Supinator to Posterior Interosseous Nerve Transfer for Restoration of Finger Extension

Abstract

BACKGROUND Cervical spinal cord injuries result in a severe loss of function and independence. The primary goal for these patients is the restoration of hand function. Nerve transfers have recently become a powerful intervention to restore the ability to grasp and release objects. The supinator muscle, although a suboptimal tendon transfer donor, serves as an ideal distal nerve donor for reconstructive strategies of the hand. This transfer is also applicable to lower brachial plexus injuries. OBJECTIVE To describe the supinator to posterior interosseous nerve transfer with the goal of restoring finger extension following spinal cord or lower brachial plexus injury. METHODS Nerve branches to the supinator muscle are transferred to the posterior interosseous nerve supplying the finger extensor muscles in the forearm. RESULTS The supinator to posterior interosseous nerve transfer is effective in restoring finger extension following spinal cord or lower brachial plexus injury. CONCLUSION This procedure represents an optimal nerve transfer as the donor nerve is adjacent to the target nerve and its associated muscles. The supinator muscle is innervated by the C5-6 nerve roots and is often available in cases of cervical SCI and injuries of the lower brachial plexus. Additionally, supination function is retained by supination action of the biceps muscle.

Distal median and radial nerve branch transfer techniques for upper extremity reanimation

“…All patients met at least MRC grade 3, with 3/4 patients recovering MRC grade 4 function of the FPL and FDP [21] . Hawasli et al reported a detailed case of a patient who received a brachialis to AIN transfer after a complete C7 spinal cord injury [18] . At 3 months postoperatively, the patient demonstrated early reinnervation, regaining MRC grade 3 strength in the FDP and FPL of the left hand [18] .…”

“…Hawasli et al reported a detailed case of a patient who received a brachialis to AIN transfer after a complete C7 spinal cord injury [18] . At 3 months postoperatively, the patient demonstrated early reinnervation, regaining MRC grade 3 strength in the FDP and FPL of the left hand [18] . One of the most recent case series for this technique was described by Souza et al in 2020, where 11 patients had lower brachial plexus injuries and received brachialis to AIN transfers in addition to supinator to PIN transfers [22] .…”

“…Nerve transfers should be tailored to the requirements of the patient to potentially achieve the best possible outcome. While physical examination remains the most important method for determining the candidacy of donor nerves, imaging techniques such as magnetic resonance imaging may have a role in decision making [18] .…”

“…Following confirmation of the brachialis nerve with stimulation demonstrating brachialis muscle contraction, the brachialis nerve is dissected distally to decrease tension during the repair. The brachialis and AIN can then be coapted end-to-end using microsurgical techniques [18] .…”

Distal nerve transfer (PT-AIN, SUP-PIN) for regaining hand function in C8, T1 root injury following extirpation of the right C8, T1 schwannoma

“…Distal nerve transfer (pronator teres-anterior interosseus nerve, supinator-posterior interosseus nerve) 1,2 for regaining hand function in C8, T1 root injury following extirpation of the right C8, T1 schwannoma. 0:35 Indications for Distal Nerve Transfer.…”