Reliability of the Path of the Sciatic Nerve, Congruence between Patients' History and Medical Imaging Evidence of Disc Herniation and Its Role in Surgical Decision Making

STUDY DESIGN: The prevalence of disc herniation is estimated to be about 100,000 new cases per year in France and disc herniation accounts for 25% to 30% of surgical activity in Departments of Neurosurgery. Classically, sciatica is expected to follow its specific dermatome-L5 or S1-. In clinical practice, we regularly encounter patients showing discrepancy between clinical sciatica and imaging findings. PURPOSE: The aim of this paper is to review the medical concept and management of sciatica pain in patients showing this discrepancy. OVERVIEW OF LITERATURE: To the best of our knowledge, this subject has not yet been discussed in the medical literature. METHODS: The medical records of 241 patients who were operated on for L5 or S1 sciatica caused by disc herniation were reviewed. RESULTS: We found an apparent clinicoradiological discrepancy between sciatica described by patients on one side and magnetic resonance imaging (MRI) finding on the other side in 27 (11.20%) patients. We did not find any other abnormalities in the preoperative and postoperative period. All of these patients underwent lumbar discectomy via posterior interlaminar approach. Three months after surgery, 25 patients (92.59%) had been totally relieved of sciatica pain. Two patients (7.41%) continued to experience sciatica in spite of the surgery. CONCLUSIONS: The discrepancy between clinical sciatica and disc herniation level on MRI is not rare. Management of this discrepancy requires further investigation in order to avoid missing the diagnosis and treatment failure.