Is age or speed the predominant factor in the development of trunk movement in normally developing children?

Gait analysis is an increasingly used tool in the evaluation of neurological or orthopaedic problems in children. A good insight into age-related changes in normal paediatric gait is necessary to evaluate gait inefficiency caused by pathological walking patterns in children. However, no systematic evaluation of the normal development of trunk movement has yet been made.

Data of n=85 healthy children were available. They were asked to walk at self selected speed. The gait data were measured with the Vicon Plug-In-Gait model, including the trunk. We assessed gait cycles of thorax, spine and pelvis in the sagittal, frontal and transverse plane, respectively, stratified by age (categories: <4, 4-6, 7-9, 10-12 and 13-16 years) as well as by normalized speed (≤ 0.40, 0.41-0.49, ≥ 0.50).

The sagittal thorax and spine movement was found to be gradually and significantly associated with age, but less so with speed, indicating that, with increasing age, children tend to lean their trunk forward relative to both the global co-ordinate system and the pelvis. In contrast, the frontal and transverse parameters of spine and pelvic movement seemed to depend mainly on speed, not age.

Our study shows that age dependency has to be considered with respect to sagittal thorax and spine movements. This finding might be of great importance with respect to the identification of pathological patterns in trunk movement.