Back pain is also improved by lumbar disc herniation surgery

Background and purpose — Indication for lumbar disc herniation (LDH) surgery is usually to relieve sciatica. We evaluated whether back pain also decreases after LDH surgery. Patients and methods — In the Swedish register for spinal surgery (SweSpine) we identified 14,097 patients aged 20–64 years, with pre- and postoperative data, who in 2000–2016 had LDH surgery. We calculated 1-year improvement on numeric rating scale (rating 0–10) in back pain (N(back)) and leg pain (N(leg)) and by negative binomial regression relative risk (RR) for gaining improvement exceeding minimum clinically important difference (MCID). Results — N(leg) was preoperatively (mean [SD]) 6.7 (2.5) and N(back) was 4.7 (2.9) (p < 0.001). Surgery reduced N(leg) by mean 4.5 (95% CI 4.5–4.6) and N(back) by 2.2 (CI 2.1–2.2). Mean reduction in N(leg)) was 67% and in N(back) 47% (p < 0.001). Among patients with preoperative pain ≥ MCID (that is, patients with significant baseline pain and with a theoretical possibility to improve above MCID), the proportion who reached improvement ≥ MCID was 79% in N(leg) and 60% in N(back). RR for gaining improvement ≥ MCID in smokers compared with non-smokers was for N(leg) 0.9 (CI 0.8–0.9) and ­N(back) 0.9 (CI 0.8–0.9), and in patients with preoperative duration of back pain 0–3 months compared with > 24 months for N(leg) 1.3 (CI 1.2–1.5) and for N(back) 1.4 (CI 1.2–1.5). Interpretation — LDH surgery improves leg pain more than back pain; nevertheless, 60% of the patients with significant back pain improved ≥ MCID. Smoking and long duration of pain is associated with inferior recovery in both N(leg) and N(back).