Case ReportsAnomalous Flexor Digitorum Profundus Muscle Bellies as a Cause of Snapping Wrist and Carpal Tunnel Syndrome A Case ReportFalcon, Spencer MD1; Everist, Brian MD2; Brubacher, Jacob MD1,a Author Information 1Department of Orthopaedic Surgery, University of Kansas Medical Center, Kansas City, Kansas 2Department of Radiology, University of Kansas Medical Center, Kansas City, Kansas aE-mail address for J. Brubacher:[email protected] Investigation performed at the University of Kansas Medical Center, Kansas City, KS Disclosure:TheDisclosure of Potential Conflicts of Interestforms are provided with the online version of the article (https://links.lww.com/JBJSCC/B688). JBJS Case Connector: October-December 2021 - Volume 11 - Issue 4 - e21.00311 doi: 10.2106/JBJS.CC.21.00311 Buy Associated Video Metrics Abstract Case: A 20-year-old right hand dominant woman presented with an audible and painful snapping wrist occurring with finger flexion. This bothersome mechanical finding and concomitant carpal tunnel syndrome (CTS) did not resolve with conservative measures. Dynamic magnetic resonance imaging revealed anomalous flexor digitorum profundus (FDP) muscle bellies as the cause of the mechanical snapping and irritation of the median nerve. Carpal tunnel release and excision of anomalous muscle within the carpal tunnel and distal forearm provided complete resolution of symptoms. Conclusion: Anomalous muscle bellies of the FDP is a rare cause of a volar snapping wrist and CTS. Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated
