Abstract
In combined high median and ulnar nerve injury, transfer of extensor digiti minimi (EDM) and extensor carpi ulnaris (ECU) nerve branches to restore intrinsic hand function is previously described. A segment of nerve graft is required in this operation. The aim of this study was to evaluate the feasibility of using the sensory branch of radial nerve (SRN) as an “in situ vascular nerve bridge'” (IVNB) instead of sural nerve graft.
Twenty fresh cadavers were dissected. In proximal forearm incision, the feasibility of transferring the EDM/ECU branches to the distal stump of transected SRN was evaluated. In distal forearm incision, the two distal branches of the SRN were transected near the radial styloid process to determine whether transfer of the proximal stumps of these branches to the motor branches of the median (MMN) and ulnar (MUN) nerves is possible. The number of axons in each nerve was determined.
The size of the dissected nerves and their location demonstrate that tension free nerve coaptation is easily possible in both proximal and distal incisions.
Utilisation of the SRN as an IVNB instead of the conventional sural nerve graft has some advantages. Firstly, the sural nerve graft is a single branch and could be sutured to either the MMN or MUN, whereas the SRN has two terminal branches and can address both of them. Secondly, the IVNB has live Schwann cells and may accelerate the regeneration. Finally, this IVNB does not require leg incision and could be performed under regional anesthesia. The SRN as an IVNB is a viable option which can be used instead of conventional nerve graft in some brachial plexus or high median and ulnar nerve injuries when restoration of intrinsic hand function by transfer of EDM/ECU branches is attempted.
