We carried out MRI studies of 74 patients with end-plate and vertebral bone-marrow changes associated with degenerative lumbar disc disease. Abnormalities were classified into type A, with decreased signal intensities, and type B, with increased signal intensities on T1-weighted spin-echo images. Twenty-seven (73%) of the 37 patients with type-A changes had low back pain, in contrast to only four (11%) of the 37 patients with type-B changes. Lateral flexion-extension radiographs showed hypermobility in 26 patients (70%) with type-A changes, and in only six (16%) with type-B changes. Type-A changes correlated with segmental hypermobility and low back pain, while type-B changes were more common in patients with stable degenerative disc disease.

We studied the use of gadolinium diethylenetriaminepentaacetic acid-enhanced MRI in the detection of pathological changes in the nerve roots of 25 patients with unilateral sciatica due to lumbar disc herniation. Enhancement was observed in the affected nerve roots within the root sleeve at the caudal edge of the herniation and was classified into three categories: grade 0, none; grade 1, enhancement restricted to a focal region within the sleeve; and grade 2, diffuse and homogeneous. The grade of enhancement correlated well with the severity of the sciatica, and was considered to be due to a disruption of the blood-nerve barrier, leading to oedema.