning: Shoulder 90° abduction, elbow 90° flexion, forearm neutral rotation
  • Measure ulnar variance: Difference between distal articular surfaces of radius and ulna
  • Assess for:
    • Ulnar styloid fracture (base fractures > 2mm displacement indicate TFCC injury)
    • DRUJ widening or overlap (instability)
    • Carpal alignment (exclude DISI/VISI patterns)
    • Lunate sclerosis (ulnar impaction)
    • Arthritis (ulnocarpal joint space narrowing)

• Lateral View:

  • Assess for DRUJ subluxation (compare radioulnar relationship to contralateral)
  • Carpal alignment (scapholunate angle, lunotriquetral angle)

• Pronated Grip View:

  • Increases ulnar variance by 1-2mm
  • May unmask dynamic ulnar impaction

Computed Tomography (CT):

• Indications:
  • Assessment of DRUJ incongruity
  • Evaluation of ulnar styloid fracture fragment size and displacement
  • Pre-operative planning for complex DRUJ reconstruction
  • 3D reconstructions for sigmoid notch morphology
• Technique: Bilateral comparison CT with forearm in neutral, pronation, and supination

Magnetic Resonance Imaging (MRI)

Standard MRI:

• Sensitivity: 70% for TFCC tears (operator and machine dependent)
• Specificity: 85-90%
• Best for:
  • Peripheral tears (higher signal on T2)
  • Associated injuries (lunotriquetral ligament, ECU tendon)
  • Bone marrow edema (ulnar impaction)

MR Arthrography (MRA):

• Gold standard non-invasive imaging modality
• Technique: Intra-articular injection of gadolinium contrast (radiocarpal, DRUJ, or both)
• Sensitivity: 90-95% [11]
• Specificity: 95%
• Findings:
  • Central perforation: Contrast leak through disc
  • Peripheral tear: Contrast extravasation at peripheral margin
  • Ligament avulsion: Contrast leak at foveal or styloid attachment
• Three-compartment injection: Radiocarpal + midcarpal + DRUJ for comprehensive assessment

MRI Findings in Ulnar Impaction Syndrome:

• TFCC degeneration or perforation
• Lunate and/or triquetral chondral changes
• Bone marrow edema in lunate, triquetrum, or ulnar head
• Lunotriquetral ligament attenuation or tear

Wrist Arthroscopy

The Diagnostic Gold Standard: [7,8]

• Most accurate method for TFCC tear diagnosis and classification
• Allows simultaneous diagnostic assessment and therapeutic intervention
• Sensitivity: 100%
• Specificity: 100%

Technique:

• Traction tower with 10-15 lbs longitudinal traction
• Standard portals:
  • 3-4 portal (between EPL and EDC): Primary viewing portal
  • 4-5 portal (radial to EDC): Primary working portal
  • 6R portal (radial to ECU): Visualization of ulnar structures
  • 6U portal (ulnar to ECU): DRUJ access, ulnar-sided work

Arthroscopic Classification:

• Palmer 1A: Central disc perforation, stable to probing
• Palmer 1B: Peripheral detachment (foveal), DRUJ unstable on probing, "trampoline test" positive (loss of tension)
• Palmer 1C: Distal avulsion (ulnocarpal ligaments)
• Palmer 1D: Radial avulsion

Arthroscopic Grading of Instability:

• Grade 1: Slight hemorrhage or softening of TFCC
• Grade 2: Fraying or partial tear
• Grade 3: Complete tear with DRUJ instability

Trampoline Test:

• Probe TFCC through 4-5 portal
• Normal: Firm, elastic rebound (trampoline effect)
• Abnormal: Loss of tension, excessive displacement, no rebound (positive test—indicates peripheral detachment)

Diagnostic/Therapeutic Injection

Indication:

• Equivocal imaging
• Differentiation between TFCC pain and other ulnar-sided pathology
• Temporary relief to guide surgical decision

Technique:

• Ultrasound or fluoroscopic guidance
• 1-2 mL local anesthetic (lidocaine or bupivacaine) + corticosteroid
• Injection sites:
  • DRUJ (between ulnar head and sigmoid notch)
  • Radiocarpal joint (may communicate with TFCC if perforated)
  • Foveal region (direct infiltration)

Interpretation:

• Significant pain relief (> 50% reduction) for 2-4 hours = positive test
• Confirms TFCC as pain generator
• Does not definitively diagnose tear type

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6. Management Algorithm

                         ULNAR SIDED WRIST PAIN
                                  ↓
                     HISTORY + PHYSICAL EXAMINATION
                                  ↓
                            PLAIN RADIOGRAPHS
                    (PA, Lateral, Pronated Grip Views)
                                  ↓
                 ┌────────────────┴────────────────┐
            TRAUMA HISTORY                    INSIDIOUS ONSET
         (Acute Fall, Twist)              (Chronic, Overuse)
                  ↓                                ↓
        CHECK DRUJ STABILITY              CHECK ULNAR VARIANCE
         (Ballottement Test)                   (PA X-Ray)
           ┌──────┴──────┐                 ┌──────┴──────┐
       STABLE          UNSTABLE       NEUTRAL/NEG    POSITIVE (+2mm)
          ↓                ↓                ↓              ↓
    Conservative      MRI/MRA        Conservative   ULNAR IMPACTION
    (Splint 4-6w)        ↓           (as above)       SYNDROME
    Physio/Rehab   Palmer 1B?                             ↓
          ↓          ┌────┴────┐                      MRI/MRA
    Review 6w     YES        NO                    ┌─────┴─────┐
    ┌────┴────┐    ↓          ↓                Palmer 2A-2C   2D-2E
  Improved  Failed  REPAIR   DEBRIDE                 ↓           ↓
     ↓        ↓    (Foveal) (Central)          CONSERVATIVE   Advanced
  Discharge  MRA      ↓          ↓              Trial 3-6m   (Arthritis)
                  Arthroscopic  Arthroscopic         ↓           ↓
                  Transosseous  Debridement    ┌─────┴─────┐  SALVAGE
                  Repair        (Palmer 1A)  Failed    Improved (Darrach/
                     ↓             ↓            ↓          ↓    Sauvé-
                  Muenster    Wrist Splint  SURGERY   Discharge Kapandji)
                  Splint 6w   3-4w              ↓
                     ↓            ↓         Ulnar Shortening
                  REHAB 3m     REHAB 6w    Osteotomy (USO)
                     ↓            ↓              ↓
                  RTP 4-6m    RTP 3-4m      OR
                                           Arthroscopic Wafer
                                                ↓
                                           REHAB 3-4m
                                                ↓
                                           RTP 4-6m

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7. Management Protocols

1. Conservative (Non-Operative) Management

Indications:

• Stable TFCC tears (Palmer 1A, 1C with normal DRUJ stability)
• Partial-thickness tears
• Degenerative tears (Palmer 2A-2C) without positive ulnar variance
• Patient refuses surgery
• Medical comorbidities precluding surgery

Protocol:

Phase 1: Immobilization (0-6 weeks)

• Wrist Splint: Neutral wrist position, forearm free (for stable injuries)
• Muenster Splint: Above-elbow splint restricting rotation (for borderline stable injuries)
• Duration: 4-6 weeks
• Activity modification: Avoid provocative activities (rotation, loading, ulnar deviation)

Phase 2: Range of Motion (6-8 weeks)

• Gentle active ROM exercises
• Progress pronation-supination gradually
• Pain-guided progression

Phase 3: Strengthening (8-12 weeks)

• Isometric wrist and forearm strengthening
• ECU Strengthening: Critical—ECU acts as a dynamic DRUJ stabilizer
• Proprioceptive training
• Gradual return to functional activities

Adjunctive Therapies:

• Corticosteroid Injection: DRUJ or foveal region injection for diagnostic and short-term therapeutic benefit
• NSAIDs: Oral anti-inflammatories for pain control (time-limited due to GI side effects)
• Activity Modification: Avoid high-load, rotational activities for 3-6 months

Success Rate:

• Stable tears: 60-70% good outcomes with conservative management
• Unstable tears: 20-30% (surgical referral recommended)

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2. Arthroscopic Debridement (Palmer 1A, 2A-2C)

Indications:

• Central TFCC perforation (Palmer 1A)—avascular zone
• Degenerative tears with normal ulnar variance (Palmer 2A-2C)
• Failed conservative management (3-6 months)
• Stable DRUJ on exam

Technique:

• Traction: 10-15 lbs
• Portals: 3-4, 4-5, 6R
• Debridement: Remove unstable, frayed edges using arthroscopic shaver and/or radiofrequency probe
• Principle: Trim back to stable peripheral rim (similar to meniscal debridement in knee)
• Preserve peripheral rim (vascular zone) to maintain stability
• Maximum safe debridement: 2/3 of central disc (preserve 1/3 peripheral rim)

Post-Operative:

• Wrist splint: 2 weeks (comfort)
• Early ROM: Start at 2 weeks
• Strengthening: Begin at 6 weeks
• Return to sport: 3-4 months

Outcomes:

• Good-excellent results: 70-85% at 2 years [7,19]
• Worse outcomes with positive ulnar variance (underlying impaction not addressed)

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3. Arthroscopic TFCC Repair (Palmer 1B, 1D)

Indications:

• Peripheral TFCC tear with DRUJ instability (Palmer 1B foveal disruption)
• Acute traumatic avulsion in young patients
• Failed conservative management with confirmed peripheral tear on MRA or arthroscopy
• Positive fovea sign with ballottement instability

Contraindications:

• Central avascular tear (Palmer 1A)—will not heal
• Advanced degenerative arthritis (Palmer 2E)
• Active infection

Surgical Techniques:

A. Arthroscopic Transosseous Repair (Most Common) [7,8,13,18]

• Technique:

  • Arthroscopic confirmation of tear via radiocarpal and DRUJ portals
  • Foveal debridement to bleeding bone (enhance healing)
  • Transosseous tunnel creation through ulnar fovea (outside-in or inside-out)
  • Suture passage through TFCC peripheral rim and foveal tunnel
  • Suture tied over bone bridge or ulnar cortex

• Suture Configuration:

  • Horizontal mattress sutures (most common)
  • Vertical mattress sutures
  • Simple sutures
  • Typically 2-3 sutures for secure fixation

• Outcomes:

  • Success rate: 80-90% good-excellent at 2-5 years
  • DRUJ stability restoration: 85-95%
  • Return to full activity: 75-80%

B. Arthroscopic Suture Anchor Repair [18]

• Technique:

  • Suture anchors placed in fovea under arthroscopic guidance
  • Sutures passed through TFCC and tied arthroscopically
  • Advantages: Technically easier, less risk of neurovascular injury
  • Disadvantages: Hardware cost, potential anchor failure

• Outcomes:

  • Similar success rates to transosseous technique (80-85%)
  • Recent meta-analysis showed no significant difference between techniques [18]

C. Open TFCC Repair

• Indications:

  • Large avulsion fragments
  • Failed arthroscopic repair
  • Combined injuries (e.g., ECU subluxation requiring sheath reconstruction)
  • Surgeon preference

• Technique:

  • Longitudinal incision over DRUJ (between 5th and 6th compartments)
  • Capsulotomy to expose TFCC
  • Direct visualization and repair using non-absorbable sutures
  • Suture anchors or transosseous tunnels

• Advantages: Direct visualization, larger tears manageable

• Disadvantages: More invasive, longer recovery, increased stiffness risk

Post-Operative Protocol:

• Immobilization (0-6 weeks):

  • Muenster splint (above-elbow, prevents rotation)
  • Maintain wrist in neutral, forearm in neutral
  • Critical: Protect repair during biological healing phase

• Passive ROM (6-8 weeks):

  • Remove splint
  • Begin gentle passive wrist and forearm ROM
  • No active pronation-supination

• Active ROM (8-10 weeks):

  • Progress to active ROM
  • Gentle strengthening

• Strengthening (10-12 weeks):

  • Progressive resistance exercises
  • Proprioceptive training

• Return to Sport (4-6 months):

  • Gradual sport-specific training
  • Protected return with taping/splinting as needed

Complications:

• Ulnar nerve injury (dorsal sensory branch): 5-10% (most common)
• Stiffness (loss of pronation-supination): 10-15%
• Re-tear: 10-15%
• DRUJ arthritis (long-term): 5-10%

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4. Ulnar Shortening Osteotomy (USO)

Indications:

• Ulnar impaction syndrome (Palmer 2B-2D) with ulnar-positive variance ≥2mm
• Failed conservative management
• Persistent ulnar-sided pain with MRI evidence of lunate chondromalacia or edema
• TFCC degenerative tear secondary to impaction

Contraindications:

• Neutral or negative ulnar variance (will not benefit from USO)
• Advanced ulnocarpal arthritis (Palmer 2E)—salvage procedure needed
• Active infection

Surgical Technique: [6,8,15]

• Approach: Longitudinal incision over ulnar shaft (distal third)
• Identify and protect:
  • Dorsal sensory branch of ulnar nerve
  • Ulnar artery (volar)
• Osteotomy:
  • Transverse or oblique cut in ulnar diaphysis (typically 3-5cm proximal to ulnar head)
  • Remove 2-4mm segment of bone (amount based on pre-op variance measurement)
  • Goal: Achieve neutral to slight negative variance (-1mm to 0mm)
• Fixation:
  • 6-hole 2.7mm or 3.5mm dynamic compression plate
  • Compression across osteotomy site
  • Screw fixation (typically 3 screws proximal and distal to osteotomy)

Biomechanical Effects:

• Unloads ulnocarpal compartment by 18% per 1mm of shortening
• Tightens TFCC and ulnocarpal ligaments (tension effect)
• May improve DRUJ congruity and stability
• Decompresses lunate and triquetrum

Post-Operative:

• Splint: 2 weeks (soft tissue healing)
• ROM: Begin gentle ROM at 2 weeks
• Radiographs: Serial X-rays at 2, 6, 12 weeks to assess union
• Protected use: Until radiographic union (typically 8-12 weeks)
• Plate removal: Often required due to subcutaneous position and symptomatic hardware (30-40% removal rate)

Outcomes:

• Good-excellent results: 70-85% [8,15]
• Pain relief: 75-80%
• Return to work: 3-6 months
• Return to sport: 4-6 months
• Union rate: 95%

Complications:

• Non-union: 5% (smoking, NSAIDs, inadequate fixation)
• Hardware irritation: 30-40% (often requires removal)
• Ulnar nerve injury: 5-10%
• Reflex sympathetic dystrophy (CRPS): 2-5%
• Loss of forearm rotation: 10-15% (typically less than 20° loss)

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5. Arthroscopic Wafer Procedure

Indications:

• Ulnar impaction syndrome with mild ulnar-positive variance (less than 2-3mm)
• Alternative to ulnar shortening osteotomy
• Patient preference for less invasive option

Technique:

• Arthroscopic debridement of central TFCC
• Arthroscopic resection of 2-3mm of distal ulnar dome (wafer resection)
• Performed through radiocarpal portals
• Creates functional ulnar shortening without osteotomy

Advantages:

• Less invasive than USO
• No hardware
• Faster recovery
• Lower complication rate

Disadvantages:

• Limited amount of shortening achievable (2-3mm maximum)
• Not suitable for ulnar variance > 3mm
• Does not tighten TFCC/ulnocarpal ligaments (no tension effect)

Outcomes:

• Recent meta-analysis: Wafer procedure vs USO showed similar pain relief and functional outcomes for ulnar variance less than 3mm [8]
• Good-excellent results: 70-80%
• Return to activity: 3-4 months (faster than USO)

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6. Salvage Procedures (Palmer 2E—Ulnocarpal Arthritis)

Indications:

• End-stage ulnocarpal arthritis
• Failed ulnar shortening or wafer procedures
• Severe DRUJ arthritis with intractable pain

A. Darrach Procedure

• Technique: Excision of distal 1-2cm of ulna
• Advantages: Simple, reliable pain relief
• Disadvantages: Ulnar instability, poor grip strength, cosmetic deformity (ulnar sag)
• Best for: Low-demand elderly patients, rheumatoid arthritis

B. Sauvé-Kapandji Procedure

• Technique:
  • Fusion of DRUJ (radius to ulna at joint level)
  • Creation of pseudarthrosis in ulnar shaft (2cm proximal to fusion)
• Advantages: Maintains ulnar support, better grip strength than Darrach
• Disadvantages: Risk of non-union at pseudarthrosis site, ulnar stump instability
• Best for: Younger, higher-demand patients

C. Ulnar Head Arthroplasty

• Technique: Replacement of ulnar head with prosthesis
• Indications: Isolated ulnar head arthritis, younger patients
• Outcomes: Promising early results, long-term data limited

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8. Complications and Adverse Outcomes

Surgical Complications

Nerve Injury:

• Dorsal Sensory Branch of Ulnar Nerve (DSBUN):
  • Most common complication (5-10% incidence)
  • Runs across arthroscopy portal sites (6R, 6U) and ulnar shortening incision
  • Manifestations: Numbness, painful neuroma, hyperesthesia
  • Prevention: Careful portal placement, skin incision technique, gentle soft tissue handling
  • Treatment: Neurolysis, neuroma excision, nerve burial in chronic cases

Stiffness:

• Loss of pronation-supination: 10-20% of repairs
• Typically less than 20° loss (acceptable in most patients)
• Risk factors: Prolonged immobilization, open repair, patient non-compliance with therapy
• Prevention: Early ROM (after 6 weeks protection), aggressive therapy

Re-tear:

• Incidence: 10-15% after arthroscopic repair
• Risk factors: Non-compliance with post-op protocol, return to high-risk activities too early, poor tissue quality
• Presentation: Recurrent ulnar-sided pain, clicking, instability
• Management: Revision repair vs salvage procedure

Hardware Complications:

• After USO: Plate irritation (30-40%), plate removal commonly required
• After suture anchor repair: Anchor pull-out (rare, 2-5%)

Non-Union (After USO):

• Incidence: 5%
• Risk factors: Smoking, NSAIDs, inadequate fixation, gap at osteotomy site
• Treatment: Revision ORIF with bone graft

Complex Regional Pain Syndrome (CRPS):

• Incidence: 2-5% (any wrist surgery)
• Prevention: Early ROM, adequate pain control, avoid overly tight dressings
• Treatment: Aggressive therapy, desensitization, sympathetic blocks, multidisciplinary pain management

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9. Prognosis and Return to Activity

Natural History (Untreated)

• Acute Stable Tears (1A): 50-60% improve with conservative management alone
• Acute Unstable Tears (1B): Progressive DRUJ instability and arthritis if untreated
• Degenerative Tears (Palmer 2): Progressive ulnar impaction sequence (2A → 2E) over 5-15 years in patients with positive variance

Surgical Outcomes Summary

Return to Activity Guidelines

Office Work:

• Light keyboard/computer: 2-4 weeks post-op
• Full duties: 6-8 weeks

Manual Labor:

• Light duty: 8-12 weeks
• Full duty: 3-6 months (depending on procedure)

Sports:

• Non-contact: 3-4 months
• Contact sports: 4-6 months
• High-demand (gymnastics, racquet sports): 6-9 months

Criteria for Return:

• Pain-free ROM (or near-baseline)
• Grip strength ≥80% of contralateral
• Negative provocative tests
• Radiographic healing (for USO)

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10. Evidence & Guidelines

Palmer Classification: The Foundation

The Palmer classification, published in 1989, remains the gold standard for TFCC injury categorization and treatment algorithms. Its enduring utility lies in the anatomical correlation with vascular zones and the direct surgical implications:

• Central tears (1A) = Avascular = Debride
• Peripheral tears (1B) = Vascular = Repair

This classification has been validated across multiple studies and remains the framework used in all contemporary TFCC literature. [1]

Foveal Repair: Biomechanical Superiority

Multiple biomechanical studies have confirmed that foveal (deep) attachment of the radioulnar ligaments provides superior DRUJ stability compared to styloid (superficial) attachment. This has led to the current emphasis on anatomic foveal repair for Palmer 1B injuries, with Atzei's subclassification guiding the specific repair technique. [13]

Ulnar Shortening vs Wafer: Recent Meta-Analysis

A 2024 systematic review and meta-analysis by Shi et al. compared arthroscopic wafer procedure to ulnar shortening osteotomy for ulnar impaction syndrome. Key findings:

• For ulnar variance less than 3 mm: No significant difference in outcomes between wafer and USO
• For ulnar variance ≥3 mm: USO superior outcomes
• Wafer procedure: Faster recovery, lower complication rate, no hardware issues
• USO: Greater biomechanical correction, tension effect on ligaments

This evidence supports a personalized approach based on degree of positive variance. [8]

Transosseous vs Suture Anchor Repair

A 2024 systematic review by Ma et al. comparing transosseous suture technique to suture anchor repair for foveal TFCC tears found:

• No statistically significant difference in DASH scores, VAS pain scores, or return to sport
• Both techniques showed 80-90% good-excellent outcomes
• Suture anchor technique: Shorter operative time, potentially lower learning curve
• Transosseous technique: Lower cost, no hardware concerns

These findings suggest technique selection should be based on surgeon experience and preference rather than evidence of superiority. [18]

Systematic Review of Palmer 1 Outcomes

McNamara et al. (2020) performed a systematic review of Palmer Type 1 TFCC injury outcomes:

• Overall satisfaction: 85% across all treatment modalities
• Repair of Palmer 1B: Best long-term outcomes (90% satisfaction)
• Debridement of Palmer 1A: 80% satisfaction
• Conservative management of stable tears: 60% satisfaction
• Key finding: Anatomic repair of unstable tears yields superior results to debridement or conservative care [19]

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11. Patient Education

What is the TFCC?

The Triangular Fibrocartilage Complex (TFCC) is a small but critical structure on the little-finger side of your wrist. Think of it as the "meniscus of the wrist"—a shock-absorbing cushion and stabilizer that allows smooth rotation of your forearm while protecting the small bones of your hand from excessive force.

It's made of fibrocartilage (tough, rubbery tissue) and ligaments that connect the two bones of your forearm (radius and ulna) and support the small bones of your wrist (carpals).

Why Did It Tear?

Traumatic Tears:

• Falling onto an outstretched hand with the wrist twisted
• Sudden twisting force (power tool kickback, pulling heavy object)
• Direct impact to the wrist

Degenerative Tears:

• Gradual wear and tear over time (common after age 50)
• Repetitive activities involving twisting or loading the wrist
• "Ulnar impaction"—when one forearm bone is slightly longer, it grinds into the wrist cushion over time

Symptoms You May Experience

• Deep, aching pain on the little-finger side of the wrist
• Sharp pain when turning doorknobs, using a screwdriver, or wringing towels
• Painful clicking or clunking with forearm rotation
• Weakness when pushing up from a chair or doing push-ups
• Wrist feels unstable or like it's "giving way"

Diagnosis: How We Confirm the Tear

• Physical Exam: Special tests to locate the pain and assess wrist stability
• X-rays: Check bone alignment and measure whether one forearm bone is longer (ulnar variance)
• MRI or MRI with contrast (MRA): Shows the tear and tells us if it's in a part that can heal
• Arthroscopy (if needed): Camera inside the wrist—the most accurate test and allows treatment at the same time

Treatment Options

Non-Surgical (For Stable Tears):

• Splinting: 4-6 weeks to allow healing
• Therapy: Strengthening exercises for wrist and forearm
• Injections: Cortisone injection to reduce inflammation (temporary relief)
• Success rate: 60-70% for stable tears

Surgical (For Unstable Tears or Failed Conservative Care):

• Arthroscopic Debridement (Trimming):

  • For tears in the avascular (non-healing) center zone
  • Remove frayed edges arthroscopically (minimally invasive)
  • Recovery: 3-4 months

• Arthroscopic Repair (Stitching):

  • For tears at the edge where blood supply exists (can heal)
  • Reattach torn ligament to bone with sutures
  • Requires 6 weeks in a splint to protect healing
  • Recovery: 4-6 months
  • Success rate: 80-90%

• Ulnar Shortening Surgery:

  • For "ulnar impaction"—when your ulna bone is too long and crushing the cushion
  • We remove a small segment (2-4mm) of bone and plate it
  • This "unloads" the cushion and allows it to heal
  • Recovery: 4-6 months
  • Success rate: 70-85%

The "Too Long" Bone Problem (Ulnar Impaction)

If your X-ray shows that your ulna bone is naturally a few millimeters longer than your radius bone (ulnar-positive variance), this creates excessive pressure on the TFCC every time you use your wrist. Over time, this grinds a hole in the cushion and damages the adjacent hand bones.

Imagine a door hinge where one pin is slightly too long—it causes uneven wear. Ulnar shortening surgery fixes this by cutting out a small piece of the ulna to make it the correct length, taking pressure off the cushion permanently.

What to Expect After Surgery

• Pain: Managed with medications, typically moderate for 1-2 weeks
• Splint/Cast: 2-6 weeks depending on procedure
• Physical Therapy: 8-12 weeks to regain strength and motion
• Return to Work:
  • Office work: 2-4 weeks
  • Manual labor: 3-6 months
• Return to Sports: 4-6 months
• Full Recovery: 6-12 months

Long-Term Outlook

• Most patients (80-90%) achieve good pain relief and return to normal activities after repair of unstable tears
• Degenerative tears have good outcomes (70-80%) if the underlying cause (ulnar impaction) is addressed
• Some stiffness (10-15° loss of rotation) is common but usually not functionally limiting
• Untreated unstable tears can lead to wrist arthritis over 10-20 years

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12. Examination Focus (Viva Vault)

Viva Question 1: Describe the blood supply of the TFCC and explain its surgical significance.

Model Answer:

The TFCC has a dual vascular pattern that fundamentally determines treatment strategy:

• Peripheral 10-20%: Vascularized zone supplied by branches of the ulnar artery (both dorsal and palmar branches) and terminal branches of the anterior interosseous artery. This peripheral rim has intrinsic healing capacity and is amenable to surgical repair. Tears in this zone can be reattached with sutures and will undergo biological healing if adequately protected.

• Central 80%: Avascular fibrocartilaginous zone that receives nutrition solely via synovial diffusion. This region has no intrinsic healing capacity. Tears in this central zone will not heal spontaneously or with repair, and thus require debridement (excision of unstable tissue).

Surgical Implication:

This vascular anatomy directly informs the Palmer classification treatment algorithm:

• Palmer 1B (peripheral/foveal tears): Repair—in the vascular zone, biological healing possible
• Palmer 1A (central perforations): Debride—in the avascular zone, no healing capacity

Understanding this vascular geography is critical to avoid futile repair attempts in the avascular zone and to identify repairable peripheral tears that, if treated appropriately, can restore DRUJ stability.

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Viva Question 2: What is the "Fovea Sign" and what is its clinical significance?

Model Answer:

The Fovea Sign is a highly specific clinical test for foveal disruption of the TFCC, which represents a Palmer 1B injury—the most important subtype from a stability standpoint.

Technique:

With the patient's forearm in neutral rotation, the examiner palpates with firm pressure in the "soft spot" located in the interval between the ulnar styloid process and the flexor carpi ulnaris (FCU) tendon, just distal to the ulnar head. This anatomical landmark corresponds to the foveal insertion site of the deep radioulnar ligaments.

Interpretation:

• Positive test: Deep, well-localized tenderness at this specific site
• Negative test: No tenderness or only superficial discomfort

Clinical Significance:

The Fovea Sign has been validated with 95% sensitivity and 87% specificity for foveal disruption of the TFCC. A positive fovea sign indicates disruption of the deep fibers (ligamentum subcruentum) that insert into the fovea—the primary stabilizers of the DRUJ. This finding, particularly when combined with positive DRUJ ballottement (instability), is a strong indication for arthroscopic or open TFCC repair rather than debridement.

In the clinical examination sequence, the Fovea Sign helps differentiate between central tears (Palmer 1A—typically tender over the DRUJ line dorsally but negative fovea sign) and peripheral foveal tears (Palmer 1B—positive fovea sign with instability), guiding the surgical decision-making process.

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Viva Question 3: Explain the concept of "ulnar variance," how it is measured, and its pathological significance.

Model Answer:

Definition:

Ulnar variance is the relative length difference between the distal articular surfaces of the radius and ulna, measured on the coronal plane. It represents a critical biomechanical parameter that determines load distribution across the wrist.

Measurement Technique:

Ulnar variance must be measured on a standardized posteroanterior (PA) radiograph with:

• Shoulder abducted 90°
• Elbow flexed 90°
• Forearm in neutral rotation (critical—pronation increases variance, supination decreases it)
• Wrist in neutral flexion-extension

The measurement is the perpendicular distance from the distal articular surface of the ulna to the distal articular surface of the radius at the level of the lunate fossa. Lines are drawn parallel to the long axis of the radius.

Classification:

• Neutral (0): Ulnar and radial articular surfaces are equal (±1mm is considered neutral)
• Positive (+): Ulna extends distal to radius by > 1mm
• Negative (-): Ulna is proximal to radius by > 1mm

Biomechanical Significance:

In normal neutral variance, the wrist transmits approximately 80% of axial load through the radiocarpal joint and 20% through the ulnocarpal joint (via TFCC). Each 1mm of positive ulnar variance increases ulnocarpal load transmission by approximately 18%. Thus, +2.5mm of positive variance results in 40% of axial load crossing the ulnocarpal joint—double the physiological amount.

Pathological Significance:

• Positive Variance: Creates ulnar impaction syndrome

  • Mechanism: Repetitive axial loading causes the ulnar head to impinge against the lunate and triquetrum
  • Cascade: TFCC degeneration → Chondromalacia → TFCC perforation → LT ligament tear → Ulnocarpal arthritis (Palmer 2A-2E sequence)
  • Treatment: Ulnar shortening osteotomy or arthroscopic wafer procedure to restore neutral variance

• Negative Variance: Decreases ulnocarpal load

  • May predispose to Kienbock's disease (lunate avascular necrosis) due to excessive radiocarpal loading
  • Can occur iatrogenically after radial shortening for distal radius fracture malunion

Dynamic Considerations:

Ulnar variance is not static—it changes with forearm rotation and grip:

• Pronation: Increases variance by 1-2mm (ulna translates distally)
• Supination: Decreases variance by 1-2mm (ulna retracts proximally)
• Grip: Increases variance by 0.5-1mm

This dynamic variance explains why some patients with borderline positive variance on standard radiographs develop impaction symptoms only with loaded, pronated activities (e.g., push-ups, gymnastics).

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13. References

1. Palmer AK. Triangular fibrocartilage complex lesions: a classification. J Hand Surg Am. 1989;14(4):594-606. DOI: 10.1016/0363-5023(89)90174-3

2. Minami A, Kato H, Iwasaki N. Triangular fibrocartilage complex tears. J Hand Surg Am. 2015;40(2):355-365. DOI: 10.1142/S0218810415010017

3. Mikic ZD. Age changes in the triangular fibrocartilage of the wrist joint. J Anat. 1978;126(Pt 2):367-384. PMID: 670297

4. Dmour A, Talal A, Alqahtani M, et al. Advancements in Diagnosis and Management of Distal Radioulnar Joint Instability: A Comprehensive Review Including a New Classification for DRUJ Injuries. J Pers Med. 2024;14(9):943. DOI: 10.3390/jpm14090943

5. Palmer AK, Glisson RR, Werner FW. Ulnar variance determination. J Hand Surg Am. 1982;7(4):376-379. DOI: 10.1016/s0363-5023(82)80148-4

6. Sammer DM, Rizzo M. Ulnar impaction. Hand Clin. 2010;26(4):549-557. DOI: 10.1016/j.hcl.2010.05.011

7. Jung HS, Park KH, Jeong JH, et al. Arthroscopic Transosseous Repair of Foveal Tears of the Triangular Fibrocartilage Complex: A Systematic Review of Clinical Outcomes. Arthroscopy. 2021;37(5):1614-1625. DOI: 10.1016/j.arthro.2020.12.209

8. Shi H, Wang X, Wang Y, et al. Arthroscopic wafer procedure versus ulnar shortening osteotomy for ulnar impaction syndrome: a systematic review and meta-analysis. J Orthop Surg Res. 2024;19(1):121. DOI: 10.1186/s13018-024-04611-4

9. Tay SC, Tomita K, Berger RA. The "ulnar fovea sign" for defining ulnar wrist pain: an analysis of sensitivity and specificity. J Hand Surg Am. 2007;32(4):438-444. DOI: 10.1016/j.jhsa.2007.01.022

10. Marcovici LL, Huang JI, Tyser AR. The TFCC table lift test: A clinical tool for detecting palmer 1B TFCC lesions. J Hand Surg Am. 2025;50(1):100348. DOI: 10.1016/j.jham.2025.100348

11. Haims AH, Schweitzer ME, Morrison WB, et al. Internal derangement of the wrist: indirect MR arthrography versus unenhanced MR imaging. Radiology. 2003;227(3):701-707. DOI: 10.1148/radiol.2273020398

12. Argintar E, Holzberg E, Berry M, et al. TFCC reattachment after traumatic DRUJ instability: a simple alternative to arthroscopic management. Bull Hosp Jt Dis (2013). 2010;68(2):95-99. PMID: 21107219

13. Atzei A, Rizzo A, Luchetti R, Fairplay T. Foveal TFCC tear classification and treatment. Hand Clin. 2011;27(3):263-272. DOI: 10.1016/j.hcl.2011.05.014

14. Chu-Kay Mak M, Ho PC. Arthroscopic-Assisted Triangular Fibrocartilage Complex Reconstruction. Hand Clin. 2017;33(4):625-637. DOI: 10.1016/j.hcl.2017.07.014

15. Constantine KJ, Tomaino MM, Herndon JH, Sotereanos DG. Comparison of ulnar shortening osteotomy and the wafer resection procedure as treatment for ulnar impaction syndrome. J Hand Surg Am. 2000;25(1):55-60. DOI: 10.1053/jhsu.2000.jhsu025a0055

16. Jawed A, Shekhar A, Kashyap A, Agarwal B. TFCC injuries: How we treat? J Clin Orthop Trauma. 2020;11(Suppl 4):S600-S605. DOI: 10.1016/j.jcot.2020.06.001

17. Park JH, Kim BS, Suh SW, et al. Arthroscopic one-tunnel transosseous foveal repair for triangular fibrocartilage complex (TFCC) peripheral tear. Arch Orthop Trauma Surg. 2018;138(1):117-125. DOI: 10.1007/s00402-017-2835-3

18. Ma HH, Hung SC, Wang ST, et al. Effectiveness of suture anchor and transosseous suture technique in arthroscopic foveal repair of the triangular fibrocartilage complex: a systematic review. J Orthop Surg Res. 2024;19(1):53. DOI: 10.1186/s13018-024-04530-4

19. McNamara CT, Vinson EN, Huang AJ, Wittstein JR. A Systematic Review and Analysis of Palmer Type I Triangular Fibrocartilage Complex Injuries: Outcomes of Treatment. Hand (N Y). 2020;15(5):583-593. DOI: 10.1055/s-0040-1713580

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