Evaluation of axillary nerve integrity and shoulder functions in patients who underwent lateral deltoid splitting approach

Abstract

Aim: The most common complication of the Lateral deltoid splitting approach (LDSA), which is used in the shoulder area, especially for posterior extension fractures and other soft tissue pathologies, is axillary nerve injury. Determining the frequency of nerve injuries that may occur after LDSA is decisive for the applicability of this approach. Therefore, in our study, we aimed to evaluate the axillary nerve integrity and shoulder functions in patients who underwent LDSA. Methods: In this prospective cohort study, 55 patients who were operated with LDSA for proximal humerus fractures between February 2015 and July 2018 were evaluated. Among these patients, 35 were selected and included in the study. Six months later Electrophysiological tests (Electroneuromyelography -ENMG) and Constant Shoulder Score (CSS) were used for evaluation of each operated and non-operated shoulder. CSS difference between the operated and non-operated sides was graded as mild (11-20 point), moderate (21-30) and severe (>30). Results: Mean age of the group was 66 (9) years. Twenty-five patients were female and 10 were male. Mean follow-up time was 4 (1) years. Mean latencies of axillary nerve were 4.6 (1.8) msn, 3.7 (0.54) msn and mean amplitudes of axillary nerve were 6.6 (2.21) mV, 8.4 (2.80) mV in the operated and non-operated shoulders, respectively. There was no statically significant difference between the operated and non-operated sides according to latency and amplitude (latency P=0.25, amplitude P=0.16). Mean CSS of the patients were 28.7. CSS of 12 patients were severe (mean: 39.08), 18 patients, moderate (mean 25.4) and 5 patients, mild (mean 16). There was no statically significant correlation between CSS and axillary nerve latency / amplitude (P= 0.62, r=0.267 / P=0.98, r=-0.339). Fracture type and CSS showed a statically significant correlation (P=0.032, r=0.829). Conclusion: This study revealed that LDSA provides wide and versatile fracture control without compromising the deltoid muscle functions and axillary nerve, especially in fractures extending to the posterior part of the proximal humerus.