The authors report the case of a 21-year-old woman who sustained a femoral avulsion of the popliteus tendon in a motor vehicle accident. The posterolateral injury was suspected on physical examination and confirmed by magnetic resonance imaging and arthroscopic examination. The popliteus tendon was repaired using two suture anchors. Mild clinical instability was present initially and resolved postoperatively. No residual pain, weakness, or posterolateral instability was noted.