This study was aimed at evaluating the effects of neuromuscular electrical stimulation (NMES) of low frequency on the vastus lateralis muscle. Eleven dogs were randomly placed in 3 groups: I (control), II (NMES post immobilization), and III (NMES during and post immobilization). The right femoral-tibial-patellar joint was immobilized for 30 days by the percutaneous transfixation type II method. The dogs from group III were placed on electrotherapy 3 times a week during (30 days) and post-immobilization (60 days) and the dogs from group II post-removal of the temporary rigid immobilization. The parameters evaluated consisted of: measurement of thigh circumference, joint motion using a goniometer, gait analysis, creatine kinase (CK) and aspartate aminotransferase (AST) levels and morphometry of the longitudinal muscle fibers of vastus lateralis muscle. The gait analysis was performed daily and the circumference of the thigh, joint motion, and muscle biopsy were performed on days 0, 30, 60 and 90 post-immobilization. The blood samples for CK and AST were collected before and immediately after 6, 24 and 48 hours post-NMES on days 0, 1, 7, 30, 45, 60, 75 and 90. The NMES was employed on the femoral quadriceps muscle group with a frequency of 50Hz post-duration of 300msec on an on-time/off-time ratio of 1:2. There was no significant difference on the gait analysis, thigh circumference, joint motion, and CK and AST values. The greatest hypertrophy change was observed on longitudinal fibers of the dogs from group II (P=0.0005), followed by the dogs from group III. NMES of low frequency causes hypertrophy of the vastus lateralis muscle in dogs post-temporary immobilization of the stifle joint, recommending its use in animals with muscular atrophy.
dogs; immobilization; hypertrophy; muscle; rehabilitation
