Investigation of reaction force magnitude and orientation during supine thoracic thrust manipulation applied to intervertebral and costovertebral regions.

BACKGROUND

Spinal manipulative techniques are commonly used in manual therapies but quantified descriptive and reliability data are lacking considering supine thoracic thrust manipulation.

OBJECTIVES

The purpose of this study is to explore and compare kinetic parameters during supine thoracic thrust manipulation performed at two different thoracic regions. Intra-rater task repeatability and influence of practitioners were estimated.

DESIGN

Exploratory and agreement study.

METHODS

Kinetic parameters were assessed by examining reaction force magnitude and orientation (on the basis of the zenithal angle) using force platforms. Manipulative procedure (consisting in the application of 3 preloads followed by one thrust adjustment) at both intervertebral and costovertebral region was performed by different practitioners at three sessions. Application of thrust was allowed for experienced practitioners only. Preload force, peak force magnitude and vector force orientation were compared between anatomical sites, sessions and practitioners, and bias with limit of agreement were estimated.

RESULTS

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

CONCLUSIONS

The present study is the first that explores kinetic parameters for supine thoracic thrust manipulation applied on two different regions of the thorax. Results confirm consistency of performance among practitioners for supine manipulative techniques at intervertebral and costovertebral region. While task repeatability was confirmed, several differences were observed between practitioners. Further investigations would examine velocity, acceleration and potential neurophysiological effect of such manipulative technique.