[Rare case of palmar disc dislocation after wrist distorsion].

OBJECTIVE: The aim of this study was the elaboration of clinical symptoms and image findings in injuries of the wrist and ulnar-sided pain with accompanying damage to the articular disc and the triangular fibrocartilage complex (TFCC).

MATERIAL AND METHODS: This article reports about a 26-year-old male patient who presented to the department of surgery of this hospital after repeated falls onto the right wrist. Following the latest fall there was persistent wrist pain and limited movement, especially in supination. The physical examination showed pressure pain above the ulnocarpal complex; however, under forced pronation and supination no pain in the ulnocarpal complex could be triggered.

RESULTS: Due to the symptoms damage to the TFCC was suspected and a magnetic resonance imaging (MRI) examination of the wrist was carried out. A TFCC damage reaching as far as the dorsal radioulnar ligament involving the dorsal suspension was demarcated with dislocation and displacement of the disc. For further differentiation of the damaged structures arthrography was performed and contrast medium containing gadolinium was injected into the joint gap. The imaging showed avulsion of the dorsal triangular disc from the dorsal suspension with volar dislocation. Treatment was continued with an arthrotomy by the formation of an ulnar pedicled capsular flap, the luxated TFCC was repositioned, central frayed and torn parts were resected and smoothed. Finally, the TFCC was refixed with two 3/0 PDS U‑sutures.

CONCLUSION: Ulnar-sided wrist pain can be caused by a variety of clinical pathologies, so that often no diagnosis can be made based on clinical symptoms alone and an imaging method is required; however, for a clear assessment of the ligament or joint injuries an MRI is necessary. Particularly for the evaluation of the TFCC injuries MRI is a sensitive diagnostic method. In the decision making, especially when atypical injury patterns are present, an arthrography should be performed in addition to MRI to obtain the best possible information on the anatomical circumstances.

KEY POINTS: In cases of injuries of the wrist and ulnar-sided pain collateral damage to the articular disc and the TFCC should always be considered and excluded when appropriate. A dislocation of the disc at the wrist is a rare consequence of trauma but should be considered in the differential diagnosis. In cases of unclear MRI results and complex injuries of the wrist or unclear symptoms, MR arthrography can be helpful.