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Costa et al. Plast Aesthet Res 2020;7:32 I http://dx.doi.org/10.20517/2347-9264.2020.43 Page 7 of 12

Figure 6. Transfer of sensation with transposition of fascicles for the third to the first web space. Yellow: functional nerves; lighter
yellow: sensitive areas; pink: nonfunctional nerves; lighter pink: non sensitive areas

[44]
In incomplete lesions of the median nerve or high lesions of the brachial plexus (C5-C6) , the sensory
component for the third interdigital space can be preserved since it originates from a distinct fascicle. This
fascicle can be dissected up to the distal forearm and coapted to the distal portion of the fascicle for the
first web space in order to restore critical sensitivity between the thumb and index finger [Figure 6]. It is
possible to access both the recipient and donor nerves nearby through a single incision. This technique also
avoids performing a sensory nerve transfer in the hand, thereby avoiding scarring on the palmar surface of
[45]
the hand itself. In addition, the repair is quick and easy to achieve . The distal stumps of the donor fascicle
are also coapted end-to-side to the functional fascicles to maintain protective sensation in the donor site.

Fourth web space digital nerve to first web space digital nerve transfer: technique
A classic incision is made over the carpal tunnel and extended to the first and fourth web spaces with
zigzag Bruner-Type incisions. Under the superficial arterial arch, the branches of the median and ulnar
nerves are identified. The branch to the fourth web space is followed and divided as distally as possible,
which corresponds to the heads of the metacarpals. The nerve to the first web space is dissected proximally
in order to achieve a length that allows tensionless coaptation. When an adequate length is obtained, the
median-dependent branch is cut proximally and transferred to the proximal stump of the fourth digital
nerve, which is dependent on the ulnar nerve. All other remaining sensory nerves are coapted end-to-side,
as in Figure 4, to restore protective sensation.

Very distal sensory nerve transfers in high median nerve lesions: technique
The surgeon makes a V incision on the radial side of the metacarpophalangeal joint of the second finger.
This incision exposes the dorsal sensory branch of the radial nerve and the radial collateral of the digital
nerve of the second finger from the median nerve. These are divided in such a way that the proximal stump
of the dorsal sensory branch for the second finger can be sutured end-to-end to the distal stump of the
radial collateral of the proper digital nerve. Another V-shaped skin incision is performed, centered on the
ulnar side of the metacarpophalangeal joint of the first finger, and the dorsal sensory branch and the digital
collateral nerve are identified. These are subsequently divided and coapted as previously described for the
second finger.

Radial nerve
The sensibility of the dorsum of the hand can be re-established via the lateral antebrachial cutaneous nerve
(LACN) due to its characteristics. The LACN runs near the sensory radial branch of the distal forearm. Its
dimensions are suitable for end-to-end coaptation, which can restore a large area of sensation to the back
of the hand, by sacrificing a critical distal distribution. The LACN is also expendable and its use does not
create significant morbidity along its supplied territory .
[4]