Paper #1. How Effective is Physical Therapy for Low Back Pain? A Multivariate Analysis of 4597 Patients.

Background/Introduction: Axial low back pain is a major cause of morbidity and disability in health care. Previous studies have found questionable efficacy for surgery in the absence of specific indications (instability, neoplasm, infection, etc.). Nonoperative treatments are available, however there is scant evidence as to the efficacy of PT and risk factors on outcomes. The purpose of this study is to evaluate whether the treatment of nonspecific low back pain with physical therapy (PT) results in clinically significant improvements in patient-reported pain and functional outcomes. Materials/Methods: 4597 patients who underwent PT for low back pain were identified from the registry of a commercial physical therapy organization. The primary outcome measures were pre- and post-treatment scores on the Oswestry Disability Index (ODI), activity Numeric Pain Rating Scale (NPRS), and resting NPRS. Previously published thresholds for minimum clinical important difference (MCID) were used to determine the proportion of patients meeting MCID for each of our outcomes. Logistic regression analysis was used to determine risk factors predictive of treatment failure. Results: The average number of visits was 14 and average duration of therapy was 45 days. Treated diagnoses included lumbar sprain, lumbar disc displacement, lumbosacral spondylosis, and lumbago. 28.5% of patients met the MCID for improvement in ODI. Night symptoms, obesity, and smoking were predictors of treatment failure for ODI. 59% of patients met the MCID for improvement in resting NPRS, with history of venous thromboembolism, night symptoms, psychiatric disease, workers’ compensation status, smoking, and obesity predictive of treatment failure. 60% of patients met the MCID for improvement in activity NPRS, with night symptoms, workers’ compensation status, and smoking predictive of treatment failure. Discussion/Conclusion: The treatment of low back pain continues to be challenging. 40-72.5% of the population did not meet MCID for pain and function following treatment of low back pain with PT. Common risk factors for treatment failure included smoking, workers’ compensation, night pain, and psychiatric history. Though PT offers low risk when compared to more invasive treatments of low back pain, further study on the clinical and cost effectiveness of PT for common low back pain diagnoses is needed.