3D biomechanical model of the thumb carpo-metacarpal joint
3D biomechanical model of the carpo-metacarpal joint of the thumb
IntroductionOf all hand joints, the thumb carpo-metacarpal (CMC1) joint is the most vulnerable to degeneration by use, possibly ultimately requiring surgical intervention. This is a significant problem in an aging population. CMC1 vulnerability may relate to the recent evolutionary development of a fully opposable thumb unique to the human species, in which the CMC1 is key. The CMC1 is a saddle joint, and as such has a highly specific set of ligaments. However, the function and structure of these ligaments are still under debate. Also clinically, it has not been well established what harmful joint loads may result from failure of (one of) the ligaments by trauma or degenerative disease.
ObjectivesThe objective is to improve understanding of the CMC1 ligament structure. To this end, ligaments in five anatomic specimens will be investigated and reconstructed in a 3D computer model. By motion tracking, the CMC1 joint motion envelop and centers of rotation will be determined. The bone geometries will be reconstructed from CT scans that will include the marker frame pins so that joint motions can be accurately reconstructed. By dissection, the CMC1 ligaments will be identified and measured, and mapped onto the 3D model. The congruence of the reconstructed ligaments with the experimentally measured motion will be used for refinement of the anatomic mapping. The resulting models will be used in future studies of CMC1 loads with normal and defective ligaments.
Collaborating institutes Depts. of Anatomy and Biomedical Engineering (IBiTech) of UGent.