Early Rehabilitation with Exergame - Which Muscle Groups are Addressed by Bedside-Based Knee Exercises?

BACKGROUND: Knee exercises are generally recommended following knee-related operations. Nevertheless, compliance in performing self-administered exercises is varying. The use of exergames may alter patient compliance. These computer games encourage the user to exercise. Exergames are not yet used much in orthopedic rehabilitation. The aim of this study was to analyze the influence of different seating positions in electromyography while performing knee exercises with the exergame GenuSport. MATERIAL AND METHODS: 72 healthy women and men were tested in 6 seating positions using an application-based knee-training device (KT). Positions were 1. user seated 90 upright with straight leg on KT, 2. 90 upright with leg exercising in external rotation on KT, 3. 90 upright with leg exercising in internal rotation on KT, 4. 90 upright with straight leg on 30mm elevated KT, 5. 45 upright with straight leg on KT and 6. 45 upright with straight leg on 30mm elevated KT. Electromyogram was recorded for biceps femoris, rectus femoris, semitendinosus, vastus medialis, adductor magnus and vastus lateralis. RESULTS: No significant difference was shown in position 2, 3 or 4 compared to position 1. In position 5 and 6, EMG reported significantly higher values compared to positions 1 to 4 (ischiocrural: 130% and quadriceps: 90%). The quadriceps was activated significantly less in position 6 compared to 5. CONCLUSION: 1. Bedside-based knee extension exercises are most effective in a seated position of 45 trunk inclination. 2. A slightly more bent knee (KT elevation of 30mm) leads to a higher activation of the ischiocrural muscles.

The determination of the validity of an application-based knee-training device.

The goals of knee rehabilitation are to improve range of motion and muscle status. The aim of the study was to investigate accuracy and reproducibility of a newly designed knee-training device (KT) under standardized laboratory conditions.Two application-based software programs, one to measure maximum force and the other intended to improve users' coordination were developed to be used on a tablet during exercises, wirelessly connected to KT placed under the popliteal fossa.KT was loaded for 20 intervals of 15 seconds (s) ranging between 0-350 Newton (N) each. The interval of times was chosen to be enough to take right measurement for accurate results. In addition, a 300-s continuous measurement was undertaken. The pressure readings were developed through a servo-hydraulic system and used as reference values. KT results were compared with the reference values to assess its accuracy. In addition, KT was tested on a force-measuring platform in a close to reality measurement.Based on Bland-Altman plots, the mean difference between KT and material testing machine was -0.63 N (0.4%), between KT and force-measuring platform was -0.11 N (0.7%), which proves the accuracy of its result.Laboratory experiments confirm that KT delivers precise and reproducible values, which provide base for clinical trials.