Gripping device for tensile testing of small animal ligaments

TESTING isolated knee ligaments from small laboratory animals in tension is exceedingly difficult due to problems in gripping the specimen. Standard engineering technology does not adequately cater for the small size of the specimen, its slippery nature and ease of compressibility within grip faces. To overcome these limitations investigators (TIPTON et al., 1967; Vm)IK, t968) have commonly used femur-ligament-tibia preparations. Tensile tests of such preparations give information on the weakest link in the functional complex, which in the case of rats is often at the site of the epiphyseal plate. In an attempt to obtain failure of the ligament itself, rather than separation at the epiphyseal plate, a new method of gripping boneligament-bone preparations was developed which represents a modification of the design used by Rundgren in 1974. Knowledge of the tensile strength of the ligament provided an opportunity to investigate changes in the structure and mechanical properties o.f ligamentous tissue following different treatment programs with more validity.