Selective motor fascicle transfer and neural-machine interface: case report

Abstract

An amputated nerve transferred to a nearby muscle produces a transcutaneously detectable electromyographic signal corresponding to the transferred nerve; this technique is known as targeted muscle reinnervation (TMR). There are 2 issues to overcome to improve this technique: the caliber and the selectivity of the transferred nerve. It is optimal to select and transfer each motor fascicle to achieve highly developed myoelectric arms with multiple degrees-of-freedom motion. The authors report on a case in which they first identified the remnant stumps of the amputated median and radial nerves and then identified the sensory fascicles using somatosensory evoked potentials. Each median nerve fascicle was transferred to the long head branch of the biceps or the brachialis branch, while the short head branch of the biceps was retained for elbow flexion. Each radial nerve fascicle was transferred to the medial or lateral head branch of the triceps, while the long head branch of the triceps was retained for elbow extension. Electrophysiological and functional tests were conducted in the reinnervated muscles. Functional and electrophysiological improvement was noted, with marked improvement in the identification rate for each digit, forearm, and elbow motion after the selective nerve transfers. The authors note that more selective nerve transfers may be required for the development of prostheses with multiple degrees of freedom.

Pain and Functional Outcomes Following Targeted Muscle Re-innervation: A Systematic Review

“…Outcome measures were divided into pain, functional, and electrical measures, and definitions are presented in Table 1. 1–83…”

Expanding the top rungs of the extremity reconstructive ladder: targeted muscle reinnervation, osseointegration, and vascularized composite allotransplantation

“…OI prostheses stand to stabilize the patient-prosthetic interface, thereby limiting movement at surface electrodes for more reliable EMG directed prosthetic movement [29] . Individual fascicular transfer may allow even greater prosthetic control through the creation of an array of individual EMG signals [30] . Finally, while all currently available prostheses rely on visual feedback, future prostheses will integrate a sensory feedback loop to allow more effective patient interaction with their environment [21] .…”

Safe level for harvesting for ulnar and median nerve transfers: a microanatomical and histological study

“…To reconstruct hand function, nerve transfer was used to restore intrinsic muscle function in the hand (Mackinnon, 2016). Furthermore, selective nerve transfers can be used in targeted muscle reinnervation to control prostheses (Takagi et al., 2019).…”