09/29/2026
Just Published: New Research Shows WHERE You Point the Impulse Matters — A Lot
We are excited to share that a new peer-reviewed study from Dr. Chris Colloca and our research team has just been published in the Journal of Manipulative and Physiological Therapeutics (JMPT) — one of chiropractic's most respected scientific journals.
Here is what the study found — in plain English.
──────────────────────────────
WHAT WE STUDIED
──────────────────────────────We asked a simple but clinically important question: Does the direction you angle the Impulse instrument when you deliver a thrust actually change what happens in the spine?
To answer this, we used a highly controlled animal model (sheep spines, which are well-validated as anatomically comparable to human lumbar spines) and measured real vertebral movement using sensors surgically attached directly to the spinal bones. We tested three angles:
• 90° — straight posteroanterior (the classic PA thrust)
• 60° — angled toward the head (cephalad)
• 120° — angled toward the feet (caudal)
We delivered 13 thrusts at each angle, in randomized order, across 12 animals — a total of over 468 individual thrust events — and measured the acceleration response at both the contact vertebra and the adjacent levels above and below.
──────────────────────────────
WHAT WE FOUND
──────────────────────────────
The angle of application made a statistically significant difference — and the results were striking:
✦ CAUDAL (120°) THRUSTS produced the GREATEST vertebral accelerations at every spinal level measured. The differences were not subtle: mean accelerations for caudal thrusts were 74.9 m/s² at L2, 79.9 m/s² at L4, and 109.0 m/s² at the combined L2–L4 level — significantly greater than both the PA and cephalad conditions (P < .01).
✦ THE DIRECTION OF THRUST DETERMINED WHERE THE ENERGY WENT. Cephalad thrusts moved energy upward (greater response at the vertebra above the contact point). Caudal thrusts moved energy downward (greater response at the vertebra below). In other words, the spine responded in the same direction you pushed — every time.
✦ THE STANDARD 90° PA THRUST WAS NOT THE MOST EFFECTIVE angle in this model. This challenges the long-held assumption that perpendicular thrusts are always optimal.
──────────────────────────────
WHY THIS MATTERS TO YOUR PRACTICE
──────────────────────────────
Chiropractic technique has always taught that your line of drive matters. This research now provides direct biomechanical evidence for exactly that principle:
• The angle you choose is not just a stylistic preference — it changes the biomechanical outcome at the level you are treating and at adjacent levels.
• If your clinical goal is to target a specific segment above or below the contact point, this research suggests that angling your thrust in that direction may amplify the response at your intended target.
• The finding that caudal thrusts produced the greatest overall vertebral accelerations in this model is consistent with the facet joint geometry of the lumbar spine. Your line of drive interacts directly with spinal anatomy.
This is why we have always believed that instrument-assisted adjusting is not simply about delivering force — it is about delivering force with precision: the right amount, at the right location, at the right angle.
──────────────────────────────
READ THE FULL STUDY
──────────────────────────────
Colloca CJ, Kosmopoulos V, Gunzburg R. Effect of applied spinal manipulation force direction on vertebral accelerations: An in vivo ovine study. J Manip Physiol Ther. 2026;49:eJMPT-D-26-00008.
https://doi.org/10.67400/JMPT-D-26-00008
The article is open access — free to read, download, and share.
We are extremely grateful for the support of the International Spine Research (INSPIRE) Foundation, The Dr. William M. Harris Family Foundation, and CBP Nonprofit, Inc. for their support of this research.
