Sixty cases with mechanical changes were seected out from one hundred cases presented by lumbar disc disease. The majority were over 40years. Pain was the main symptom. Sacroiliitis was the commonest 2ry mechanical changes, presented in the sixty cases. Tender knee was the second commonest mechanical change. Post operative, (14) cases not improved regarding sacroiliitis. They had pre-op. duration more than 6 months, one case only not improved with pre-op. duration less than 6 months. Operative techniques used are either open laminectomy and discectomy or microdiscectomy.