Posterior interosseous nerve palsy caused by synovial chondromatosis arising in the annular periradial recesses of the elbow

We present a rare case report of a patient who presented with posterior interosseous nerve palsy caused by synovial chondromatosis. Synovial chondromatosis arising in the annular periradial recesses of the elbow joint was detected, and the mass developed two major portions constricted with the annular ligament. After surgical resection, posterior interosseous nerve palsy fully recovered and there was no recurrence of the lesion of synovial chondromatosis.