Abstract
Purpose and Background
This pilot study aimed to determine the accuracy of lumbar spine combined movement (CM) testing for diagnosing facet joint mediated pain, by comparing CM to medial branch blocks (MBB) - the gold standard in the diagnosis of facet joint pain. A regular compression pattern of CM combines active extension and lateral flexion, which is believed to compress the facet joints greater than physiological uni-planar movements.
Method and Results
96 patients attending a pain clinic day case unit for diagnostic MBB were recruited. Patients' pain responses to CMs were measured prior to and thirty minutes following MBB. The effect of weight bearing and recumbence, RMDQ, EQ-5D and MYMOP were also measured. The regular compression CM test had 80% sensitivity (95%CI: 71% to 89%) and 50% specificity (95%CI: 28% to 71%). The regular compression CM group had the largest pre-post VAS difference (median 4 points). The patients whose pain was not relieved in recumbence (n=15) showed a significant VAS difference of 6 points p=0.001). There was a significant positive correlation between the pre and post pain scores, p<0.001. There was no association between MBB response and RMDQ, EQ-5D, MYMOP scores, duration of symptoms or standing as a provoking activity.
Conclusion
Regular compression CM testing can be used as a diagnostic tool to identify patients with facet joint mediated pain, particularly when associated with high pain scores. Low back pain (LBP) provoked by standing and relieved with recumbence are common features in the LBP population but are not indicators of facet joint pathology, contrary to many clinicians' beliefs.
