Relationship between muscle echo intensity on ultrasound and isokinetic strength of the three superficial quadriceps femoris muscles in healthy young adults.

[Purpose] The purpose of this study was to clarify the relationship between muscle echo intensity measured with ultrasound and the isokinetic strength of each of the three superficial quadriceps femoris muscles in healthy young adults. [Participants and Methods] We measured the echo intensity of the three superficial muscles of the quadriceps femoris in 25 healthy adults (10 males and 15 females; mean age, 22.3 years) using ultrasound. Moreover, we obtained the maximum force during isokinetic knee extension at 60°/s using an isokinetic dynamometer. [Results] In males and females, a significant negative correlation between echo intensity and muscle strength was found in the VM (r=-0.65 and r=-0.63, respectively). [Conclusion] In both males and females, only the muscle echo intensity of the vastus medialis was found to have a negative correlation with the maximum force during isokinetic knee extension at 60°/s. Our data lay the foundation for simplifying and rationally performing the measurement of muscle echo intensity of the quadriceps femoris. And it would therefore be sufficient to only measure the VM to clarify a relationship between EI and maximum isokinetic force in the quadriceps.

The immediate effect of the Honda Walking Assist Device on foot and ankle function in hemiplegic stroke patients.

[Purpose] We evaluated the reliability of the measurement function of the Honda Walking Assist Device and investigated the effect of the device on walking improvements, and foot and ankle function, in hemiplegic stroke patients. [Participants and Methods] We recruited 16 hemiplegic stroke patients who performed 10-meter walk tests, twice without assistance and once with device assistance. Based on the rate of change of velocity, we divided the participants into two groups and compared the walking parameters, the toe grip strength, the cross tests, and the maximum step width. Two examiners assessed the 10-meter walk test results, and the authors calculated the intraclass correlation coefficients for walking speed, stride length, cadence, flexion, extension, and scissor angles. [Results] The intraclass correlation coefficients were greater than 0.70 for all the walking parameters we measured. The device increased hip joint movement but did not alter the maximum walking speed of the stroke patients. The patients in the group with a greater change in velocity displayed lower toe grip strength and decreased maximum step width and used orthoses more commonly. [Conclusion] The walking measurement function of the device was reliable. The immediate effect of the device in stroke patients may be influenced by the level of paralysis and the presence of an orthosis.

Comparison of foot kinetics and kinematics during gait initiation between young and elderly participants.

[Purpose] To investigate the differences in foot kinetics during gait initiation between young and elderly participants using a modified multi-segment foot model. [Participants and Methods] Twelve young (23.3 ± 2.4 years) and 12 elderly participants (73.3 ± 3.9 years) were included in this study. Gait initiation was measured using a three-dimensional motion analysis system. We calculated the kinetic and kinematic values using our modified multi-segment foot model and compared those values with the values calculated using Bruening et al.'s multi-segment foot model. Modified gait initiation values were also compared between the elderly and young participants. [Results] Our modified multi-segment foot model, created using the Software for Interactive Musculoskeletal Modeling, showed similar values to those reported by Bruening et al. When we compared gait initiation between the elderly participants and their younger counterparts, the elderly exhibited lower torque and power values in the ankle, tarsometatarsal, and metatarsophalangeal joints. Additionally, the elderly exhibited a lower torque ratio in the distal joint than in the proximal joint (torque ratio: ankle joint >tarsometatarsal joint >metatarsophalangeal joint). [Conclusion] The elderly participants had less speed, stride, foot joint movement, moment, and power than the young participants. Moreover, the ratio of joint moment was smaller in the elderly participants. In elderly patients whose walking speed has decreased, consideration of the kinetics of the foot is important when deciding physiotherapy intervention.

Relative and absolute reliability of ultrasound measurements for the thickness of the soft tissue around the shoulder joint of young normal subjects.

[Purpose] The purpose of this study was to examine the reliability of ultrasound measurements by analyzing the relative reliability and absolute reliability when measuring soft tissue thickness around the shoulder joint. [Subjects and Methods] Eleven healthy young adults (22 shoulders) participated in this study. Thickness of the supraspinatus tendon, subacromial bursa, and biceps tendon was measured on both shoulders. This protocol was performed twice in the same day. The relative reliability of ultrasound measurement was evaluated using the intraclass correlation coefficient for determining the degree of consistency and agreement between two measures. The absolute reliability of the ultrasound measurement was evaluated using the standard error of measurement, minimum detectable change, and Bland-Altman analysis. [Results] Ultrasound measurements exhibited high relative reliability: intraclass correlation coefficients for the supraspinatus tendon, subacromial bursa, and biceps tendon thickness were demonstrated to be 0.91, 0.82, and 0.90, respectively. Bland-Altman analyses revealed no significant systematic bias between the repeated measurements for the supraspinatus tendon, subacromial bursa, and biceps tendon thickness. [Conclusion] These findings suggest that ultrasound measurement for the supraspinatus tendon, subacromial bursa, and biceps tendon thickness exhibited good relative reliability and no systematic errors were detected regarding their absolute reliability.