How pain can alter motor (movement) programs


Pain, injury and inflammation can result in immediate and often dramatic changes in movement programs that is when and how much muscles contract, co-activate, coordinate relax and recruit.

I once had a patient who was salsa dancing and suddenly his back became immobilized and he was unable to move normally. He said his fellow dancers thought that he was joking. He was not joking.

Chiropractic adjustments improve smoothness of lumbar (lower back) spinal motion, acceleration, and angular velocity.

Lumbar motion changes in chronic low back pain patients.

Mieritz RM, DC, PhD, Bronfort G, DC, PhD et al. Spine Journal 2014

Comments: This 2014 paper uses a “high tech” equipment (Spine Motion Analyzer) to quantify not only the overall range of motion (ROM), but the quality of motion based on angular velocity, acceleration, & smoothness of motion (aka jerk index) which is based on the number of changes in acceleration throughout a particular ROM. The results document that chiropractic adjustments improved all measurements of improved quality of motion, but several exercise programs which were also evaluated improved only half of the measurements. Importantly, this study is the first to document that chiropractic adjustments improved smoothness of motion but the exercises did not. The paper notes that simply measuring end range of motion and not quality of motion is not sensitive enough to detect important clinical improvements of motion that occur with chiropractic adjustments. 

Methods: This study assesses changes in lumbar regional motion in 199 Low Back Pain (LBP)Patients (>6 weeks to 12 weeks) with (w) or w/o leg pain &/or neurological signs (18-65 yrs) over 12 weeks of care. Lumbar spine kinematics were determined using a high tech instrumented spatial linkage system (CA 6000 Spine Motion Analyzer; OSI, Union City, CA, USA) to measure angular velocity, acceleration & smoothness of motion at 2 pre-treatment visits & 1 follow up visit after 12 weeks of treatment. ‘Low tech’ ROM measurements describe functional range but little about the quality of the motion. Simple ROM has limited use as a measure of treatment outcomes or as a stand-alone measure of disability. Addressing the patterns & quality of the motion rather than just the end ROM may be more responsive measures. ‘High tech’ 3D spinal motion analysis may aid in describing patient movement & changes with various treatments & remedy deficiencies in the quantification of LBP impairment. 

The lumbar region spinal motion data were analyzed relative to 3 treatment modalities: 

  1. High-dose, supervised exercise (20 supervised sessions of high reps of core exercises)
  2. Low-tech trunk exercise (2 supervised sessions w PT training & advice & then exercise on their own)
  3. Spinal Manipulation (SM) (2 visits/wk for 12 wks of HVLA side-posture).

Results: Lumbar region motion parameters were altered over 12 weeks in all groups, but only the chiropractic spinal manipulation group changed significantly in all outcomes, and the exercise groups in half of the motion parameters analyzed. Spinal Manipulation group changed to a smoother motion pattern of motion but the exercise groups did not. The hypothesis that LBP Patients would move more smoothly after Spinal Manipulation was confirmed. 

Conclusion: This study provides evidence that spinal motion changes can occur in CLBP Patients over a 12-week period and that these changes are associated with the type of Treatment.