**Always recite these first:** 1. Expendable donor 2. Adequate strength (M4+) 3. One tendon, one function 4. Straight line of pull 5. Synergistic if possible 6. Adequate amplitude 7. Soft tissue equilibrium 8. Passive ROM full **Low median = Lost opposition ONLY** - APB paralyzed - Thumb cannot oppose - Opponensplasty restores function **High median = Also lost:** - FPL (thumb IP flexion) - FDP index/middle - Pronator teres **Low ulnar = Intrinsic minus:** - Weak key pinch (adductor pollicis) - Clawing ring/small (lumbricals lost) - Weak grip (interossei lost) **High ulnar = Also lost:** - FDP ring/small fingers - Paradoxically LESS clawing ### Eight Fundamental Principles Every successful tendon transfer must satisfy these criteria: **The donor tendon must be functionally expendable.** - Loss of donor causes minimal deficit - Remaining tendons can compensate - Example: EIP expendable (EDC provides extension) Never sacrifice essential function to restore another. **Donor must have M4 or greater strength.** - M4 = movement against gravity and some resistance - Transferred muscle loses one grade of strength - M3 donor would become M2 (unacceptable) Check all donor muscles preoperatively. **Each transferred tendon performs ONE function.** - Do not split tendons to multiple insertions - Exception: Brand 4-tail (but single function: intrinsic) - Maintain mechanical advantage Trying to do too much = doing nothing well. **Transfer must have direct line of pull to insertion.** - Avoid sharp angles (friction, bowstringing) - Use pulleys if necessary - Preserve excursion Curved paths reduce efficiency and strength. **Ideal donors act synergistically with new function.** - Wrist extensors synergistic with finger flexors - Finger extensors synergistic with thumb opposition - Easier for patient to learn Not essential but significantly aids rehabilitation. **Donor excursion must match recipient requirements.** - FDS excursion: 7cm - EDC excursion: 5cm - Wrist motors: 3cm Insufficient amplitude = weak transfer. **No scarring, contracture, or active disease.** - Full passive ROM essential - No ongoing infection - Stable soft tissue coverage Correct contractures before transfer. **Transfer should cross only one joint when possible.** - Reduces tenodesis effect - Improves control - Exception: some intrinsic transfers Multi-joint transfers harder to control. **ALWAYS state these principles FIRST** when asked about any tendon transfer. Shows systematic thinking. Then apply to specific scenario. ### Patient Selection and Evaluation Wait **3-6 months** after nerve injury for spontaneous recovery. If no clinical or EMG improvement, proceed with transfer. Do NOT wait beyond 12 months - prolonged denervation causes irreversible muscle fibrosis. **History:** - Mechanism and timing of nerve injury - Previous surgery or repair attempts - Hand dominance and occupation - Patient goals and expectations - Compliance with rehabilitation **Examination:** - Full motor assessment (Medical Research Council grade) - Sensory examination (two-point discrimination) - Passive ROM of all joints - Joint stability (ligament integrity) - Soft tissue condition (scars, coverage) - Check all potential donor muscles (M4+ required) **Investigations:** - **EMG/NCS**: Confirm irreversible nerve damage - **Radiographs**: Rule out joint arthritis or contracture - **MRI**: Not routine, but useful if muscle quality uncertain ### General Operative Principles **Tensioning:** - Most critical and difficult aspect - Too tight: swan neck or boutonniere deformity - Too loose: inadequate function - Use intraoperative passive wrist motion to assess **Standard Tensioning Formulas:** - **Opponensplasty**: Thumb opposes base of small finger with wrist neutral - **FPL reconstruction**: IP joint flexed 20-30 degrees with wrist neutral - **Intrinsic reconstruction**: MCP flexion 70 degrees, IP extension full **Juncture Techniques:** - **Weave technique**: Strongest (Pulvertaft) - **End-to-end**: Use for tendon-to-tendon of similar size - **Side-to-side**: Use for static tenodesis - Minimum 3 weaves for Pulvertaft (some recommend 4-6) **Postoperative Protocol:** - **Week 0-3**: Immobilization in splint (position varies by transfer) - **Week 3-6**: Gentle active motion, protected - **Week 6-8**: Progressive strengthening - **Week 8-12**: Full activity as tolerated - **Final outcome**: 3-6 months **3-6 weaves minimum.** Use non-absorbable suture (e.g., 3-0 Ethibond). Pass donor tendon through recipient multiple times. Most secure juncture technique. Withstands greater than 250N force biomechanically. ### Tendon Transfer Biomechanical Principles **Strength Loss After Transfer:** - Transferred muscle loses ONE grade of strength - M5 donor becomes M4 after transfer - M4 donor becomes M3 (acceptable functional level) - M3 donor becomes M2 (unacceptable - insufficient) **Excursion Requirements:** - **Opponensplasty**: 3-5cm excursion needed - **FPL reconstruction**: 5cm excursion - **Intrinsic transfers**: 2-3cm excursion - **Wrist motors**: 3cm excursion (insufficient for finger work) **Donor Excursion Available:** - FDS: 7cm (excellent for most transfers) - EDC/EIP: 5cm (good for opposition, intrinsics) - ECRL/ECRB: 3cm (limited use without graft) - Wrist flexors: 3cm (need graft for finger work) **Moment Arm Considerations:** - Preserve or improve moment arm at insertion - Pulley systems maintain moment arm - Direct insertion may need bone tunnel placement **Work Capacity:** - Work = Force × Distance - Transferred tendon must perform equivalent work - Cannot expect full strength restoration - Realistic goal: M3-M4 functional strength Tendon transfer CANNOT restore normal strength. Set realistic patient expectations: goal is functional independence (M3-M4), not athletic performance (M5). Inform patients preoperatively. ### Postoperative Therapy Protocol Successful tendon transfer requires **excellent patient compliance** with therapy. **Phase 1: Protection (Weeks 0-3)** - Splint in position specific to transfer - NO active motion - Edema control, finger ROM of uninvolved digits - Patient education **Phase 2: Early Active Motion (Weeks 3-6)** - Remove splint for therapy sessions - Gentle active motion of transferred tendon - Re-education: patient learns new motor pattern - Splint between sessions **Phase 3: Strengthening (Weeks 6-12)** - Progressive resistance exercises - Functional activities - Discontinue splint (gradual weaning) - Return to work planning **Phase 4: Maturation (Months 3-6)** - Continued strengthening - Refinement of motor control - Final outcome assessment Starting active motion too early (before 3 weeks) risks rupture at juncture site. Starting too late (after 6 weeks) risks adhesions and stiffness. **3 weeks is the sweet spot** for most transfers. ### Brand EIP Transfer - Gold Standard Technique **Indications:** - Irreversible low median palsy with loss of opposition - Failed nerve repair (6+ months, no recovery) - Patient motivated for rehabilitation - Full passive thumb ROM **Contraindications:** - Inadequate passive ROM (correct first) - Active infection or poor soft tissue coverage - Patient non-compliance anticipated - Ongoing nerve recovery (wait) **Patient Position:** - Supine, arm on hand table - Shoulder abducted 90 degrees - Tourniquet on upper arm **Surgical Steps:** ### Step 1: Harvest EIP Tendon **Incision:** - Longitudinal incision over dorsal 2nd metacarpal (6-8cm) - Centered over index MCP joint - Extend proximally to mid-metacarpal **Dissection:** - Incise skin and subcutaneous tissue - Protect dorsal sensory nerves (radial nerve branches) - Identify extensor tendons over index finger **EIP Identification:** - EIP lies ULNAR to EDC-index - Both insert on index proximal phalanx - Test: independent index extension with MP joints flexed **Harvest:** - Divide EIP at insertion on proximal phalanx - Confirm EDC-index still provides full extension - Free EIP proximally with blunt dissection **EIP is ULNAR to EDC-index.** Test: flex all MCP joints - EIP can extend index independently, EDC cannot. CONFIRM before dividing! Cutting EDC causes permanent index extension deficit. **PIN lies deep to supinator in proximal forearm.** When freeing EIP proximally, stay superficial to avoid PIN injury. Injury causes loss of thumb/finger extension - devastating complication. ### Step 2: Route EIP Around Radial Wrist **Wrist Incision:** - Transverse incision at wrist dorsum (3-4cm) - Centered over Lister's tubercle - Extend radially toward radial styloid **Create Subcutaneous Tunnel:** - Retrieve EIP proximally through wrist incision - Create wide subcutaneous tunnel around radial wrist - Avoid superficial radial nerve branches - Pass from dorsal to volar **Volar Routing:** - EIP passes between FCR and radial artery - PROTECT radial artery (lateral to FCR) - Use blunt dissection, visualize artery - Route EIP superficial to artery **Radial artery lies between FCR and brachioradialis.** Laceration causes massive bleeding. Visualize and protect artery before passing EIP volar. Primary repair essential if injured. ### Step 3: Insert into APB Insertion **Thumb Incision:** - Volar-radial incision over thumb MCP joint (2-3cm) - Along thenar crease - Protect radial digital nerve **Identify APB Insertion:** - APB inserts on radial base proximal phalanx - Also into extensor hood (variably) - May be atrophied - identify remnant **Pass EIP:** - Create subcutaneous tunnel from wrist to thumb - Pass EIP to thumb MCP area - Ensure no twisting or kinking **Weave Technique:** - Pulvertaft weave into APB remnant OR - Bone tunnel in proximal phalanx if APB absent - 3-4 passes minimum - Use 3-0 non-absorbable suture (Ethibond, Fiberwire) ### Step 4: Tensioning - CRITICAL STEP **Proper Tension:** - Thumb should oppose to **BASE** of small finger - NOT to tip of small finger (too tight) - Wrist in neutral position - Thumb MCP slightly flexed (30-40 degrees) **Assess:** - Thumb should reach small finger base comfortably - Should be able to adduct thumb back to palm - No excessive force required **"Base not tip!"** Tension Brand transfer so thumb opposes BASE of small finger, wrist neutral. Tensioning to tip makes transfer too tight - thumb cannot adduct back to palm. Common error! **Complete Weave:** - Secure weave with multiple interrupted sutures - Test tension by passive wrist motion - Trim excess EIP tendon ### Step 5: Closure and Splinting **Wound Closure:** - Close all incisions with absorbable subcuticular sutures - Steri-strips, sterile dressing - Soft dressing **Splint:** - Thumb spica splint - Thumb in full opposition (to small finger) - Wrist neutral - Forearm included for stability **Postoperative Care:** - Elevate for 48 hours - Keep splint dry and intact - Immobilize 3 weeks strict - Remove sutures 2 weeks ### Step 6: Rehabilitation Protocol **Weeks 0-3:** - Immobilization in thumb spica - No active motion - Edema control **Weeks 3-6:** - Remove splint for therapy - Begin active opposition exercises - Re-education (learn to activate EIP for opposition) - Splint between sessions **Weeks 6-12:** - Progressive strengthening - Functional activities - Wean splint - Return to light work **Months 3-6:** - Full strengthening - Return to full duty work - Final outcome assessment **Expected Outcome:** - 85-95% achieve functional opposition - Pulp-to-pulp pinch restored - Strength 60-80% of normal side - High patient satisfaction **Most common in weeks 3-6.** Presents as sudden loss of opposition. Requires reoperation and re-weaving. Prevention: strict 3-week immobilization, minimum 3-4 Pulvertaft passes, gradual mobilization. ### Royle-Thompson FDS Transfer **Donor:** FDS ring finger **Advantages:** - Strong donor (M5 typically) - Good excursion (7cm) - Excellent outcomes **Disadvantages:** - Loses ring finger independent PIP flexion - More complex harvest than EIP **Technique:** - Harvest FDS-ring through volar approach - Route subcutaneously around ulnar wrist - Insert into APB or bone tunnel - Tension same as Brand (base of small finger) ### Phalen-Miller APL Transfer **Donor:** Abductor pollicis longus **Advantages:** - Local donor (thumb area) - Simple surgery - No distant harvest **Disadvantages:** - Short amplitude (may need tendon graft) - Removes thumb abduction power - Less reliable outcomes **Technique:** - Expose APL at radial wrist - Divide at insertion on 1st metacarpal base - May need palmaris longus graft for length - Route to APB insertion - Tension as per Brand ### Camitz Palmaris Longus Transfer **Donor:** Palmaris longus with volar fascia extension **Advantages:** - Simple, low morbidity - Can be done during carpal tunnel release - Good for elderly, low demand **Disadvantages:** - Weak motor (PL is weak tendon) - Not durable for young patients - 25% of patients lack palmaris longus **Technique:** - Harvest PL with strip of palmar fascia for length - Route subcutaneously to thumb - Insert into APB - Only for low-demand patients ### Reconstruction for High Median Nerve Lesions **High median palsy** affects nerve proximal to forearm. Additional deficits beyond opposition: **In addition to opposition:** - **FPL**: Thumb IP flexion lost - **FDP index/middle**: DIP flexion lost - **Pronator teres**: Weak pronation - **FDS all fingers**: May be lost if very proximal Multiple transfers required. **Staged reconstruction:** 1. **Opposition**: EIP opponensplasty (as above) 2. **FPL function**: Brachioradialis to FPL 3. **Index/middle FDP**: Side-to-side to ring/small FDP 4. **Pronation**: Usually adequate from gravity/other muscles Prioritize most important functions. ### Brachioradialis-to-FPL Transfer **Indications:** High median palsy with lost thumb IP flexion **Technique:** - Expose brachioradialis in distal forearm - Divide at insertion (radial styloid) - Route deep in forearm to FPL - Pulvertaft weave into FPL - Tension: Thumb IP flexed 20-30 degrees, wrist neutral - Immobilize 3 weeks **Outcomes:** Good restoration of thumb IP flexion, key pinch strength ### FDP Index/Middle Reconstruction **Options:** 1. **Side-to-side to ring/small FDP**: Simple, allows mass flexion 2. **ECRL-to-FDP**: Independent flexion maintained 3. **Accept deficit**: If patient has mild symptoms only Most patients do well with side-to-side tenodesis to ulnar-innervated FDP tendons. ### Median Palsy Transfer Complications **Intraoperative:** - **Radial artery injury**: Primary repair essential - **Superficial radial nerve injury**: Painful neuroma, bury or repair - **EDC division instead of EIP**: Repair EDC, abort or revise plan - **PIN injury**: Devastating - prevent with careful dissection **Early Postoperative (0-6 weeks):** - **Juncture rupture** (2-5%): Sudden loss of opposition, needs reoperation - **Infection** (less than 1%): Antibiotics, possible washout - **Hematoma**: Drain if symptomatic **Late Complications (6+ weeks):** - **Inadequate opposition**: Under-tensioning - may need revision - **Swan neck deformity**: Over-tensioning - release transfer - **Adhesions**: Tenolysis may be needed - **Persistent thenar atrophy**: Cosmetic concern only if function good ### Zancolli FDP Lasso Procedure - Simplest Claw Correction **Indications:** - Low ulnar palsy with claw deformity - MCP hyperextension, PIP/DIP flexion (ring/small fingers) - Low-demand or elderly patients - Failed conservative management (splinting) **Contraindications:** - Fixed MCP contracture (release first) - High ulnar palsy (FDP also paralyzed) - High-demand patients wanting physiologic reconstruction **Principle:** - Use FDP itself as donor (no separate donor needed) - Create lasso around A1 pulley - FDP pull flexes MCP joint (corrects hyperextension) - Passive IP extension follows (intrinsic cascade) **Patient Position:** - Supine, arm on hand table - Tourniquet on upper arm **Surgical Steps:** ### Step 1: Incision and Exposure **Incisions:** - Bruner zigzag incisions over A1 pulleys - Ring and small fingers (can do middle if also involved) - Center over proximal digital crease **Dissection:** - Incise skin carefully (avoid neurovascular bundles) - Identify A1 pulley (transverse fibers at MCP level) - Identify FDP tendon (deeper than FDS) **Ulnar digital nerve to small finger** lies along ulnar border. Use Bruner/zigzag incisions to avoid direct cut over nerve. Retract radially during surgery. ### Step 2: Create FDP Lasso **Split FDP Longitudinally:** - Split FDP into two equal slips - Split length: 2-3cm proximal to A1 pulley - Use sharp knife or scissors **Create Lasso Around A1:** - Pass one FDP slip volar to A1 pulley - Pass other FDP slip dorsal to A1 pulley - Creates "lasso" configuration around A1 - A1 acts as pulley for FDP **Preserve A2/A4 Pulleys:** - DO NOT release A2 or A4 pulleys - Only A1 is used for lasso - A2/A4 prevent bowstringing ### Step 3: Tensioning - CRITICAL **Proper Tension:** - MCP flexion 70 degrees with wrist neutral - IP joints should extend fully passively - NO forced flexion or extension **Test Tension:** - Passively extend wrist - MCP should flex more - Passively flex wrist - MCP should extend slightly - Tenodesis effect confirms proper tension **Suture FDP Slips:** - Suture two FDP slips to each other - Use 3-0 non-absorbable suture - Multiple interrupted sutures - Secure knots **MCP 70 degrees, NOT 90 degrees.** Over-tensioning to 90 degrees causes MCP flexion contracture and swan neck deformity. 70 degrees is the magic number! ### Step 4: Closure and Splinting **Closure:** - Close skin with absorbable sutures - Steri-strips, sterile dressing **Splint:** - Hand-based splint - MCP flexed 70 degrees - IP joints extended - Wrist neutral - Immobilize 3 weeks ### Step 5: Rehabilitation **Weeks 0-3:** - Immobilization strict - Edema control - Uninvolved finger ROM **Weeks 3-6:** - Remove splint for therapy - Active MCP flexion exercises - Passive IP extension - Splint between sessions **Weeks 6-12:** - Progressive strengthening - Functional grip activities - Wean splint - Return to work **Expected Outcomes:** - Corrects MCP hyperextension in 85-90% - Some loss of DIP flexion (10-20 degrees) - Patient satisfaction high - Simple, low morbidity Zancolli lasso **reduces DIP flexion by 10-20 degrees** because FDP force redirected to flex MCP. Acceptable tradeoff for most patients. Inform preoperatively. ### Brand Four-Tail FDS Transfer - Most Physiologic **Indications:** - Low ulnar palsy with claw deformity - Young, high-demand patients - Desire for physiologic intrinsic reconstruction - Inadequate results from Zancolli lasso **Advantages Over Zancolli:** - Active motor (FDS donor) - Restores both MCP flexion AND IP extension - No DIP flexion loss - More physiologic function **Disadvantages:** - More complex surgery - Longer operative time - Requires FDS sacrifice (loses independent PIP flexion one finger) **Donor Selection:** - Usually FDS middle or ring finger - Choose based on patient preference - Requires M4+ strength **Surgical Steps:** ### Step 1: Harvest FDS Donor **Incision:** - Volar zigzag incision over donor finger (middle or ring) - Expose FDS tendon in palm and digit **Harvest:** - Divide FDS at insertion (middle phalanx) - Free FDS from vincula - Retrieve proximally into palm - Confirm FDP still functional ### Step 2: Split FDS Into Four Tails **Split Technique:** - Split FDS longitudinally into 4 equal slips - Each tail for one lateral band (index, middle, ring, small) - Equal thickness important ### Step 3: Route Through Lumbrical Canals **Route Each Tail:** - Pass each FDS tail through lumbrical canal - Radial side of each finger - Volar to transverse metacarpal ligament - To lateral band of each finger ### Step 4: Insert Into Lateral Bands **Weave Technique:** - Pulvertaft weave each tail into lateral band - At proximal phalanx level - 2-3 passes per tail - Use 4-0 non-absorbable suture **Tensioning:** - MCP flexed 70 degrees - IP extended fully - Equal tension all four tails - Test by passive wrist motion ### Step 5: Rehabilitation Same as Zancolli - 3 weeks immobilization, then gradual mobilization. **Outcomes:** - 85-90% claw correction - Better MCP flexion than Zancolli (15 degrees more) - Active IP extension - No DIP flexion loss - High satisfaction in young patients ### Restoring Key Pinch - Eliminate Froment's Sign **Froment's sign** indicates weak key pinch from adductor pollicis paralysis. Thumb IP flexes when attempting lateral pinch (FPL compensates). **Clinical Impact:** - Cannot perform strong key pinch - Writing difficult - Tool use impaired - Patient frustration high **Reconstruction Priority:** - Often MORE important than claw correction - Restores key pinch strength 50-80% - High patient satisfaction - Essential for hand function ### EIP-to-Adductor Pollicis Transfer **Most Common Technique:** **Donor:** Extensor indicis proprius **Surgical Steps:** **Step 1: First Web Space Release** - **ESSENTIAL FIRST STEP** - Chronic ulnar palsy has adduction contracture - Release contracted first dorsal interosseous - Release adductor fascia - Must achieve full thumb abduction passively **ALWAYS release first web contracture** before or during adductor reconstruction. Chronic ulnar palsy develops tight adduction contracture. If not released, transfer will be too tight and thumb cannot abduct. **Step 2: Harvest EIP** - Same as Brand opponensplasty technique - Harvest EIP from index finger dorsum - Divide at insertion, free proximally **Step 3: Route EIP** - Route around radial wrist (similar to Brand) - Or route through intermetacarpal space (2nd web) - Goal: reach ulnar base of thumb proximal phalanx **Step 4: Insert Into Adductor** - Identify adductor pollicis insertion - Ulnar base of thumb proximal phalanx - Weave EIP into adductor insertion - Or bone tunnel if tendon quality poor **Step 5: Tensioning** - Thumb adducted to side of index finger - Thumb IP extended (NOT flexed) - Gentle adduction force, not excessive - Wrist neutral **Rehabilitation:** - Thumb spica 3 weeks - Active adduction exercises week 3 - Strengthening week 6 - Full function 3-6 months **Outcomes:** - Eliminates Froment's sign in 90% - Improves key pinch strength 50-80% - High patient satisfaction - Essential for writing, tool use ### Alternative: ECRL-to-Adductor **When to Use:** - Stronger donor needed (ECRL stronger than EIP) - Combined nerve palsies - EIP not available **Technique:** - Harvest ECRL (or use ECRB) - Requires tendon graft (palmaris or plantaris) - Route from dorsal forearm through interosseous membrane - Graft to adductor insertion - Tension as above **Advantages:** - Stronger donor (M5 typically) - More power for heavy work **Disadvantages:** - Requires graft (more complex) - Loses wrist extension strength **Froment's sign** = thumb IP flexion during key pinch (attempting to compensate for lost adductor pollicis with FPL). Pathognomonic for ulnar nerve palsy. Restoring key pinch often MORE important than correcting clawing for patient function. ### Combined FDP and Intrinsic Loss **High ulnar palsy** paralyzes both intrinsics AND FDP ring/small fingers. **Clinical Features:** - LESS clawing than low ulnar (paradoxical) - Lost ring/small finger DIP flexion - Weak grip strength - All intrinsic deficits (Froment's, weakness) **Ulnar Paradox Explained:** - Low ulnar: Intrinsics lost, FDP intact → severe clawing - High ulnar: Intrinsics AND FDP lost → less clawing (no FDP to flex IP) - Counterintuitive but well-documented **Reconstruction Strategy:** ### Priority 1: FDP Ring/Small Reconstruction **Option A: Side-to-Side Tenodesis** (Most Common) - Suture FDP ring/small to FDP middle (median-innervated) - Simple procedure - Allows mass finger flexion - Loses independent ring/small flexion (usually acceptable) **Technique:** - Volar wrist/palm incision - Identify all FDP tendons - Side-to-side suture FDP ring/small to FDP middle - Tension: equal resting position - Non-absorbable suture **Option B: ECRL-to-FDP Transfer** - For patients wanting independent flexion - Use ECRL as motor - Tendon graft to FDP ring/small - More complex but maintains independence **Option C: Accept Deficit** - If minimal functional impact - Patient can compensate with mass flexion - Avoid surgery if symptoms mild ### Priority 2: Intrinsic Reconstruction **Considerations:** - May not need if FDP also lost (less clawing) - Evaluate clinically after FDP reconstruction - If significant clawing persists, proceed with intrinsic transfer **Options:** - Zancolli lasso (if FDP reconstructed and functional) - Brand 4-tail (if want physiologic reconstruction) - Static tenodesis (simplest option) ### Priority 3: Adductor Pollicis **Always Address:** - Froment's sign present in both high and low ulnar palsy - EIP-to-adductor or ECRL-to-adductor - Often highest functional priority - Restore key pinch essential **Staging Strategy:** **Stage 1 (Initial):** - FDP reconstruction (side-to-side) - First web space release - Allow soft tissue equilibrium **Stage 2 (3-6 months later):** - Intrinsic reconstruction (if needed) - Adductor reconstruction - Assess results from stage 1 first **Benefits of Staging:** - Allows soft tissue healing between procedures - Can assess need for second stage based on stage 1 results - Reduces overall surgical time/anesthesia - Better patient tolerance **High ulnar palsy has LESS clawing than low ulnar palsy.** Seems counterintuitive but makes sense: low ulnar has strong FDP pulling IP joints into flexion (severe claw), high ulnar has NO FDP (less clawing). Classic exam question! ### Success Rates and Functional Results **Opponensplasty Outcomes:** - 85-95% achieve functional opposition - Pulp-to-pulp pinch restored in 90% - Strength 60-80% of normal - High satisfaction for independence in ADLs **Intrinsic Reconstruction Outcomes:** - Clawing corrected in 85-90% (Zancolli and Brand) - MCP hyperextension eliminated - Grip strength improves 30-50% - Cosmesis improved **Adductor Reconstruction Outcomes:** - Froment's sign eliminated in 90% - Key pinch strength improves 50-80% - Essential for writing, tool use - Very high patient satisfaction Tendon transfer restores **function**, not normal strength. Expect final motor grade M3-M4. Emphasize to patients that goal is independence, not athletic performance. Set realistic expectations preoperatively. ### Problems and Management **Intraoperative Complications:** **EDC instead of EIP, FDP instead of FDS** Prevention: - Confirm independent function before division - Anatomic landmarks (EIP ulnar to EDC) Management: - If recognized immediately, repair donor - May need to abort and use alternative donor **Radial artery, superficial radial nerve** Prevention: - Careful dissection around radial wrist - Protect nerve in subcutaneous tissue Management: - Primary repair if injured - Nerve repair or bury neuroma **Early Postoperative Complications (0-6 weeks):** - **Juncture rupture** (2-5%): Too early mobilization, inadequate weave - Presents as sudden loss of function - Requires reoperation and re-weaving - Prevention: 3-week immobilization, minimum 3 weaves - **Infection** (less than 1%): Rare with clean surgery - Antibiotics, possible washout - May compromise tendon healing - **Hematoma**: Inadequate hemostasis - Drain if symptomatic - Risk of adhesions **Late Complications:** **Over-tight intrinsic reconstruction** → excessive MCP flexion force → PIP hyperextension (swan neck). Difficult to correct - may need spiral splint, PIP tenodesis, or arthrodesis. **Prevention is key:** tension to MCP 70 degrees, NOT 90 degrees. ### When Initial Transfer Fails **Indications for Revision:** - Inadequate function despite optimal therapy (6+ months) - Juncture rupture within healing period - Persistent deformity (swan neck, claw) - Unacceptable donor site morbidity **Revision Options:** **1. Re-tensioning:** - If under-tensioned initially - Identify juncture site - Re-do Pulvertaft weave with correct tension - Immobilize again 3 weeks **2. Alternative Donor:** - If initial donor inadequate strength - Choose stronger donor (e.g., ECRL instead of EIP) - May require tendon graft for length **3. Tenolysis:** - If adequate transfer but adhesions limit motion - Free tendon from scar tissue - Early aggressive therapy postoperatively - Best results within 6-12 months of primary **4. Salvage Procedures:** - Arthrodesis (e.g., thumb IP for failed FPL transfer) - MCP capsulodesis for persistent clawing - Acceptance of deficit with adaptive equipment **Outcomes After Revision:** - Less predictable than primary transfer - Success rate 60-70% (lower than primary 85-90%) - Scar tissue limits outcomes - Set realistic expectations with patient **Prevention Better Than Revision:** - Careful patient selection - Meticulous surgical technique - Proper tensioning (most critical) - Adequate rehabilitation ## References 1. Brand PW. Biomechanics of tendon transfers. Hand Clin. 1988;4(2):137-154. doi:10.1016/s0749-0712(21)00622-3 2. Burkhalter WE. Tendon transfer principles and clinical applications in hand surgery. J Hand Surg Am. 1991;16(3):398-404. doi:10.1016/s0363-5023(10)80100-3 3. Anderson GA, Lee V, Sundararaj GD. Opponensplasty by extensor indicis and flexor digitorum superficialis tendon transfer. J Hand Surg Br. 1992;17(6):611-614. doi:10.1016/0266-7681(92)90026-e 4. Zancolli EA. Claw-hand caused by paralysis of the intrinsic muscles: A simple surgical procedure for its correction. J Bone Joint Surg Am. 1957;39(5):1076-1080. 5. Omer GE Jr. Tendon transfers in combined nerve injuries. Orthop Clin North Am. 1974;5(2):377-387. 6. Riordan DC. Tendon transfers in hand surgery. J Hand Surg Am. 1983;8(5 Pt 2):748-753. doi:10.1016/s0363-5023(83)80267-0 7. Hastings H 2nd, Davidson S. Tendon transfers for ulnar nerve palsy: evaluation and preoperative management. Hand Clin. 1988;4(2):167-178. 8. Boyes JH, Stark HH. Flexor-tendon grafts in the fingers and thumb: an evaluation of end results. J Bone Joint Surg Am. 1971;53(7):1332-1342. 9. Pulvertaft RG. Tendon grafts for flexor tendon injuries in the fingers and thumb: a study of technique and results. J Bone Joint Surg Br. 1956;38(1):175-194. doi:10.1302/0301-620x.38b1.175 10. Smith RJ. Intrinsic muscles of the fingers: function, dysfunction, and surgical reconstruction. Instr Course Lect. 1975;24:200-220.

Tendon Transfers for Median and Ulnar Nerve Palsy

Tendon Transfers for Median and Ulnar Nerve Palsy