Accelerated degeneration after failed cervical and lumbar nucleoplasty.

STUDY DESIGN

Observational cohort study.

SUMMARY OF BACKGROUND DATA

Studies evaluating the treatment of presumed discogenic spine pain using nucleoplasty have reported variable success rates. It has been suggested that these procedures lower the intradiscal pressure, reduce disk protrusion, improve disk hydration, and restore disk height. It is proposed that such structural changes in treated disks correspond to the clinical improvement in patients. Radiographic and clinical evidence showing the efficacy of nucleoplasty remains inadequate.

OBJECTIVE

To document the comparative changes in magnetic resonance imaging (MRI) the appearance of disk morphology as reflected by Pfirrmann classification scores before and after the nucleoplasty treatment in patients with continued symptoms.

METHODS

Twenty-eight consecutive patients with persistent symptoms after nucleoplasty within 1 year of treatment were evaluated. Prenucleoplasty and postnucleoplasty MRIs were evaluated and Pfirrmann scores of the symptomatic level were determined.

RESULTS

In all the treated patients, comparison between the prenucleoplasty and the postnucleoplasty MRI of the targeted disks failed to show increased signal hydration, disk space height improvement, or shrinkage of the preoperative disk bulge at a mean time of 6 months after the procedure. Of the 17 cervical levels treated in 12 patients, 5 seemed to show progressive degeneration at treated levels (42% of the patients). Of the 17 lumbar procedures in 16 patients, 4 seemed to show progressive degeneration (25% of the patients) and 1 developed a new spondylolisthesis (6.3%). Thus, 32% of the patients in our cohort showed progressive degeneration at the treated level. The median Pfirrmann score in both prenucleoplasty and postnucleoplasty was 2, and the mean Pfirrmann classification prenucleoplasty and postnucleoplasty was 1.8 and 2.1, respectively (P<0.05, 2-tailed t test).

CONCLUSION

This study failed to detect any morphologic improvement of disk abnormalities by MRI evaluation in patients with persistent pain, who then underwent nucleoplasty. Thirty-two percent showed progressive degeneration in less than 1 year after nucleoplasty, a rate greater than expected by natural progression during the interval of examination.