Medial subtalar dislocation from a low-energy trauma. A case report and review of the literature

INTRODUCTION: Subtalar dislocation is a rare injury characterized by a simultaneous dislocation of the talocalcaneal and talonavicular joints. The most common type is caused by high-energy trauma with medial dislocation of the foot. This injury is frequently associated with fractures, but isolated dislocations are also reported. CASE PRESENTATION: We report a rare case of medial subtalar dislocation secondary to low-energy injury in a 61-year-old woman. Following X-rays and CT scan, prompt closed reduction was performed under sedation and, after reduction, X-rays showed a good realignment of the foot. The CT scan revealed an occult non-displaced fracture of the posterior part of the talus. The patient was managed conservatively by a non-weight bearing cast for four weeks, followed by a rehabilitation program. At follow-up, six months later, we observed a good clinical and radiographic result. DISCUSSION: The reported case confirms that the mechanism of injury is an important factor in predicting the final result, since subtalar dislocations secondary to a high-energy trauma are often associated with significant complications. We believe, in agreement with other authors, that a low-energy trauma generally doesn't produce long-term morbidity. Prompt reduction is very important in order to minimize soft tissue and neurovascular complications, although a CT is recommended to identify occult fractures. CONCLUSION: Subtalar dislocations, caused by low energy trauma, if adequately reduced in the emergency room, generally heal with conservative treatment, reducing the risk of significant complications. However, since we report a single patient, further case analysis is needed to make solid conclusions.