Do technical components of microanastomoses influence the functional outcome of free gracilis muscle transfer for elbow flexion in traumatic brachial plexus injury?

Abstract

Introduction: The traumatic lesions of the brachial plexus in adults are devastating injuries causing continuous severe functional impairment for both work and daily living activities. The restoration of elbow flexion is one of the most important movements for patient recovery to previous activities. Free gracilis muscle transfer has good outcomes for cases with late presentation or as a rescue surgery to regain elbow flexion, however, bad results are present in all cohorts with insufficient recovery of muscle strength for elbow flexion. A number of hypotheses can be postulate to explain the fair results observed in some cases of free gracilis muscle transfer for elbow flexion. Most studies in the current literature compare the choice of the donor nerve used in neurotization and nerve grafts. The aim of this study is to evaluate if technical components of microvascular anastomosis could influence the functional outcome of free functional muscle transfer for elbow flexion in adult patients with traumatic brachial plexus injury.

Material and methods: Included all adult patients with traumatic brachial plexus injury submitted to free functional gracilis muscle transfer for elbow flexion. The complications and functional results according to British Medical Research Council (BMRC) score were recorded.

Results: We assessed 26 patients with mean age of 32.8 years. The most common donor nerve for gracilis muscle was the accessory nerve in 18 patients. Eighteen patients presented with good result (M3/M4). The mean ischemia time was higher for patients with bad results (132 minutes) comparing with patients with good results (122 minutes). Patients with only one venous anastomosis had 41% of poor functional outcome compared with 22% of cases with two venous anastomoses. No statistically significant difference in the ischemia time of the cases with good or poor functional outcome was observed (p=0.657), as for the number of venous anastomoses (p=0.418).

Conclusion: Our study observes that patients with only one venous anastomoses for drainage of free gracilis and those with longer intraoperative ischemia time had higher incidence of poor functional outcome of free gracilis muscle transfer for elbow flexion, but not statistically significant.

Level of proof: II; prospective cross-sectional study.

Keywords: Brachial plexus; Elbow flexion; Gracilis transfer.