Magnetic resonance imaging of the postoperative intervertebral disk: the first eight months--clinical and legal implications.

Ten patients were followed prospectively after lumbar discectomy, both clinically and with MR imaging, from 2 days to 8 months. The usefulness of MR imaging is limited during the first 2-3 months postsurgery because of severe disruption of the intraspinal anatomic definition. Thus, abnormal MRI findings during this initial period do not correlate with the clinical symptom-free state of patients postsurgery. The use of MR imaging in symptomatic patients is therefore limited.