In this section
@inproceedings{Amadi:2006,
author = {Amadi, HO and Bull, AMJ and Hansen, UN},
pages = {S496--S496},
publisher = {Journal of Biomechanics},
title = {A resultant force and limiting ligament strains approach to computing glenohumeral joint translations},
year = {2006}
}
TY - CPAPER
AB - The aims of this study were (1) to create a tool to investigate the loading of the intracapsular ligaments of the GHJ during shoulder movement, and (2) to investigate how the humeral head may need to translate to minimise ligament overstraining.Imaging datasets were used to create surface geometries of the GHJ. A joint coordinate system (JCS) was applied for kinematics description1. Five ligaments were modelled with literature-provided properties and insertions2,3. An algorithm was developed to relate clinical shoulder position data to the JCS. Ligament paths were modelled as a straight line from glenoid to humeral insertion with spherical wrapping on the humeral head adjusted according to the actual surface contour. These were used to quantify a resultant effect of the ligament loading. Physiological kinematics data during passive clinical examinations of the arm4 were applied to the model. In order to limit the overstraining of the ligaments, translations were imposed on these kinematics data in the direction of the resultant forces due to the ligaments. These translation were limited when the ligament strains were below an experimentally-derived physiological threshold2,3. Individual ligament loads of up to 290 N were predicted during impingement test kinematics when translations were not taken into account. This same movement resulted in a computed 3.1 mm anteroinferior translation of the humeral head when limiting ligament strains. There were no predicted translations for pure abduction and forward flexion without humeral axial rotation.There is currently no direct measure of translations of the shoulder that can be applied clinically. This work is a novel method that allows the relative ligament restraints during physiological motion to be calculated taking into account possible GHJ translations. This can be applied in guiding clinical kinematics tests, as well as surgical interventions.1Wu et al, J Biomech, 20052Boardman et al, J Should Elb Surg, 19963Biglian
AU - Amadi,HO
AU - Bull,AMJ
AU - Hansen,UN
EP - 496
PB - Journal of Biomechanics
PY - 2006///
SP - 496
TI - A resultant force and limiting ligament strains approach to computing glenohumeral joint translations
ER -
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