The Effect of Augmented Feedback and Expertise on Spinal Manipulation Skills: An Experimental Study

The purpose of this study was to investigate the combined effect of augmented feedback and expertise on the performance and retention of basic motor learning spinal manipulation skills. A total of 103 chiropractic students with various training expertise were recruited for the study. Participants were evaluated at baseline, immediately after trials of augmented feedback practice and 1 week later. During all 3 assessments, students were asked to perform several trials of the same spinal manipulation, for which the maximum preload force, onset of thrust, thrust duration, force and peak force, thrust duration, rate of force application, and any drop in preload force were calculated. The constant error, absolute error, and variable error were calculated for the 3 experimental blocks of trials. Results confirmed that augmented feedback training modified several biomechanical parameters such as the rate of force application, the preload force, and the drop in preload force. The study also confirmed that many biomechanical parameters, including thrust duration and rate of force application, are modified with expertise but failed to identify any interaction effect between expertise and augmented feedback training effects. The study determined that expertise did not influence how students performed after a session of augmented feedback training. The study also determined that augmented feedback related to the global performance can yield improvements in several basic components of the spinal manipulation task. These results should be interpreted considering basic motor learning principles and specific learning environments.