A study of patients with chronic sciatica caused by lumbar disc herniation has found that microdiscectomy is superior to conservative non-surgical care with respect to pain intensity at six months of follow-up. This was the conclusion drawn by researchers at London Health Services (London, Canada) whose findings were published in the New England Journal of Medicine.
Led by Chris S Bailey, the study team sought to establish whether discectomy or a conservative approach is the better treatment option for sciatica that has persisted for between four to 12 months. The single-centre trial saw sciatica patients with lumbar disc herniation at the L4–L5 or L5–S1 level randomised in a 1:1 ratio to undergo microdiscectomy or to receive six months of standardised non-operative care, followed by surgery if needed. Surgery was performed by spine surgeons who used conventional microdiscectomy techniques. The non-surgical care included education of patients regarding day-to-day functioning and exercise, use of oral analgesics, and the use of physiotherapy provided at the discretion of physiotherapists not associated with the trial.
The primary outcome assessed by the study team was the intensity of leg pain on a visual analogue scale (ranging from 0–10 , with higher scores indicating more severe pain) at six months after enrolment. Secondary outcomes were the score on the Oswestry Disability Index, back and leg pain, and quality-of-life scores at six weeks, three months, six months, and one year.
From 2010 to 2016, a total of 790 patients were screened for eligibility in the study. In total 128 patients were enrolled, with 64 in each group. Among the patients assigned to undergo surgery, the median time from randomisation to surgery was 3.1 weeks. Of the 64 patients in the non-surgical group, 22 (34%) crossed over to undergo surgery at a median of 11 months after enrolment. At baseline, the mean score for leg-pain intensity was 7.7 in the surgical group and 8.0 in the nonsurgical group.
Outlining the results, Bailey and colleagues note that the primary outcome of the leg-pain intensity score at six months was 2.8 in the surgical group and 5.2 in the non-surgical group (adjusted mean difference, 2.4; 95% confidence interval, 1.4 to 3.4; P<0.001). Secondary outcomes including the score on the Owestry Disability Index and pain at 12 months were in the same direction as the primary outcome. Nine patients had adverse events associated with surgery, and one patient underwent repeat surgery for recurrent disc herniation.
Discussing the findings, Bailey and colleagues write: “In our single-centre trial involving patients with sciatica lasting four to 12 months caused by lumbar disc herniation at the L4–L5 or L5–S1, surgery resulted in less leg pain at six months than non-surgical treatment. Randomised trials have shown a beneficial treatment effect for surgery over conservative care in the first six months among patients with lumbar disc herniation. However, in some randomised trials, the patients had symptoms for a shorter duration than the minimum of four months required for entry in our trial.”
In conclusion, they add: “We found that patients who underwent surgery for sciatica lasting four to 12 months caused by lumbar disc herniation had a greater reduction in pain at six months than those who received conservative treatment.”