Isolated sciatic nerve entrapment by ectopic bone after femoral head fracture-dislocation.

Although posttraumatic pelvic heterotopic ossification (HO) after hip fracture dislocation is well established, and nerve encasement by HO may occur, the development of neurologic deficit is rare. A thorough history and adequate clinical suspicion are imperative in the workup of affected patients. Computed tomography and magnetic resonance imaging provide good visualization and assist in surgical planning. If symptoms persist and are recalcitrant to conservative management, surgical intervention with HO excision and nerve neurolysis can be performed with success.