Abstract
[Purpose] We studied the effects of active exercise on preventing joint contractures secondary to joint immobilization in a functional position. [Subjects and Methods] Twelve female Wistar rats were used. The unilateral ankle joint of each animal was immobilized in a functional position by a cast for a duration of seven days. In the active exercise group, the casts were removed during treadmill running (20 min) once a day. In the control group, the casts were changed once a day. On the first and last days, the ranges of motion (ROM) of the ankle joints were measured. [Results] The ROMs were 117.3 ± 6.1° in the immobilized group and 119.7 ± 5.3° in the active exercise group on the first day with no significant difference between the two groups. The ROMs were 84.0 ± 4.6° in the immobilized group and 93.3 ± 8.0° in the active exercise group on the last day. ROM had decreased not only in the immobilized group but also in the active exercise group. The ROM of the active exercise group had significantly increased on the last day. [Conclusion] The fixation conditions described above could not prevent joint contracture.
