Effectiveness of Physical Therapy for the Management of Chronic Spine Disorders: A Propensity Score Approach

Abstract

Evidence on the effectiveness of physical therapy for the management of chronic spine disorders is limited. The purpose of this study was to use a large current database, the National Spine Network database, to assess the effectiveness of physical therapy in the management of chronic spine disorders. The participants were people who had spine problems lasting 3 months or longer and who were seen for an initial visit and a follow-up visit (N=4,479) at 1 of 17 US spine centers. A propensity score approach was used to create a matched sample of participants who received physical therapy (intervention group) and participants who did not receive physical therapy (control group). The 2 groups were similar with regard to more than 50 baseline characteristics. Outcomes were assessed with the Oswestry Disability Index (ODI) and the 36-Item Short-Form Health Survey (SF-36). Both the intervention and control groups improved between the initial and the follow-up visits on ODI scores and on SF-36 physical function, role physical, and bodily pain scores. Although the amount of improvement in the outcome measures was significantly greater for the intervention group than for the control group, the differences were small (3-5 points). When the subgroup of participants who had the greatest propensity for receiving physical therapy was examined, differences in the amount of improvement between the intervention and control groups were larger (5-13 points). Physical therapy was effective in the management of chronic spine disorders in participants with the greatest propensity for receiving physical therapy. When the entire sample was considered, differences in the amount of improvement between the intervention and control groups were not clinically relevant.