SIMULATING LIGAMENT INJURY OR LAXITY

摘要

Experimental studies of joint kinematics and kinetics are often conducted so as to determine a population trend, such as characterizing the net loading patterns across a joint for a given activity. Typically there are wide variations in the measurements made between subjects. Studies that examine the differences between subjects and how those differences relate to the variations in measurements are important for clinical decision making, as in determining which diagnostic examinations reveal a pathologic condition. In the area of joint motion, the degree of injury or laxity in the ligamentous tissues is strongly correlated to kinematic measures. Experimental studies of this kind could be improved if there were a reliable way to simulate varying degrees of ligament injury or laxity. A study was undertaken to create varying degrees of ligament injury without cutting the tissue. Instead the ligaments were individually stretched. Initial experiments were conducted on rats, and later experiments on goats. The ligaments were exposed via incision, and marked with Verhoff's stain dots. The tissue was then stretched to varying amounts with either force control or displacement control, and the changes in length measured. The stretching under force control was superior to a displacement control method.