Recurrent total knee arthroplasty dislocation after dorsal meningioma diagnosed.

We report on a 68-year-old woman with gonarthrosis who underwent total knee arthroplasty. Having initially achieved a satisfactory result, she developed at 5 months postoperation an irreducible flexion contracture necessitating revision surgery; but no pathological findings were discovered. In the immediate postoperative period, the patient developed a severe spasm of the hamstring muscles and a paralysis of the external popliteal sciatic nerve with a posterior dislocation of the knee. After reduction, an electromyography study showed an alteration in medullary sensitive conduction; and the magnetic resonance image showed a lesion compatible with meningioma. This complication has not been previously described as a consequence of spinal tumor. Technical considerations are described for this rare complication, which remains a serious challenge for the orthopedic surgeon.