Isolated Fourth Carpometacarpal Joint Injury in High-Level Baseball Players: A Case Series

• Published in: Hand (New York, N.Y.) N.Y.), 2024-11, Vol.19 (8), p.1230-1234
• Main Authors: Stults, William P., Lourie, Gary M., Royal, Jeremy T.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Anti-Inflammatory Agents, Non-Steroidal - therapeutic use; Athletic Injuries - diagnostic imaging; Athletic Injuries - therapy; Baseball - injuries; Carpometacarpal Joints - diagnostic imaging; Carpometacarpal Joints - injuries; Conservative Treatment; Humans; Magnetic Resonance Imaging; Male; Rest; Return to Sport; Splints; Synovitis - diagnostic imaging; Synovitis - etiology; Young Adult
• ISSN: 1558-9447; 1558-9455; 1558-9455
• DOI: 10.1177/15589447231167584

Background: We present a case series of high-level baseball players having sustained a rare, isolated injury to the fourth carpometacarpal joint of the nondominant or bottom hand during a jammed swing. Methods: Ten patients were evaluated for ulnar-sided wrist pain and were subsequently diagnosed with fourth carpometacarpal joint synovitis based on physical examination and magnetic resonance imaging revealing increased signal intensity within the joint. Results: Conservative treatment modalities including rest, nonsteroidal anti-inflammatory medications, splinting, and corticosteroid injections resulted in return to play within 4 weeks for all patients. Conclusions: We propose a mechanism of injury involving the bottom hand in relative pronation receiving a dorsally directed force from bat during a jammed swing resulting in isolated injury to the fourth carpometacarpal joint. This report serves to highlight this rare injury in high-level baseball players and recommend a treatment algorithm for early return to play.