Endoscopic Transforaminal and Lateral Recess Decompression After Previous Spinal Surgery.

BACKGROUND: Leg pain and back pain after lumbar laminectomy and spinal decompression fusion surgery are common and often related to persistent lumbar foraminal or lateral recess stenosis. Although persistent symptoms often stem from incomplete decompression during the primary index surgery, recurrent symptoms may also be the result of intervertebral cage subsidence due to loss of intervertebral and neuroforaminal height.
OBJECTIVE: The aim of this study was to investigate the feasibility of using the outpatient transforaminal decompression procedure as an alternative to inpatient open procedure in revision decompression surgery, with the intent of minimizing the incidence of perioperative and postoperative surgical complications while reducing both direct and indirect costs of surgical treatment, shortening time to patient postoperative narcotic independence, and shortening time of patient return to daily activities.
METHODS: A total of 48 patients with conclusive diagnostic imaging and interventional workup underwent endoscopic transforaminal and lateral recess decompression for both persistent or recurrent leg and/or low back pain following previous lumbar laminectomy (22 patients) or decompression fusion surgery (26 patients). In addition to radiographic studies, patients were followed for a minimum of 2 years postoperatively, and clinical outcomes were evaluated with the visual analog scale (VAS), Oswestry Disability Index (ODI), and modified Macnab criteria.
RESULTS: At final follow-up, patients with single- and 2-level prior surgeries reported an average ODI reduction following their secondary surgery of 44.6%, with an average final score of 14.8. Less favorable ODI score reductions following secondary surgery (23.8%) were reported by patients who had more than one or a complex prior multilevel surgery. According to the modified Macnab criteria, "excellent" and "good" results were obtained with the secondary surgery in 79.1% (38 of 48) of patients with no more than a single 1- or 2-level prior lumbar surgery. The mean VAS score decreased from 7.7 ± 1.8 preoperatively to 2.3 ± 1.1 at final follow-up (P < .01). Fair and poor results with the secondary surgery were seen in 20.9% (10 of 48) of patients with several prior surgeries or complex multilevel previous lumbar surgeries. The level distribution for secondary surgery was as follows: L4-5 segment (26 levels; 54.1%), L5-S1 (14 levels; 29.2%), L3-4 (7 levels; 14.6%), and the L2-3 level (1 level; 2.1%). Postoperative complications were limited to irritation of the dorsal root ganglion, which occurred in 25% (12 of 48) of patients. There were no wound infections, nerve root injuries, foot drop, or admissions to a hospital for further postoperative care. All patients with "excellent" and "good" outcomes measured by modified Macnab criteria, who were working before and after the primary and secondary surgeries (27 of 38), reported earlier return to work after the endoscopic outpatient surgery (2.6 ± 0.8 weeks) than with the prior inpatient open spinal surgery (8.1 ± 4.5 weeks). Based on the 2012 Medicare fee schedule for professional fees, direct costs were 40.6% and indirect costs were 37.1% lower with the secondary endoscopic surgery compared with primary open surgery.
CONCLUSIONS: Transforaminal decompression is an effective alternative to open revision lumbar spinal surgery to treat symptomatic spinal stenosis after previous lumbar surgery in patients with persistent or recurrent leg and low back pain. It can be safely done in an outpatient setting, while realizing savings in direct and indirect costs.