RESUMO
STUDY DESIGN: A retrospective study OBJECTIVES: To try and find the best surgical technique by analyzing the real-time video taken during a percutaneous endoscopic interlaminar lumbar discectomy. SUMMARY OF LITERATURE REVIEW: A percutaneous endoscopic lumbar discectomy, using an interlaminar approach, has superior aspects, such as anatomical similarity with that of open spinal surgery, and applicability regardless of the herniated level. However, the technical difficulty can be an obstacle to shortening of the learning-curve. MATERIALS AND METHODS: Between January 2005 and January 2006, 56 patients who were underwent an operation at our hospital, due to single level (L4-5 or L5-S1) herniated lumbar disc disease, by one surgeon, and were selected for this study. The procedure was divided by the approach; either ligament flavum resection, partial removal of the lamina or root identification and discectomy. By analyzing the real-time video taken during the operation, as well as checking the time taken for each procedure, the factors influencing the prolongation of surgery time can be sought, and efforts made to shorten the operation time. RESULTS: The mean operation time was 65 minutes (28 minutes~127 minutes). The mean operation times in patients either requiring or not requiring partial removal of the lamina were 84 minutes (45 minutes~127 minutes) and 45 minutes (28 minutes~91 minutes), respectively, and also showed a statistically significant correlation (p=0.023). The mean operation times for the first and last 10 cases were 107 and 48 minutes, respectively. 3 cases needed revision open surgery due to failed symptom resolution. The procedures affecting a prolonged operation time were partial removal the lamina and ligament flavum resection. The time required for ligament flavum resection plateaued after 20 cases, and that for partial removal of the lamina reached plateau after 19 cases. CONCLUSIONS: By overcoming such technical problems, shortening of the learning-curve for a percutaneous endoscopic interlaminar lumbar discectomy was possible.