The meaning of some key words, such as the center of gravity, the floor reaction force, the joint moment and the joint power is explained to understand biomechanics of human movement. The movement of the center of gravity is caused by the floor reaction forces, and the muscle forces are the motive power of the floor reaction forces. The joint moment is a parameter for the muscle activity during movement, and the joint power, which is calculated by the joint moment and the joint angular velocity, shows the activation pattern of muscles. The activity of muscles around each joint is explained by the gait data during level walking.

View full abstract

The mechanical characteristics of Ankle Foot Orthosis (AFO) depends on the magnitude of resistive moment and its activation period during gait. Desiable characteristics of AFO for hemiplegic patients were investigated based on the gait data. The results indicared that desirable AFO induced a large amount of resistive moment to the dorsiflexion of the ankle joint at the initial contact, and implemented smooth dorsiflexion of the ankle during the mid stance. An AFO with oil damper was developed to realize these characteristics. Adequate control of the knee joint movement during the stance phase and shock absorption at the initial stance can be realized when patients walk with the oil damper AFO. Moreover, the magnitude of the resistive moment can be adjusted to the condition of each patient, and the oil damper AFO is therefore adequate to patients in the convalescent stage, whose physical condition is unstable. The characteristics of AFO and the effects of AFO characteristics on hemiplegic gait are explained here.

View full abstract

The purpose of this paper is to introduce biomechanical aspect to the prosthetic gait. The knee joint moment during gait with transfemoral prostheses is mainly explained. The control system of the knee joint of the transfemoral prosthesis is divided into two types; the stance phase control and the swing phase control. In the stance phase control system muscle force around the hip joint and the prosthetic knee joint structure make the smooth progression of the center of gravity, keeping the knee joint stabilization. The control of the knee joint movement during the swing phase is required for the swing phase control system. In recent years various kinds of prosthetic knee joints have been commercially available, and the features of these joints and the prosthetic gait wearing them are explained.

View full abstract

Paying our attention to joint moment during gait of hemiplegic patients after stroke, we examined mechanical characteristics of hemiplegic gait, causes for decrease in joint moment and clinical applicability of our results.

View full abstract

Knee joints control the distance between the body and floor, and regulate upper- and lower-knee movements. Loss of knee joint mobility results in disadvantages of daily life, especially locomotion, and exerts a greater effect on vertical weight shift, compared with other joints. Patients with disorders show characteristic systemic movement, and the disorder is often considered to result from movement caused by sports diseases. It is therefore necessary to examine causes of each disease, and careful attentions should be given to the extent from etiology to prevention. From a viewpoint of motion analysis in physical therapy, visual analysis like joint moment would be required.

View full abstract

The progress in the parts for upper and lower extremity prostheses has been remarkable. As a lower extremity prosthesis, C-Leg, a knee joint provided with a sensor, microprocessor and oil pressure controller serves to improve QOL of amputees. A myoelectric upper extremity prosthesis is one of the long-established protheses, and its popularization as public provision in Japan depends on to what extent it will be applied in the clinical setting. The present article reports the development process and construction of C-Leg and a myoelectric upper extremity prosthesis, as well as their contribution to amputees' QOL.

View full abstract

A research method of clinical motion studies was discussed. Human motor activities in daily life are evolved on the basis of movement coordination, and the coordination is dissolved in motor disability. Reaching and its disturbances in spastic hemiparesis were exemplified. Clinical motion studies in rehabilitation should be explored under wide interests of motor control research.

View full abstract

The measurement of joint range of motion by the conventional goniometer requires the time and skilled technique of examiners, such as a palpation of bone index and preparation of basic or locomotive axis. In the present study, joint range of motion was simply measured by an inclination goniometer in order to examine the validity and reproducibility of measurement values. Among 17 healthy male subjects (average age: 22.3 years), flexion angles of elbow and knee of 34 extremities were measured both by the conventional goniometer and the inclination goniometer. There was a high correlation between the measurement values by the inclination goniometer and that by the conventional goniometer (r=0.77-0.89), and only two extremities of elbow joint indicated a measurement error of over 10 degrees. In order to examine the reproducibility of measurement values, intraclass correlation coefficient (ICC) was obtained. Intrarater and interrater ICC were higher in the measurement by the inclination goniometer than in that by the conventional goniometer. These results certify the validity and reproducibility of measurement of joint range of motion by the inclination goniometer. This simple method is applicable to the improvement in self-management of patients and to learning process of measurement techniques among physical or occupational therapy students.

View full abstract

The student who has proper meta-cognition is able to recognize problems appropriately, and he (she) is expected to have a high scholastic ability. We examined the relationship between meta-cognition and the scholastic ability in order to find a better teaching method for physiotherapy. The result revealed that a significant correlation between meta-cognition and the scholastic ability (r=0.95, p<0.01). This proves not only a close relationship between them, but also an importance of obtaining meta-cognition during the learning process. So, if students have lower ability to use meta-cognition, they will have more difficulty in gaining achievements. The results suggest that, as physiotherapy education, giving knowledge to students one-sidedly is not a good teaching method, and that the method for developing meta-cognition is required.

View full abstract

We hypothesized that the stability and a larger stability area of the center of gravity in a single elbow support position are the factors that determine the ability of sitting up by way of a single elbow support position in patients with hemiparesis. The purpose of this study was to confirm this hypothesis. The locus of the center of pressure (COP) in a single elbow support position under the two conditions and sitting up time were measured in 17 patients with hemiparesis after stroke, and relations among these parameters were examined. Two conditions for measurements of COP were that subjects maintained a static position (static condition), and they moved their upper body to two directions (anterior and posterior)(dynamic condition). The sitting up time was the performance time from supine to long sitting by way of a single elbow support position. As a result, no correlation was observed between the static and dynamic conditions. The sitting up time was found to correlate significantly with the length of trajectory (LNG) of COP under the dynamic condition. It was indicated that patients with hemiparesis could sit up smoothly if dynamic stable area in a single elbow support position was larger, and that training to extend the dynamic stable area should be included in physical therapy.

View full abstract

The present study was designed to examine the interrater and intrarater reliability of measurement of knee joint angle by using a goniometer on digital video pictures. A goniometer was recorded under various positions and angles by a digital video and the data was introduced into a personal computer. Six examiners were instructed to read the angles in the goniometer using a graphic software for PC, and interrater and intrarater reliability of obtained results was studied. According to generalizability theory, generalizability coefficient (G) was obtained in order to elucidate the numbers of examiners and repetitive measurements, which guarantee high reliability. As a result, the interrater reliability was small, and the intrarater reliability was relatively high among experienced examiners. It was questionable that the lowest limit of 95% reliability range satisfied sufficient reliability. The minimum condition where G was 0.9 and over was that one examiner measured the angle one time. The minimum condition where G was 0.95 and over was that one examiner measured the angle more than three times, or more than two examiners measured it one time. The results indicate that the measurement of knee joint angle by using digital video pictures offers no problem in the interrater and intrarater reliability under these measurement conditions.

View full abstract