Temporal Changes in Improvement and Recovery Kinetics Following Transforaminal Endoscopic Lumbar Discectomy and Foraminotomy

Introduction: Lateral disc herniations are often deep to the facet joint; due to iatrogenic instability following decompression and discectomy, fusion may be required to address these herniations. As transforaminal endoscopic lumbar discectomy (TELD) has become a common treatment for lateral disc herniations, it is important to understand postoperative recovery timelines to facilitate perioperative counseling. Few studies have investigated the rate of postoperative improvement over different follow-up time points after TELD. We hypothesize that the majority of progress following TELD occurs within 6 weeks, after which there is a plateau of progress.

Methods: Patients who underwent primary one- or two-level TELD for lateral disc herniations with 6-month follow-up were included. Outcomes included: patient reported outcomes (PROMs), including Oswestry Disability Index (ODI), 12-Item Short Form Survey Physical Component (SF-12 PCS), and Visual Analog Scale (VAS) for back and leg pain; PROMs minimal clinically important difference (MCID); global rating of change (GRC); and return to activities. Timepoints analyzed were preoperative and postoperative 2 weeks, 6 weeks, 12 weeks, 6 months. Improvement trends were graphed; a vertical line on the graph indicates a “plateau”, where the respective time point does not have a statistically significant difference with the following time point on paired samples t-test or Fisher’s exact test.

Results: 51 patients were included. Compared to the previous time point, there were significant improvements in VAS back and leg at 2 weeks and 6 weeks, with a plateau after 6 weeks. ODI and SF-12 PCS did not experience significant improvement until 6 weeks, which was also the plateau point. Percent of patients who achieved VAS leg MCID and improvement on GRC peaked at 6 weeks. All patients returned to driving and discontinued opioids postoperatively, and most patients (90.9%) returned to work. Median days to return to driving, work, and discontinue opioids were 8, 35, and 1, respectively.

Conclusion : Patients can expect the majority of postoperative improvement to occur within 6 weeks, after which improvements tend to plateau. Around 75% of patients feel better at 6 months compared to preoperatively. Given most patients experience significant improvement after TELD, this surgery may spare some patients from a fusion procedure.