The Effect of Chiropractic Adjustments on Movement Time: A Pilot Study Using Fitts Law



      To investigate the effect of chiropractic adjustments on movement time using Fitts Law.


      This was a prospective, randomized controlled trial. Ten patients from a private chiropractic practice participated. Participants in the treatment group received high-velocity, low-amplitude chiropractic adjustments to areas of joint dysfunction (chiropractic subluxation). A nonintervention group was used to control for improvement resulting from time and practice effects.
      Movement time was measured as participants moved a cursor onto a target appearing on a computer screen. A range of target widths and target distances were used to vary the index of difficulty.


      All participants in the experimental group had significantly improved movement times following spinal adjustments compared with only 1 participant in the control group. The average improvement in movement time for the experimental group was 183 ms, a 9.2% improvement, whereas the average improvement in movement time for the control group was 29 ms, a 1.7% improvement. The difference (improvement) scores after the intervention were significantly greater for the chiropractic group compared with the control group as measured by a 2-tailed independent samples t test (P < .05).


      The results of this study demonstrated a significant improvement in movement time with chiropractic care. These results suggest that spinal adjustments may influence motor behavior.

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