MRI of the post-discectomy lumbar spine

Laminectomy and discectomy are common procedures in the management of symptomatic lumbar disc herniation. Complications of such surgery include recurrent/residual disc herniation, epidural scar formation, discitis, arachnoiditis and pseudo-meningocele. Gadolinium-enhanced MRI is the technique of choice for investigating recurrent symptoms following discectomy. This article reviews the normal early and late post-laminectomy MR appearances, as well as the pathological findings associated with the above-mentioned complications.