Abstract
Migration of the humeral component of the surface elbow arthroplasty has been reported as one of major long-term complications with it. We have attempted to overcome this problem by using a wider component. This study compares the differences of magnitude and direction of migration using the wide and the standard components.
Humeral components (Design A: 40 mm in width, Design B: 25mm in width) were attached to humeral models made of polyurethane foam. Each model was then statically loaded both longitudinally and perpendicularly to the distal axis of the model.
The average maximum loads shown by stress-strain curves with longitudinal loading were 77.2 kgf with Design A and 39.6 kgf with Design B (p<0 .01) . With perpendicular loading, they were 11.8 kgf for Design A and 8.8 kgf for Design B (p<0 .05) .
From the biomechanical point of view, the migration of the Design A type should be less than that of the Design B. Not only can the force distribution be reduced by the wider component, but also the Design A type is supported by both the medial and lateral supracondylar columns, while the Design B is supported only by the medial column.
