Vibration pain provocation can improve the specificity of MRI in the diagnosis of symptomatic lumbar disc rupture.

OBJECTIVE

The purpose of this study was to determine if vibration pain provocation could be combined with magnetic resonance imaging (MRI) to increase its specificity in identifying symptomatic disc disruption identified by discography.

DESIGN

Prospective single-blind study.

SETTING

Data were collected at a spine specialty clinic and at a diagnostic imaging center.

PATIENTS

A total of 206 discs in 78 patients (41 males, 37 females; average age, 39.7 years; range, 18-73 years) were evaluated by MRI, spinous process vibration, and discography.

INTERVENTIONS

A hand-held prototype vibrator was applied to the spinous process of each intervertebral disc level to be evaluated. The type of pain provoked with vibration as well as with discography was recorded as painless, dissimilar to clinical pain, or similar/exact reproduction of clinical pain. The discograms and MRI scans were scored on a 0-4 scale. A system was defined for combining the vibration results with MRI.

OUTCOME MEASURES

The results of the vibration and MRI were compared with the results of computed tomography/discography to determine how well the results of the evaluations agreed.

RESULTS

Vibration pain provocation agreed with discographic pain provocation in 70.9% of the discs. The specificity of MRI compared with discographic findings was only 55.7%. However, this figure improved significantly to 81.3% when relying on the vibration pain provocation in discs with mild or moderate disruption. The sensitivity of the combined evaluation was 85.9% and the accuracy 83.0%.

CONCLUSIONS

A small hand-held vibrator could produce pain provocation results similar to those obtained by discography. Results of this noninvasive pain provocation method can improve the specificity and accuracy of MRI in identifying symptomatic disc lesions.