Study design: A prospective controlled study of patients without low back pain observed after experimental lumbar discography.
Objectives: To determine whether discography may cause long-term low back symptoms in selected patients.
Background: Lumbar discography is generally considered safe, although controversial, with few complications. There is little information on long-term follow-up of asymptomatic patients after experimental discography.
Methods: Twenty-six patients without pre-existing low back pain were observed for 1 year after lumbar discography to determine the effects of lumbar discography in three experimental groups: 10 patients who had remote cervical spine surgery with excellent results (pain-free group); 10 patients who had the same surgery with poor results (chronic pain group); and 6 patients who had primary somatization disorders. Two control groups were also observed: a group of patients with somatization disorder who were similarly evaluated but without discography, a group of patients with low back pain observed for 1 year after discography without surgery.
Results: In the three experimental groups (no back pain before discography) no subject with normal psychometric testing had persistent pain after discography (0/11), whereas 6 (40%) of 15 with abnormal psychometric test results reported significant new low back pain. None of the pain-free group (0/10), 20% of the chronic neck pain group (2/10), and 66% of the somatization group (4/6) continued to have significant back pain 1 year after injection. Psychological testing and occupational disability strongly predicted continued pain after discography. The control groups had no significant change in low back symptomatology during the year of observation.
Conclusion: Discography in a subject group without low back pain but with significant emotional and chronic pain problems may result in reports of significant back pain for at least 1 year after injection. Subjects with normal psychometric test results had no reports of significant long-term back pain after discography.