Awake, endoscopic lumbar interbody spinal fusion: 10 years of experience with the first 400 cases.

Objective: Awake, endoscopic spinal fusion has been utilized as an ultra-minimally invasive surgery technique to accomplish the goals of spinal fixation, fusion, and disc height restoration. While many techniques exist for this approach, this series represents a single institution's experience with a large cohort and the evolution of this method.

Methods: The medical records of a consecutive series of 400 patients treated over a 10-year period were retrospectively reviewed. Endoscopic decompression, expandable intervertebral spacer deployment, and percutaneous screws were combined with liposomal bupivacaine to allow for the surgery to be performed without general endotracheal anesthesia (GETA) in the vast majority of cases. Clinical and radiographic postoperative results were reviewed with special attention to surgical complications, in particular dorsal root ganglion (DRG) irritation.

Results: All patients underwent surgery successfully without conversion to an open operation. Their mean age was 69.1 ± 10.4 years, and 42% of the patients were male. A total of 509 levels were fused, with the most common indication being spondylolisthesis (67.5%). The mean operative time was 84.6 ± 31.4 minutes, the mean intraoperative blood loss was 98 ± 63 ml, and the mean hospital length of stay was 1.93 ± 1.1 nights. Overall, 4.3% of the patients underwent planned GETA due to comorbidities, and 2% were converted to GETA intraoperatively. Eighty percent of the patients experienced > 75% improvement in leg pain, and 52% experienced > 75% improvement in axial back pain. Complications included transient DRG irritation (23%), adjacent-level disease requiring reoperation (3.5%), inadequate decompression (2.3%), and nonunion (1.8%).

Conclusions: This large case series demonstrates that awake, endoscopic spinal fusion is a viable option with acceptable clinical and radiographic results in a select patient population. Meticulous attention to detail is required to limit the rate of DRG irritation, achieve interbody height restoration, and mitigate nonunions.