High-yield overview
Tendon Transfers | Grafts | Chronic Deficiency
3-6mWait for reconstruction
EIP→EPLClassic thumb transfer
Passive ROMEssential prerequisite
90-95%EIP transfer success
Extensor Zones (Kleinert-Verdan)
Zone I
PatternDIP joint level - mallet deformity pattern
Treatment
Zone II
PatternMiddle phalanx - central slip injuries
Treatment
Zone III
PatternPIP joint - boutonniere deformity risk
Treatment
Zone IV
PatternProximal phalanx - extensor mechanism
Treatment
Zone V
PatternMCP joint - sagittal band disruption
Treatment
Zone VI
PatternMetacarpal - subcutaneous location
Treatment
Zone VII
PatternWrist/retinaculum - EPL rupture site
Treatment
Zone VIII
PatternDistal forearm - muscle-tendon junction
Treatment
Critical Must-Knows
- Full passive ROM is mandatory before any reconstruction attempt.
- EIP to EPL transfer is the gold standard for isolated EPL rupture.
- Timing: 3-6 months post-injury for scar maturation before reconstruction.
- Palmaris longus is the first-choice donor for free tendon grafts.
- Pulvertaft weave (3-4 weaves) is the standard tendon attachment technique.
- Vaughan-Jackson syndrome: Sequential ulnar-to-radial extensor ruptures in rheumatoid arthritis.
Clinical Pearls
- "Always assess passive ROM before planning reconstruction
- "Two-stage reconstruction for severe scarring/adhesions
- "Rheumatoid cases require DRUJ synovectomy to prevent recurrence
- "Set tension with wrist neutral, MCP 45 degrees flexion
Clinical Imaging
Imaging Gallery
Critical Extensor Reconstruction Concepts
Passive ROM Prerequisite
Reconstruction fails if joints are stiff. Must achieve full passive ROM at all joints before attempting any extensor reconstruction. Release contractures first, reconstruct tendons second.
EIP to EPL Transfer
Gold standard for EPL rupture. EIP is expendable (EDC maintains index extension), has similar excursion to EPL, and provides 90-95% success rate for thumb extension restoration.
Tendon Graft Selection
Palmaris longus first choice. Present in 85%, provides 12-15cm length, minimal donor morbidity. Alternatives: plantaris (30cm), toe extensors, or ECRL slip.
Two-Stage Technique
For severe scarring. Stage 1: Silicone rod creates pseudosheath (3 months). Stage 2: Replace rod with tendon graft. Success rate 70-80% in difficult cases.
At a Glance
Extensor tendon reconstruction addresses chronic deficiency after failed primary repair or delayed presentation, with full passive ROM as an absolute prerequisite - stiff joints guarantee failure. EIP to EPL transfer is the gold standard for isolated EPL rupture (90-95% success rate), while palmaris longus is the first-choice free graft donor (present in 85%, 12-15cm length). Timing is 3-6 months post-injury for scar maturation. For severe scarring, two-stage reconstruction using a silicone rod to create a pseudosheath yields 70-80% success. In rheumatoid cases (Vaughan-Jackson syndrome), DRUJ synovectomy is mandatory to prevent recurrent ruptures.
Mnemonic
DIP-MID-PIP-PROX-MCP-META-WRIST-FOREARMExtensor Zones of the Hand
| D | DIP Zone I - DIP joint (mallet finger) |
| M | Middle Zone II - Middle phalanx |
| P | PIP Zone III - PIP joint (boutonniere) |
| P | Proximal Zone IV - Proximal phalanx |
| M | MCP Zone V - MCP joint |
| M | Metacarpal Zone VI - Metacarpal dorsum |
| W | Wrist Zone VII - Wrist/retinaculum |
| F | Forearm Zone VIII - Distal forearm |
| D | DIP Zone I - DIP joint (mallet finger) | P | Proximal Zone IV - Proximal phalanx | W | Wrist Zone VII - Wrist/retinaculum |
| M | Middle Zone II - Middle phalanx | M | MCP Zone V - MCP joint | F | Forearm Zone VIII - Distal forearm |
| P | PIP Zone III - PIP joint (boutonniere) | M | Metacarpal Zone VI - Metacarpal dorsum |
Hook:Start at the fingertip (DIP) and work proximally to remember extensor zones!
Mnemonic
EIP BESTTendon Transfer Donors
| E | EIP Extensor indicis proprius - for EPL reconstruction |
| I | Independent Independent wrist extensors (ECRB) to EDC |
| P | Peripheral Peripheral EDC slips for side-to-side |
| B | Brachioradialis BR to ECRB (for wrist extension) |
| E | EDM Extensor digiti minimi to small finger |
| S | Supernumerary Supernumerary extensors if present |
| T | Tendon grafts Palmaris, plantaris when transfers inadequate |
| E | EIP Extensor indicis proprius - for EPL reconstruction | B | Brachioradialis BR to ECRB (for wrist extension) | T | Tendon grafts Palmaris, plantaris when transfers inadequate |
| I | Independent Independent wrist extensors (ECRB) to EDC | E | EDM Extensor digiti minimi to small finger | ||
| P | Peripheral Peripheral EDC slips for side-to-side | S | Supernumerary Supernumerary extensors if present |
Hook:EIP BEST = the best expendable donors for extensor reconstruction!
Mnemonic
SMARTReconstruction Prerequisites
| S | Supple Supple joints with full passive ROM |
| M | Mature Mature scar tissue (3-6 months post-injury) |
| A | Adequate Adequate soft tissue coverage |
| R | Realistic Realistic patient expectations |
| T | Therapy Therapy commitment essential for success |
| S | Supple Supple joints with full passive ROM | R | Realistic Realistic patient expectations |
| M | Mature Mature scar tissue (3-6 months post-injury) | T | Therapy Therapy commitment essential for success |
| A | Adequate Adequate soft tissue coverage |
Hook:Be SMART before reconstruction - assess all prerequisites carefully!
Overview and Epidemiology
Definition
Extensor tendon reconstruction addresses chronic extensor deficiency through tendon transfers (rerouting expendable donors) or tendon grafts (bridging gaps with free tissue). Success depends on preserved passive joint mobility, appropriate donor selection, proper surgical technique, and intensive hand therapy.
Epidemiology
Chronic Extensor Deficiency:
- Failed primary repairs: 10-15% of acute extensor repairs develop chronic lag
- Delayed presentations: 20-30% of extensor injuries present beyond acute repair window
- Rheumatoid ruptures: Affect 10-15% of RA patients with wrist synovitis
- EPL ruptures post-Colles: 0.5-3% incidence, typically 4-12 weeks post-fracture
Demographics:
- Age distribution: Bimodal - young adults (traumatic), older adults (rheumatoid/atraumatic)
- Gender: Males greater than females for traumatic (3:1), females greater than males for rheumatoid (3:1)
- Occupation: Manual laborers, machinery operators at higher risk for trauma
Common Scenarios Requiring Reconstruction:
| Etiology | Typical Presentation | Preferred Technique |
|---|---|---|
| EPL rupture post-Colles | Loss of thumb IP extension 4-12 weeks post-fracture | EIP to EPL transfer |
| Rheumatoid sequential ruptures | Progressive loss of finger extension (ulnar to radial) | Side-to-side transfers, ECRB to EDC |
| Failed Zone V-VII repair | Chronic extensor lag after laceration repair | Free tendon graft or two-stage |
| Segmental tendon loss | Trauma with tissue loss | Free tendon graft (palmaris longus) |
| Post-burn contracture | Adherent extensors, MCP hyperextension | Tenolysis vs two-stage reconstruction |
Natural History Without Reconstruction
Functional Deficit Patterns:
- Thumb EPL loss: Inability to extend IP joint, weak pinch, difficulty with precision tasks
- Finger EDC loss: Extensor lag at MCP, compensatory hyperextension at IP joints
- Wrist extensor loss: Wrist drop, severe functional impairment
Adaptive Mechanisms:
- Adjacent tendon hypertrophy: Partial compensation from neighboring extensors
- Intrinsic muscle compensation: Limited MCP extension via intrinsics (inadequate)
- Functional adaptation: Activity modification, assistive devices
Pathophysiology and Surgical Anatomy
Passive ROM is Non-Negotiable
Cannot reconstruct active extension if passive range is limited. Stiff joints from arthritis, contracture, or adhesions must be addressed first through contracture release, joint mobilization, or arthrodesis. No tendon reconstruction will overcome fixed joint stiffness.
Extensor Anatomy
Thumb Extensors:
-
EPL (Extensor Pollicis Longus): Extends thumb IP and MCP joints, radial deviates wrist
- Origin: Ulna mid-shaft, interosseous membrane
- Course: Third dorsal compartment around Lister's tubercle
- Insertion: Distal phalanx base (dorsal)
- Excursion: 5-7cm
-
EPB (Extensor Pollicis Brevis): Extends thumb MCP joint
- First dorsal compartment with APL
- Insertion: Proximal phalanx base
-
APL (Abductor Pollicis Longus): Abducts and extends CMC joint
- First dorsal compartment
- Multiple insertions common
Finger Extensors:
-
EDC (Extensor Digitorum Communis): Common extensor to all four fingers
- Fourth dorsal compartment
- Interconnections via juncturae tendinum
- Independent MCP extension capability
-
EIP (Extensor Indicis Proprius): Independent index extensor
- Fifth dorsal compartment (with EDM)
- Lies ulnar to EDC index at MCP level
- Expendable donor - EDC provides adequate index extension
-
EDM (Extensor Digiti Minimi): Independent small finger extensor
- Fifth dorsal compartment
- Often duplicated
- Partially expendable
Extensor Hood Mechanism:
- Central slip inserts on middle phalanx base (PIP extension)
- Lateral bands join terminal tendon at DIP (DIP extension)
- Sagittal bands stabilize extensor at MCP (prevent subluxation)
- Intrinsics contribute via lateral bands
Expendable Donor Tendons
| Donor | Function Lost | Compensation | Limitations |
|---|---|---|---|
| EIP | Independent index extension | EDC extends index adequately | None - ideal donor |
| Palmaris longus | Weak wrist flexion | FCR/FCU maintain flexion | Absent in 15% |
| EDM | Independent small extension | EDC extends small finger | Weakens small finger extension |
| ECRL slip | Slight wrist extension loss | ECRB/ECU maintain extension | Limited length |
| Plantaris | Trivial plantar flexion loss | Gastrocnemius/soleus maintain function | Requires foot incision |
Pathophysiology of Extensor Failure
Traumatic Extensor Loss
Mechanisms:
- Laceration injuries: Clean division allowing primary repair
- Crush/avulsion: Segmental loss requiring grafting
- Degloving: Extensive soft tissue damage, compromised healing
- Closed rupture: Forceful flexion against resistance (Zone V-VII)
Failed Primary Repair:
- Gap formation: Inadequate repair strength, excessive tension
- Adhesion formation: Insufficient early mobilization, excessive scarring
- Re-rupture: Premature rehabilitation, weak repair construct
- Tendon necrosis: Vascular compromise, infection
Chronic Presentation:
- Retraction: Proximal tendon retracts to muscle-tendon junction
- Muscle contracture: Myostatic contracture after 3-6 months
- Distal stump fibrosis: Scar tissue replaces distal tendon
- Joint stiffness: Secondary contractures from prolonged immobility
This pathophysiology necessitates reconstruction rather than delayed primary repair.
Biomechanical Principles
Tendon Excursion Requirements:
- Finger extensors (EDC): 5-6cm excursion for full MCP-IP motion
- Thumb extensors (EPL): 5-7cm excursion for full MCP-IP motion
- Wrist extensors: 3-4cm excursion for wrist motion
Donor-Recipient Matching:
- Match excursion requirements (EIP and EPL both 5-7cm - perfect match)
- Match direction of pull (straight line reduces friction)
- Match muscle strength (adequate motor power)
Tension Setting Principles:
- Wrist position: Neutral (0 degrees flexion-extension)
- MCP position: 45 degrees flexion for fingers, extended for thumb
- Test intraoperatively: Passive wrist motion should produce reciprocal finger motion (tenodesis effect)
- Avoid over-tensioning: Causes swan-neck deformity, joint stiffness
- Avoid under-tensioning: Results in extensor lag
Classification Systems
Extensor reconstruction is organised by anatomical zone (Kleinert-Verdan, eight zones from DIP to forearm) and by reconstruction strategy. The success-rate ranges below are series-level estimates; the head-to-head Level I comparison of the two commonest strategies (EIP transfer vs free graft for EPL) found equivalent good/very-good outcomes of ~82% and ~88% respectively (According to PubMed, Keating et al, ANZ J Surg 2026, PMID 41797307).
Reconstruction Type Classification
| Type | Technique | Indications | Success Rate |
|---|---|---|---|
| Tendon Transfer | Reroute expendable donor to deficient extensor | Isolated loss, good vascularity, supple joints | 85-95% |
| Free Tendon Graft | Bridge gap with palmaris/plantaris | Segmental loss, clean wound | 75-85% |
| Side-to-Side Transfer | Connect adjacent EDC slips | Single EDC rupture with intact neighbors | 85-90% |
| Two-Stage Reconstruction | Stage 1: rod; Stage 2: graft | Severe scarring, adhesions, failed prior surgery | 70-80% |
Clinical Presentation
History
Chief Complaint:
- Inability to extend specific digit(s) or thumb
- Extensor lag: Incomplete extension despite effort
- Triggering/catching: Suggests adhesions rather than rupture
- Progressive weakness: Rheumatoid pattern
Timeline:
- Acute onset: Laceration, closed rupture (recent trauma)
- Subacute (weeks): Post-Colles EPL rupture (4-12 weeks)
- Progressive (months): Rheumatoid sequential ruptures
- Chronic (greater than 6 months): Failed repairs, late presentation
Functional Impact:
- Thumb EPL loss: Difficulty with precision pinch, turning keys, opening jars
- Finger EDC loss: Inability to release objects, weak grip, compensatory IP hyperextension
- Multiple digit involvement: Severe hand dysfunction, inability to work
Previous Interventions:
- Prior surgery: Number of procedures, types, outcomes
- Splinting history: Response to dynamic extension splints
- Therapy compliance: Intensive therapy required for success
Physical Examination
Inspection:
- Resting posture: Affected digit(s) in relative flexion
- Surgical scars: Indicate prior attempts, scar quality
- Skin quality: Thin, scarred skin suggests difficult reconstruction
- Muscle wasting: Thenar atrophy (EPL loss), forearm atrophy (long-standing)
Palpation:
- Tendon continuity: Palpate extensor mass during attempted extension
- Present: Thickened cord suggests intact but adherent tendon
- Absent: Gap or no palpable structure confirms rupture
- Distal DRUJ: Dorsal prominence, synovitis (rheumatoid)
- Muscle contraction: Palpable forearm muscle contraction despite no distal motion confirms rupture
Range of Motion:
Critical Assessment - PASSIVE ROM FIRST:
- PIPJ passive flexion-extension: Must be full (0-100 degrees)
- DIPJ passive flexion-extension: Must be full (0-80 degrees)
- MCP passive flexion-extension: Must be full (0-90 degrees)
- Thumb IP/MCP passive motion: Must be full
- Wrist passive motion: Should be functional (30-60 degrees flexion-extension)
If passive ROM limited - STOP. Address joint stiffness before any tendon work.
Active ROM:
- Isolated tendon testing:
- EPL: Extend thumb IP with hand flat on table (positive test = cannot lift thumb)
- EIP: Extend index finger with others flexed and held
- EDC: Extend each finger independently
- Extensor lag measurement: Degrees from full passive extension to active extension
- Compensatory patterns: IP hyperextension, intrinsic recruitment
Special Tests:
EPL Rupture Test:
- Hand flat on table, palm down
- Patient attempts to lift thumb off table
- Positive: Thumb remains flat (EPL ruptured)
- Negative: Thumb lifts easily (EPL intact)
Juncturae Tendinum Test:
- Immobilize middle, ring fingers in flexion
- Attempt index or small finger extension independently
- Limited extension: Dependent on juncturae (true independent extensor lost)
Intrinsic Tightness Test:
- Passively extend MCP joint, attempt PIP flexion
- Limited PIP flexion with MCP extended: Intrinsic tightness present
- Differentiate from extensor tightness (limits PIP flexion with MCP flexed)
Differential Diagnosis
The cardinal presentation is loss of active digital extension. The reconstruction plan changes completely depending on which of the following is responsible, so this differential must be worked through systematically before any tendon surgery is offered.
Differential Diagnosis of Lost Active Extension
| Diagnosis | Key Distinguishing Feature | Pattern of Loss | Implication for Reconstruction |
|---|---|---|---|
| Extensor tendon rupture (traumatic/attritional) | Forearm muscle contracts but no distal extension; gap on palpation; tenodesis effect lost | Specific tendon(s) - EPL after distal radius fracture, ulnar-to-radial in rheumatoid | Transfer or graft if passive ROM full |
| Posterior interosseous nerve (PIN) palsy | Affects ALL digit/thumb extensors plus EDM; radial wrist extension (ECRL) spared so wrist extends in radial deviation; no sensory loss | Multiple digits, no palpable gap, passive tenodesis intact | Treat the nerve first; tendon transfer (e.g. for radial nerve palsy) only if no recovery |
| Sagittal band rupture / extensor subluxation | Extensor slips ulnarly into the valley with MCP flexion; can hold extension if passively centralised; usually middle finger, radial band | Single MCP, dynamic | Sagittal band repair/reconstruction, not tendon transfer |
| MCP joint pathology (rheumatoid subluxation, arthritis) | Fixed volar subluxation, pain and crepitus, radiographic joint changes | MCP-level, often multiple | Address joint (synovectomy/arthroplasty); tendon rebalancing secondary |
| Adhesions / partial rupture | Passive ROM exceeds active ROM; triggering or thickened cord palpable | Tendon present but not gliding | Tenolysis rather than reconstruction |
| Fixed joint contracture | Passive extension itself limited (not just active) | Joint-level, fixed | Release/arthrodesis before any tendon work - reconstruction will fail |
According to PubMed, the sagittal band cause is well characterised: Hong et al found that direct sagittal-band repair restored full ROM and normalised DASH scores in chronic MCP extensor subluxation, confirming it is a distinct entity that should not be treated as a tendon rupture (J Hand Surg / Orthopade 2017, PMID 28721447).
Investigations
Imaging
Radiographs (AP, Lateral, Oblique):
Indications: All chronic extensor deficiency cases
Findings to assess:
- Bony prominences: Distal ulna (Vaughan-Jackson), Lister's tubercle (EPL rupture site)
- Malunion: Distal radius dorsal angulation causing tendon attrition
- Hardware: Prominent screws/plates causing mechanical attrition
- Arthritis: DRUJ, wrist, finger joints affecting reconstruction candidacy
- Fracture healing: Confirm union before reconstruction (Colles cases)
Ultrasound:
Indications:
- Confirm rupture vs adhesions
- Locate retracted tendon ends
- Assess tendon quality
Technique: High-frequency linear probe (greater than 10 MHz), dynamic assessment
Findings:
- Complete rupture: Tendon discontinuity, retracted stumps, gap
- Partial rupture: Thinned tendon, partial continuity
- Adhesions: Intact tendon with limited excursion
- Synovitis: Hypoechoic fluid around tendons (rheumatoid)
Advantages: Real-time, dynamic assessment, low cost, no radiation
MRI (T1, T2, STIR sequences):
Indications:
- Uncertain diagnosis
- Pre-operative planning for complex cases
- Assessment of muscle quality (atrophy, fatty infiltration)
- Evaluation of joint pathology
Findings:
- Tendon rupture: Signal discontinuity, tendon retraction, fluid in sheath
- Tendon quality: Thickened (chronic inflammation), thinned (attrition)
- Muscle atrophy: Reduced muscle bulk, T1 hyperintensity (fatty infiltration)
- Synovitis: T2/STIR hyperintensity around DRUJ, wrist
- Scar tissue: T1/T2 hypointensity in tendon bed
Limitations: Expensive, time-consuming, claustrophobia
Electrodiagnostic Studies (EMG/NCS):
Indications: Suspected nerve injury (PIN palsy) masquerading as tendon rupture
Findings:
- PIN palsy: Denervation in all finger/thumb extensors, wrist extensors (ECRB) spared
- Tendon rupture: Normal motor units, voluntary recruitment present
Useful to differentiate neurologic from tendon pathology.
Laboratory Studies
Rheumatoid Cases:
- Inflammatory markers: ESR, CRP (assess disease activity)
- Rheumatoid factor: Confirm RA diagnosis
- Anti-CCP antibodies: More specific for RA
Infection workup (if concerned):
- CBC: Leukocytosis suggests infection
- Blood cultures: If systemic signs
- Wound cultures: If draining sinus
Preoperative Assessment
Passive ROM Documentation:
- Critical: Measure and document passive ROM all joints
- Photography: Consider photos documenting passive motion
- Consent discussion: If passive ROM limited, discuss joint surgery first
Donor Availability:
- Palmaris longus test: Oppose thumb to small finger, flex wrist - look for central cord
- Present: 85% of population
- Absent: Consider plantaris or ECRL
- EIP presence: Should be present in all patients (very rare congenital absence)
Soft Tissue Assessment:
- Skin quality: Thin/scarred skin may require flap coverage
- Previous incisions: Plan incisions to avoid skin necrosis
- Infection history: Delay reconstruction if recent infection
Patient Factors:
- Occupation: Return to work expectations, timeline
- Hand dominance: Dominant hand may justify more aggressive reconstruction
- Therapy access: Access to certified hand therapist essential
- Compliance: Realistic assessment of ability to follow complex protocol
Management
Timing is Critical
Do NOT reconstruct before 3 months post-injury - scar tissue must mature. Do NOT delay beyond 6-12 months - muscle contracture and joint stiffness worsen outcomes. Optimal window: 3-6 months.
Non-Operative Management
Indications:
- Minimal functional deficit (patient acceptance)
- Severe medical comorbidities prohibiting surgery
- Inadequate passive ROM with refusal of joint surgery
- Very elderly/low-demand patients
Options:
Dynamic Extension Splinting:
- Relative indication: Recent rupture (less than 3 months), partial ruptures
- Mechanism: Outrigger provides passive extension force
- Duration: 6-12 weeks continuous wear
- Success: Low for complete ruptures (less than 20%), better for adhesions
Activity Modification:
- Adaptive equipment (built-up handles, key turners)
- Occupational therapy for compensatory strategies
- Acceptable for low-demand patients
Outcomes: Persistent functional deficit, progressive joint contracture, patient dissatisfaction common
Surgical Reconstruction
Patient Selection Criteria
Essential Prerequisites (SMART):
- Supple joints - Full passive ROM at all involved joints
- Mature scar - Minimum 3 months since injury/prior surgery
- Adequate soft tissue - Healthy skin coverage, no active infection
- Realistic expectations - Understanding of limitations, therapy commitment
- Therapy access - Access to certified hand therapist
Contraindications:
- Absolute: Active infection, inadequate passive ROM, unrealistic expectations
- Relative: Severe medical comorbidities, poor soft tissue, smoking (cessation 4 weeks pre-op)
Reconstruction Techniques
EIP to EPL Transfer Technique
Gold Standard for EPL Rupture
Indications:
- Chronic EPL rupture (post-Colles, rheumatoid, idiopathic)
- Failed EPL primary repair
- EPL loss from trauma
Advantages:
- EIP expendable (EDC provides adequate index extension)
- Similar excursion to EPL (5-7cm)
- Direct line of pull after rerouting
- Excellent success rate (90-95%)
Patient Positioning:
- Supine, arm on hand table
- Tourniquet on upper arm (250 mmHg)
- Hand pronated
Surgical Approach - Three Incisions:
Incision 1 - Dorsal Index MCP (2cm longitudinal):
- Identify EIP tendon (ulnar to EDC at MCP level)
- Typically both tendons visible to index - EIP is ulnar
- Tag EIP with marking suture
- Divide EIP as distally as possible (at extensor hood)
- Retrieve EIP proximally with traction
Incision 2 - Dorsal Wrist/Distal Forearm (4-5cm):
- Center over Lister's tubercle
- Extend 4cm proximally over EPL muscle belly
- Identify third dorsal compartment (EPL)
- Open compartment - find EPL distal stump (may be attenuated)
- Trace EPL muscle belly proximally - excise degenerated tendon
- Create subcutaneous tunnel from wrist incision to thumb (radial side)
Incision 3 - Thumb Dorsal IP Joint (1.5cm):
- Longitudinal over IP joint dorsum
- Identify EPL insertion on distal phalanx base
- Prepare EPL stump by freshening if adequate tissue
- If no distal stump: create bone tunnel in distal phalanx
Transfer Procedure:
- Retrieve EIP from index incision into wrist incision
- Pass EIP subcutaneously around radial wrist (mimic EPL course)
- Thread EIP through subcutaneous tunnel to thumb incision
- Weave EIP to EPL stump using Pulvertaft weave:
- Create 4-6mm longitudinal slit in EPL stump
- Pass EIP through slit
- Create second slit 5mm distal, pass EIP through again
- Repeat for 3-4 total weaves
- Suture each weave with 4-0 Ethibond/FiberWire
- Set tension: Wrist neutral, thumb MCP/IP joints extended (can passively flex to neutral)
- Intraoperative test: Passive wrist flexion extends thumb; wrist extension allows thumb flexion
- Trim excess EIP tendon
If no EPL distal stump available:
- Drill 2mm bone tunnel from dorsal to volar distal phalanx base
- Pass EIP through tunnel
- Suture to periosteum or button over volar pulp
Closure:
- Skin only (5-0 nylon or subcuticular)
- Avoid deep sutures (restrict glide)
Immobilization:
- Thumb spica splint
- Wrist 30 degrees extension
- Thumb CMC, MCP, IP extended
- Duration: 4 weeks
This technique provides excellent thumb extension restoration with minimal donor morbidity.
Addressing Underlying Pathology
Rheumatoid Cases - MUST ADDRESS DRUJ:
- DRUJ synovectomy: Remove inflammatory synovium
- Darrach procedure: Distal ulna excision (most common)
- Sauve-Kapandji: DRUJ fusion with proximal pseudarthrosis (preserves stability)
- Failure to address DRUJ: High re-rupture rate (up to 30%)
Post-Traumatic Cases:
- Remove prominent hardware: Screws, plates causing mechanical attrition
- Correct malunion: Osteotomy if severe dorsal angulation causing attrition
- Release scar/adhesions: Tenolysis of surrounding structures
Post-Burn Cases:
- Z-plasties: Lengthen contracted skin
- Skin grafts: Provide adequate soft tissue coverage
- Flap coverage: If deep structures exposed
Surgical Pearls and Pitfalls
Technical Pearls
Pulvertaft Weave Optimization:
- Three weaves minimum: Standard secure juncture
- Four weaves typical: Added strength at the cost of more bulk - optimise balance of security vs gliding resistance
- Suture technique: Horizontal mattress preferred over simple sutures (better purchase)
- Taper final end: Smooth transition reduces catching sensation
Tension Setting Mastery:
- Critical determinant of outcome: Over-tension (swan-neck), under-tension (lag)
- Standard position: Wrist neutral, MCP 45 degrees flexion
- Intraoperative test: Passive wrist flexion should extend fingers reciprocally
- Allowance for stretch: Set slightly tighter than desired (grafts stretch 10-15% over 3 months)
Donor Tendon Harvest:
- Palmaris identification: Resist thumb opposition against resistance - central cord most prominent
- Tendon stripper use: Requires experience - can transect tendon if improper technique
- Tag orientation: Mark proximal vs distal end (maintain correct orientation during weaving)
Incision Planning:
- Avoid perpendicular scars: Zigzag or S-incisions prevent contracture
- Respect previous scars: Incorporate when possible, maintain blood supply
- Minimize skin trauma: Careful handling prevents wound complications
Common Pitfalls and Avoidance
Attempting Reconstruction with Stiff Joints:
- Error: Proceeding despite limited passive ROM
- Consequence: Reconstruction fails, wasted surgery
- Avoidance: Mandatory passive ROM documentation pre-op; release contractures first
Inadequate Scar Maturation:
- Error: Reconstruction less than 3 months post-injury
- Consequence: Excessive adhesions, poor glide, re-rupture
- Avoidance: Wait 3-6 months unless soft tissues pristine
Improper Tension Setting:
- Over-tensioning:
- Consequence: Swan-neck deformity, joint stiffness, pain
- Avoidance: Set with MCP 45 degrees flexion, allow passive finger flexion intraoperatively
- Under-tensioning:
- Consequence: Persistent extensor lag, weak extension
- Avoidance: Set tension slightly tighter than desired (accounts for stretch)
Inadequate Weave Security:
- Error: Only 1-2 weaves, or inadequate suturing
- Consequence: Juncture failure, gap formation, rupture
- Avoidance: Minimum 3 weaves, horizontal mattress sutures each weave
Choosing Wrong Reconstruction Type:
- Error: Single-stage graft in severely scarred bed
- Consequence: Massive adhesions, non-functional result
- Avoidance: Two-stage for severe scarring; transfer over graft when possible
Neglecting Underlying Pathology (Rheumatoid):
- Error: Reconstructing tendons without addressing DRUJ synovitis
- Consequence: Re-rupture rate up to 30%
- Avoidance: ALWAYS perform DRUJ synovectomy + Darrach/S-K in rheumatoid cases
Excessive Bulk at Juncture:
- Error: Too many weaves, bunching of sutures
- Consequence: Adhesions, catching sensation, limited ROM
- Avoidance: Taper final end, trim excess, smooth juncture
Troubleshooting Intraoperative Issues
Cannot Pass Tendon Through Scarred Bed:
- Use infant feeding tube as guide
- Create new subcutaneous tunnel if old bed too scarred
- Consider two-stage approach
Insufficient Graft Length:
- Use plantaris (longer than palmaris)
- Use two palmaris grafts end-to-end
- Consider ECRL slip as augmentation
EIP Not Identifiable:
- Rare but possible (congenital absence)
- Use EDC slip to index finger as alternative
- Consider ECRB to EPL if no alternatives
Weak Distal Stump (Cannot Weave):
- Anchor graft directly to bone (drill tunnel)
- Use bone anchor or suture anchor
- Button technique over volar pulp
Postoperative Management and Rehabilitation
Extensor Reconstruction Rehabilitation Protocol
Weeks 0-4Immobilization Phase
Splint Type: Dorsal blocking splint or thumb spica (EPL cases)
Position:
- Wrist 30 degrees extension
- MCP 0 degrees extension (fingers) or thumb extended (EPL)
- IP joints free (allow gentle passive motion)
Activity:
- No active extension (protected healing)
- Passive IP/DIP flexion allowed (prevents stiffness)
- Edema control: Elevation, Coban wrapping
Purpose: Protect juncture healing (Pulvertaft weave or bone insertion).
Weeks 4-6Protected Active Motion Phase
Remove splint for exercises, reapply between sessions
Exercises:
- Place-and-hold: Passively extend digit, actively hold position (10 sec x 10 reps)
- Active extension: Gentle active extension within comfortable range
- Blocking exercises: Isolate MCP extension (hold PIP/DIP in slight flexion)
- Tendon gliding: Hook fist → straight fist → full extension sequence
Activity:
- Light ADLs (eating, grooming)
- NO gripping, NO lifting greater than 500g
Therapist supervision: Essential - prevent over-aggressive motion, monitor for complications.
Weeks 6-8Strengthening Phase
Discontinue splint (except nighttime if extensor lag present)
Exercises:
- Progressive strengthening: Putty (soft → medium → firm progression)
- Resistance bands: Gentle resistance to extension
- Grip strengthening: Begin gentle grip exercises
- Functional activities: Light work simulation
Activity:
- Return to light work (sedentary jobs)
- Avoid heavy lifting (still less than 5kg)
Monitor: Extensor lag (if increasing, decrease activity intensity).
Weeks 8-12Full Activity Phase
Unrestricted activity by 10-12 weeks
Goals:
- Full ROM restoration (0-90 degrees MCP, 0-100 degrees PIP)
- Strength 80-90% of contralateral
- No extensor lag (or less than 10 degrees acceptable)
Activity:
- Return to full work duties
- Return to sport (contact sports week 12)
- Heavy lifting permitted
Long-term: Continue strengthening if weakness persists; dynamic splinting if extensor lag greater than 20 degrees.
Protocol Modifications by Reconstruction Type
EIP to EPL Transfer:
- Thumb spica splint (wrist, thumb extended)
- Emphasize IP joint motion early (prevent stiffness)
- Begin pinch strengthening week 6
Free Tendon Graft:
- More conservative progression (graft weaker than transfer initially)
- Extend immobilization to 5 weeks if concerned about healing
- Slower strengthening progression
Two-Stage Reconstruction:
- Same as free graft protocol
- Higher vigilance for adhesions (aggressive therapy if motion plateaus)
- Consider early tenolysis (6 months) if severe adhesions
Side-to-Side Transfer:
- Can be slightly more aggressive (less tension on repair)
- Buddy tape affected and donor digits weeks 4-8
- Independent finger exercises less critical (coupled motion expected)
Monitoring for Complications
Extensor Lag:
- Acceptable: Less than 10 degrees (functional outcome)
- Concerning: 10-20 degrees (may improve with therapy)
- Unacceptable: Greater than 20 degrees (consider revision if persists beyond 3 months)
Adhesions:
- Clinical sign: Passive ROM greater than active ROM (discrepancy greater than 20 degrees)
- Management: Intensive hand therapy, dynamic splinting
- Surgical: Tenolysis at 6 months if failed conservative management
Swan-Neck Deformity:
- Cause: Over-tensioned reconstruction → MCP hyperextension, PIP flexion
- Prevention: Proper tension setting intraoperatively
- Management: PIP extension splinting; if severe, may need reconstruction release
Joint Stiffness:
- Prevention: Early passive IP motion during immobilization phase
- Management: Aggressive therapy, dynamic splinting, manipulation under anesthesia if refractory
Complications and Salvage
Complications of Extensor Tendon Reconstruction
| Complication | Incidence | Prevention | Management |
|---|---|---|---|
| Adhesions limiting glide | 15-25% | Early passive motion, minimize trauma | Intensive therapy, tenolysis at 6+ months |
| Rupture of transfer/graft | 5-10% | Adequate immobilization, proper tension | Revision reconstruction vs salvage |
| Persistent extensor lag | 10-20% | Proper tension setting, compliant therapy | Dynamic splinting, revision if greater than 30 degrees |
| Joint stiffness (IP/MCP) | 15-25% | Early passive IP motion | Aggressive therapy, manipulation, possible release |
| Swan-neck deformity | 5% | Avoid over-tensioning | PIP extension splinting, release if severe |
| Donor site morbidity | Less than 5% | Careful harvest technique | Usually resolves spontaneously |
| Infection | 2-3% | Sterile technique, prophylactic antibiotics | Antibiotics, possible debridement |
| Quadriga effect | Rare | Proper tension setting, avoid over-lengthening | Revision to adjust length |
Tendon Adhesions
Most common complication (15-25% incidence)
Clinical Presentation:
- Limited active extension with full passive extension
- Discrepancy between active and passive ROM (greater than 20 degrees)
- Palpable thickening/triggering along tendon course
- Plateau in ROM improvement despite therapy
Management:
-
Conservative (first-line):
- Intensive hand therapy (work-hardening protocol)
- Dynamic extension splinting (low-load prolonged stress)
- Tendon gliding exercises, massage, ultrasound therapy
- Duration: 3-6 months trial
-
Surgical Tenolysis:
- Timing: Minimum 6 months post-reconstruction (allow scar maturation)
- Technique: Release adhesions circumferentially around tendon, preserve juncture
- Post-op: Immediate active motion (regional anesthesia catheter for pain control)
- Outcomes: 60-75% improvement in ROM (some recurrent adhesion expected)
Outcomes and Evidence Base
Expected Outcomes by Reconstruction Type
| Reconstruction Type | Success Rate | Return to Function | Complication Rate |
|---|---|---|---|
| EIP to EPL transfer | 90-95% | 3-4 months | Less than 10% |
| Free tendon graft (single-stage) | 75-85% | 4-6 months | 15-20% |
| Two-stage reconstruction | 70-80% | 6-9 months | 20-30% |
| Side-to-side transfer | 85-90% | 3-4 months | 10-15% |
| Rheumatoid reconstructions | 60-80% | 4-6 months | 20-30% |
Prognostic Factors
Positive Prognostic Factors:
- Full passive ROM pre-operatively (most critical)
- Clean, well-vascularized soft tissues (traumatic greater than rheumatoid)
- Single tendon reconstruction (multiple tendons worse)
- Transfer over graft (vascularized tissue heals better)
- Patient compliance with therapy (essential)
- Non-smoker (smoking impairs tendon healing)
- Younger age (better healing potential)
Negative Prognostic Factors:
- Limited passive ROM pre-op (poor outcomes despite surgery)
- Multiple prior surgeries (scarring, adhesions)
- Rheumatoid arthritis (disease progression)
- Smoking (nicotine impairs healing)
- Diabetes (impaired healing)
- Poor compliance (inadequate therapy)
Level I (Systematic Review and Meta-Analysis)
Keating et al - EI Transfer vs Tendon Graft for EPL Reconstruction (Systematic Review & Meta-Analysis)
Key Findings:
- Pooled analysis of 9 studies comparing extensor indicis transfer versus free tendon graft for EPL ruptures not amenable to primary repair
- Good or very good Geldmacher scores in 81.8% after extensor indicis transfer
- Good or very good Geldmacher scores in 87.5% after free tendon grafting
- The two techniques gave a practically equivalent return to postoperative function
- Extensor indicis favoured as the more reliable option on theoretical and clinical grounds (no graft donor-bed dependence)
Clinical Implication: Both extensor indicis transfer and free graft restore thumb extension with comparable, good outcomes; extensor indicis transfer is the more reliable default for irreparable EPL rupture.
Source: ANZ J Surg. 2026;96(4):836-843
Level IV (Retrospective Case Series)
Adams et al - EIP to EPL Transfer After Distal Radius Fracture: Long-Term Outcomes
Key Findings:
- Seven patients followed long-term after extensor indicis proprius to EPL tendon transfer for fracture-related EPL rupture
- Isolated active index MCP extension preserved in 7/7 (100%) - confirms EIP is expendable
- 6/7 (86%) could extend index MCP and thumb IP against resistance
- Mean thumb IP extension lag only -5 degrees; mean index MCP extension 1 degree
- Mean QuickDASH 16, indicating good patient-reported function
Clinical Implication: EIP-to-EPL transfer gives durable thumb extension with preserved independent index extension and low residual disability.
Source: J Hand Ther. 2024;37(4):529-533
Level IV (Retrospective Case Series)
McIntyre, Stirling & McEachan - Outcomes of Surgical Treatment of Vaughan-Jackson Syndrome
Key Findings:
- Twelve cases of Vaughan-Jackson syndrome treated with distal ulna excision (Darrach) plus extensor tendon transfer
- Attritional extensor rupture from distal radioulnar joint arthritis/inflammation - underlying DRUJ pathology addressed in every case
- At mean 53 months: mean PRWHE 34.5, mean QuickDASH 28.2
- Ten of 12 patients satisfied; Net Promoter Score 42 despite residual functional deficit
- Only 2 patients required further surgery (total wrist arthrodesis)
Clinical Implication: In Vaughan-Jackson syndrome, combining tendon transfer with distal ulna excision gives high satisfaction and low reintervention, but a measurable functional deficit persists - counsel accordingly.
Source: J Wrist Surg. 2024;13(4):328-332
Level IV (Prospective Case Series)
Beris et al - Two-Stage Tendon Reconstruction with a Silicone Rod
Key Findings:
- Two-stage reconstruction in 20 patients (22 digits) with poor-prognosis (Boyes grade 2-5) injuries
- Stage 1 silicone (Hunter) rod creates a gliding pseudosheath; stage 2 passes the graft through that pseudosheath
- Good/excellent results in 82% (Buck-Gramcko) and 73% (modified Strickland) at mean 50-month follow-up
- Results compared favourably with classic Hunter two-stage free-graft reconstruction
- Low rates of post-reconstruction rupture and tenolysis
Clinical Implication: The silicone-rod two-stage strategy is the established salvage for severely scarred tendon beds where single-stage grafting would fail.
Source: J Hand Surg Am. 2003;28(4):652-660
Level V (Cadaveric Biomechanical Study)
Brown et al - Side-to-Side vs Pulvertaft Weave: Mechanical Strength
Key Findings:
- Cadaveric comparison of side-to-side cross-stitch repair versus a Pulvertaft (3-incision) weave
- Load at first failure, ultimate load and stiffness were all significantly higher for the side-to-side repair
- Pulvertaft repairs failed by suture knot slipping/pull-through then donor pulling through recipient
- Side-to-side repairs failed by intrasubstance fibre shearing of the donor tendon
- Stronger, stiffer junctures may permit earlier active mobilisation and fewer adhesions
Clinical Implication: Despite the Pulvertaft weave's traditional status, biomechanical data show side-to-side coaptation is at least as strong, supporting earlier active motion after transfer.
Source: J Hand Surg Am. 2010;35(4):540-545
Long-Term Outcomes
Function at 2 Years:
- EIP to EPL: 95% maintain functional thumb extension
- Free grafts: 80% maintain functional extension (some stretch/lag)
- Rheumatoid: 70% maintain function (disease progression affects outcome)
Patient Satisfaction:
- High (greater than 85%) for traumatic cases with successful reconstruction
- Moderate (60-70%) for rheumatoid cases (expectation management critical)
- Low (less than 50%) for failed reconstructions
Return to Work:
- Sedentary work: 3-4 months typical
- Manual labor: 4-6 months, may need job modification
- High demand athletes: 6-9 months, some permanent limitation
Evidence Base
Key Evidence for Extensor Tendon Reconstruction
Level V (Cadaveric Biomechanical Study)
Gillis, Athens & Rhee - Biomechanical Comparison of Tendon Coaptation Methods
Key Findings:
- 100 cadaveric tendons used to compare Pulvertaft weave versus single-pass side-to-side coaptation
- Side-to-side constructs had significantly higher peak load and stiffness than Pulvertaft weave constructs
- Coaptation bulk did not differ between Pulvertaft and side-to-side constructs
- Side-to-side coaptations showed higher peak gliding resistance through tissue planes
- Mesh versus braided suture made no difference to strength, bulk or gliding within a construct group
Clinical Implication: Side-to-side coaptation is biomechanically stronger and stiffer than the Pulvertaft weave; weave choice should weigh strength, gliding resistance and surgeon familiarity rather than assume Pulvertaft superiority.
Source: J Hand Surg Am. 2020;46(4):343.e1-343.e10
Level III (Systematic Review)
Kunes et al - Extensor Tendon Injury After Volar Locking Plating: Systematic Review
Key Findings:
- Ninety studies reviewed on extensor tendon injury after volar locking plate fixation of distal radius fractures
- Incidence of extensor tendon rupture ranged from 0% to 12.5%
- The extensor pollicis longus is the most commonly ruptured extensor tendon
- Dorsal screw prominence and dorsal fracture fragments are key, partly preventable risk factors
- Hardware removal plus tendon transfer or reconstruction may be required to restore extension
Clinical Implication: Iatrogenic extensor (especially EPL) rupture is a recognised and partly preventable complication of volar plating; intra-operative dorsal screw-length checks reduce risk.
Source: Hand (N Y). 2022;17(1_suppl):87S-94S
Level V (Case Report)
Kizilay & Turan - EIP Transfer for EPL Rupture with Distal Radius Fracture
Key Findings:
- Bilateral EPL ruptures occurring at the time of bilateral displaced distal radius fractures
- Both fractures fixed via volar Henry approach with bilateral volar plating
- Both EPL ruptures reconstructed with extensor indicis proprius tendon transfer
- Satisfactory thumb extension restored with no reported complications
- Demonstrates EPL rupture can occur acutely at injury, not only as the classic delayed (4-12 week) attritional rupture
Clinical Implication: Clinicians should examine thumb extension at presentation of displaced distal radius fractures; acute EPL rupture is reconstructible with EIP transfer alongside fracture fixation.
Source: Acta Orthop Traumatol Turc. 2023;57(1):46-49
Exam Viva Scenarios
Use these scenarios to practise clinical reasoning and management decisions
CLINICAL SCENARIOStandard
Scenario 1: EPL Rupture Post-Colles Fracture
CLINICAL PROMPT
"A 62-year-old woman presents 8 weeks after successful closed reduction and casting of a displaced distal radius fracture. She has sudden onset inability to extend her thumb IP joint that occurred 2 days ago without trauma. Fracture is healed on x-ray. Examination shows inability to actively extend thumb IP joint, but full passive motion. She can palpate EPL muscle contraction in forearm. What is your diagnosis and management?"
PRACTICAL APPROACH
For this classic case. This is a delayed EPL rupture following distal radius fracture - occurs in 0.5-3% of Colles fractures, typically 4-12 weeks post-injury. The mechanism is ischemic necrosis of EPL within the tight third dorsal compartment at Lister's tubercle from post-fracture swelling and ischemia. Clinically, the EPL rupture test is positive - she cannot lift her thumb off the table when hand is flat, confirming rupture. The palpable forearm muscle contraction without distal IP extension confirms the diagnosis. My management would be surgical reconstruction with EIP to EPL transfer, which is the gold standard. First, I would thoroughly assess passive ROM of her thumb IP and MCP joints - if she has full passive flexion and extension, she is an excellent candidate. The procedure involves three incisions: first, at the index MCP dorsally to harvest the EIP tendon, which lies ulnar to the EDC; second, at the dorsal wrist over Lister's tubercle extending proximally to identify the EPL muscle and ruptured tendon; and third, at the thumb IP joint dorsally. I would reroute the EIP around the radial wrist mimicking EPL's course, pass it to the thumb, and weave it to the EPL distal stump or bone insertion using a Pulvertaft weave with 3-4 passes. Critical is tension setting - I set it with the wrist in neutral and thumb MCP and IP extended, allowing passive thumb flexion to neutral. I test intraoperatively that passive wrist flexion produces thumb extension. Post-operatively, thumb spica splint for 4 weeks, then protected motion. Success rate is 90-95% with functional thumb extension restored by 3-4 months.
KEY CLINICAL POINTS
EPL rupture post-Colles: 0.5-3% incidence, delayed presentation 4-12 weeks
Mechanism: Ischemic necrosis in third compartment at Lister's tubercle
EIP to EPL transfer is gold standard (90-95% success)
Check passive ROM before surgery (mandatory prerequisite)
Pulvertaft weave for secure attachment, tension with wrist neutral
COMMON PITFALLS
Attempting primary repair of ruptured ends (too retracted, poor tissue)
Not checking passive ROM - reconstruction fails if joints stiff
Over-tensioning causing swan-neck deformity
Under-tensioning causing persistent extensor lag
FURTHER QUESTIONS
"What are alternatives if EIP is congenitally absent?"
"ECRB to EPL transfer - split ECRB, reroute to EPL. Success 85-90%."
"Describe the Pulvertaft weave technique."
"Create longitudinal slits in recipient tendon, pass donor through slits for 3-4 weaves, suture each weave. Large contact area gives a secure, low-bulk juncture."
"Why not use free tendon graft instead of transfer?"
"Transfer preferred - vascularized tissue, single-stage, higher success (90-95% vs 75-85%). Graft reserved if EIP/ECRB unavailable."
CLINICAL SCENARIOChallenging
Scenario 2: Rheumatoid Sequential Extensor Ruptures
CLINICAL PROMPT
"A 58-year-old woman with long-standing rheumatoid arthritis presents with progressive inability to extend her small and ring fingers at the MCP joints over the past 2 months. She has prominent distal ulna dorsally and synovial thickening at the wrist. Examination shows inability to actively extend small and ring finger MCPs, but passive extension is full. Middle finger extension is weak. What is your diagnosis and surgical management?"
PRACTICAL APPROACH
This is Vaughan-Jackson syndrome - sequential extensor tendon ruptures in rheumatoid arthritis from distal DRUJ synovitis and bony attrition. The typical pattern is ulnar-to-radial progression: EDM ruptures first (small finger), then EDC ring, then middle, then index. She currently has two confirmed ruptures (small, ring) with impending third (weak middle extension). I would examine her thoroughly, palpating over the MCP joints for tendon continuity - in ruptures, no palpable cord during attempted extension; in synovitis, thickened cord with weak extension. I would test each finger's independent MCP extension to map exactly which tendons are ruptured. My surgical management must address both the ruptured tendons AND the underlying DRUJ pathology. For reconstruction of two ruptures, I would perform: first, side-to-side transfer connecting EDM stump to intact EDC middle finger; second, EIP transfer from index to EDC ring finger to restore ring finger extension. Because the middle finger shows weakness suggesting impending rupture, I may need to augment with additional side-to-side or graft support. Critically, I must address the DRUJ pathology to prevent further ruptures - I would perform DRUJ synovectomy to remove inflammatory tissue, and likely a Darrach procedure (distal ulna excision) or Sauve-Kapandji to remove the bony prominence causing attrition. If I only reconstruct tendons without addressing the DRUJ, re-rupture rate approaches 30%. Post-operatively, dorsal blocking splint for 4 weeks, then protected motion. I would counsel her that outcomes are more guarded than traumatic cases (60-80% satisfactory) due to ongoing disease activity.
KEY CLINICAL POINTS
Vaughan-Jackson syndrome: sequential ulnar-to-radial extensor ruptures in RA
Typical sequence: EDM → ring → middle → index → EPL
MUST address underlying DRUJ pathology (synovectomy + Darrach/S-K)
Reconstruction: side-to-side for 1-2 ruptures, ECRB to EDC for 3+ ruptures
Outcomes guarded (60-80%) due to disease progression
COMMON PITFALLS
Reconstructing tendons without addressing DRUJ - high re-rupture rate
Missing impending ruptures (examine all fingers carefully)
Not counseling about guarded prognosis compared to traumatic cases
Not coordinating with rheumatology for disease control
FURTHER QUESTIONS
"What if all four EDC tendons are ruptured plus EPL?"
"Would use ECRB to all EDC tendons with free palmaris longus grafts, and EIP to EPL for thumb. Very complex reconstruction with guarded prognosis (60-70%)."
"What is the Mannerfelt lesion?"
"EPL rupture at volar wrist (within carpal tunnel) from attrition over scaphoid volar prominence in RA. Different from Vaughan-Jackson which is dorsal DRUJ."
"Describe Darrach vs Sauve-Kapandji procedures."
"Darrach: excise distal 1-2cm of ulna, preserves DRUJ motion, risk of instability. Sauve-Kapandji: fuse DRUJ, create proximal pseudarthrosis for forearm rotation, more stable."
CLINICAL SCENARIOChallenging
Scenario 3: Failed Extensor Repair with Severe Scarring
CLINICAL PROMPT
"A 35-year-old carpenter had EDC lacerations to index and middle fingers repaired primarily 8 months ago. Despite intensive hand therapy, he has 50 degrees extensor lag at both MCPs. The dorsum has thick, adherent scarring from multiple prior tenolysis procedures. Passive ROM at all joints is full (confirmed 0-90 degrees MCP, 0-100 degrees PIP). He is highly motivated to regain function. What is your management?"
PRACTICAL APPROACH
For this challenging case. This patient has failed primary extensor repair with significant extensor lag despite therapy and prior tenolysis attempts. The key favorable factor is full passive ROM at all joints - this confirms the joints are supple and he remains a candidate for reconstruction. The thick dorsal scarring and multiple prior surgeries indicate a severely compromised soft tissue bed that is hostile to tendon gliding. My management would be two-stage tendon reconstruction given the severe scarring. Attempting a single-stage free tendon graft would likely result in massive adhesions and failure in this scarred bed. Stage 1 involves inserting silicone Hunter rods (3-4mm diameter) from the distal EDC insertions or extensor hood proximally to either the intact EDC motor units or, if those are inadequate, to an alternative motor like ECRB. I would pass the rods through the scarred extensor bed, anchor them distally and proximally with non-absorbable sutures to prevent migration, and close the wounds. The purpose is to create a pseudosheath around the rod over the next 3 months - a gliding surface formed by the body's encapsulation response. During this time, he would perform gentle passive ROM to enhance pseudosheath formation. At Stage 2, performed 3 months later, I would harvest palmaris longus tendons bilaterally if needed, expose the rods proximally and distally, suture the grafts to the distal rod ends, pull the rods out proximally drawing the grafts through the pseudosheaths, and weave the grafts to the motor units using Pulvertaft weave technique with appropriate tension setting. Post-operatively, dorsal blocking splint for 4 weeks then protected motion. I would counsel that two-stage reconstruction has lower success than primary reconstruction (70-80% vs 90%) but is his best option given the scarred bed. If this fails, salvage options include MCP arthrodesis or acceptance of residual lag.
KEY CLINICAL POINTS
Full passive ROM = still a candidate for reconstruction despite failures
Severe scarring/multiple prior surgeries = indication for two-stage
Stage 1: Silicone rod creates pseudosheath over 3 months
Stage 2: Replace rod with tendon graft through pseudosheath
Success 70-80% (lower than primary but better than single-stage in scar)
COMMON PITFALLS
Attempting single-stage graft in severely scarred bed - will fail from adhesions
Proceeding if passive ROM was limited - address joints first
Not waiting adequate time between stages (minimum 3 months)
Not counseling about lower success compared to primary reconstruction
FURTHER QUESTIONS
"What if passive ROM was limited to 0-60 degrees MCP?"
"Would address joint stiffness first with MCP capsulotomy, volar plate release, or even arthrodesis before any tendon reconstruction. Cannot reconstruct active motion if passive motion absent."
"What are the graft donor options if bilateral palmaris longus absent?"
"Plantaris from foot (excellent length 25-30cm), toe extensors (EHL, EDL), or ECRL slip from forearm."
"What is the mechanism of pseudosheath formation?"
"Foreign body encapsulation response - body forms gliding layer (pseudosheath) around silicone rod. This provides low-friction surface for subsequent tendon graft."
MCQ Practice Points
Clinical Pearl
Q: What are the zones of extensor tendon injury in the hand and their significance?
A: Odd zones over joints, even zones between: Zone I (DIP) - mallet finger, Zone III (PIP) - boutonnière, Zone V (MCP) - fight bite location, Zone VII (wrist) - under retinaculum. Zone III injuries risk boutonnière deformity if central slip disrupted. Zone V requires thorough washout for human bite injuries.
Clinical Pearl
Q: What is the EIP to EPL transfer used for?
A: Extensor indicis proprius (EIP) transfer reconstructs extensor pollicis longus (EPL) rupture. Common indication: EPL rupture after distal radius fracture (Lister's tubercle attrition). EIP expendable as EDC provides index extension. Transfer rerouted subcutaneously to EPL insertion. Alternative: palmaris longus graft.
Clinical Pearl
Q: What tendon grafts are available for extensor tendon reconstruction?
A: Palmaris longus (absent in 15%): Ideal length, easy harvest. Plantaris: Longer, useful for multi-digit reconstruction. Toe extensors: EDL to lesser toes. Fascia lata: For larger defects. Graft length should be 10% longer than defect to allow tensioning. Two-stage reconstruction if significant scarring.
Clinical Pearl
Q: What is the mechanism and treatment of sagittal band injury?
A: Sagittal band rupture (usually radial side of middle finger) causes extensor tendon subluxation ulnarly with MCP flexion. Acute injuries: Splinting MCP in extension 4-6 weeks. Chronic injuries: Surgical repair or reconstruction using extensor slip, juncturae tendinum, or capsular flap. Often seen in rheumatoid arthritis.
Clinical Pearl
Q: What is a two-stage tendon reconstruction and when is it indicated?
A: Stage 1: Insert silicone rod to create pseudosheath in scarred bed, allow soft tissue equilibration (2-3 months). Stage 2: Replace rod with tendon graft through formed sheath. Indicated when severe scarring, absent sheath, or poor soft tissue bed precludes primary reconstruction. Maintains gliding channel.
Guidelines, Registries & Global Practice
Extensor reconstruction is a technique-driven field without large randomised trials or dedicated joint-registry data; the global standard rests on systematic reviews, case series and biomechanical work. The picture below summarises the worldwide evidence and where regional practice genuinely differs.
Global Epidemiology
| Measure | Figure | Source |
|---|---|---|
| EPL rupture after distal radius fracture (conservatively treated) | ~3.5% in one matched cohort ('hook'-shaped Lister tubercle a risk factor) | According to PubMed, Ogata et al, J Hand Surg Asian Pac Vol 2022 (PMID 36178420) |
| Extensor tendon rupture after volar locking plating | 0% to 12.5% across studies; EPL most commonly affected | According to PubMed, Kunes et al, Hand (N Y) 2022 (PMID 35168382) |
| Palmaris longus absence (graft availability) | ~25% bilateral absence in the overall series; unilateral absence commoner on the non-dominant hand | According to PubMed, Eric et al, Surg Radiol Anat 2010 (PMID 21107568) |
| Vaughan-Jackson syndrome | Attritional extensor rupture from DRUJ arthritis/inflammation; persistent functional deficit after surgery despite high satisfaction | According to PubMed, McIntyre et al, J Wrist Surg 2024 (PMID 39027023) |
Manual occupations (construction, agriculture, machinery) drive traumatic injury worldwide, while inflammatory arthropathy drives atraumatic and attritional rupture. Rheumatoid arthritis prevalence is broadly 0.5-1% globally, so rheumatoid extensor rupture is a comparable problem across health systems.
Guidance and Standard of Care, Side by Side
No society publishes a dedicated extensor-reconstruction guideline; recommendations are extrapolated from hand-surgery consensus and distal-radius-fracture guidance.
| Body / source | Relevant position | Evidence basis |
|---|---|---|
| AAOS (distal radius fracture CPG) | Recognises EPL rupture as a complication of both non-operative and operative treatment; supports surgical reconstruction (commonly EIP transfer) | Consensus / limited evidence |
| BOA / BSSH (UK) | Tendon transfer or graft for irreparable extensor loss with supple joints; certified hand-therapy access central to outcome | Expert consensus |
| Systematic review / meta-analysis | EIP transfer and free graft give equivalent functional return for EPL rupture (good/very good in ~82% vs ~88%) | Level I (PMID 41797307) |
| Biomechanical evidence | Side-to-side coaptation is at least as strong/stiff as the Pulvertaft weave, supporting earlier active motion | Level V cadaveric (PMID 20223604, 33279324) |
Points of genuine agreement: full passive ROM is a mandatory prerequisite; EIP-to-EPL transfer is the default for irreparable EPL rupture; severe scarring is managed in two stages; rheumatoid cases must address the DRUJ to prevent re-rupture.
Registry Evidence
There is no implant or joint registry for soft-tissue extensor reconstruction (no prosthesis is implanted), so registry-level survival data do not exist. The best comparative evidence is the Level I systematic review above plus pooled case series, not registry output - a key honesty point for the exam.
Global Practice Variation
- High- vs limited-resource settings: outcome depends heavily on access to a certified hand therapist; where structured therapy is unavailable, surgeons favour simpler, more robust constructs and may accept earlier arthrodesis for salvage.
- Graft vs transfer preference: equivalent outcomes mean choice is driven by local training and donor availability (palmaris longus absent in roughly a quarter of patients) rather than by superiority of one technique.
- Inflammatory disease: peri-operative immunosuppression is managed with the treating rheumatologist following the prevailing national perioperative guidance (e.g. ACR/EULAR-aligned recommendations), individualised to infection and flare risk; dedicated drug names and hold intervals vary by region and are deliberately not prescribed here.
This topic reflects Australian context with emphasis on early specialist hand surgery referral and multidisciplinary care.
EXTENSOR TENDON RECONSTRUCTION
Clinical summary
Extensor Zones (Kleinert-Verdan)
- •Zone I: DIP joint (mallet)
- •Zone II: Middle phalanx
- •Zone III: PIP joint (boutonniere)
- •Zone IV: Proximal phalanx
- •Zone V: MCP joint
- •Zone VI: Metacarpal
- •Zone VII: Wrist/retinaculum (EPL rupture site)
- •Zone VIII: Distal forearm
Reconstruction Prerequisites (SMART)
- •Supple joints - full passive ROM mandatory
- •Mature scar - wait 3-6 months post-injury
- •Adequate soft tissue coverage
- •Realistic patient expectations
- •Therapy access and commitment
Reconstruction Options
- •Tendon transfer: EIP to EPL (90-95% success)
- •Free graft: Palmaris longus (75-85%)
- •Side-to-side: Adjacent EDC (85-90%)
- •Two-stage: Rod then graft for scarring (70-80%)
EIP to EPL Transfer
- •Gold standard for EPL rupture
- •EIP expendable (EDC extends index)
- •Three incisions: index MCP, wrist, thumb IP
- •Reroute EIP around radial wrist to EPL
- •Pulvertaft weave 3-4 passes
- •Tension: wrist neutral, thumb extended
- •Splint 4 weeks, success 90-95%
Tendon Graft Donors
- •Palmaris longus: 1st choice (12-15cm, 85% present)
- •Plantaris: 2nd choice (25-30cm from foot)
- •Toe extensors: 3rd choice (8-12cm)
- •ECRL slip: Alternative (8-10cm)
Pulvertaft Weave
- •Gold standard tendon attachment
- •3 weaves = secure minimum
- •4 weaves = added strength, more bulk
- •Horizontal mattress sutures each weave
- •Taper final end (reduce bulk)
EPL Rupture Post-Colles
- •Incidence: 0.5-3% of distal radius fractures
- •Timing: 4-12 weeks post-fracture (delayed)
- •Mechanism: Ischemic necrosis at Lister's tubercle
- •Presentation: Cannot extend thumb IP, no trauma
- •Treatment: EIP to EPL transfer
- •Success: 90-95%
Vaughan-Jackson Syndrome
- •Sequential extensor ruptures in rheumatoid arthritis
- •Sequence: EDM → ring → middle → index → EPL
- •Mechanism: Attrition over distal ulna prominence
- •Reconstruction: Side-to-side, EIP/EDM transfers, ECRB to EDC
- •MUST do DRUJ synovectomy + Darrach/Sauve-Kapandji
- •Success: 60-80% (disease progression affects outcome)
Two-Stage Reconstruction
- •Indication: Severe scarring/adhesions
- •Stage 1: Silicone rod creates pseudosheath
- •Wait 3 months minimum (pseudosheath formation)
- •Stage 2: Replace rod with tendon graft
- •Success: 70-80% (vs 40% single-stage in scar)
Tension Setting
- •Most critical technical factor
- •Wrist neutral position
- •MCP 45 degrees flexion (fingers)
- •Thumb extended (EPL reconstruction)
- •Test: Passive wrist flexion → finger extension
- •Over-tension: Swan-neck deformity
- •Under-tension: Extensor lag
Rehabilitation Protocol
- •Weeks 0-4: Immobilization (splint)
- •Weeks 4-6: Protected active motion
- •Weeks 6-8: Strengthening
- •Weeks 8-12: Full activity
- •Early passive IP motion (prevent stiffness)
Complications
- •Adhesions: 15-25% (most common)
- •Rupture: 5-10% (revision vs salvage)
- •Extensor lag: 10-20% (revise if greater than 30 degrees)
- •Swan-neck: 5% (over-tensioning)
- •Joint stiffness: 15-25% (aggressive therapy)
Exam High-Yield Facts
- •Passive ROM is mandatory prerequisite
- •EIP to EPL for isolated EPL rupture
- •Palmaris longus first choice graft (85% present)
- •Two-stage for severe scarring
- •Rheumatoid: Address DRUJ pathology
- •Pulvertaft weave: 3-4 passes standard