Rotator cuff tests on intact goat model

Abstract

The project is to design a fixture for testing the behaviour of rotator cuff using a goat

model.

In ten fresh goat shoulders, all soft tissues were removed from the proximal humerus,

leaving the infraspinatus tendon intact with attached scapula. The infraspinatus tendons

of the goat are similar to those of the human rotator cuff in size, shape and

microstructure. The specimen was clamped onto a custom-designed fixture with

shoulder abduction at 60°. A preload of 20 N was set at the crosshead of the testing

machine. Fifty cycles with tensile loads of 75 N were then applied with a crosshead

extension rate of 20 mm per minute. Incremental cyclic loading of 25 N per fifty cycles

were applied until failure.

The results showed that the incremental deformation ranged from 25mm to 48 mm with

loads reaching up to 425 N.