Effect of Duration of Symptoms on the Clinical and Functional Outcomes of Lumbar Microdiscectomy: A Randomized Controlled Trial

OBJECTIVES: The objective is to determine whether the preoperative duration of symptoms can affect the clinical and functional outcomes after microdiscectomy. METHOD: This study is a single blind randomized controlled trial with level 1 evidence. From 3 January 2016 to 15 February 2017, 122 adult patients with symptomatic lumbar disc herniation were divided randomly by computer system into three groups were treated by microdiscectomy at 6 weeks, 3 months and 6 months from onset of symptoms respectively. Ninety‐seven patients, age (19–47) years, 42 males and 55 females, were analyzed at the end of this study with 3 years of follow up. Primary outcome measures are Oswestry Disability Index (ODI), Roland‐Morris Questionnaire (RMQ) and Visual Analogue Scale (VAS) for back pain and leg pain. Secondary outcome measures are post‐operative complications, length of hospital stay and time of return to daily activities. RESULTS: There was significant difference in VAS for back pain among study groups (P = 0.002) at 2 weeks). There were significant differences in VAS for leg pain among study groups (P < 0.001) at 2 weeks and at 3 months (P = 0.003). There was significant difference in ODI among study groups at 2 weeks, 3, 6 months, 1, 2 and 3 years (P = 0.037 at 2 weeks and P < 0.001 at other periods of assessments) and we found that the mean of ODI in group 6 weeks was better than group 3 months and this was better than group 6 months in all periods of assessment. Group 6 weeks was better than group 3 months and this was better than group 6 months in postoperative improvements regarding RMQ with significant difference at 2 weeks postoperatively (P < 0.001) and at 3 months postoperatively (P < 0.001). CONCLUSION: Duration of preoperative symptoms, in patients with lumbar disc herniation, can affect the clinical and functional outcomes after lumbar microdiscectomy as the shorter duration of symptoms resulted in better postoperative clinical and functional outcomes.