Thumb reconstructionChapter 87Charles J.Eatonp. 835~p. 846Pang-Yun Chou02.15.2012
History• Staged, pedicled toe-to-thumb transfer– without microvascular anastomosis– performed by Nicoladoni in 1898• Phalangization• Osteoplastic reconstruction• Pollicization• Pedicled digital transfers– date back 100 years• Digital neurovascular island flaps and free toe transfers– developed 50 and 40 years ago
Indication• A replanted thumb, seems to be the best possiblereconstruction– Not always more functional than an amputationproperly revised at the same level• Strong contraindications– significant vascular disease– short life expectancy– chronic pain with disuse of the limb– unreconstructable sensory loss– unrealistic patient expectations
Evaluation• What is the status ofthe basal joint?– CMC joint evaluatedclinically andradiographically– salvage by arthroplastyA: Interphalangeal arthrodesisB: Metacarpophalangeal arthrodesisC: Soft-tissue arthroplasty of the carpometacarpal joint
Evaluation• Is there a first web spacecontracture or skin deficit?– unappreciated skin loss– scar contractures– abductor muscle destruction– Paralysis– basal joint pathology– adductor/flexor musclecontracture• Preliminary correctionshould be considered– often cannot be fullycorrected, even withdetermined surgical efforts Release with reverse pedicled posteriorinterosseous artery island flap.
Evaluation• Are there problems with the remaining digits?– Optimum length, mobility, and position of the thumb are alljudged with the remaining fingers• Has the patient developed maladaptive patterns of use?• Do the patient’s complaints match the apparent deficit?– Thumb amputation less restricted use of the hand– Crush/avulsion injuries may result in a wide zone of deepscarring, with prolonged stiffness, swelling, intrinsic tightness• What are the patient’s expectations?– Function, then social presentation and aesthetics– A technical triumph to the surgeon• may be seen as a grotesque deformity by the patient
Type of deficiencies• Thumb deficiencies– Amputation– Component loss• Reconstruction– emergency (possible replantation)– urgent (fresh open wound)– subacute (unhealed wounds)• septic or flap-threateningcomplications are greatest– elective (healed wounds)• Reconstructive priorities– first healing– then function
Component loss• Skeletal injuries– Anatomic reduction and fixation– Nonreconstructible IPJ & MPJ treated with arthrodesis,but CMCJ best salvaged with soft-tissue arthroplasty• Soft-tissue loss– Skin grafts or flaps• Composite loss– urgent soft-tissue cover with skeletal stabilization andpossible bone grafting• As with any mangling limb injury, the best time toproceed with completion of amputation is at the firstoperation
Component loss• Because sensory perception is key toeffective use of the thumb, innervatedflaps are much preferred for contactarea resurfacing• Innervated flaps– Moberg palmar adv. flap– Holevich FDMA flap from index– Heterodigital N-V sensory “island” flaps– Free finger or toe pulp flaps• Standard local digital flaps– V-Y adv.– Dorsal or volar cross-finger flaps• Noninnervated regional flaps– Posterior interosseous– Radial forearm and intrinsic muscle flaps
Holevich flapThe dorsal index finger skin may be mobilized on a narrow skin or subcutaneouspedicle for transfer to the thumb. This flap has been used to resurface the distalhalf of the palmar skin, including the entire pulp surface
Free pulp transferEmergency thumb pulpresurfacing with free pulp flapharvested from a ring fingeramputated in the sameaccident.A: Initial injury withamputated ring finger and lossof thumb soft tissue.B: Tissue harvested fromamputated part.C: Thumb after flap transfer.
Component loss• If circumferential soft-tissueloss extends proximal to thebase of the proximal phalanx– Distal phalanx eventuallyavascular necrosis despite flapcover primaryinterphalangeal disarticulationshould be considered• Denuded skeleton should becovered in a tubed or closedflap not buried in a pocketCircumferential thumb resurfacing withcontralateral free radial forearm flap
Amputation• Wheneverpossible, replantation shouldbe considered for thumbamputation.• Amputation Distal to theMetacarpophalangeal Joint– Primary reconstructive goals arelength, stability, and adequateweb space– Choices• bone graft with a local flap• osteoplastic reconstruction• Phalangization• distraction lengthening• toe-to-thumb transfer
Amputation• Amputation Proximal to the Metacarpophalangeal Joint– thumb ray does not project beyond the web space skin• Options when loss is through the distal metacarpal– osteoplastic reconstruction– pedicled finger remnant transfer– Pollicization– free toe transfer• A proximal metacarpal amputation– retains the basal joint but has no intrinsic muscles.• With this or an amputation including the basal joint– (a) if the fingers are functioning well• provide a stable, static post to oppose the fingers– (b) full-finger pollicization
Osteoplastic Thumb Reconstruction• Best Indication/Unique Advantages– Partial or distal subtotal amputation– No digit is sacrificed• Disadvantages and Special Requirements– Multiple staged procedures– Results may be unaesthetic• bulky, floppy, No nail– Additional neurovascular flap for sensibility
Osteoplastic Thumb Reconstruction• Technique– Combination of a bone graftand flap to lengthen the thumbremnant– Three procedures– Lengthening the skeleton withan iliac crest bone graftcovered in a tubed distant flap– Division– Transfer of a neurovascularsensory island flap from theulnar side of the middle fingerPartial amputation, lengthened with an iliaccrest bone graft wrapped in a tubed pedicledinferior epigastric flap. Innervation with aneurovascular sensory island flap transferred
Phalangization• Best Indication/Unique Advantages– Thumb lengthening by finger transfer is a possibleconsideration (rare) if the thumb is nearly longenough, such as base of proximal phalanx– Usually this is a single-stage operation• Disadvantages and Special Requirements– Not provide much functional improvement– Very unnatural appearance• Particularly if the web is converted to a cleft by an aggressiveZ-plasty.
Phalangization• This is a web-deepening procedure, results of which are so oftendisappointing that it is rarely a good recommendation in view oftoday’s alternatives• To allow creation of the cleft– Adductor muscle insertion is detached and repositioned proximally– First web space is deepened with a Z-plasty– Correction of an associated first web space contracture• Require stripping of the entire ulnar border of the first metacarpal• Capsulotomy of the basal joint.– The mechanical advantage of the adductor is progressively lessenedwith more proximal reattachment
Metacarpal Distraction lengthening• Best Indication/Unique Advantages– Distal subtotal amputation (region of [MCP] joint)is an indication for this procedure and there islittle or no donor defect except scar.• Disadvantages and Special Requirements– Only limited lengthening is possible– Absolute cooperation is required
Metacarpal Distraction lengthening• Thumb’s metacarpal is lengthened using progressive adjustments of anexternal fixator in the manner introduced by Ilizarov for the lower limbs– Metacarpal exposed– Fixator placed• Corticotomy made circumferentially and subperiosteally through the metacarpal shaft• Minimize medullary bone disruption– After 1 week, distraction is begun at a rate of 1 mm per day– MCP joint will be progressively flexed unless stabilized with a strong K-pin• In small children– new bone growth from the periosteum– medullary bone may adequately fill in the distraction gap• In adult– Interposition bone grafting is usually required
Metacarpal Distraction lengthening• Traumatic MCP level thumbamputation– Covered in a groin flap• Metacarpal corticotomy• Distraction fixator to lengthenthe metacarpal• Interpositional bone grafting• A: Distractor applied.• B: After lengthening.• C: Bone graft placement.
Thumb lengtheningOptions for lengthening a partial or distal subtotal thumb amputationwith the least donor-site morbidity include (A) osteoplastic reconstruction, (B)phalangization, and (C) metacarpal distraction lengthening.
On-Top Plasty• Best Indication/Unique Advantages– Amputation in the area of the MCP joint is anindication for this procedure, which will enhance thevalue of a damaged finger• Disadvantages and Special Requirements– The appropriate finger is infrequently available, andthis procedure narrows the palm– Transferred injured parts carry a higher risk of acomplication
On-Top Plasty• Neurovascular pedicle transfer of the distal segment of adamaged finger to lengthen the thumb.• Removed by ray resection maybe needed.• Pre-op arteriography may be helpful.long thenal thumb and middle finger ray resection
Pollicization• Best Indication/Unique Advantages– The best indication is proximal subtotal or totalamputation.– This procedure is the only satisfactory means ofbasal joint reconstruction and results inextensive physiologic sensory restoration.• Disadvantages and Special Requirements– This procedure narrows the palm.
Pollicization• Pollicization refers to the neurovascular pedicle movement of a finger,often with its metacarpal– For congenital absence of the thumb– The index finger is resected at the second metacarpal base– Pronated : 130 degrees and projected in palmar abduction at its fixed base– Dorsal or palmar skin into a web between middle finger and new thumb– Extensor tendons must always be shortened as part of the primary procedure– Flexor tendons follow a circuitous route, and length adjustments– Structures receive new identities:• EDC APL• EIP EPL• First dorsal interosseous APB• First palmar interosseous adductor pollicis• Metacarpal head and the proximal and middle phalanges trapezium and themetacarpal and proximal phalanges, respectively
Pollicization• Preservation of intactnerves for critical sensibility• Secondary surgery will beneeded for approximately50% of patients undergoingpollicization, yet in theright circumstances and forthe right indication, resultswill be superior to that ofall other availablealternatives.
Toe-to-Thumb• Best Indication/Unique Advantages– Performed when most of a well controlled firstmetacarpal is present but length is needed– Advantages include• (a) Good level of sensory recovery• (b) Bone growth continues• (c) Single-stage operation• Disadvantages and Special Requirements– Foot disability may occur– Thumb always looks like a toe
Toe-to-Thumb• Skin deficit on the hand– Recipient site has skin grafts ortight scars– Adequate soft tissue prior tothe transfer operation• Pre-op arteriography of thehand and foot recommended• Skeletal reconstruction forcorrect length is tailored tomatch the defect.– Second toe transfers favoredfor children– Great toe transfers favored foradults
Toe-to-Thumb• Toe-to-thumb operations– One or two teams.– Level of toe osteotomy lengths of skin, tendons, nerves, and vessels– Recipient vessels explored first define donor pedicle length.– The radial artery is preferred.– A racquet-shaped incision, which gives more dorsal than plantar skin.– Veins are dissected first, elevating thin skin flaps proximally– The dorsalis pedis and first dorsal metatarsal artery are dissected– The plantar digital nerves are small and short compared to those ofthe thumb– Tendons are severed proximally to allow tendon repairs
Toe-to-Thumb• Normal MTPJ range of motion is hyperextended relative to thethumb MCPJ.• If the MTPJ is included in the reconstruction– Oblique metatarsal osteotomy used to increase flexion for morenatural thumb function.• Although the reconstructed thumb is usually pronated– the degree is determined for each case to function best withremaining fingers.• If opponensplasty is needed– performed as a primary or secondary procedure.• Second toe donor sites closed primarily– facilitated by resection of the second metatarsal.• Great toe donor-site closure often requires a skin graft.• Donor-site morbidity is small, but cannot be dismissed entirely
Wraparound Toe Transfer• Best Indication/Unique Advantages– For amputation near the MCP joint or distal to it, thisis the procedure of choice.– It results in the most normal-appearing reconstructionfrom the foot.• Disadvantages and Special Requirements– This technically complex and demanding procedureresults in limited functional improvement when usedwithout an MCP joint.– It requires an iliac bone graft.
Wraparound Toe Transfer• Wraparound toe transfer– Hybrid of great toe transfer and osteoplastic reconstruction– Great toe is filleted– The isolated free flap• Distal half of the distal phalanx with the plantar, lateral, dorsal tissues, and toenail.– This complex is wrapped around a bone graft– The donor-site defect is closed– The ultimate fingernail is narrowed– No tendon repairs.Modified wraparound greattoe transfer for a deglovinginjury