Use of Isokinetic Dynamometry to Assess Muscle Function in Burned Patients Is A Reliable Tool to Assist Progressive Resistance Exercise Prescription

Isokinetic dynamometry is used during exercise testing and rehabilitation to obtain a quantitative strength measurement on which progressive strength training programs can be based. This study assesses the test-retest reliability of isokinetic leg function in the knee flexors and extensors at 150°/s in children and young adults with severe burns to be used for rehabilitation exercise program prescription. In 39 severely burned patients (49 ± 14% total body surface area burn [TBSA], mean ± SD; 34 ± 21% TBSA 3rd degree; 14 ± 5 years, 153.3 ± 16.5 cm height; 53.8 ± 17.9 kg) knee flexion/extension isokinetic dynamometry at 150°/s was performed on each patient's dominant leg in two sessions. The patient was acquainted with the test and performed 1 set of 10 repetitions at 150°/s. A second session of 1 set of 10 repetitions at 150°/ was performed within 24 h of the first. Muscle function outcomes were knee flexion/extension peak torque, average peak torque, and average power. One-sample paired t tests were performed for all muscle function outcomes; intraclass correlation coefficients and r2 values with session two as a function of session one were calculated. Sessions did not differ significantly in knee extension or flexion for any muscle function outcome or the hamstrings to quadriceps ratio. All intraclass correlation coefficients were >0.89 and r2 > 0.79. Test-retest isokinetic dynamometry functional measurements in the knee flexors and extensors at 150°/s are reliable in the burn population and may aid resistance rehabilitation program prescriptions.