Cross-sectional area in median and ulnar nerve ultrasound correlates with hand volume.

BACKGROUND: The influence of demographic and anthropometric factors on nerve cross-sectional area (CSA) reference values in high-resolution ultrasound was evaluated in a prospective observational study. METHODS: We measured CSA of median, ulnar, radial, and sural nerves in 80 healthy adults from 18 to 98 years of age. Pearson's correlation and multiple linear regression with age, gender, body mass index, and hand volume were calculated. RESULTS: Ulnar and median nerve CSA showed a significant positive correlation with ipsilateral hand volume. Median nerve CSA in the left forearm (mean, 6.2 mm2 ; SD, 1.2) increased by 0.006 mm2 (SE = 0.002; P < .001) per cm3 of hand volume, resulting in a difference of 1.9 mm2 predictable by hand volume (mean, 326 cm3 ; SD, 81; range, 180-500). CONCLUSIONS: The observed correlation of CSA and hand volume may influence the interpretation of CSA values in patients with very large or small hands.