LAUSR

STUDY DESIGN Controlled radiologic follow-up study. OBJECTIVE To ascertain if changes in cord excursion with SLR at 1.5-year follow-up time accompany changes in clinical symptoms SUMMARY OF BACKGROUND DATA.: Lumbar intervertebral disc herniation (LIDH) is known to be a key cause of sciatica. Previously we found that a significant limitation of neural displacement (66.6%) was evident with the straight leg raise test (SLR) on the symptomatic side of patients with sub-acute single level posterolateral LIDH. METHODS 14 patients with significant sciatic symptoms due to a sub-acute single level posterolateral LIDH were re-assessed clinically and radiologically at 1.5 years follow up with a 1.5T MRI scanner. Displacement of the conus medullaris during the unilateral and bilateral SLR was quantified reliably with a randomized procedure and compared between SLRs and to data from baseline. Multivariate regression models and backward variable selection method were employed to identify variables more strongly associated with decrease in low back pain (LBP) and radicular symptoms. RESULTS Compared to previously presented baseline values, the data showed a significant increase in neural sliding in all the quantified maneuvers (p≤0.01), and particularly of 2.52 mm (p≤0.001) with the symptomatic SLR.Increase in neural sliding correlated significantly with decrease of both radicular symptoms (Pearson=-0.719, p≤0.001) and low back pain (Pearson=-0.693, p≤0.001). Multivariate regression models and backward variable selection method confirmed that improvement of neural sliding effects (p≤0.004) as the main variable being associated with improvement of self-reported clinical symptoms. CONCLUSIONS To our knowledge, these are the first non-invasive data to objectively support the association between increase in magnitude of neural adaptive movement and resolution of both radicular and LBP symptoms in in-vivo and structurally intact human subjects. LEVEL OF EVIDENCE