Full-endoscopic trans-pars interarticularis approach for far lateral lumbar discectomy.

PURPOSE: Surgical management of far lateral disc herniations remains challenging. Current transforaminal full-endoscopic approaches require non-visualized docking in the Kambin's triangle and have been associated with significant risk of inadvertent nerve injury. We develop a full-endoscopic approach based on reliable bony landmarks allowing for visualization of the exiting nerve root prior to the far lateral discectomy. METHODS: The surgical details of a full-endoscopic trans-pars interarticularis approach for far lateral discectomy are described. These descriptions include high quality intraoperative images and important surgical pearls. A small patient cohort is presented to demonstrate feasibility and safety of the procedure. RESULTS: We demonstrate the feasibility of this approach in 14 patients with a mean age of 59.5 ± 14.7 years. At a mean follow up of 21.9 ± 6.8 months, improvement of the visual analogue scale (VAS) for leg pain was 4.3 ± 1.0 resulting in minimally clinically important difference in 78.6% of the patients. The mean improvement in VAS for the back pain was 2.6 ± 0.8 and for Oswestry disability index (ODI) was 20.6 ± 5.3. Nuances of the trans-pars surgical techniques are presented in a patient with a right-sided L4-5 far lateral disc herniation. Preoperative imaging studies, steps of the surgical progression, and intraoperative views are described in detail. CONCLUSION: Using the pars interarticularis as the bony target area allows for safe visualized access to the extraforaminal compartment of the exiting nerve root. This novel surgical technique has the potential benefit of decreasing inadvertent neural injury and subsequent postoperative dysesthesias.

Incidence and management of dural tears in full-endoscopic unilateral laminotomies for bilateral lumbar decompression.

PURPOSE: To report incidence of dural lacerations in lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) and to describe patient outcomes following a novel full-endoscopic bimanual durotomy repair. METHODS: Retrospective review of prospectively collected database including 5.5 years of single surgeon experience with LE-ULBD. Patients with no durotomy were compared with patients who experienced intraoperative durotomy, including demographics, ASA score, prior surgery, number of levels treated, procedure time, hospital length of stay (LOS), visual analogue scale, perioperative complications, revision surgeries, use of analgesics, and Oswestry Disability Index (ODI). RESULTS: In total, 13/174 patients (7.5%) undergoing LE-ULBD experienced intraoperative durotomy. No significant differences in demographic, clinical or operative variables were identified between the 2 groups. Sustaining a durotomy increased LOS (p = 0.0019); no differences in perioperative complications or rate of revision surgery were identified. There was no difference in minimally clinically important difference for ODI between groups (65.6% for no durotomy versus 55.6% for durotomy, p = 0.54). CONCLUSION: In this cohort, sustaining a durotomy increased LOS but, with accompanying intraoperative repair, did not significantly affect rate of complications, revision surgery or functional outcomes. Our method of bimanual endoscopic dural repair provides an effective approach for repair of dural lacerations in interlaminar ULBD cases.

Full-endoscopic technique mitigates obesity-related perioperative morbidity of minimally invasive lumbar decompression.

PURPOSE: Obesity is associated with increased surgical complexity and postoperative complications in spine surgery. Minimally invasive procedures have been shown to lessen some of the increased risk in obese patients. This study investigated whether utilization of a working channel endoscope can further mitigate obesity-associated challenges in spinal surgery. METHODS: A retrospective review of a single-surgeon database was conducted for all adult patients undergoing full-endoscopic unilateral laminotomies for bilateral decompression between November 2015 and March 2021. Data collected included body mass index, in operating room preparation time, procedure time, length of hospital stay, use of analgesics, complications, and quality of life measured by Oswestry Disability Index. RESULTS: Our cohort included 174 patients. Of these, 74 (42.5%) were obese. The average age was 63.6 years. In-operating room preparation time was 70.0 ± 1.7 min for obese patients and 64.4 ± 1.5 min for non-obese patients (p = 0.02). There was no difference in operative time, durotomy rates or other perioperative complications between obese and non-obese patients. Hospital length of stay trended toward longer in the obese group, but did not reach significance. A greater percentage of obese patients were still using both narcotic and non-narcotic pain medications 2 weeks after surgery. There was no significant difference in functional outcomes between groups. CONCLUSION: Full-endoscopic unilateral laminotomies for bilateral decompression are safe and effective in both non-obese and obese patients. The use of an endoscope can partially mitigate obesity-related morbidity in lumbar decompression. However, obesity is significantly related to increased postoperative analgesic use.