RESUMO
CASE: A 62-year-old male patient suffered an irreducible posterolateral knee dislocation after a horse fell on him. The left knee was slightly flexed with a medial dimple sign present. The medial retinaculum, medial patellofemoral ligament, posteromedial corner structures, and vastus medialis obliquus (VMO) muscle were incarcerated in the medial joint. An open reduction and the medial retinaculum and VMO gap were repaired, and the knee was stabilized in an external fixator for 4 weeks. At 32-month follow-up, the patient had almost full knee motion and good subjective outcomes with moderate residual joint laxity. CONCLUSION: Early clinical diagnosis of irreducible knee dislocations and emergent open reduction should be performed to reduce the risk of soft-tissue compromise.