Optimization of Spinal Manipulative Therapy Protocols

Research on spinal manipulative therapy for individuals with low back pain has been hampered by a lack of understanding of which of the physiologic effects produced by spinal manipulation are related to clinical benefit, and how these effects can be used to optimize treatment outcomes. Prior research has identified physiologic effects that relate to the clinical benefits from spinal manipulation treatment. The goal of this project is to examine strategies to use these effects to identify optimized treatment protocols. The results of this project will provide critical information for future clinical trials related to spinal manipulation.

Low back pain (LBP) is a common and costly condition. Spinal manipulative therapy (SMT) is a common mind body intervention for individuals with LBP. Although SMT for LBP has been examined in numerous clinical studies, the literature on SMT remains unclear and even contradictory as to the effectiveness of this treatment. Studies that have supported SMT have generally found relatively small treatment effects. Many reasons have been offered for the inconsistent research literature and small effect sizes of SMT. A primary rationale offered is that the SMT protocols used in clinical research are not optimal, primarily due to a lack of understanding of the underlying mechanisms explaining the clinical benefits of SMT realized by some patients with LBP.

The prior work of this research team has identified two mechanisms explaining the therapeutic effects of SMT. These effects are a reduction in spinal stiffness and improved activation of the lumbar multifidus muscle. This research has also developed accurate, non-invasive methods to measure these effects and their response to SMT. The model identifying these two mechanisms has been validated in a second patient sample.

The overall goal of this proposal is to optimize SMT treatment protocols for patients with LBP. The optimization strategy in this study will evaluate SMT combined with other treatments known to modulate the same signals that underlie the clinical effects of SMT assessing both mechanistic (stiffness, lumbar multifidus activation) and patient-centered (function and pain) outcomes. This project will use innovative methodology to efficiently evaluate the effects of various individual treatment components towards an overall effect; identifying which components are contributing to the target outcomes and which, if any, may be discarded. All participants will be provided 2 sessions of SMT, and then will be randomized to a treatment group for an additional 3 weeks using a factorial design and stratified by responder status in order to evaluate different combinations of intervention components (muscle activation exercise, spinal mobilizing exercise, additional SMT) that work on the same pathways that modulate the same effects (spinal stiffness and muscle activation). Outcomes will include spinal stiffness and muscle activation measures as well as patient-reported outcomes assessed at baseline, and after 1 week, 4 weeks and 3 months. Results of this project will provide optimized SMT protocols that will be ready for application in future randomized controlled trials examining the efficacy and effectiveness of SMT.

Eligibility Criteria:
Inclusion Criteria:

I. Pain between the 12th rib and buttocks with or without symptoms into one or both legs, which, in the opinion of the examiner, originate from the lumbar region.

II. Age 18 - 60 years

III. Oswestry disability score \> 20%

Exclusion Criteria:

I. Prior surgery to the lumbosacral spine

II. Currently pregnant

III. Currently receiving mind-body or exercise treatment for LBP from a healthcare provider (e.g., chiropractic, physical therapy, massage therapy, etc.)

IV. Neurogenic signs including any of the following: positive ipsi- or contra-lateral straight leg raise test; reflex, sensory, or strength deficit in a pattern consistent with lumbar nerve root compression