Science News: Ultrasonographic Prevalence of Ulnar Nerve Displacement at the Elbow in Young Baseball Players

Submitted by: Oksana Sayko, MD
Edited by: Nakul Katyal, MD

Kawabata M, Miyata T, Tatsuki H, et al. Ultrasonographic prevalence of ulnar nerve displacement at the elbow in young baseball players. PM R. 2022;14(8):955-962. doi:10.1002/pmrj.12658

Summary: Studies regarding ulnar nerve damage/displacement have been performed primarily in adults. The authors of this study assessed the ulnar nerve displacement in young baseball players.

The prevalence and related factors associated with ulnar nerve displacement at the elbow were examined in 57 athletes aged 10-12. Ultrasonography findings of ulnar nerve dynamics at the cubital tunnel were analyzed in a total of 114 elbows. Elbows were grouped into non-dislocation and displacement (sub-luxation or dislocation) groups according to ultrasound findings.
 
Thirty-six (31.6%) elbows demonstrated sonographic findings of ulnar nerve displacement, with 13 (11.4%) subluxations and 23 (20.2%) dislocations. Fourteen (24.6%) participants experienced nerve displacement in the dominant elbow only, whereas nerve displacement in both elbows occurred in 11 (19.3%) participants. Nerve displacement in the nondominant elbow only was not observed. Hand dominance and tenderness of the arcade of Struthersʼ were factors associated with ulnar nerve displacement.
 
One-third of the young baseball players evaluated had ultrasonographic findings compatible with ulnar nerve displacement at the elbow. Hand dominance and tenderness of Struthers arcade were the only factors associated with ulnar nerve displacement.

Comments: Ultrasound may help identify patients with ulnar nerve displacement and contribute to the understanding of its pathophysiology in young baseball players.