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Terzis and Kostopoulos reported 14 lower extremity in University of Wisconsin solution before engraftment.
[82]
nerve injuries in 12 patients that had been reconstructed The immunosuppressive regimen in the first 3 patients
with VNGs. The common peroneal nerve (CPN) was injured consisted of triple therapy with cyclosporin A (CsA),
in 12 patients and the posterior tibial nerve in 5 patients. Imuran, and prednisone. The subsequent 4 patients
The repair of CPN lesions was not recommended given were treated with FK506, Imuran, and prednisone.
the poor prognosis following nerve reconstruction. [77,83] Immunosuppression was withdrawn sequentially,
The vascularized sural nerve graft was used as a pedicled beginning with prednisone. After the Tinel’s sign had
nerve graft based on the superficial sural artery or progressed into the distal segment of the reconstructed
as an arterialized‑venous nerve graft based on the nerve, CsA or FK506 was withdrawn. No significant
lesser saphenous vein. Kim and Kline found that good complications secondary to systemic immunosuppression
functional recovery could not be expected with a graft have occurred. Six of the 7 allografts were clinically
length greater than 12 cm. It has been reported that in successful based on the recovery of sensory and/or motor
[84]
the lower extremity all patients with nerve grafts greater function in the reconstructed distribution. One patient
than 6 cm in length had fair or poor results. Grade 3 rejected his allograft.
[79]
function was recovered in 38% of patients with grafts Although some patients have recovered motor function,
6‑12 cm and in only 16% of patients with graft lengths sensory recovery has been more consistently observed.
[85]
of 13‑24 cm. In contrast, with VNGs of 13 cm or more, Similarly, the predominance of superior sensory (temperature
grade 3 function was recovered in 66.67% of patients. and pain) over motor (intrinsic) recovery has been
Terzis and Kostopoulos showed statistically significant described in hand transplant recipients. It is yet to
[82]
differences (P = 0.008) for CPN injuries between patients be determined if this occurs secondary to differential
who underwent surgery within 6 months from the time of sensory (particularly sympathetic) nerve regeneration,
injury and patients who presented later than 6 months. sensory‑motor mismatch, or end organ (muscle) lack of
Preoperative and postoperative differences in dorsiflexor receptivity to reinnervation. [88]
muscle strength were statistically significant (P < 0.001).
A correlation between outcome and type of injury and
between outcome and age was not found. COMPARISON OF DONOR SITES IN THE
UPPER AND LOWER LIMBS
In lower extremity nerve injuries, when a VNG is
indicated, the best choice is the sural nerve, either as a Ideally, donor nerves for free vascularized nerve transfer
pedicled nerve graft based on the superficial sural artery should exhibit a type A, B, or C pattern. Type A represents
[7]
and or as an arterialized venous nerve graft based on the a nerve supplied segmentally by a long unbranching artery.
lesser saphenous vein [Table 6]. Type B is similar to type A except that the nerve divides

Vascularized nerve allografting early. Type C is similar to type A, but the artery courses
The use of nerve autografts is limited by the availability on the surface of the nerve instead of in parallel and gives
of suitable donor sites. Allografting in reconstructive several branches to the nerve that can subsequently be
surgery has became more promising with advances in divided into multiple vascularized segments.
immunosuppression therapy. Mackinnon et al. have Upper limb
[86]
[87]
pioneered the technique of nerve allografting with The study of Hong et al. examined all nerves of
[91]

encouraging results. Vascularized nerve allografts offer the upper limb. They identified the following nerves
several theoretical advantages: (1) they allow en bloc as suitable for microsurgical transfer, being of type A
reconstruction of nerve plexi; (2) they enhance the rate of or C: (1) the ulnar nerve in the upper arm and in the
nerve regeneration; and (3) they permit the use of larger forearm; (2) the median nerve in the upper arm and in
“trunk” grafts without central necrosis. [88] the forearm; (3) the segment of the anterior interosseous
Mackinnon et al. [89,90] described 7 cases of traumatic nerve distal to the flexor pollicis longus branch; (4) the
extremity injuries with massive peripheral nerve deficits upper lateral brachial nerve; (5) the lower lateral brachial
that could not be reconstructed by conventional nerve; (6) the superficial radial nerve; (7) the terminal
means. Four upper extremities and 3 lower extremities branch of the posterior interosseous nerve; and (8) a
were reconstructed. Nerve allografts were either used branch to the extensor indicis following the posterior
exclusively for the reconstruction (2/7) or in combination interosseous artery (when present). In normal clinical
with autografts (5/7). Total allograft lengths varied from situations, nerves 1 and 2 cannot be used because of
72 cm in a 3‑year‑old patient to 350 cm for a three‑nerve their functional importance. Harvest of nerve 3 results in
reconstruction in a 16‑year‑old patient. Initially, the loss of function of the pronator quadratus, which may be
allografts were harvested fresh and used immediately. In acceptable. This leaves nerves 4 through 8 as donor nerves
subsequent cases, the allografts were temporarily stored for vascularized nerve transfer, and potentially nerve 3 in
normal situations, with the superficial radial nerve being
Table 6: Indications for a lower limb nerve injury the longest with the most acceptable morbidity.
Vascularized sural nerve based on a pedicled superficial sural artery Lower limb
Vascularized sural nerve supplied by an arterialized lesser The study of Suami et al. examined all nerves of the
[81]
saphenous vein
lower limb. They identified the following nerves: (1) the
Plast Aesthet Res || Vol 2 || Issue 4 || Jul 15, 2015 191