Association between MRI findings and clinical outcomes in a period of 5 years after lumbar spine microdiscectomy

Background To evaluate the associations between magnetic resonance imaging (MRI) findings and pain, disability and quality of life before surgery and up to 5 years after lumbar microdiscectomy. Materials and methods Sixty-one patients who underwent one-level lumbar microdiscectomy by the same surgeon participated in this analytic, observational, prospective study. Lumbar spine MRI was performed preoperatively and 5 years postoperatively. Pain, disability and quality of life were measured with VAS, ODI, Roland Morris and SF-36 pre- and up to 5 years postoperatively. Subsequently associations between radiological findings and clinical outcomes were recorded. Results Before surgery patients with disc extrusion or sequestration, with increased thecal sac compression ( d > 2/3), with Modic changes (MC) 2 and 3 on the operated level and Pfirrmann grades IV and V on the operated and both adjacent discs presented the worst preoperative clinical outcomes. MC preoperatively were not related with postoperative results, in contrast with the type of disc herniation and thecal sac compression. Preoperative Pfirrmann grade IV and V on the operated and both adjacent discs and postoperative MC 2 and 3 on the operated level were related to poor clinical outcomes 36–60 months post-discectomy. Conclusions Extrusion or sequestration of the operated disc, increased compression of thecal sac, MC 2 and 3 on the operated level and Pfirrmann grades IV and V on the operated and adjacent discs were associated with the worst clinical outcomes. Nerve root impingement, facet joint arthritis, perineural fibrosis and disc granulation tissue had no effect on clinical scores.