Variability of Trunk Movement

As a part of a larger project we are looking at the variability of movement and in particular of the trunk. The movement that we are measuring is a hand reach from anterior at hip height to posterior overhead. We have subjects performing these reaches under different conditions. The picture below is showing one subject while reaching posterior overhead.

Posterior reach

We now have data for 24 subjects. Our initial analysis is showing highly individual strategies for the different conditions. This is exactly what we observe clinically. I have attached a graph showing exactly this. Here is one individual who is showing little variability in performing the movement in both the sagittal (top graph) and transverse plane (bottom graph). There is much greater variability observed in the frontal plane (middle graph).

Graph posterir reach

There are a number of interpretations that can be used as to why this individual is choosing this particular strategy. This is something that we will present at a later time. The vertical line in the graph is showing where in the movement, position, the subject is in the picture. The analysis tool Visual 3D ( is utilized to analyze our data and also provides these great images.

As soon as we have more results and publications we will share this with you.

Jessica, Ali and Ola