Evaluating how preoperative symptom predominance is associated with outcomes following uniportal full-endoscopic lateral recess decompression: a comparative cohort study

Background: Patients with lumbar lateral recess stenosis present with varying degrees of radicular leg pain and axial back pain, yet the exact impact of each preoperative symptom on postoperative outcomes following full-endoscopic decompression remains poorly understood. Existing literature does not stratify patients by symptom profile, revealing a gap that could inform patient selection and preoperative counselling. This study aimed to evaluate clinical outcomes between back pain-predominant (BP) and leg pain-predominant (LP) patients following endoscopic unilateral uniportal lateral recess decompression.

Methods: A retrospective cohort study was performed on patients with magnetic resonance imaging (MRI)-confirmed single-level lumbar lateral recess stenosis who underwent isolated unilateral index-level lateral recess decompression using a full-endoscopic uniportal approach. Patients were stratified into BP and LP groups according to preoperative symptom predominance, while patients with equivalent back and leg pain scores were excluded. Baseline characteristics, postoperative patient-reported outcome measures (PROMs), changes from baseline, and minimal clinically important difference (MCID) attainment [defined as a ≥2-point improvement in Visual Analog Scale (VAS) scores] were compared using independent t-tests and Fisher’s exact tests.

Results: A total of 50 patients were included, comprising 19 BP and 31 LP patients. Median follow-up was 5 months (interquartile range, 2–6 months). Baseline demographic and perioperative characteristics were comparable between groups (all P>0.05). BP patients reported higher preoperative VAS back pain scores (7.16±1.89 vs. 4.35±2.99, P<0.001), whereas LP patients reported higher VAS leg pain scores (7.81±1.83 vs. 3.53±2.99, P<0.001). Preoperative VAS numbness and North American Spine Society (NASS) scores were similar between groups. Postoperative PROMs were comparable across all domains (all P>0.05). However, BP patients demonstrated greater improvement in VAS back pain (5.11±3.35 vs. 2.29±3.33, P=0.006), while LP patients achieved greater improvements in VAS leg pain (6.23±3.43 vs. 2.47±3.15, P<0.001) and NASS neurogenic symptoms (37.77±26.14 vs. 21.58±19.44, P=0.02). MCID attainment for leg pain was higher in the LP group [90.3% vs. 52.6%; OR 8.40, 95% confidence interval (CI): 1.89–37.40; P=0.005].

Conclusions: No statistically significant between-group differences were noted in postoperative outcomes following full-endoscopic uniportal lateral recess decompression, suggesting that axial back pain predominance should not preclude surgical candidacy. Recovery patterns differed according to symptom profile, with BP patients experiencing greater back pain relief and LP patients demonstrating greater improvement in leg pain and neurogenic symptoms. These findings support individualized preoperative counselling and expectation management. Prospective studies with larger cohorts and longer follow-up are needed to validate these findings.