Reaction Force Magnitude and Orientation During Supine Thoracic Spine Thrust Manipulation: An Exploratory Analysis and Reliability of Preload and Impulse Phase.

Objective: The main purpose of this study was to explore specific kinetic parameters during supine thoracic thrust manipulation and to analyze task reliability and differences between various practitioners METHODS: Kinetic parameters were assessed by examining ground reaction force magnitude and orientation (on the basis of the zenithal angle) using force platforms. The manipulative procedure (consisting of the application of 3 preloads followed by 1 single thrust adjustment) was performed by different practitioners at 3 sessions. Application of thrust was allowed for trained practitioners only. Preload force, peak force, and vector force orientation were compared between sessions and practitioners.

Results: Reliability analysis showed that practitioners achieved similar preload and peak force independent of the session, with comparable force orientation data. Differences between practitioners were observed for preload and peak force but not regarding the zenithal angle during the thrust phase.

Conclusion: This study is the first that explores kinetic parameters for supine thoracic thrust manipulation. Task repeatability was confirmed and several differences were observed between practitioners. Certainly, there is a need for further investigation examining both dynamic parameters (ie, velocity and accelerations) and the potential neurologic effect of such manipulative technique.