Biomechanical Properties and Behaviours of the Wrist Joint - Computational Biomechanics of the Wrist Joint - page 13

Chapter 2
Biomechanical Properties and Behaviours
of the Wrist Joint
Abstract Previous experimental and computational studies have outlined several
properties and behaviours of the wrist joint. This chapter compiled relevance
inputs associated with the biomechanical considerations of the joint, consisting of
contact analyses at the articulations and load transmission throughout the joint.
The succeeding sections present information on the biomechanical properties of
the cartilages and ligamentous structure. It was addressed that due to difficulties in
accessing the articulations in the wrist joint, investigations on the articular carti-
lages were mainly done through computer simulations. For the ligaments, a typical
stress strain curve was used to mimic its mechanical behaviour. The principal load
behaviour of ligaments with respect to their elongation during constant elongation-
rate has evident the existence of the toe-regions, thus addressing its viscoelastic
behaviour. Information on current methods in biomechanical modelling—rigid
body spring and finite element—is also presented. Greater emphasize was given to
the finite element method due to its appropriateness in performing contact analysis
in the wrist joint. Facts and findings from previous finite element studies were
included to support future understanding.
Keywords Load transfer Contact surface Viscoelastic Stress-strain curve
Rigid body spring Finite element
2.1 Contact Surfaces and Load Transmission
The application of pressure sensitive films to investigate the articulating surface
loads transmission of the wrist joint has proved to be possible based on several
previous experimental works. However, not all of the articulations could be
inserted by films attributed to relatively smaller gaps compared with the thickness