The purpose of this study is to examine the validity and reliability of the way using a chronaximeter as an inspection device for pain detection threshold value. Subjects were 20 healthy adult men and women. The fingertip of the left hand was stimulated at the various stimulus times, and pain detection threshold value was measured. It was confirmed that the difference in stimulus time resulted in the difference in the pain detection threshold. And, the subjects were ordered to choose the quality of the pain from the pain language list during the measurement. As for 300, 100, 10 and 1 msec, the tendency of the chosen language couldn't be specified. As for 1 and 0.1 msec, the subjects tended to choose the language of temporal or local expression. Measurement was carried out by three testers three times. Intraclass correlation coefficient (ICC) exceeded 0.77 at any stimulus time. Furthermore, the pain detection threshold was measured in 3 areas of the finger, the forearm, the brachium part. When a stimulus area was different, the threshold changed at the stimulus time of 300, 100 and 10 msec. The detection threshold of the finger area was smaller than those of the forearm area and the brachium area, and there was no difference between in the forearm and the brachium part. These results indicate that the present measurement method is simple and convenient for examining the pain detection threshold.

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The aim of the present study was to examine the responsiveness of skeletal muscle mechanoreceptors in atrophic muscle. Rat mechanoreceptor discharge in vivo were studied during ramp and hold stretching at the ankle joint by using a passive motion apparatus controlled by a personal computer. Discharge frequencies were measured at different angles of the ankle joint at 60, 90 and 120 deg/sec. Muscle mechanoreceptors from the soleus of immobilized hindlimbs, in plaster cast and suspension, were compared with age-matched normal animals at 12 weeks of age according to afferent impulses. The wet weights of the soleus muscles significantly decreased following two weeks of hindlimb immobilization. In contrast, the discharge frequency of the mechanoreceptors showed a linear function during the ramp stretch condition. Similarly, the activity of the mechanoreceptors in suspended hindlimbs showed a linear function, but this discharge frequency rate became incrementally higher than its contrast. In the immobilized hindlimbs by plaster cast, the discharge frequencies of the mechanoreceptor did not show a linear function but showed a exponential function. These results indicate that following muscular atrophy, achieved through two weeks of hindlimb immobilization, the function of the mechanoreceptors in skeletal muscle is changed.

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Reciprocal Ia inhibition in stroke patients was investigated before and after walking with and without Ankle Foot Orthotics (AFO). Five patients (mean: 47.6 years) with spastic hemiplegia due to cerebrovascular disease who can walk independently allowed soleus surface recording of H-reflex before and after treadmill walking at 1 km/h for 15 min. For test stimuli, the tibial nerve was stimulated at the popliteal fossa, and for conditioning stimuli, the common peroneal nerve was at the level of caput fiblae with the intensity of the lowest threshold for M wave. Time interval between test and conditioning stimuli were 0, 1, 2, and 3 msec. Statistical comparisons were made using with repetition in ANOVA and probability values less than 0.05 considered significant. Reciprocal Ia inhibition in spastic patients was reduced or abolished every conditioning test interval before and after walking. Although two cases showed reciprocal IA inhibition started 2 msec conditioning test interval at the rest, they had been facilitated H-reflex after walking. However, there was a tendency to decrease H-reflex amplitude after treadmill walking with AFO compared to before task.
We have found that reciprocal Ia Inhibition maintained in normal subjects after treadmill walking, but not in spastic hemiplegic patients. We have considered that it might be important for gait training or motor control of spastic patients to be maintained reciprocal Ia inhibition or distribute input volley with AFO. We would continue further investigation, and would like to examine the relationship between the effects of reciprocal Ia inhibition by AFO and function changes of the neurological organization, such as reciprocal inhibition conjunctions.

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There are some reports on the effect of prevention by exercise for atrophic muscle fiber in model mice of dystrophy. However, it is still unclear how much exercise would be beneficial for the atrophic muscle fibers in muscular dystrophy. We therefore studied the effect of isometric exercise on atrophic muscles in mdx mice after hindlimb suspension (HS). Twenty male mdx mice were used and divided randomly into four groups: control, HS only (mHS), non-exercise for 2 weeks after HS (mHS-NE), and isometric exercise with a load weight after HS (mHS-E). HS was carried out for 2 weeks. The isometric exercise was done with stationary support on a grid at 80゜, equal to 50% of body weight attached to the tail for 10 min/day, 5 days/week for 2 weeks. We obtained extensor digitorum longus (EDL) and soleus (SOL) muscles followed by a section stained with hematoxylin-eosin. Quantitative assessment of the muscles include the diameter of muscle fibers, the rate of necrotic fibers, the internal nuclei fibers and splitting fibers. The fiber diameter of both muscles in the mHS-NE and mHS-E groups showed significant hypertrophy compared with the mHS group. And the fiber diameter of the SOL in the mHS-E group had significant hypertrophy compared to other groups. While there was no significant difference in the mean muscle fiber diameter of the EDL between the mHS-NE group and mHS-E group, the isometric exercise didn't induce necrotic fibers, internal nuclei fibers and the splitting of the EDL. In the SOL, however, the rate of internal nuclei fibers in the mHS-E group increased compared with the mHS-NE group. We found that exercise for the atrophic muscle fibers in muscular dystrophy could bring about muscle fiber hypertrophy, but it is possible that exercise could promote the necrosis of any muscle fibers.

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The standard for evaluating basic movements is hard to be systematized. In the present study, paying attention to a rising motion among those basic movements, we examined the effect of location of the shoulder joint on the rising motion. Subjects were 10 healthy males (average age: 21.3 ± 1.77 years, average height: 171.3 ± 3.97 cm, average weight: 66.5 ± 10.4 kg). For comparison with patients who had experienced cerebral vascular accident, two female subjects also participated in the study. The surface electrodes were placed on teres major muscle, infraspinous muscle, rhomboid muscle, and straight muscle of abdomen, and the activities of periarticular muscle of shoulder joint and trunk flexors were measured. The measurements were made in rising motions both with the shoulder joint abducted at a specified degree and with the normal position of shoulder joint, and the results were compared. The abduction angles of shoulder joint were 10, 30, 60, 90 and 120 degrees, and data were statistically analyzed using the Spearman's order correlation test followed by the χ²-test. In healthy male subjects, as for relationship between specified degree and activities of periarticular muscle, muscular activities of rhomboid muscle and infraspinous muscle were found biased(p<0.05), and in female subjects muscular activities tended to be lower in normal position of shoulder joint than in order positions. In the patients, each muscle tended to show a specific pattern of activity, which suggests that muscle activities are affected by the abduction degree of shoulder joint in the starting posture.

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We have often experienced that some stroke patients could walk faster or flex the knees more during swing phases after therapeutic electrical stimulation (TES) to tibialis anterior muscle of a hemiparetic side. The purpose of this study is to investigate the time-course of the effect of TES to tibialis anterior muscle of a hemiparetic side.
The subjects were ten hemiplegic patients who could walk independently with or without a cane and an ankle foot orthosis. We measured the knee flexion angle of the hemiparetic side during swing phases before TES (control), 0 min after TES, and every 30 min until 120 min after TES. The results showed that the flexion angle increased significantly at 0 min, compared with that of eight control subjects, and that the angle tended to increase 120 min after TES.
We concluded that the effect of TES to tibialis anterior muscle was maximal just after TES, and might continue several hours, although the time-course of the effect was different individually. We supposed that some factors of impairment such as muscle tonus might influence the course.

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We evaluated the effectiveness of the complex physical therapy (CPT) for lymphedema in the limbs of twenty-five patients who had been admitted to our hospital. Twenty-two patients were of secondary lymphedema, and eighteen were status post treatment of uterine cancer. CPT advocated by Foeldi et al. consisted of skin care, manual lymph drainage (MLD), compression therapy with elastic bandages or elastic stockings, and exercise therapy under compression.
MLD functionally operates to enhance the lymph drainage proximally in both contralateral and ipsilateral truncal quadrants of the torso, then in the proximal limb, and then from the distal to proximal portion of the edematous extremity. Swelling ratio of all patients on admission was 26.5 ± 14.1%. At discharge it was 14.9 ± 9.9%. Edema reduction ratio (ERR) of the all patients was 46.1 ± 19.2%, and the effectiveness was recognized in 80.0% of cases with ERR of more than 30.0% at discharge.
Lymphedema should be accurately diagnosed in the early stage and be treated with CPT correctly by clinicians who understand lymphedema thoroughly and are well trained.

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To investigate the effect of unilateral cast immobilization, one hindlimb of rats was immobilized for 2 weeks by a cast and remobilization was carried out for up to 4 weeks. Rats were sacrificed at the start of immobilization, after 2 weeks of immobilization and after 1, 2, 3 and 4 weeks of resumed normal activity following cast removal. After euthanasia with ether, the gastrocnemius, soleus, and tibialis anterior muscles as well as the bones of their proximal attachments were removed. Cryosections were used for hematoxylin-eosin staining and ATPase activity. Two weeks of immobilization resulted in a significant decrease of wet weight of muscles and reduction of muscle fiber cross-sectional area. Relative incidence of Type II fibers increased in the soleus and gastrocnemius muscle after two weeks of immobilization and bone weights decreased. After remobilization, muscle atrophy due to immobilization gradually reversed. However, some atrophy still remained 4 weeks after cast removal. The immobilization caused severe atrophy in the leg, with complete recovery requiring much more time than the period of immobilization. This suggests a need to investigate interventions to facilitate the recovery of atrophied tissues.

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