Ultrasonographic measurement of the cross-sectional area of the axillary nerve

Abstract

Introduction The objectives of this study were to determine normal reference values for ultrasonographic measurement of the cross-sectional area (CSA) of the axillary nerve and to standardize the measurement methods. Methods Sixty healthy volunteers were evaluated. Ultrasonography was performed with the shoulder positioned in 100 degrees-120 degrees abduction and 90 degrees external rotation. The CSA of the axillary nerve was measured bilaterally. Results The normal CSA of the right axillary nerve was 2.9 +/- 1.1 mm(2). The side-to-side discrepancy was 22.8% +/- 17.8%. Discussion These reference values may be helpful for investigating pathologies involving the axillary nerve.