Page 348 - Read Online

Costa et al. Plast Aesthet Res 2020;7:32 I http://dx.doi.org/10.20517/2347-9264.2020.43 Page 5 of 12
[31]
Koriem et al. directed a prospective study in 21 patients with a high ulnar nerve injury. In 10 patients,
the lesion was managed through direct and isolated repair of the ulnar nerve (UR) while in the remaining
11 patients, the repair was associated with a supercharged end to side (SETS) nerve transfer. In the latter
group, the patients showed improvement at six months’ follow-up, which is a shorter time than necessary
to regenerate ulnar nerve fibers from the lesion.

[32]
In 2010, Sherif and Amr demonstrated that a double bridging nerve graft between the motor components
of the ulnar and median nerve in the distal forearm could prevent atrophy of the intrinsic muscle until
proximal nerve regeneration can arrive at these effectors.

These authors reported the best results in median nerve effector protection, and a good result regarding
the ulnar nerve with the creation of an artificial Martin-Gruber connection through a double end-to-side
[33]
bridge graft. In the same way, Colonna et al. reported a double end-to-side coaptation via a nerve graft
enabled fibers from the donor median nerve to regenerate the injured ulnar nerve

Anterior interosseous nerve to ulnar motor branch transfer technique
A lazy S incision at the level of Guyon’s canal and dissection of the pronator quadratus muscle allows
exposure of the ulnar and median nerves at the level of the distal forearm. At the level of Guyon’s canal,
it is possible to identify sensory and motor branches of the ulnar nerve; internal neurolysis of the motor
fibers of the ulnar nerve proceeds as proximally as possible and finally these are divided. The anterior
interosseous nerve is followed as it enters the pronator quadratus muscle and divided as distally as possible.
The proximal stump of the anterior interosseous nerve is then coapted end-to-end to the distal stump of
the motor branch of the previously dissected ulnar nerve.

Motor nerve transfer in the distal palm
[34]
Barbour et al. reported transfers from the branch of the posterior interosseous nerve (specifically,
branches from the extensor digiti minimi and extensor carpi ulnaris) with sub-optimal results.

This demonstrates the inconsistent pattern of reinnervation seen when reinnervating numerous motor
functions with an inadequate number of donor nerves.

The TBMN has been used in recent years as a fiber donor in the palm to restore function of the deep motor
[35]
branch of the ulnar nerve. Aszmann and Gesselbauer built on Riche-Cannieu’s ulnar-to-median nerve
communication in the palm and proposed a distal babysitting technique via a nerve graft between the
thenar branch of the median nerve (donor) and the ulnar nerve “just distal to Guyon’s canal”. At long-term
follow-up at 6 years, they presented very promising results with intrinsic motor function after distal ulnar
lesions in three patients.

[36]
In 2017, Colonna et al. suggested using the branch for the first lumbrical as a babysitter for the deep
motor branch of the ulnar nerve to avoid intrinsic atrophy. This hypothesis was based on anatomical
studies and qualitative and quantitative analysis of nerve fibers.
In 2018, Bertelli et al. described nerve transfer from the motor branch of the opponens pollicis (OPB) to
[37]
the deep branch of the ulnar nerve in the terminal division (TDDBUN) to increase pinch strength. With
promising results, they suggested combining transfers from the OPB to the TDDBUN and distal AIN to the
motor branch of the ulnar nerve for reconstruction.

Median nerve
In sensory nerve transfers for the median nerve, the fundamental aim is to restore sensitivity of the thumb
[38]
and index finger to ensure pinch and grip functions, which are essential for fine motor tasks .