Lower half Laminectomy for Lumbar Disc Herniation A study of 350 cases in last decade

Background: Lumbar disc herniation is one of the most commonly encountered problems in daily neurosurgical practice. Microdiscectomy or open discectomy (MD/OD) are the standard procedures for symptomatic lumbar disc herniation and they involve removal of the offending intervertebral disc compressing the nerve root. Discectomies are done in several ways like laminectomy and discectomy, Microdiscectomy, Endoscopic discectomy etc. We are practicing lumbar discectomy without sophisticated instruments without the aid of headlight loupe or microscopic magnification. Aim: To study the clinicoradiological profile of the patients who underwent the surgical management of the herniated lumbar disc without magnification under spinal anaesthesia and their outcome. Material and Methods: This is a study conducted in department of neurosurgery, Nil Ratan Sircar medical college, Kolkata from January 2010- December 2017. 350 patients were operated for symptomatic lumbar disc herniation under spinal anaesthesia. Lower 1/3rd laminectomy of the upper vertebra, shaving of overhanging spinous process, trimming of upper margin of lower vertebra, removal of yellow ligament and discectomy was done. In L5S1 disc prolapsed only ligamentum flavum was removed, No laminectomy was performed. Exclusion criterias included patients with more than 2 level discectomies and high lumbar Disc Herniation. Results: Of these 350 patients, 1220 patients were Male, 130 patients were Female. Most common age group was between 40 – 60 years. 250 patients had single level disc herniation. Out of 250 patients, In 126 patients L5 S1 discectomy was done, In 103 patients L4 L5 level, in rest 21 patients L3 L4 was intervened. In 100 patients Two level discectomy was done. The duration of surgery was less than 1 hr in 91% of cases. The most common complication was surgical site infection. In accordance to Odom”s criteria the results were ranging from excellent to good recovery in 90 % of patients during discharge. No listhesis was detected radiologically in the post operative period. Conclusion: All cases were done in spinal anaesthesia. Due to minimal laminectomy, less chances of listhesis post operatively. Adequate exposure is obtained. The duration of stay in hospital is less. The learning curve is less as compared to microscopic or endoscopic procedures. This procedure can be done with minimal requirement of instruments During discectomy the thickened ligamentum flavum (causing canal stenosis/narrowing) can also be delt in single Procedure. Hence, This procedure is also equally effective as other procedures carried out for lumbar discectomy.