Abstract
Introduction
Patients with recurrent low back pain (LBP) exhibit changes in postural control. Stereotypical muscle activations resulting from external perturbations include anticipatory (APAs) and compensatory (CPAs) postural adjustments. This study aimed to determine differences in postural control strategies (APAs and CPAs) between those with and without lumbar disc degeneration (LDD) and LBP.
Methods
Ninety-seven subjects participated in the study (mean age 50 years (SD 12)). 3T MRI was used to acquire T2 weighted images (L1-S1). LDD was determined using Pfirrmann grading and LBP using the numerical rating scale (NRS). A bespoke perturbation platform was designed to deliver postural perturbations. Electrical activity was analysed from 16 trunk and lower limb muscles during four typical APA and CPA epochs. A Kruskal-Wallis H test with Bonferroni correction for multiple comparisons was conducted.
Results
Four groups were identified; ‘no LDD no pain’ (n = 19), ‘LDD no pain’ (n =38), ‘LDD pain’ (n =35) and ‘no LDD pain’ (n = 5). There was no significant difference in age or gender between groups. Although, increased BMI was associated with LBP it did not correlate with significant findings.
Significant differences in APAs and CPAs were observed between ‘LDD pain’ and ‘LDD no pain’ groups during predicted and unpredicted perturbations (p=0.009–0.049, r=0.31–0.43). Significant CPAs correlated with LBP (p=0.001–0.03) but did not correlate with LDD (p=0.22–0.94).
Conclusion
Postural control strategies are different between those with LDD and pain and those without. Differences in compensatory strategy are associated with the presence of pain and not LDD.
No conflicts of interest.
Sources of Funding: Janet Deane is funded by an Allied Health Professional Doctoral Fellowship awarded by Arthritis Research U.K. (ARUK).
