The timing of surgery in lumbar disc prolapse: A systematic review

Herniation of nucleus pulposus leading to leg pain is the commonest indication for lumbar spine surgery. However, there is no consensus when to stop conservative treatment and when to consider for surgery. A systematic review of literature was done to find a consensus on the issue of when should surgery be performed for herniation of nucleus pulposus in lumbar spine was conducted. Electronic database searches of Medline, Embase and Pubmed Central were performed to find articles relating to optimum time to operate in patients with herniation of nucleus pulposus in lumbar spine, published between January 1975 and 10 December 2012. The studies were independently screened by two reviewers. Disagreements between reviewers were settled at a consensus meeting. A scoring system based on research design, number of patients at final followup, percentage of patients at final followup, duration of followup, journal impact factor and annual citation index was devised to give weightage to Categorize (A, B or C) each of the articles. Twenty one studies fulfilled the criteria. Six studies were of retrospective design, 13 studies were of Prospective design and two studies were randomized controlled trials. The studies were categorized as: Two articles in category A (highest level of evidence), 12 articles in category B (moderate level of evidence) while seven articles in Category C (poor level of evidence). Category A studies conclude that duration of sciatica prior to surgery made no difference to the outcome of surgery in patients with herniation of nucleus pulposus in the lumbar spine. Ten out of 12 studies in Category B revealed that longer duration of sciatica before surgery leads to poor results while 2 studies conclude that duration of sciatica makes no difference to outcome. In category C, five studies conclude that longer duration of sciatica before surgery leads to poor outcome while two studies find no difference in outcome with regards to duration of sciatica. A qualitative and quantitative analysis was performed which favoured the consensus that longer duration of sciatica leads to poorer outcome. A systematic and critical review of literature revealed that long duration of preoperative leg pain lead to poor outcome for herniation of nucleus pulposus. Only a broad time frame (2-12 months) could be derived from the review of literature due to lack of high quality studies and variable and contrasting results of the existing studies. While surgery performed within six months was most commonly found to lead to good outcome of surgery, further studies are needed to prove this more conclusively. At this stage it is felt that time alone should not be the basis of recommending surgery and multiple other variables should be considered in a shared decision making process between the surgeon and the patient.