Predictive factors for distal suprascapular nerve injury in brachial plexus injury: A retrospective cohort study.

Abstract

The spinal accessory nerve (SAN) to suprasapular nerve (SSN) transfer is performed to improve shoulder function after brachial plexus injury (BPI) involving C5-6 nerve roots. Unrecognized SSN injury may contribute to reconstruction failure. This study aimed to assess the incidence of distal SSN injury and the associated factors in adults with BPI undergoing SAN to SSN transfer. This retrospective cohort study included adults with BPI with planned SAN to SSN transfer. Charts were reviewed to collect demographic, injury, and surgical data. Descriptive statistics summarized the study population, and univariate analyzes examined factors associated with distal SSN injury. There were 41 patients with a planned SAN to SSN transfer (median age 31.0 years; 40 were male). The most common mechanisms of injury were ATV, motorcycle, or snowmobile accidents (30 patients), 13 patients had complete BPI and associated shoulder injuries were present in 21 patients. SAN to SSN transfer was completed in 20 patients and abandoned in 21 patients, due to distal SSN injury (11 patients), functional SSN on intraoperative stimulation (8 patients), or non-functioning donor SAN (2 patients). Distal SSN injury was significantly associated with increased age (p=0.03) and the presence of an associated shoulder injury (p=0.02), but not significant with type of BPI or mechanism of injury. Distal SSN injury was common and frequently led to abandonment of SAN to SSN transfers. A posterior surgical approach is recommended, particularly in patients with associated shoulder injuries, to allow for thorough assessment of distal SSN injury.