Download Thumb reconstruction

Thumb Reconstruction
Basics
Goals
1. sensation
2. stability
3. length
4. mobility
5. position
6. pain-free function.
7. Additional pertinent factors include strength, aesthetics, and durability.
 Stability more important than mobility - the other digits can compensate for an
immobile thumb, but not for an unstable thumb.
Reconstruction
 Whenever possible, replantation or revascularization of the thumb should be
performed, as the outcomes of this treatment are superior to any secondary
reconstruction
 helpful to organize the various surgical options according to the level of
amputation, i.e., the distal, middle, and proximal thirds of the thumb ray.
Distal third
 Described as the “compensated amputation zone”
 Functional impairment in this zone is minimal
 aim to restore skeletal stability with painless, sensate well padded skin
 Options
1. Healing by secondary intention
2. Skin grafts – less durable
3. Composite grafts
i. Toe pulp
4. Local flaps
i. Homodigital
 Random VY
 Pulp transposition flaps
 Proximally based – turnover
 Laterally based
 Moberg (bipedicled)
 Ventkataswami VY advancement (unipedicled)
 Segmüller flap
 Reverse flow islanded digital artery flap
 Switch flaps
ii. Heterodigital
 cross-finger flaps (dorsal or volar)
 hypothenar flaps
 neurovascular island flaps
 innervated cross-finger flaps
5. Free flaps
i. Free pulp
ii. Free toe transfer
Switch flaps
 In hemipulp injuries involving the dominant (ulnar) sensory side of the thumb, the
radial hemipulp may be switched as an islanded or simple transposition. Secondary
defect is grafted.
Neurovascular VY advancement flaps
 Modification of the VY flap incorporating 1 or both the NV bundles
 Segmüller flap
o bilateral Kutler flap with vascular bundles
 Venkataswami flap
o VY flap based on 1 vascular bundle with the leading edge of the flap
extends across the palmar surface of the finger.
o advancing edge of the Venkataswami flap furthest from the pedicle is
denervated.
Adipofascial turnover flap
Moberg – palmar advancement flap
 advantage of bringing well innervated palmer thumb skin
distally to restore defect with nearly normal sensory
perception, durable skin and subcutaneous tissue.
 May close up to 2cm defects, MPJ and IPJ may need to be
flexed 30-45 to released tension on the flap and
neurovascular bundles.
 Additional movement can be made by
i. Proximal transverse releasing incision and secondary defect grafted
ii. addition of a 'V' tail proximally instead of a skin graft at the base of the
thumb (VY closure) – O’Brien modification
iii. Z-plasties into the midaxial incisions
iv. Burow's triangles at the flap base
 Advantages
1. normal innervation
2. well padded
 Disadvantage and complications include:
1. Flaps cannot be safely mobilized for more than 2.5 cm or approx 50% of the
digital fat pad.
2. Possible compromise of vascularity of the ungual area.
3. Flexion contracture
4. no danger in raising Moberg-type flaps on the thumb, as the dorsal skin of the
thumb has a separate blood supply (see below). However, on the fingers, there
is a risk of loss of the dorsal skin if the lateral incisions of the palmar flap cut
the dorsal branches of the digital arteries feeding the dorsal skin. Kojima
described preserving the dorsal branches.
Brunelli Dorsoulnar flap
 used to cover dorsal defects
 flap can be pedicled distally at 2 levels
1. at the level of the proximal nail fold arcade when the latter has been
conserved, ie, for cases of distal amputation, loss of palmar substance, or loss or
dorsal substance (dissection of the pedicle must be limited to 1 cm from the
nail cuticle),
2. at the most proximal level constituted by the palmar anastomosis for cases of
more proximal amputations, where the flap is used to cover the stump
(dissection of the pedicle should be limited to 2.5 cm from the cuticle).
 May be harvested with a dorsal nerve for neurorraphy with volar branches
Cross Finger Flap
 will provide satisfactory cover and usually adequate sensory recovery.
 Best to use middle or ring fingers
 Advantages
1. Satisfactory sensory return has been found in cross finger flaps
2. well tolerated
3. Sufficient padding for long term heavy use
 Disadvantages and complications include
1. Defect on the dorsum of the index finger.
2. Joint stiffness and web contracture.
Neurovascular Island pedicled flaps
 Indicated when there is irreparable damage to the digital nerves resulting in loss of
sensation to the thumb.
 Options are volar or dorsal
Volar NV island pedicled flaps (Littler)
 Based on ulnar side of middle finger
 If median nerve damaged, consider ulnar side of ring finger
Dorsal Radial innervated NV island pedicled flaps (Foucher)
 Based on 1st dorsal metacarpal artery and radial nerve branch
 Artery may run superficial to fascia (75%), deep to fascia (15%) or 2 branches –
one deep, one superficial(10%)
 May be dually innervated by anastamosing the contralateral (ulnar side)
Free toe pulp/nail transfer
 lateral aspect of the great toe pulp, and if nail required becomes very similar to a
toe wrap-around transfer
 usually, the dorsal digital artery, dorsal cutaneous vein, and digital nerve will be
used for anastomoses. At first, about a 4-cm incision is made on the dorsum of the
first web in the foot to expose the dorsal digital artery, dorsal cutaneous vein, and
digital nerve.
 In cases of the nail flap without hemipulp, nerve anastomosis are not required. But
if the elevated nail flap combines with the hemipulp and plantar skin, nerve
anastomosis must be performed to reconstruct the fingertip sensation.
 average dynamic 2 P.D. achieved was 9.6 mm.
 pain and hypersensitivity limited the usefulness of some reconstructed thumbs and
cold intolerance was frequent (73%).
Free nonvascularised composite nail grafts (PRS June 2000)
 harvested nail graft, which includes germinal, sterile, and dorsal roof matrix along
with the nail, is inset by using 7-0 chromic sutures
 10 cases (mean follow-up of 1.8 years) - two excellent, three good, two fair, and
three poor outcomes.
Left) Planned dimensions of donor nail graft from second toenail. (Center) Harvest of
nail graft, including nail bed and nail plate with both sterile and germinal matrix and
dorsal roof. (Right) Inset of free nail graft to periosteum of the dorsal thumb following
resection of scarred nail bed.
Middle Third
 Loss of length proximal to the mid potion of the proximal phalanx creates
problems with dextrous pinch and strong grasping of large objects.
 most thumbs retain acceptable CMC rotation and an adequate thumb index cleft.
 Additional requirement is added length
1. deepeding 1st web space
2. add bony length
Distal Middle Third
1. Deepen and widen the first web space
a. Z-plasties (simple, four-flap, or five-flap)
b. dorsal rotation flaps
c. remote pedicle flaps
d. regional flaps
e. free flaps.
f. Distraction osteogenesis
First Web Space Release
 Methods
1. release of skin
2. release of adductor and 1st dorsal interossei fascia
3. release of bony origins of 1st DI
4. release of volar beak ligament, 1st CMC capsule may be required
 May need to maintain reduction with Kwire or ex fix
 For severe contractures, this may be necessary for at least 2 to 3 months.
Z-Plasty
 4 flap best
 Adequate to achieve web space deepening when
1. At least half the prox phalanx remains
2. The skin is minimally scarred
3. The first metacarpal is mobile
4. There is no muscle contracture
Dorsal rotation flaps
Axial bilobed pseudokite flap
 Based on 1st dorsal metacarpal artery
Cross Arm flap
Remote Pedicled Flaps
 Distally based flaps used include
1. Radial forearm flap
2. Posterior interosseous flap
3. Ulnar forearm flap
Free flaps
 Classic flaps used for web space are
1. free groin flap
2. free lateral arm flap
3. anterolateral thigh flap
4. dorsalis pedis
5. temporalparietal fascia free flap
6. scapular-parascapular flap
Proximal Middle Third
 Addition of added 2cm in length may substantially improve the function.
 Options
1. Toe to thumb transfer
2. Pollicisation of an injured or partially injured digit
3. osteoplastic reconstruction
 bone graft covered by a tubed pedicle flap and the addition of the island
pedicle flap
4. cocked hat flap metacarpal lengthening techniques
5. Distraction
Distraction osteogenesis (Matev)
 unilateral external fixator.
 learning curve associated with a high complication rate and prolonged treatment
 Prerequisites:
1. a minimum of two-thirds of the metacarpal diaphysis should be present,
2. there should be good soft tissue coverage of the stump
3. at least protective sensation.
4. compliant patient
 Most surgeons recommend use of bone grafts noting that spontaneous union and
consolidation of the zone of distraction was unpredictable and took too long.
 Average period of distraction and consolidation is 6 months in most series
 two-point discrimination of 10 mm in the reconstructed thumbs - comparable to
those after toe-to-thumb transfer and/or the use of an osteocutaneous neurosensory
flap
 main complications related to this technique involve pin migration or loosening
and pin-tract infections.
Method
 thumb metacarpal is exposed through a dorsoradial incision
 periosteum is split but left in continuity
 Paired threaded external fixation pins (2.5 mm) are drilled perpendicular to the
longitudinal axis in a dorsal to palmar direction through both cortices of the
proximal and distal ends.
 Osteotomy performed at midportion of phalanx
 osteotomy is immediately distracted by 0.5 cm to ensure proper movement of the
bone fragments and then closed again to bring the bone ends back into contact.
 If a portion of the proximal phalanx is present, a longitudinal K wire is passed
across the metacarpophalangeal joint to prevent a progressive flexion
contracture developing during the distraction-lengthening phase.
 Gradual lengthening begins 7 days after surgery when postoperative pain and
oedema have subsided.
 The patient is instructed to distract the device by 3 to 4 turns (1 mm) per day.
 If the patient experiences discomfort or there is evidence of vascular
compromise to the distal skin or soft tissues, the distraction is reversed until the
discomfort and blanching resolve.
 patient remains in the external fixator until radiographs show consolidation of
thumb metacarpal.
 Secondary procedures include z-plasties to deepen the web space as well as
aesthetic reconstruction with digital prostheses.
 Length of distraction 2-4cm
Pollisication of the injured index digit
 four basic principles:
1) transposition of the digit on its neurovascular pedicle;
2) skeletal realignment;
3) muscular stabilization;
4) appropriate incisional design.
 Extensor and flexor tendons left attached
 Positioning the index finger
a. Rotation of 120-140 along its long axis
b.15 degrees of radial abduction (extension)
c. 35 degrees of palmar abduction
 Secondary reconstruction include shortening of flexor tendons, tenolysis of
extensors and opponensplasty if all the thenar muscle function lost and
satisfactory CMCJ is retained
Pollicisation of the injured middle finger
 EPL reattached to the MF EDC
 Flexor tendons left intact
 Index and ring fingers are reaprroximated by suturing their opposing deep
metacarpal ligaments together.
Gilles Cocked Hat flap
 Incision that begins dorsally and extends around the base of the thumb at the level
of the CMC joint to terminate palmarly just distal to the edge of the thenar
musculature in line with the index finger.
 corticocancellous bone graft 5 cm long is taken from the iliac crest and fashioned
such that 2-2.5 cm in length is used to augment the metacarpal
 The flap is draped across the bone graft and the proximal 2/3 of the metacarpal is
covered with FTSG or a SSG
Osteoplastic reconstruction
 Thumb reconstruction by means of a bone graft covered with a tube pedicle flap.
 Initial result was not considered satisfactory as they failed to provide sensory
perception.
 The incorporation of island pedicle as part of reconstruction has improved results
 Typically, these methods provide relatively poor sensation.
 Unless vascularized bone is used, resorption is common.
 Moreover, the resulting thumb is usually bulky and has a poor aesthetic
appearance. Most osteoplastic methods require multiple operative stages and do
not provide any mobility. Finally, all of these techniques create some degree of
donor-site morbidity.
 Types
1. Two staged pedicled flap with NV island flap
2. One stage radial forearm flap with NV island flap (Foucher)
3. One stage dorsalis artery free flap (Doi)
Staged osteoplastic reconstruction with Littler-type neurovascular island flap
 Due to the excellent blood supply of the groin flap, partial division of the flap and
ligation of the superficial circumflex iliac artery is recommended at 4 weeks.
 Problems include donor morbidity, perception of thumb as middle finger, bone
resorption, failure of bone graft, flap necrosis
Composite radial forearm island flap
 1 stage osteoplastic reconstruction
 Small branch from radial artery to pronator quadratus identified and mobilised to
include this within the area of osteotomy.
 Graft 2-4cm long, need width of 1.5cm, 7-8mm thick.
 Requires Little flap for volar reconstruction
Proximal third
 require the addition of at least 5 cm of length
 At the very least, provide a stable and sensate post for pinch and opposition
 Mobility of the reconstructed thumb is a secondary consideration
 Options
1. transfer of an injured digit
2. Pollicization
3. Free toe transfer
Pollicisation of normal digits
 Advantage of single-stage operation that provides nearly normal sensation and
vascularity immediately, with some functional joint motion
 IF, MF, RF, LF have been used.
 Most favour pollisation of the index digit,
1. Technically simpler
2. No palmar scars
3. Allows deepening of the 1st web space
4. Origin of the adductor pollicis is preserved.
5. Aesthetic appearance of the pollicized index finger is better than that of the
other digits, as there is no void at the donor site
 Pollicisation of the middle finger is associated with the problems of rotation and
overriding of the index and ring fingers
 Some recommend the ring finger as index is too long and is a major prehensile
finger. If the index finger is not available, RF is next best.
 If CMCJ is intact, fix IF proximal phalanx base to base of remnant thumb
metacarpus
 If CMCJ is not intact, the fix IF metacarpal neck to trapezium, ensuring MCPJ is in
hyperextension.
 The common digital nerve must be separated intraneurally to allow untethered
transposition.
 EDC may be shortened or plicated or sutured to EPL
 AdP is reattached to the first volar interosseous tendon (ulnar side), and the thenar
intrinsics are reattached to the first dorsal interosseous and lumbrical tendons
(radial side)
 pollicized digit should be positioned in extension and palmar abduction,
opposition, and pronation.
 Secondary procedures may be required to shorten the flexor tendons, to perform an
extensor tenolysis, or to perform an opponensplasty. Extensor tenolysis may be
avoided by transferring the extensor tendons intact.
 There is a tendency toward hyperextension at the metacarpophalangeal joint
after transfer.
 This tendency can be minimized by longitudinally severing the extensor hood
and keeping the joint flexed with a K-wire postoperatively
Microvascular toe transfer
 O'Brien's successful use of the dorsal vascular system and Gilbert's landmark
anatomic study of the vascular anatomy of the first dorsal metatarsal artery
popularized the use of the dorsal system.
 Ultimately, greater success has been achieved using the dorsal system than the
plantar system
 n 1980, Morrison described the technique of the wraparound toe transfer, which
allows a customized thumb reconstruction and preserves elements of the great toe
 outcomes with toe transfers are generally very good - patients who had undergone
toe transfer had higher functionality and aesthetics scores when compared with
patients who had not undergone any reconstruction for their proximal thumb
amputations
 donor-site morbidity of the foot was negligible, and that there was no
diminishment in lower extremity function
 ideal in children, since the growth potential of the toe is preserved.
Timing of reconstruction
 can be performed as a primary procedure with an open wound or as a secondary
procedure after the wounds have healed.
 Early and single-stage reconstruction are preferred if the patient's and the wound's
conditions are suitable.
 This includes simultaneous reconstruction of the thumb and fingers if needed.
 The results in terms of survival, immediate and late complications, and the need for
secondary procedures have been shown to be similar between primary and
secondary reconstruction
Anatomy
Morphology
 great toe transverse diameter is about one third bigger than the thumb.
 All great toe phalanges are slightly longer than those of the thumb;
 its toenail is also bigger and there is more subcutaneous tissue in the pulp.
 The lesser toes are shorter than the digits and have a square shape at the distal
ends. The joints have limited flexion and also have a tendency to claw.
Blood supply
 anterior tibial artery continues as the dorsalis pedis artery on the dorsum of the foot
and runs laterally to the extensor hallucis longus tendon toward the first web space.
 Proximal to the base of the first and second metatarsals, it gives off the arcuate
artery, which provides the second, third, and fourth dorsal metatarsal arteries
 the dorsalis pedis artery bifurcates just past the base of the first and second
metatarsal, into the deep plantar artery and the first dorsal metatarsal artery.
 deep plantar artery (also known as the perforating or communicating branch)
courses downward between the first two metatarsals to contribute to the plantar
arch.
 The first dorsal metatarsal artery always passes dorsal to the deep transversal
metatarsal ligament.
 At this point it divides into medial and lateral branches, named as digital arteries
to the second and great toes, respectively, and a communicating branch to the
first plantar metatarsal artery (FPMA)
 first dorsal metatarsal artery bigger than FPMA in about 70% of cases,
plantar dominant in 20%, and in the rest both arteries can be of similar size
Drainage
 Veins leave the dorsal venous arch and converge medially to form the great
saphenous vein and laterally to form the small saphenous vein
 The plantar foot surface has a superficial and a deep venous system. The deep
veins originate from the plantar digital veins and communicate with the dorsal
digital veins by perforating veins.
Nerves
 dorsum of the foot is innervated from the sural, superficial, and deep peroneal
nerves. The plantar surface is innervated by the tibial nerve, which divides into the
medial and lateral plantar nerves supplying the medial three and a half toes and
lateral one and a half toes, respectively.
Method (FW Chen, Hand Clinics 2003 and PRS CME 2005)
Pre–toe transplant preparations
 All grossly viable tissues, including mobile joints and neurovascular bundles,
should be preserved as much as possible
 Adequate or even some redundant skin cover over the stump of the hand is
required and can be obtained with a pedicled groin flap before definitive
reconstruction.
 This additional skin is of use during later reconstruction, because it can cover the
lateral aspect of transplanted toes, protect the pedicle, or form a web space in the
hand.
 also allows less skin to be harvested from the foot, allowing direct closure of the
donor site.
 Local flaps should be avoided because resultant scarring may increase difficulty of
later reconstructive procedures.
 If the metacarpal length is deficient, distraction osteogenesis or a nonvascular bone
graft from the iliac crest can also augment it at the same time as soft tissue
reconstruction. This preserves metatarsal length and reduces donor site morbidity,
especially in the great toe.
Great toe harvest
 Indicated for amputations at the distal half of the metacarpal to the proximal
part of the proximal phalanx
 If shorter than this, bone graft or distraction first.
 ipsilateral toe should be used, if possible:
1. the pedicle is located in a favorable position for anastomosis in the recipient
site.
2. there is a 10- to 15-degree angulation at the metatarsophalangeal and
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interphalangeal joints of the toe that facilitates opposition of the transferred
ipsilateral toe to the fingers.
3. permits the use of skin from the first web space of the foot to reconstruct the
first web space of the hand
dissection begins in the dorsum of the first web space, where the junction of the
lateral digital artery of the great toe and the medial digital artery of the second toe
is identified.
In the dorsal-dominant arterial system, retrograde dissection continues until a
suitable length and diameter of artery are achieved.
In a planar-dominant system, plantar dissection is continued up to the middle
metatarsal shaft, where the union between the FPMA and toe dorsalis pedis artery
through the proximal communicating artery is located.
The FPMA is divided at this point, because further dissection of the
communicating branch might be tedious and destructive for the foot
During great toe harvest, it is advisable to preserve at least 1 cm of the proximal
phalanx to maintain the foot span, the appearance, and push off function of the
donor foot to prevent windlass effect.
Otherwise - removed at the metatarsophalangeal joint, preserving the volar aspect
of the head of the first metatarsal and the sesamoid bones to avoid gait disturbance
Second toe harvest
not the first choice for thumb reconstruction, because
has a smaller and bulbous contact surface
a tendency for clawing
a smaller toenail
inferior cosmesis
less ideal functions as compared with either a trimmed or total great toe
transplantation.
 In reconstruction of nondominant hands or for patients who are satisfied with
second toe looks and function, a second toe is a good selection.
 In proximal thumb amputations involving the metacarpal shaft, the great toe
transplantation is not advisable because of donor site morbidity considerations;
however a transmetatarsal second toe transplantation can be used
 DIPJt of the transferred second toe should be pinned in extension for 2 to 3 weeks
to prevent a mallet deformity.
 When the thumb amputation is at the proximal metacarpal level, an opposition
transfer will be required as a secondary procedure after second toe transfer
Insetting
 osteosynthesis is performed using interosseous wires
 extensor tendon is repaired with the interphalangeal and metacarpophalangeal
joints in full extension
 long flexor tendon is repaired with the flexor pollicis longus in the thumb
 Arterial anastomosis is to the radial artery in the anatomic snuffbox.
 Venous drainage of the transferred toe is usually provided by the dorsal venous
system. Ideally, a large superficial vein is anastomosed to the cephalic vein on the
hand. The deep branch of the peroneal nerve is harvested and connected to the
superficial branch of the radial nerve, while the proper digital nerves of the toe are
connected to the stumps of the digital nerves in the thumb.
Modifications
Trimmed great toe transplantation (FC Wei 1988)
 reduces the bony and soft tissue girth of the great toe to make it more equivalent to
the thumb, at the same time preserving the interphalangeal joint articulation
 indicated for thumb amputations at or distal to the metacarpophalangeal joint when
there is an obvious size discrepancy between the thumb and great toe
 contraindicated in children because damage to the growth plates can be incurred
during harvest of the toe.
 Trimming is done on the medial aspect, because the pedicle is located on the
fibular side.
 A medial flap is left on the toe, as in a wraparound harvest. However, 4 to 6 mm of
the medial border of the phalanges, joint prominence, and nail are also trimmed;
the toe is essentially made to match the size of the thumb by shaving off its medial
elements and leaving them in situ in the foot.
Toe wraparound flap(Morrison 1980)
 ideal for thumb amputations distal to the interphalangeal joint and for soft tissue
avulsion distal to the metacarpophalangeal joint with intact joint, skeleton,
and tendons
 In its original description, it consists of only the nail and soft tissue envelope of the
great toe without the skeleton and tendons, retaining the great toe
 The thumb skeleton, if not already preserved, needs to be reconstructed with a
nonvascularized iliac crest graft.
 The reconstructed thumb has no motion, nor does it have growth potential
 A normal carpometacarpal joint and good thenar muscles are required for success.
 subsequent modification of this technique included the distal phalanx for nail
support, which also prevented swiveling of the wraparound flap and grafted bone
fracture or absorption. Thus the bone graft is sandwiched between two
vascularized bones
 The soft tissue flap is designed on the great toe by matching the thumb
circumference, leaving a medial strip on the toe. The residual toe is then shortened
to allow closure with a medial flap and split thickness skin graft or cross toe flap.
transfer of individual toe components
 metatarsophalangeal or interphalangeal joint, with or without a skin flap
 skin of the first web space
 a nail with dorsal skin
 pulp
Multiple finger amputation
 Reconstruction of two fingers instead of only one has several advantages,
including a useful tripod pinch, stronger hook grip, enhanced lateral stability,
and increased handling precision
 options for adjacent amputated fingers include two separate lesser toe
transplantations or a combined second and third (or third and fourth) toe
transplantation on a single vascular pedicle.
 In amputations distal to the web space, two separate lesser toes are preferable
because transplantation of combined second and third toe creates an objectionable
sydactylous appearance
Metacarpal hand
 Multiple transfers may be required, such as a great toe for thumb and a combined
2/3 digit for fingers.
Prosthetics
 prostheses provide a greater benefit with more distal amputations.
 Surgical reconstruction is preferred if it will provide a superior improvement in
function (i.e., sensation), if it will be socially acceptable, and if the secondary
donor defects are justified by the quality of the end result.
 As a minimal requirement, at least 1 cm of the thumb proximal phalanx must
remain to allow prosthesis fitting; a 1.5 cm residual stump is ideal. Prosthetic
reconstruction for total thumb loss is suboptimal, requiring a glove to be worn over
the palm.
 osseointegrated prosthetics have been shown to provide better functional outcomes
in initial studies