Impairment-Based Versus Classification-Based Physical Therapy for Acute and Subacute Low Back Pain: a Randomized Controlled Trial

PURPOSE: The purpose of this study is to describe a multimodal impairment-based clinical model for the treatment of low back pain utilizing the concept of Regional Interdependence (Wainner et al 2007) and to determine the relative effectiveness of this model versus classification-based therapy using the Treatment-Based Classification System for acute and subacute low back pain (Delitto et al 1995, Fritz et al 2006, Fritz et al 2007) in terms of improvements in pain and disability at 4 weeks and 6 months.

BACKGROUND: Recent studies have shown that subclassifying patients with low back pain into treatment groups results in better outcomes than treating all patients with low back pain as homogenous groups. (Fritz et al 2003) However, no studies have directly compared the efficacy of impairment-based versus classification-based physical therapy for patients with acute and subacute low back pain.

HYPOTHESIS: We suspect that both methods of treatment will be effective, but we are uncertain if one will be more effective than the other. Therefore, our null hypothesis will be that both methods will be equally effective.

METHODS:

1. Patients referred to physical therapy at Hendricks Regional Health in Plainfield, IN will be screened for eligibility. Eligible participants will be offered the opportunity to voluntarily participate in the research study. Those patients who are both eligible and interested will receive an informed consent form approved by the Hendricks Regional Health Institutional Review Board.
2. All subjects will complete a standard intake form and self-report measures. The principal investigator will obtain a subjective history from the patient and perform a standardized baseline physical examination.
3. After the baseline examination, subjects will be randomized in blocks of 4, 6, or 8 using a concealed, computer-generated randomization sequence accessed electronically through a Microsoft Excel spreadsheet using the VLOOKUP function to return the group assignment when the subject number is entered.
4. All subjects in both groups will be treated by the principal investigator two times per week for two weeks followed by once per week for two weeks (total of 6 visits) regardless of treatment group assignment. All subjects will receive standardized education as well as additional individualized education as deemed appropriate by the treating clinician. Subjects will be given a home exercise program consisting of the same exercises they performed in physical therapy and asked to perform their exercises twice per day.
5. Patients in the impairment-based group will be treated using a multi-modal treatment approach utilizing manual therapy of the thoracolumbosacral spine and hip as well as motor control exercises. Patients in the classification-based group will be categorized into subgroups according to the previously described Treatment-Based Classification (TBC) Algorithm and treated accordingly.
6. After completion of the 6 visits, we intend to discharge most patients to a home exercise program. However, patients who require more or fewer visits than this will still be included in the intention-to-treat analysis. Patients will be encouraged to perform their home exercises at least 3 times per week until the 6 month follow up.
7. Primary and secondary outcome measures will be collected at 4 weeks and 6 months from baseline.