- See:
- Digit Reimplantation
- Moberg Flap;
- Tendon Injuries of the Thumb:
- Second Toe Transfer:
- Skin Grafts: for hand defects;
- Management of Acute Injuries:
- amputations:
- replantation:
- w/ amputations through the thumb IP joint, consider replantation and fusion;
- amputation of the finger and hand:
- in contrast to amputations of a single finger, bone shortening and wound closure usually should not be considered for thumb soft tissue defects;
- in general, the thumb should never be shortened;
- dorsal defects:
- subcutaneous axial flap should be raised from the dorsal aspect of the proximal phalanx of the index finger;
- tip amputations with more loss dorsally require a V-Y advancement flap;
- palmar tip amputations:
- Moberg Flap
- w/ loss that is more palmar but less than two thirds of the pulp are ideal for a Moberg Flap:
- Crossed Finger Flap:
- w/ more than 2/3 of volar pulp loss, crossed finger flap from the index finger is appropriate;
- in this case, the flap will hinge off the radial side of the index finger;
- reference:
- Radial innervated cross-finger flap from index to provide sensory pulp to injured thumb.
- w/ loss that is palmar but is greater than 2/3 of the pulp should be treated with a neurovascular flap from the toe;
- Reconstructive Options for Established Injuries:
- level of injury:
- absence of thumb = 40% disability of hand as a whole;
- injury at IP joint;
- no reconstruction may be required but wrap around method may be considered;
- references: Reconstruction of the thumb with a free wrap-around flap
- injury to proximal phalanx (intact MP joint);
- w/ amputation distal to MP joint, only the long flexor and extensor are lost;
- whole great toe transfer, 2nd toe transfer, or wrap around may be considered;
- deepen thumb web by Z plasty;
- injury thru MP joint;
- great toe or 2nd toe transfer;
- injury thru metacarpal;
- proximal to the MP joint, the intrinsic insertions and progressively their muscle bellies
are destroyed which leaves only the APL functioning at the metacarpal base;
- pollicization or 2nd toe transfer (when indicated)
- w/ a distal metacarpal injury, consider great toe transfer w/ a small portion of MP joint;
- w/ more proximal metacarpal injury, use a 2nd toe transfer;
- injury at cmc level: pollicization;
- Specific Procedures:
- digit reimplantation
- toe to thumb transfer: (see: second toe transfer):
- may be indicated to reconstruct the thumb after amputations from the level of the metcarpal base to the IP joint;
- procedure is also indicated w/ hands w/ multiple injuries & amputations
- first vs second toe transfer:
- usually the second toe is preferable in children and athletes, or in patients concerned about the appearance of the foot (such as women who wear sandles);
- transferred great toe has a better appearance than the second toe;
- great toe often has poor flexion ability where as second toe has poor extension ability;
- great toe may confer about 1/3 of normal strength (second toe confers on 15% of normal);
- w/ amputation is proximal to the MP joint:
- there will no thumb intrinsic function which will thus require a tendon transfer;
- transfered MP joint tends to hyperextend and therefore must be restrained by capsulodesis or arthrodesis;
- disadvantages:
- technically difficult procedure;
- vascular comprimise of hand may preclude the procedure;
- an adequate soft tissue cover (free of scar) is necessary prior to considering the procedure;
- most patients will require preoperative excision of scar and flap coverage and most patients will require at least one additional operation following the transfer;
- sensation recovery is slow and incomplete (75% of patients may expect 2 point of less than 10 mm at two years)
- cold tolerance remains a problem for most patients;
- references:
- Free toe transfer for thumb and finger reconstruction in 300 cases.
- Ideas and Innovations: Toe-to-Thumb Transfer: A New Technique.
- Reconstruction of the hand with free microneurovascular toe-to-hand transfer: experience with 54 toe transfers.
- Toe-to-hand transfer.
- wrap around reconstruction:
- references:
- Reconstruction of the thumb with a free wrap-around flap from the big toe and an iliac-bone graft.
- Thumb reconstruction by the wrap-around method.
- Resurfacing of the donor defect after wrap around toe transfer with a free lateral forearm flap.
- lengthening:
- with distraction metacarpal lengthening up to a 105 per cent increase can be achieved over several weeks;
- alternatively, accept the distraction attained at surgery and insert a bone graft at the time;
- references:
- Thumb reconstruction after amputation at the metacarpophalangeal joint by bone-lengthening. A preliminary report of three cases.
- Thumb reconstruction after amputation at the interphalangeal joint by gradual lengthening of the proximal phalanx. A case report.
- The Gillies thumb lengthening operation.
- Thumb reconstruction through metacarpal bone lengthening.
- phalangization:
- converts the metacarpal into a phalanx allowing increased space for grasp;
- muscle recession:
- first dorsal interosseous is recessed by releasing the portion which arises from the thumb metacarpal;
- reattach adductor insertion from the sesamoid at the MP joint to a point further proximal on the metacarpal shaft;
- deepening of the skin of the first web space:
- achieved w/ z-plasty (place on limb along the volar thenar crease, another along the ridge of the web space, and the last limb over the dorsum of the first metacarpal;
- pollicization:
- indicated for proximal thumb metacarpal amputations;
- advantages:
- good appearance;
- potential for motion at all joints in the thumb;
- good sensibility;
- disadvantages:
- a ray is removed which narrows the hand;
- expect some loss in grip strength;
- most patients w/ require more than one operation (such as web space deepening, tendolysis, rotational osteotomy);
- flap comprimise:
- may arise from damage sustained at the original trauma;
- consider arteriogram to determine vascular anatomy;
- incomplete digit rotation / insufficient web space:
- may result from scarring on the radial side of the hand, in which case, patients should be managed w/ appropriate soft tissue transfer to eliminate scarring;
- inadequate first dorsal interosseous muscle:
- the first dorsal interosseous muscle will function as an opponens, and if it has been damaged, then a ring-FDS opponensplasty may be required;
- references:
- Thumb reconstruction by digital transposition.
- Pollicization after traumatic amputation of the thumb.
Reconstruction of the thumb.
Reconstruction of the thumb with a free wrap-around flap from the big toe and an iliac-bone graft.
Per Primam thumb replantation for all patients with traumatic amputations.
One hundred eleven thumb amputations: replantation vs revision.
Survival factors in replantation and revascularization of the amputated thumb--10 years experience.
The choice of procedure following thumb amputation.
Thumb reconstruction through metacarpal bone lengthening.
Dorsal pedicle flap for resurfacing a moderate thumb-index web contracture release.
Medical and surgical importance of the arterial blood supply of the thumb.
Arterial anatomy and clinical application of the dorsoulnar flap of the thumb.