Surgical outcome for intra- and extrapelvic femoral nerve lesions

Seventy-eight traumatic neuropathies were seen in 94 patients with femoral nerve lesions; 54 of these were operated on because of persistent complete functional loss and/or pain. The most common mechanism of injury to the femoral nerve was iatrogenic due to inguinal herniorrhaphy, total hip replacement, intraabdominal vascular or gynecological operation, and, less commonly, appendectomy, lumbar sympathectomy, and laparoscopic procedures. Femoral nerve injuries also resulted from penetrating gunshot and stab wounds, laceration by glass, and stretch/contusive injuries associated with pelvic fractures. There were no signs of clinical or electrical recovery in 45 of 78 patients with traumatic nerve injuries. These and other partial injuries associated with pain were explored and evaluated by intraoperative nerve stimulation and recording of nerve action potentials (NAPs). Despite complete loss of nerve function preoperatively, 13 patients had recordable NAPs and underwent neurolysis; each recovered function to at least a Grade 3 level. Twenty-seven patients had sural graft repairs performed with graft lengths varying from 2.5 to 14 cm. Most patients had some nerve regeneration and regained function to Grade 3 to 4 levels by 2 years postoperatively. Four of five patients with suture repairs recovered to Grade 3 or better within 2 years postoperatively. Despite a proximal pelvic level for most of these injuries and, as a result, lengthy graft repairs, recovery of some useful function was the rule rather than the exception. Tumors involved the femoral nerve in 16 patients and included eight neurofibromas, four schwannomas, one neurogenic sarcoma, two ganglion cysts, and one leiomyosarcoma. All tumors were treated surgically and most were removed successfully.