Pure posteromedial tibiotalar dislocation in an adolescent student: a case report and literature review

Pure Posteromedial tibiotalar dislocation unaccompanied by fractures represents an exceptionally rare orthopedic injury, accounting for approximately 0.065% of ankle injuries and 0.46% of ankle dislocations. Such injuries typically result from high-energy trauma, with limited reports involving low-energy mechanisms in athletic activities. This case illustrates the successful management of a closed posterior ankle dislocation in a young student, emphasizing the importance of prompt intervention and structured rehabilitation. A 17-year-old male student sustained a pure posterior tibiotalar dislocation during a recreational basketball game, following a forced inversion and plantarflexion mechanism. Immediate closed reduction was performed under local anesthesia combined with intravenous analgesia, followed by immobilization in a splint and subsequent transition to a controlled ankle motion (CAM) boot. Post-reduction CT confirmed anatomical reduction and excluded occult fracture, while CTA showed no evidence of vascular injury; serial clinical examinations revealed no sensory or motor deficit. At one-year follow-up, the patient achieved a full functional recovery and unrestricted return to academic and physical activities. This case underscores that early closed reduction and phased rehabilitation can yield excellent outcomes in pure posteromedial tibiotalar dislocation, even in adolescent populations. The report highlights the viability of non-operative management for such injuries and contributes to the sparse literature on low-energy mechanisms in young, non-professional athletes.