Nerve and Tendon Transfers After Cervical Spinal Cord Injury: A Systematic Review of Strength Outcomes in 959...

Tendon transfers and nerve transfers are two techniques available for reconstruction of elbow extension, grip, pinch, and release after spinal cord injury. This systematic review was aimed at assessing and comparing the strength outcomes of tendon and nerve transfers for functional reconstruction of the upper extremity to better guide surgical discussion.

This review was registered with PROSPERO ID: CRD42024595503 and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Embase, Scopus, and MEDLINE were queried for citations that presented strength outcomes for patients having undergone tendon and/or nerve transfers to restore upper-extremity function after a spinal cord injury. Weighted averages were used to report patient demographic data. A pooled estimate of strength outcomes was completed for the brachialis-to-anterior interosseous nerve transfer using a random-effects model.

Five hundred and ninety-four citations were screened for 51 included studies with a total of 959 patients who were, on average, 31.8 years old (range, 5-76). For elbow extension reconstruction, strength of M3 or greater was reported in 68% of patients who underwent nerve transfers, 79% of patients who underwent a biceps-to-triceps tendon transfer, and 70% of patients who underwent a deltoid-to-triceps transfer. The pooled proportion of patients achieving M3 or better strength after a brachialis-to-anterior interosseous nerve transfer was 0.5 (0.31-0.7), with better outcomes in younger patients. For the supinator-to-posterior interosseous nerve transfer, 78% of patients reported achieving M3 strength or better.

There is no gold standard for the functional reconstruction of the upper extremity after a spinal cord injury. The choice of procedure(s) remains patient-specific. Several options are available to surgeons treating tetraplegia, and patients have achieved considerable strength recovery from both nerve and tendon transfers. Current evidence demonstrates poor outcomes after brachialis-to-anterior interosseous nerve transfers. More homogeneous follow-up protocols are needed for strength measurement and patient-reported outcome measures for both nerve and tendon transfers.

Therapeutic III.