Citations
Citations
To correctly measure the knee joint angle, this study utilized a Qualisys motion capture system and also used it as the reference to assess the validity of the study's Inertial Measurement Unit (IMU) system that consisted of four IMU sensors and the Knee Angle Recorder software. The validity was evaluated by the root mean square (RMS) of different angles and the intraclass correlation coefficient (ICC) values between the Qualisys system and the IMU system.
Four functional knee movement tests for ten healthy participants were investigated, which were the knee flexion test, the hip and knee flexion test, the forward step test and the leg abduction test, and the walking test.
The outcomes of the knee flexion test, the hip and knee flexion test, the forward step test, and the walking test showed that the RMS of different angles were less than 6°. The ICC values were in the range of 0.84 to 0.99. However, the leg abduction test showed a poor correlation in the measurement of the knee abduction-adduction movement.
The IMU system used in this study is a new good method to measure the knee flexion-extension movement.
Citations
To determine the reliability and validity of hand-held dynamometer (HHD) depending on its fixation in measuring isometric knee extensor strength by comparing the results with an isokinetic dynamometer.
Twenty-seven healthy female volunteers participated in this study. The subjects were tested in seated and supine position using three measurement methods: isometric knee extension by isokinetic dynamometer, non-fixed HHD, and fixed HHD. During the measurement, the knee joints of subjects were fixed at a 35° angle from the extended position. The fixed HHD measurement was conducted with the HHD fixed to distal tibia with a Velcro strap; non-fixed HHD was performed with a hand-held method without Velcro fixation. All the measurements were repeated three times and among them, the maximum values of peak torque were used for the analysis.
The data from the fixed HHD method showed higher validity than the non-fixed method compared with the results of the isokinetic dynamometer. Pearson correlation coefficients (r) between fixed HHD and isokinetic dynamometer method were statistically significant (supine-right: r=0.806, p<0.05; seating-right: r=0.473, p<0.05; supine-left: r=0.524, p<0.05), whereas Pearson correlation coefficients between non-fixed dynamometer and isokinetic dynamometer methods were not statistically significant, except for the result of the supine position of the left leg (r=0.384, p<0.05). Both fixed and non-fixed HHD methods showed excellent inter-rater reliability. However, the fixed HHD method showed a higher reliability than the non-fixed HHD method by considering the intraclass correlation coefficient (fixed HHD, 0.952-0.984; non-fixed HHD, 0.940-0.963).
Fixation of HHD during measurement in the supine position increases the reliability and validity in measuring the quadriceps strength.
Citations
Objective: The purpose of this study is to identify how the isotonic and isometric mixed excercise training for 12 weeks take influence on the muscular strength, muscle size and foot pressure (by EMEDⰒ) in patients with degenerative knee joint disease.
Method: Seven patients with degenerative knee joint disease were chosen for the experimental objects and were trained isotonic exercise program for twelve weeks. Before and after exercise, CybexⰒ, Computed Tomography and EMEDⰒ were examined.
Results: After exercise program, peak torque, peak torque %Bwt and average power were significantly increased at 60o/sec and 180o/sec in both knee flexors and extensors. But peak torque ratio flexor/extensor were not significantly increased. Cross-sectional area of quadriceps and hamstrings were significantly increased. But there were no significant difference in the peak pressure at the heel and time (from initiation of initial contact to peak pressure at the heel).
Conclusion: We knew that isotonic and isometric mixed exercise training to the patients with degenerative knee joint disease for 12 weeks improved the muscular strength and muscle size, but this is not influenced on heel pressure. So, there may be needed to study with kinetic and kinematic analysis to more experimental patients.
Objective: The purpose of this study is to evaluate the effects of the cold air application on the subjective pain threshold of knee joint pain.
Method: We recorded the changes of the pain threshold in 60 patients before and after cold air application who complaint of knee joint pain. Patients were divided into 3 groups randomly with each 20 patients and each group received cold air application for 30 seconds, 1 minute, 3 minutes. Cold air of CRAis (Kyung-won Century, Korea) was applied to the anterior portion of the knee with a temperature of 30oC. The changes of the pain threshold was estimated by visual analogue scale.
Results: In 30 seconds treating group, VAS score was lowered 2.25±1.16 and 2.26±1.13 immediately after, and 30 minutes after cold air application, respectively (P<0.05). In 1 minutes treating group, VAS score was lowered 1.65±2.58 and 2.41±2.59 immediately after and 30 minutes after cold air application, respectively (P<0.05). In 3 minutes treating group, VAS score was lowered 1.94±1.80 and 2.10±2.3 immediately after and 30 minutes after cold air application, respectively (P<0.05). The VAS score was lowered significantly after cold air application in all groups, but there's no significant correlation between change of VAS score and cold air application time. In group with initial VAS score greater than 5, the VAS score was more decreased after cold air application.
Conclusion: Cold air application for 30 seconds using CRAis machine is useful treatment method for knee joint pain.
Objective: To develop and evaluate a new orthotic device for the knee to improve the ambulation patterns in paraplegic patients.
Method: The new orthotic device combined a high torque servo motor with a bail-lock knee joint, and a its wireless controller adopting open-loop control system. The device was tried in a paraplegic volunteer for two months, simultaneously with the conventional long leg brace.
Results: The new device could keep the orthotic knee joint exended during the stance phase, and allow the sequential flexion and extension of the joint during the swing phase. The new orthotic device provided both longer step length(p<0.05) and fewer cadence(p<0.05) maintaining the same walking speed. Also, a circumduction during the swing phase reduced, and the posture of the trunk became straighter. The stride time and the double support period became longer(p<0.05), and the magnitude of the shift of pelvic center increased(p<0.05).
Conclusion: The new orthotic device for the knee was developed and evaluated in a paraplegic volunteers who had failed to use the functional electrical stimulation. The results were satisfactory with a probable lower energy efficiency with the new orthosis. Further study for verification of the results seems to be necessary.