A randomized clinical trial comparing extensible and inextensible lumbosacral orthoses and standard care alone in the management of lower back pain

Abstract

Study design: Single blinded, randomized clinical trial for the evaluation of lumbosacral orthoses (LSOs) in the management of lower back pain (LBP).

Objective: To evaluate the effects of two types of LSOs on self-rated disability in patients with LBP.

Summary of background data: LSOs are commonly used for the management of LBP, but their effectiveness may vary because of design. An inextensible LSO (iLSO) reduces trunk motion and increases trunk stiffness, whereas an extensible LSO (eLSO) does not.

Methods: A total of 98 participants with LBP were randomized to 3 groups: (1) standard care (SC) group, which included medication and physical therapy (n = 29), (2) SC with eLSO (eLSO group) (n = 32), and (3) SC with iLSO (iLSO group) (n = 37). Outcome measures were evaluated before and after 2 weeks of treatment: modified Oswestry Disability Index (ODI), Patient Specific Activity Scale, pain ratings, and Fear Avoidance Beliefs Questionnaire.

Results: There were no statistically significant differences between groups at baseline. Compared with the SC alone, iLSO group showed greater improvement on the ODI scores (P = 0.01) but not the eLSO group. The ODI scores improved by a mean of 2.4 (95% confidence interval [CI], 2.2-7.1), 8.1 (95% CI, 2.8-13.4), and 14.0 (95% CI, 8.2-19.8) points for SC, eLSO, and iLSO groups, respectively. Individuals wearing the iLSO had 4.7 times higher odds of achieving 50% or greater improvement in the ODI scores than those assigned to SC (95% CI, 1.2-18.5, P = 0.03). Both the eLSO and iLSO groups had a greater improvement in the Patient Specific Activity Scale scores than the SC group (P = .05 and P = 0.01, respectively), but the change did not meet the minimal clinically important difference. Pain ratings improved for all 3 groups, with no statistical difference between them. Finally, no significant differences across groups were found for the Fear Avoidance Beliefs Questionnaire.

Conclusion: An iLSO led to greater improvement in ODI scores than SC and an eLSO. We surmise that the likely mechanism responsible for this difference in outcome was the added trunk stiffness and motion restriction by the iLSO.

Level of evidence: 2.

Figures

Figure 1

Flow Diagram of Study Participants Throughout the Study Period. Standard care (SC) included medication, advice, and physical therapy. The eLSO intervention consisted of an extensible orthosis plus standard care (eLSO). The iLSO intervention consisted of an inextensible orthosis plus standard care (iLSO).

Figure 2

Mean Oswestry Disability Index Scores for Each Treatment Group: Pre and Post Treatment. Mean scores and confidence intervals for the Oswestry Disability Index (ODI) at baseline and at 2-weeks for the standard care (SC), extensible orthosis (eLSO+SC), and inextensible orthosis (iLSO+SC) groups.