Effect of low-intensity therapeutic sonication on the healing and ultrastructure of transected medial collateral ligament (MCL) in rabbits

This study was conducted to determine the effect of low intensity continuous sonication on the biomechanical properties and ultrastructure of experimentally transected and repaired medial collateral ligaments (MCL) in 28 rabbits. Twelve rabbits were randomly assigned to each of the control and experimental group. The right hindlimb of all the rabbits were immobilized for one day only. The experimental group ligaments were sonicated in continuous waves at a space-averaged intensity of 0.5 W/cm;The results showed that the two groups differed significantly only on initial body weight (P =.011). However, a one-way analysis of covariance indicated that initial body weight was not related significantly to any of the dependent variables and did not act as a suppressor variable.;Even though the experimental group (right) ligaments showed higher mean values in their tensile strength: (22.42 ;The results of ultrastructural analysis showed that sonication induced the development of an extensive network of rough endoplasmic reticulum (rER) indicative of rapid protein synthesis. It also induced the appearance of intracytoplasmic collagen fibrils indicative of rapid collagen turnover.;In conclusion, the researcher suggests that sonication may have some merit in clinical application in the management of ligamentous ruptures after surgery, especially when used as an adjunctive tool to early functional rehabilitation and exercise.