Interlaminar Discectomy in Lumbar Disc Herniation: Surgical Experience and Results

Aim of the Study: Is to evaluate interlaminar discectomy in terms of: accessibility, safety and clinical outcome.

Background: Interlaminar approach for lumbar Discectomy is a less invasive technique that allows accessibility to a herniated disc via resection of ligamentum flavum either partially or totally with preservation of other structures leading to better spinal stability.

Study Design: Prospective study.

Patients and Methods: This is a prospective study including 64 cases of lumbar disc herniation operated between august 2012 and February 2015. All cases were subjected to lumbar discectomy via interlaminar approach. Surgical technique based on resection of ligamentum flavum either unilateral or bilateral with foraminotomy before disc extraction. Visual Analog Scale was used for preoperative and postoperative pain assessment, while Spengler´s modification of Macnab´s criteria was used for long term follow up. Patients were follow up for a period ranged from 3 to 18 months.

Results: Adequate exposure of herniated discs and involved roots obtained in 61 cases where partial laminectomy was need in 3 cases. In these 3 cases, the herniated disc showed cephalic migration. Bilateral resection of ligamentum flavum was done in 11 cases. All cases presented with sciatica showed excellent post-operative improvement, cases with foot drop showed no improvement. Early ambulation was done in all cases.

Conclusion: Interlaminar approach in lumbar discectomy is a safe and effective technique providing excellent accessibility in the majority of cases -even with higher levels like L3-4- with less post-operative back pain and early ambulation. Cases with cephalic migration of the herniated discs needs partial laminectomy.