Tendon Transfer versus Nerve Transfer for the Reconstruction of Key Pinch and Grip Strength in Isolated High Traumatic Injuries of the Ulnar Nerve: A Systematic Review

Abstract

Background: Primary repair for traumatic injuries to the ulnar nerve alone does not always restore satisfactory hand function, particularly in injuries above the elbow where the long distances for regeneration limit motor reinnervation. Reductions in key pinch and grip strength are some of the main complaints. Tendon transfers have traditionally been used to improve key pinch and grip strength as a late salvage where primary nerve regeneration has run its course. Nerve transfers have been proposed as an alternative procedure and may be offered early to augment recovery, lengthen the window for reinnervation or provide motor reinnervation where the results of nerve repair are expected to be poor. This review sought to identify whether one type of procedure was superior to the other for reconstructing key pinch and grip strength.Methods: Medline, Embase and Cochrane Library were searched to identify articles that concerned nerve or tendon transfer following isolated traumatic injury to the ulnar nerve. Articles were excluded if patients had polytrauma or degenerative diseases of the peripheral nerves.Results: A total of 179 articles were screened for inclusion. And 35 full-text articles were read and assessed for eligibility, of which seven articles were eligible. Following citation search, two additional articles were included. Five tendon transfer articles and four nerve transfer articles were included. Key pinch and grip strength outcomes for both procedures were roughly similar, though tendon transfers carried a much higher risk of complications.Conclusions: Based on the key pinch and grip strength outcomes, tendon transfer and nerve transfer restore a similar degree of function following traumatic ulnar injury. Reported nerve transfer outcomes for grip strength were slightly better. Return to useful function was faster following tendon transfers. Preoperative data and more patient-reported outcome measures should be recorded in future studies to provide more context for each procedure type.Level of Evidence: Level III (Therapeutic)