Which Reference Line Describes Head Position Best?
Anne-Louise Haas*, Katrin Bracht, Thomas Stöggl and Reinald Brunner
University Children’s Hospital Basel, Laboratory of Movement Analysis, Switzerland
- *Corresponding Author:
- Anne-Louise Haas
Physiotherapist, University Children’s Hospital Basel
Laboratory of Movement Analysis, Spitalstrasse 33
Basel, 4056, Switzerland
E-mail: [email protected]
Received date: April 28, 2016; Accepted date: May 13, 2016; Published date: May 20, 2016
Citation: Haas AL, Bracht K, Stöggl T, Brunner R (2016) Which Reference Line Describes Head Position Best?. Physiother Rehabil 1:110. doi:10.4172/2573-0312.1000110
Copyright: © 2016 Haas AL, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background and Purpose: It is generally assumed that the head is positioned on the body plumb line. The reference line defined by Kendall (KL) (1952, Kendall et al. 2005) is the most citied one. We hypothesized that the head is held anteriorly to the KL and the gravity line (GL) derived from the center of mass (CoM). The purpose of the study was to objectively assess the relation between head position and GL / KL in the sagittal plane using a 3d-tool to define the CoM. Methods: Head center (HC) and CoM were calculated in 30 normal subjects (25-35 years) while standing using a three dimensional motion analysis system. The distance from the GL (defined by the CoM) and KL (two cm in front of the lateral malleolus) to the HC was calculated. Results: All 30 subjects held their HC anterior to the KL. The HC was anterior to the GL in 11 subjects, through the GL in four and posterior to the GL in 15. Conclusion: According to this study the two references lines cannot be considered the same, suggesting that previous assumptions about this relationship may be inaccurate. KL was not discriminative in our subjects for HC position.