Back to 2025 Abstracts
Establishing Baseline Median Nerve Cross-Sectional Area in Adolescents
Seth A Lowey, Medical Student
1; John R Fowler, MD
21Touro University California College of Osteopathic Medicine, Vallejo, CA; 2Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA
Introduction: The use of ultrasound for diagnosis of carpal tunnel syndrome (CTS) is expanding, yet there is a notable absence of baseline data regarding median nerve cross-sectional area (CSA) in adolescents. Adolescents and younger children may not tolerate nerve electrodiagnostic testing well, making ultrasound a reasonable alternative diagnostic test in this population. This study aimed to establish the baseline CSA of the median nerve at the carpal tunnel inlet using ultrasound in adolescents, providing foundational data for future diagnostic and clinical applications.
Materials & Methods: Ultrasound CSA of the median nerve was measured in a cohort of 35 adolescents (24 males, 11 females) without clinical signs and symptoms of CTS who were between 8 and 17 years of age. CSA (mm˛) was obtained by a hand fellowship-trained orthopedic surgeon just proximal to the level of the pisiform and inside the hyperechoic epineurium using the trace function. Participants were stratified into three age groups: 8-10 years (n=4 males, n=1 females), 11-13 years (n=6 males, n=6 females), and 14-17 years (n=14 males, n=4 females). Statistical analyses were performed to analyze age-related trends in median nerve dimensions.
Results: Median nerve CSA varied across age groups. In the youngest age group (8-10 years), males exhibited a mean CSA of 5.7 mm˛, while females had a mean of 6.0 mm˛. In the middle age group (11-13 years), males showed a mean CSA of 5.8 mm˛ and females a mean of 7.3 mm˛. In the oldest age group (14-17 years), males had a mean CSA of 8.9 mm˛ and females a mean of 7.1 mm˛.
Conclusion: This study aims to establish normative data for median nerve CSA in adolescents using ultrasound, filling a critical gap in current diagnostic practices for CTS. Females generally exhibited earlier maturation patterns in median nerve dimensions compared to males, as evidenced by the higher mean CSA observed in the 11-13 years age group. Based on this limited data set, it appears that by age 14, both male and female subjects had "adult-sized” median nerve CSA and that standard cut-off values would apply.
Back to 2025 Abstracts
