Arthroscopic resection of a lateral bipartite talus with anterior talofibular ligament capsuloligamentous repair: a rare case report.

BACKGROUND

Bipartite talus (talus bipartitus) is a rare anatomical variant characterized by separation of the talus into two fragments. Most reported cases involve the posterior talar process, whereas a lateral bipartite talus is exceptionally uncommon.

CASE PRESENTATION: A 42-year-old man presented with chronic lateral ankle pain and a palpable bony prominence. Radiographs and computed tomography demonstrated a well-corticated fragment separated from the talar body, consistent with a bipartite talus. Arthroscopic excision of the fragment was performed. Intraoperatively, the anterior talofibular ligament (ATFL) was found to be attached to the fragment; therefore, arthroscopic Broström capsuloligamentous repair using an all-suture anchor was subsequently performed to restore lateral ankle stability. At the 18-month follow-up, the patient demonstrated marked symptomatic improvement with restoration of daily activities, improved functional scores, and no evidence of residual fragment or postoperative instability.

DISCUSSION: A bipartite talus may mimic a fracture nonunion or an accessory ossicle, making advanced imaging important for diagnosis. In this case, the fragment was located laterally, with involvement of the ATFL footprint. Arthroscopy enabled minimally invasive fragment excision and simultaneous ligament repair.

CONCLUSION

Lateral bipartite talus is an exceptionally rare condition that may mimic other fracture-related conditions and compromise lateral ankle stability because of the ATFL attachment. Arthroscopic fragment excision combined with ATFL capsuloligamentous repair was a feasible, minimally invasive treatment with favorable clinical outcomes.