[Purpose] The purpose of this study was to examine the relationship between the positions of the shoulder joint that enable easy getting-up from a side-lying position, and the muscle activity that occurs at the same time. [Subjects] Thirty (25.8 ± 4.3 years) and ten (26.6 ± 4.9 years) healthy adult men participated in this study. [Methods] Research on positions of the shoulder joint that enabled easy getting-up was conducted, while getting up from right side-lying with support from the right elbow, with the shoulder bent at the five different angles of 10 degrees, 30 degrees, 60 degrees, 90 degrees, and 120 degrees. Then the most favorable posture for getting-up was selected and statistically verified by χ2. Next, to investigate the correlation with muscular dynamics, surface electrodes were applied to the posterior fibers of the deltoid, the triceps muscle, the infraspinatus muscle and the rectus abdominal muscle, and rising-up from a right side-lying position to the right hand palm support position was performed. The independent χ2 test and the Spearman rank-difference correlation were performed for the statistical evaluation. [Results] For ease of getting up, no statistically significant differences were found, but there was a strong tendency towards easiness in the 60 and 90 degree shoulder angle positions. For muscle action, significant differences were found in the posterior fibers of the deltoid and the rectus abdominis muscle, depending on the angle set. The muscle activity decreased as the angle increased. [Conclusion] In getting up from a side-lying position, the relation between angles at which it was subjectively easy to get up and muscle activity of the muscles surrounding the shoulder joint and abdominal muscles was unclear, but the possibility that weight transfer exerted an influence was suggested.
[Purpose] The purpose of this study was to clarify the expression changes of MyoD mRNA under reloading rat skeletal muscles after hindlimb suspension. [Subjects] The subjects were 27 Wistar male rats aged 8 weeks old. [Methods] They were randomly divided into a control group (n=5) and 4 experimental groups (n=5 to 6). The experimental groups were all submitted to 14 days of hindlimb suspension provoking muscle disuse atrophy, and afterwards they were assigned to no-reload hindlimb suspended group (HS) and 2, 7 and 14 days reloading groups (2D, 7D, 14D). [Results] The MyoD mRNA expression level increased in the HS group was significantly higher in the 2D reloading group and decreased to controls levels in the 7D reloading group. [Conclusion] The MyoD mRNA expression results suggest that reloading after hindlimb suspension stimulates satellite cell activation. Furthermore, the peak of MyoD mRNA expression was observed after 2 days of reloading.
[Purpose] The purpose of this study was to determine if a 30-minute twice daily prolonged stretch could prevent range of motion limitation in rats. [Subjects and Methods] Twenty-three 8-week-old female Wistar rats were divided into three groups. The right ankle joints of all the rats were fixed in full plantar flexion for a week with plaster casts. The first group was immobilized continuously throughout the experiment (G1). In the second and third groups, the casts were removed daily, and the foot was held in dorsiflexion for 30-minutes once a day (G2) and 30-minutes twice a day (G3), respectively. [Results] The range of motion of G1 and G2 significantly decreased from the first day of the experiment to the last day. However, the range of motion of G3 did not show any significant difference between the first day and the last day. [Conclusion] These results suggest that prolonged stretching for 30-minutes twice daily may be effective for the prevention of joint contractures in rats.
[Purpose] The purpose of this study was to evaluate tissue oxygen utilization and blood flow in patients with chronic respiratory failure (CRF). [Subjects] The subjects were divided into three groups: twelve subjects with chronic respiratory failure, twelve healthy older subjects, and thirteen healthy young subjects. [Method] A near infrared spectrometer was used to monitor tissue oxygenation, and the probe was placed over the flexor muscle. The subjects performed 3min rhythmic handgrip (HG) exercise at 10 and 30% of maximum voluntary contraction force in a random order. Forearm blood flow was estimated by the rate of increase in the sum of oxy-hemoglobin (OxyHb) and deoxy-hemoglobin (DeoxyHb) during venous occlusion, and muscle oxygen utilization by the rate of decrease in the difference between OxyHb and DeoxyHb during arterial occlusion. [Results] Forearm blood flow in the CRF group was significantly lower compared to the older group during 10% HG and the younger group in 30% HG. Muscle oxygen utilization in the CRF group was significantly higher than the older and young groups in 10% HG. [Conclusion]We conclude that the CRF patients desaturate their muscles more than normal control subjects at a lower work level due to insufficiency of blood flow to the exercising muscles.
[Purpose] The aim of this study was to evaluate the test-retest reliability of isometric muscle strength measurements made using a hand-held dynamometer restrained by a belt. [Subjects] The subjects were 37 healthy adults (18 men and 19 women) with a mean age of 21.9 years. [Methods] Measurements were made on the dominant leg using a hand-held dynamometer (μTas MF-01 or F-1, Anima Corp., Tokyo) and a belt to fix the position of the body part under test. The strengths of the following 10 muscle groups were evaluated: flexors, extensors, abductors, adductors, internal rotators and external rotators of the hip; flexors and extensors of the knee; and dorsiflexors and plantar flexors of the ankle. Each measurement was repeated after at least 30 seconds of rest in three sessions: in the morning, in the afternoon on the same day, and one week later. [Results] The intraclass correlation coefficient (ICC) for the first and second sets of measurements made in each session ranged from 0.75 to 0.97. ICC for the highest measurements of each muscle group in each of the three sessions ranged from 0.56 to 0.91. [Conclusions] The test-retest reliability of isometric muscle strength measurements of the lower limb made using a hand-held dynamometer equipped with a stabilizing belt varies widely, depending on the muscle action tested, and it would be better to repeat the measurements on different occasions.
[Purpose] This study was aimed to explore factors related to functional decline of community dwelling elderly from the aspect of activities of daily living in a nine-year follow-up study. [Subjects] The subjects were 141 males and 151 females living in a farming village neighboring a large city in the Chubu District of Japan. [Methods] We investigated the age, sex, and presence/absence of illness, social interaction, and exercise habits of each subject. The baseline study was conducted in 1996 with a follow-up in 2005. The chi-square test and multiple logistic regression analysis was used to examine the relationships of independence in physical function with age, sex, and presence/absence of illness, social interaction, and habitual exercise. Analyses were performed using the computer program SAS. [Results] The results of the present study indicate that decline of physical function was related with decline of ability to step up and down. [Conclusion] It seems advisable to provide an intensive program for individuals when they begin to have difficulty stepping up and down (the group at risk). However, the validity of the program identified by the authors has not yet been tested. At the same time, it would be desirable to implement a program prepared on the basis of these findings and evaluate its effectiveness.
[Purpose] Kendo practitioners often suffer from left low back pain. The present study was undertaken to analyze the features of range of motion (ROM) of the hip joint of kendo practitioners and their relation to prevention of lower back pain. [Subjects and Methods] The study involved 37 male university kendo practitioners: 26 kendo practitioners having a history of lower back pain, 11 kendo practitioners having no history of lower back pain. In accordance with the method of ROM measurement set forth by the Japanese Orthopaedic Association, the same examiner measured hip joint ROM during passive flexion/extension and internal/external rotation. [Results] In the low back pain group, no laterality was noted in the ROM of the external rotation. However, ROM of the internal rotation was significantly smaller on the left side than on the right side. The range of rotation was significantly smaller on the left side than on the right side. [Conclusion] The ROM of hip rotation on the left side was significantly diminished (less than 90 degrees) only in the low back pain group, and the laterality in ROM of left hip rotation was significantly greater in the low back pain group than in the non-low back pain group (p<0.05). These findings suggest that small ROM of left hip rotation is a factor responsible for the onset of lower back pain.
[Purpose] To compare the reliability of goniometric measurements of knee flexion obtained in three different body positions of patients with total knee arthroplasty (TKA). [Subjects] The knees (151) of 92 TKA patients were the subjects of this study. [Methods] The range of flexion was measured at three instances: preoperatively, postoperative fifth day and at the time of discharge by universal goniometer measurement with the patient positioned in the supine, prone and sitting positions. [Results] There were no significant differences between the range of motion measurements in the three testing positions at the three instances. Also, the results from the three different testing positions were highly correlated (r>0.80). [Conclusion] The results of this study indicate that the position of the patient during the evaluation of range of knee flexion does not affect the results and that the three different body positions can be used interchangeably.
[Purpose] To determine the ankle evertor/invertor maximal torque ratios (E/I) in the normal population which could be used as reference values during clinical evaluations and rehabilitation efforts and also to investigate the effect of age, gender and limb dominance on E/I. [Methods] Concentric ankle E/I was tested at 30 and 120 degrees/second using an isokinetic dynamometer for 79 healthy volunteers and the effects of age, gender, limb dominance on E/I were analysed. [Results] E/I values increased slightly with increasing age and there were statistically significant differences between age groups of 20-29 and 60-upper ages, and 30-39 and 60-upper ages with respect to left E/I (120 degrees/second) values. There were no significant differences between male and female subjects and between dominant and non-dominant limbs. [Conclusion] Ankle evertor/invertor peak torque ratios are affected by age but not by the dominance of the limb and the patient's gender. The ratios observed in different age groups in our study can be used as reference values in clinical evaluations and rehabilitation programs without taking into account the dominance of the limb and the patient's gender.
[Purpose] In rehabilitation, it is important to prevent regressive change caused by denervated muscle atrophy. We determined the effect of neuromuscular electrical stimulation on expression of insulin-like growth factor-1 and 2, and their receptors' mRNA in skeletal denervated muscles and sciatic nerves of Wistar rats. [Methods] Denervation was performed by crushing the bilateral sciatic nerves. The day following the denervation, the bilateral gastrocnemius muscles were electrically stimulated percutaneously, for 30 min/day at 4 mA intensity and 10 Hz frequency. After 3 weeks, the muscles and crushed site of the sciatic nerve were dissected. [Results] Relative muscle weights were decreased by denervation; however, the decrease was less after electrical stimulation. Expression of insulin-like growth factor-1 and 2 mRNA in denervated muscle and sciatic nerve were increased by electrical stimulation. [Conclusion] In general, skeletal muscle growth and atrophy is regulated by insulin-like growth factor-1. The neurotrophic factors, including insulin-like growth factor-2, are produced in denervated muscle and initiate regeneration, and are transported retrogradely by axoplasmic transport. Therefore, our results demonstrate that electrical stimulation retards muscle atrophy and promotes nerve regeneration following denervation by increasing insulin-like growth factors' mRNA in the denervated muscle.
[Purpose] This study was conducted to establish an understanding of how health, medical treatment and welfare service providers conceptualize the term "community-based rehabilitation (CBR)", based on comparison with community care and to provide cautions in use of CBR in support activities. [Subjects and Methods] The subjects were 2894 randomly selected workers supporting the elderly and disabled in 982 institutions in all areas of Aomori Prefecture using the stratified cluster sampling. The questionnaires were sent by mail. The subjects selected items that they considered to be the content of CBR or community care from 22 social resources available for the elderly and disabled (multiple answers allowed). [Results] The subjects recognized as CBR were limited to outpatient treatment and rehabilitation, day service and day care with rehabilitation service, home-visit rehabilitation service and functional training. The subjects considered that the concept of community care was wider than CBR regardless of occupation, however, the concept of approximately half of social resources varied between occupation. [Conclusion] In CBR as used in support activities, it is necessary to educate healthcare and welfare service providers about the definitions according to the substance of the definition of these terms in advance. Furthermore, the concept of CBR should be standardized between them.
[Purpose] Parkinson's disease (PD) leads to stance instability in the late stage of the disease. Conventional studies of the center of pressure (COP) have difficulties characterizing postural instability in the early stage of PD. The present study analyzed stabilograms of PD patients using a recently developed method, detrended fluctuation analysis (DFA). [Subjects] The subjects were 7 PD patients in stages I-III of Hoehn and Yahr, and 10 age-matched healthy elderly (HE) persons. [Method] COP signals were measured during quiet standing, and subjected to DFA and conventional analysis. DFA parameters (scaling exponents) relating COP fluctuation to time interval showed similar behaviors both in PD and HE subjects. Both in the anterior-posterior (AP) and medio-lateral (ML) directions, three exponents, α1, α2 and α were obtained for short- and long-term fluctuations, and the whole range, respectively. [Results] Magnitudes α, α1 and α2 were almost the same: α1 ≈1.5, α2 ≈1.0, and α ≈1.3. The crossover points dividing the short- and long-term fluctuations in the AP direction, however, differed between PD and HE subjects. The former was about 0.6 times shorter than the latter. [Conclusion] PD patients may control upright posture with the similar postural strategies to HE subjects, but the switching times between the short- and long-term strategies may be different.