To clarify the importance of evaluation of isokinetic endurance, we evaluated the relationship between the results of evaluation of the isometric peak torque, isometric endurance, and isotonic endurance each parameter (total work, decrease rate, 50% attenuation number) of evaluation of isokinetic endurance (50 knee bends between 90° and 40° of knee flexion at an angular speed of 180°/sec with maximum efforts) and the effects of sex on each parameter in the knee extensor of 17 normal subjects. As isometric endurance, knee extension at about 70° of knee flexion was continued under the maximum efforts, and the time (seconds) until the isometric peak torque decreased to 50% was measured. As isotonic endurance, knee extension exercise from 90° to 40° of knee flexion (isometric peak torque, 25%) was performed with a rhythm of once every 2 seconds, and the time at which the rhythm was disturbed or the fixed angle was not reached was defined as the end of exercise. The number of exercises until the end of exercise was evaluated.
1) The total work was higher in males and it was well correlated with muscle strength but not with the decrease rate or attenuation number.
2) The decrease rate was lower in males. It was correlated with isotonic endurance, being highly correlated in females, and was well correlated with isometric endurance only in males.
3) No sex difference was observed in the attenuation number, which was correlated with isotonic endurance and decrease rate.
Marked sex differences were observed in each parameter of isokinetic endurance. In addition, these parameters contained various elements of muscle endurance and seemed to differ from isometric or isotonic endurance. The evaluation characteristics of the decreased rate were similar to those of the attenuation number. On the other hand, the total work differed from these parameters.
For serial evaluation of isokinetic endurance, the total work seemed to be appropriate. However, further longitudinal studies on each parameter are needed.

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The present study was performed in order to elucidate the histochemical properties of intact rat quadriceps muscles and the differential effect of tenotomy of the patellar tendon on one-joint muscles: vastus medialis muscle (VM), vastus intermedius muscle (VI) and a two-joint muscle: rectus femoris muscle (RF).
Thirty-four white adult female Wistar strain rats weighing 250-300 g were used in this study. The patellar tendon of the right limb was tenotomized and the contralateral limb was served as a control. At the same time, histochemical observations were made on ten normal rat quadriceps muscles. VM, VI and RF muscles from six animals each were excised at intervals of 3, 6, 9 and 12 weeks after tenotomy. Fresh frozen serial cross sections were stained with hematoxylin and eosin (HE) and ATPase activities were observed.
The results obtained were as follows:
(1) The mean diameter of the type I fibers in the deep portion of the quadriceps muscles was larger than that in the superficial portion in the control rats (p < 0.05).
(2) In the control study, a higher proportion of type II fibers was observed in the superficial portion of RF and VM muscles. On the other hand, a higher proportion of type I fibers was observed in the deep portion of the same muscles.
(3) Three weeks after tenotomy, both type I and II fibers of one-joint muscles, VM and VI, were seen to be smaller in diameter than normal (p < 0.01), but histological changes were only slightly noticeable. These changes included the appearance of central nuclei, opaque fiber (early necrotic fibers) and hypertrophic (atrophic) fibers. Six weeks after tenotomy, an increase in the diameter of muscle fibers was seen. In 9 th and 12 th weeks after tenotomy there were some hypertrophic fibers found.
(4) Three weeks after tenotomy, there was only a slight decrease seen in type II fiber diameter of RF. However, in the 6 th week there was a moderate decrease seen in the type I fiber diameter in the deep portion of RF.
Based on these results, it seems likely that the histochemical properties of the intact rat skeletal muscle and the differential effect of tenotomy on one-joint and two-joint muscles are dependent upon anatomical position and functional utilization.

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We examined clinical course of impairments and disabilities in 37 patients with spinocerebellar degeneration to determine their relationships.
The period between the onset and bedridden state ranged from 5 to 20 years, and the complications in patients with olivopontocerebellar atrophy (OPCA) tended to progress more rapidly than in those with Menzel type. The incidence of complications with parkisonism and autonomic symptoms was higher in OPCA patients than in patients with Menzel type.
The progress of gait disturbance was related to the severity of ataxia, parkinsonism and muscle weakness. Since muscle weakness was considered to be a secondary impairment caused by the disuse syndrome, the importance of therapeutic exercise for the maintenance of muscle strength was confirmed.

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Since 1986, we have been making the light crutch using aluminum pipe (underarm crutch) for those patients with rheumatoid arthritis (RA) who have difficulty in using commercially available crutches. Recently, we have made several evaluations, including engineering one, for the verification of the safety of the present crutch. As a result, no problem on the crutch material itself was found, but structural problem on fitting the crutch with a grip was thought. More than 100 crutches have so far been prescribed and are actually in good use without hitherto-reported ruptures and the like. The present crutch, which satisfies such conditions, “light (450g), body weight-supportable and easy to draw out” as are requested for crutches for RA patients, is thought to be the most suitable for RA patients.

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The purpose of this study was to investigate whether the cardiovascular responses to isometric trunk rotatory exercise are influenced by changes in the duration of exercises. In addition, differences in the cardiovascular responses to isometric exercise using different muscle groups (trunk rotation, elbow flexion, and knee extention) were studied. Six healthy men volunteered to participate in this study. Isometric trunk rotatory exercise was performed using Cybex Trunk Rotation Unit at three different exercise times (5, 10, and 20 sec). Two other isometric exercises (elbow flexion and knee extension) were performed with 5-sec contraction. Heart rate (HR), systolic blood pressure (SBP), mean blood pressure (MBP), and diastolic pressure (DBT) were continuously measured non-invasively with a servo-plethysmomanometer (Finapres type 2300) every beat. Peak HR, SBP, MBP, and DBP values were compared between the different exercise conditions. During trunk rotatory exercise, peak HIR significantly increased with the increase in exercise time, i.e., HR (20 sec) > HR (10 sec) > HR (5 sec). Peak SBP significantly increased with an increase in exercise time, i.e., SBP (20 sec) or SBP (10 sec) > 5 sec. Peak MBP significantly increased with an increase in exercise time, i.e., MBP (20 sec) > MBP (5 sec). However, Peak DBP was not significantly different at the three different exercise times. During 5-sec isometric muscle contraction, peak HR, SBP, MBP, and DBP progressively increased from knee extension to elbow flexion to trunk rotation, but there were no significant differences between the three muscle groups. These findings indicate the importance of exercise time during isometric trunk rotatory exercise.

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This study was designed to clarify influences of a short leg brace on knee joint motion of hemiplegic patients with various ankle plantar-flexion limitations.
We had the results of measuring nine normal subjects instead of hemiplegic patients.
Depending upon the increment in plantar-flexion limitation, the results were as follows;
1) The maximal value of the Y-axis acceleration was increased.
2) The maximal value of the Z-axis acceleration was decreased.
3) The knee joint angle and quadriceps femoris I-EMG values were significantly increased.
4) Triceps surae I-EMG showed no change.
These changes were found to occur simultaneously.
Therefore, we suggest that the application of a short leg brace for hemiplegic patients with various ankle planter-flexion limitations should be considered to accelerate the knee joint level and knee joint angle as well as related muscular activities.

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[in Japanese]

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It is important to know the actual status of the life of the patients who suffered from osteoarthritis and underwent total hip replacement (THR). We visited their homes to evaluate their activities of daily living (ADL) using the video system.
The patients were classified into three groups: short-term group (from 1 to 3 years after THR was performed), middle-term group (from 5 to 8 years after THR), and long-term group (over 10 years after THR).
Post-operative ADL was maintained well in most of the patients and many of them were also satisfied with their results of operation. However, some of them in long-term group had a problem such as aggravated walking ability due to aging. Some had trouble in walking, putting on and off the socks as well as squatting activities in all the groups.
It is concluded that the assessment of actual status of their ADL as well as other orthopedic evaluation is indispensable for the rehabilitation of the patients who had THR.

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The purpose of this study was to evaluate activities of daily living (ADL) of the patients with osteoarthritis (OA) of the knee and to clarify the factors affecting them. Fifteen patients with OA of the knee were served as the subjects (those who had bilateral involvement were 8, and those who had unilateral involvement were 7). All patients were divided into 2 groups according to the independent level of ADL and gait ability: one group consisting of the patients who had not so much trouble in ADL (group A) and the other consisting of the patients who had trouble in ADL (group B).
They were further classified into 2 groups depending on gait ability: group C maintained gait ability well, and group D did not. Pain, deformity and muscle strength of the knee as well as degree of obesity were assessed and compared between these two groups.
As a result, patients in groups B and D are likely to have weakness of knee muscle strength in association with severe knee pain. These results indicate that determinants of independence of ADL of these patients greatly depend upon the muscle strength and pain of the knee joints.

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