Trilogy of isolated deep medial collateral ligament injuries of the knee: A set of three cases and overview of the literature.

The authors present three unique cases of isolated deep medial collateral ligament (dMCL) injuries and comprehensively review the current literature. An isolated dMCL injury is often overlooked in clinical practice, and a consensus on the most adequate treatment is needed. Three male patients were examined at our institution directly following the trauma. The first patient experienced isolated soft-tissue avulsion of the dMCL, the second patient had a bony avulsion from the femoral insertion of the dMCL, and the third patient presented with an isolated "reverse Segond" fracture, which has not previously been described in the literature. All three injuries resulted from a violent external knee joint rotation. The treatment regime included a knee brace for up to 5 weeks and a physical therapy regimen for up to 3 months. All three patients reported satisfactory outcomes regarding restored knee function, absence of symptoms, and early return to activities at the final follow-up. STUDY DESIGN: Case report. LEVEL OF EVIDENCE: IV.