Associations between physical therapy and long-term outcomes for individuals with lumbar spinal stenosis in the SPORT study.

BACKGROUND CONTEXT

A period of nonsurgical management is advocated before surgical treatment for most patients with lumbar spinal stenosis. Currently, little evidence is available to define optimal nonsurgical management. Physical therapy is often used, however its use and effectiveness relative to other nonsurgical strategies has not been adequately explored.

PURPOSE

Describe the use of physical therapy and other nonsurgical interventions by patients with lumbar spinal stenosis and examine the relationship between physical therapy and long-term prognosis.

STUDY DESIGN

Secondary analysis of the Spine Patient Outcomes Research Trial (SPORT) combining data from randomized and observational studies.

SETTING

Thirteen spine clinics in 11 states in the United States.

PATIENT SAMPLE

Patients with lumbar spinal stenosis receiving nonsurgical management including those who did or did not receive physical therapy within 6 weeks of enrollment.

OUTCOME MEASURES

Primary outcome measures included crossover to surgery, the bodily pain and physical function scales changes from the Survey Short Form 36 (SF-36), and the modified Oswestry Disability Index. Secondary outcome measures were patient satisfaction and the Sciatica Bothersomeness Index.

METHODS

Baseline characteristics and rates of crossover to surgery were compared between patients who did or did not receive physical therapy. Baseline factors predictive of receiving physical therapy were examined with logistic regression. Mixed effects models were used to compare outcomes between groups at 3 and 6 months and 1 year after enrollment adjusted for baseline severity and patient characteristics.

RESULTS

Physical therapy was used in the first 6 weeks by 90 of 244 patients (37%) and was predicted by the absence of radiating pain and being single instead of married. Physical therapy was associated with a reduced likelihood of crossover to surgery after 1 year (21% vs. 33%, p=.045), and greater reductions on the Short Form 36 physical functioning scale after 6 months (mean difference=6.0, 95% confidence interval: 0.2-11.7) and 1 year (mean difference=6.5, 95% confidence interval: 0.6-12.4). There were no differences in bodily pain or Oswestry scores across time.

CONCLUSIONS

Many patients with lumbar spinal stenosis pursuing conservative management receive physical therapy. Using physical therapy was associated with reduced likelihood of patients receiving surgery within 1 year. Results for other outcomes were mixed with no differences in several measures. Further research is needed to examine the effectiveness of physical therapy relative to other nonsurgical management strategies for patients with lumbar spinal stenosis.