Background
As a common clinical disease, the incidence of joint contracture which is characterized by the reduction of range of motion (ROM) in the active or passive state of the joint has increased in recent years. This study was to investigate the effects of ultrashort wave on joint dysfunction and muscle atrophy in a rabbit model of extending knee joint contracture and its mechanism.
Methods
35 rabbits underwent unilateral immobilization of a knee joint at full extension to cause joint contracture, and 5 rabbits were used for the control group. After 8 weeks immobilization, 35 rabbits were randomly divided into the following seven groups: I-8, R-1, R-2, R-4, T-1, T-2, and T-4. In the Group R-1, R-2 and R-4, the rabbits were experienced one, two, and four weeks self-recovery. In the Group T-1, T-2, and T-4, the rabbits were experienced one, two, and four weeks ultrashort wave treatment. The effect of self-recovery and ultrashort wave treatment on joint dysfunction and muscle atrophy was assessed by measuring the degree of total and myogenic contracture, evaluating the cross-sectional area (CSA) of rectus femoris and assessing the protein levels for MyoD.
Results
A tendency toward reduced the degree of total and myogenic contracture was observed after self-recovery and ultrashort wave treatment. A tendency toward increased the CSA of rectus femoris and the protein levels for MyoD was observed after self-recovery and ultrashort wave treatment. The ultrashort wave treatment led a better efficacy than self-recovery against the total and the myogenic contracture, the CSA and the protein levels for MyoD of rectus femoris.
Conclusions
Ultrashort wave ameliorates joint dysfunction and muscle atrophy via upregulating the expression of MyoD protein in a rabbit model of extending knee joint contracture.