The purpose of this study was to investigate whether body positioning would bring about any change in inspiratory and expiratory muscle strength expressed in terms of maximal negative inspiratory pressure (P Imax) and maximal positive expiratory pressure (PEmax). The PImax and PEmax measurements were carried out on 20 participants in sitting, half lying, `slumped' half lying, supine lying, right side lying, and left side lying. The one-way analysis of variance showed that PImax and PEmax values were within normal range for all positions. It was hypothesized that a significant change in PImax and PEmax would occur with alteration of the body position in healthy persons, but this was proven negative. The findings were similar to those found for people with chest pathologies; that is, the highest PImax and PEmax values were evident in the more erect positions than recumbent positions. Possible reasons and implications for such findings are discussed in terms of the force of gravity acting on the thoracic cage in various body positions and the length-tension relationship of both the inspiratory and expiratory muscles.
Professionals working in human-related services have been found to suffer burnout to an increasing degree, which, in turn, affects their work performance, and the reason for it is often due to excessive work-related pressure. Using the Japanese version of the Maslach Burnout Inventory (JMBI), this study investigated various factors associated with burnout among physiotherapists from the prefecture of Ishikawa in Japan, and the results were analysed to understand the relationship among these factors. Out of 243 practising physiotherapists surveyed throughout the prefecture, 163 met the established criteria for inclusion in the study. The scores for personal accomplishment were significantly lower than those of physiotherapists in the United States, but significantly higher than nurses in Japan (p<0.001). The factor analyses revealed that statements belonging to each factor described the specific concepts. A positive correlation was demonstrated between Factor 4 and age of the therapist and Factor 4 and therapist's number of years of practice (p<0.05), Factors 2 and 4 and the number of years at present employment (p<0.01), and Factor 4 and the therapist's time spent for clients (p<0.01). As for the gender difference for the JMBI, male respondents' scores were high for Factors 2 and 4 (p<0.01). Possible reasons for and implications of these findings are discussed in terms of recognition of the factors which contribute to burnout.
The purpose of this study was to attempt to classify physically disabled schizophrenic patients from the aspect of the physical therapy outcome, and to utilize this classification for the establishment of guidelines and therapeutic strategies in these patients. A cluster analysis was performed to evaluating patient's psychosis according to an original psychosis assessment scale. The final motor function was assumed as the physical therapy outcome, and putative influencing factors were obtained. Herein we show that three factors, namely age, initial motor function, and decreasing activity, are important to estimate the physical therapy outcomes in these patients. Considering these factors, together with an assessment of the psychosis of the patients, we have classified physically disabled schizophrenic patients into three types to achieve the best therapeutic outcome of their physical therapy.
To investigate the effect of denervation and subsequent reinnervation on skeletal muscle, a histochemical study was performed on the soleus muscles of rats. Partial denervation was carried out by freezing the sciatic nerve locally, and the change in the nerve and the soleus muscles was examined for 5 weeks. The muscle fiber cross-sectional area of the denervated soleus muscles progressively declined to a minimum 2 weeks after the injury (type I fibers, 1209.1 ± 248.3 μm2; type II fibers, 802.4 ± 126.8 μm2) and began to reverse the decline at 3 weeks. The type II fiber ratios to total fiber of the denervated sides were consistently higher than the control levels, and muscle fibers stained in both acid preincubation and alkaline preincubation were observed. The proportion of type II fibers in the soleus muscles showed an increase and consequently a decrease with a short delay in response to denervation and consequent reinnervation. These data suggest that denervation elicits an alteration in fiber type composition and a reduction in fiber size. The increase of type II fibers seemed to occur in hybrid fibers containing both myosin heavy chains I and II at varying ratios in the same fibers. The reinnervation took the crucial role of recovering from atrophy and composing the integrity of the soleus muscles. However, the ability to generate muscle tension needs a much longer time to recover. This suggests a need to investigate interventions to facilitate the functional recovery of partially-denervated muscle.
In this study, the effect of weightlessness on mechanoreceptors in ACL was investigated in rats with hindlimb suspension. The animals used in the present study were 20 Wistar male rats (weight: 278 ± 16 g). The animals were divided into 2 groups: the Suspension group (n=10, suspended for 4 weeks) and Control group (n=10, non-suspended for 4 weeks). ACL was stained with gold chloride. The frozen section was sliced to be approximately 45 μm in thickness using a cryostat. The tissue preparations were observed through an optical microscope. Based on the criteria proposed by Freeman and Wyke, mechanoreceptor was specified and counted. Four types of nerve endings, Pacinian corpuscle, Ruffini corpuscle, Golgi tendon organ-like receptor, and free nerve ending were observed. In the Susupension group, atypical Pacinian corpuscle, and Ruffini corpuscle were observed. The number of mechanoreceptors were significantly decreased in the Suspension group (median 10) compared with the Control group (median 17) (Mann Whitney U test; Z=-2.65, P<0.01). It might be necessary to perform also to early rehabilitation to prevent the degeneration of mechanoreceptors and take into consideration the nerve control system in the clinical setting.
The objective of this study was to clarify how movement is controlled at gait initiation in order to avoid increasing required coefficient of friction (RCOF) on a low friction floor. We aimed at examining the relationship between RCOF during push off for the second step and movement of the first step. Twelve healthy young adults underwent measurement of ground reaction forces during push off for the second step using a force plate. Movement of the first step was measured with a motion analysis system. Upon initiation of the gait on the low friction floor, frequency and displacement of slips were greatest during push off for the second step. As the step length for the first step decreased, there was a significant decrease in the maximum value of RCOF during push off for the second step. These findings suggest that the step length for the first step is reduced in order to avoid increasing RCOF during push off for the second step.
The purpose of this study was to examine the discriminant and predictive validity of grip strength measurements obtained dynamometrically from patients in acute rehabilitation. Retrospective chart reviews were performed to retrieve information on admission grip strength. That strength was compared to published norms to establish discriminant construct validity. Predictive validity was investigated by analyzing the relationship of grip strength with rehabilitation length of stay (LOS) and discharge self-care function (Functional Independence Measure scores). Wilcoxon signed ranks tests showed that the patients' grip strength was significantly less than normal on both their left (Z=-9.205, p<.001) and right (Z=-10.729, p<.001) sides. Grip strength was a significant but weak predictor of both LOS (Spearman rho=-0.277 to -0.352) and discharge function (Spearman rho=0.360 to 0.382) Multiple regression revealed that grip strength added nothing further to the prediction of LOS or discharge self-care function once admission self-care function was taken into account. This study provides strong support for the discriminant validity of grip strength measurements but only weak support for their predictive validity in acute rehabilitation.
The main symptom of chronic heart failure (CHF) is dyspnea and leg fatigue on exercise, demonstrating a decrease in exercise capacity. However, the precise mechanisms of these symptoms are not fully understood. The existence of a relationship between exercise tolerance and respiratory pattern and muscular strength of legs in patients with CHF has not been demonstrated. In this study, therefore, we measured these parameters to clarify the factors which relate to exercise tolerance in CHF patients. Subjects were fifty-four consecutive patients (37 men and 17 women, mean age 53 years) with CHF who underwent cardiopulmonary exercise testing at our hospital from February 1999 to September 2000. Peak oxygen uptake (peak VO2) and respiratory pattern (TV/RR; tidal volume/respiratory rate) were evaluated. The strength of quadriceps was also measured. The respiratory pattern was weak but significantly correlated with peak VO2 (r=0.27, p<0.05). Maximal isometric strength of quadriceps showed a tendency to correlate with peak VO2 (r=0.25, p=0.06). These findings suggest that exercise intolerance, seen in these CHF patients, is related to both respiratory pattern and the maximal muscular strength of legs.
We reported previously on the necessity of the elderly wearing dentures while they take physical therapy, because of improved maximum muscular strength and agility under biting with dentures compared to without dentures. We assumed that this phenomenon resulted from improved strength of the masseter muscle and occlusal force brought about by wearing dentures. In order to corroborate our assumption, we selected eight elderly subjects (age: 71-98; mean age: 83.9) and measured the soleus H (Hoffman wave) reflex as an index of excitability in the spinal cord motor neuron pool, activity of the masseter muscle, and occlusal force of incisors under biting with and without dentures, so as to examine changes in the measured parameters. The results were that the values measured with dentures were significantly greater than those without dentures. We consider that these data support our assumption.
Background and Purpose: The purpose of this study was to determine the difference in the muscle activities of the Vastus Medialis Oblique (VMO), Vastus Medialis Longus (VML), Vastus Lateralis Oblique (VLO) and Vastus Lateralis Longus (VLL) with internally rotated, neutral, and externally rotated knee joint positions during isometric knee extension strength effort at 60° of knee flexion. Subjects: Seven healthy males, aged 24 to 34 years (29.3 ± 4.1), participated in this study. Methods: The subjects performed isometric knee extension with internally rotated, neutral, and externally rotated knee positions. Electromyographic (EMG) activity was detected using bipolar fine wire electrodes and was recorded from VMO, VML, VLO, VLL and the Adductor Magnus (AM). Results: The normalized integrated EMG (IEMG) of VMO, VML and AM were significantly greater in the internally rotated knee position than in the neutral knee position. The normalized IEMG of the VLO and VLL were not significantly different at each knee position. Discussion and Conclusion: VMO, VML and AM muscle activity may be altered by knee rotation position during isometric knee extension effort.