Optimization of Spinal Manipulative Therapy Protocols

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.

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