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Updated: Jul 18, 2026

Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies
Published on: January 11, 2019
Anomalous Flexor Digitorum Profundus Muscle Bellies as a Cause of Snapping Wrist and Carpal Tunnel Syndrome: A Case
Spencer Falcon1, Brian Everist2, Jacob Brubacher1
1Department of Orthopaedic Surgery, University of Kansas Medical Center, Kansas City, Kansas.
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.
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