AbstractTwenty-eight haemodialysis patients were randomized to L-carnitine, 2 g i. v. three times a week, and saline over a 6-week period. No obvious deficiency of carnitine was found in vastus lateralis with a median value of 12.9 mmol/kg dry weight; range 6.2-21.4. Female patients had lower total plasma carnitine compared to female controls, p<0.002, whereas no decrease was found in males. No relationship was found between muscle and total plasma carnitine. After carnitine administration the muscle carnitine level increased about 60%, p<0.01, and the total plasma carnitine level more than tenfold, whereas the initially high degree of acylation decreased, p<0.02. Maximum dynamic muscular strength was reduced with a mean value of 44% compared with healthy controls. Total metabolic activity of isolated skeletal muscle fibres, measured as heat production with a new technique using a perfusion microcalorimeter, showed a median value of 0.40 mW/g, 2 5% lower than normal, p<0.02. Carnitine administration had no effect on several different tests of muscular function. Neurophysiologically, discrete improvements in the temperature responses were recorded, but no changes in sensory and motor nerve conduction velocities or in vibration thresholds were noted. No symptomatic improvement was observed even in patients with the lowest carnitine levels prior to treatment. Our data do not support the hypothesis that carnitine deficiency contributes to muscle and nerve dysfunction in patients on chronic haemodialysis.Key Words: Carnitinehaemodialysismuscle functionmuscle metabolismnerve function
420 medical secretaries took part in a cross-sectional study at examining the prevalence of musculoskeletal disorders as well as the relationship between neck and shoulder pain and possible risk factors. Sixty-three percent had experienced neck pain sometime during the previous year and while 15% had suffered almost constant pain 32% had experienced neck pain only occasionally. Shoulder pain during the previous year had been experienced by 62%, 17% had suffered almost constant pain while 29% experienced pain only occasionally. Fifty-one percent had experienced low back pain. Age and length of employment were significantly related to neck and shoulder pain. Furthermore, working with office machines 5 hours or more per day was associated with a significantly increased risk for neck pain (OR 1.7), shoulder pain (OR 1.9) and headache (OR 1.8). Finally, a poorly experienced psychosocial work environment was significantly related to headache, neck, shoulder and low back pain. The results of this study suggest that work with office machines as well as the psychosocial work environment are important factors in neck and shoulder pain.
Abstract Abstract This corss-sectional study exmaines the relationship between healthy lower and psychosocial and physical factors in a random sample of 1773 male construction workers. Infoamtion on lower back status, lifestyle habits, stress, psychosomatic and psychological symptoms, psychosocizal demands and resoruces and physical workload were collected by means of a postal questionnaire. Measures of psycholocial and physical factors were based on factor analysis of the data. The criterion variable ‘healthy lower back’ (HLB)—no lifetime history of low back pain—proved to be valid compared with an interview and a physical examination. A total of 216 workers (12%) reported HLB. The prevalance rate decreased significantly with increasing age. The prevalence rate of HLB was 6% among workers reporting high stress levels. It was postively influenced when there was a balance between demands and resoruces. A low level of physical workload also increased the prevalence rate of HLB. When age, lifestyle and physical factors were kept constant in a multivariate analysis high scores on the discretions index and low scores on eh psychosomatic, psychological and stress indices cosntributed significantly to an increase prevalence rate of HLB. Key Words: Healthy lower backsLow back painStessWorkloadJob demand
The aim of this prospective study was to follow the pain and discomfort among dentists in the Public Dental Service in Malmöhus District and the Municipality of Malmö. In this investigation 311 dentists, who had answered questionnaires in 1987 and in 1990, took part. The prevalence of musculoskeletal pain and discomfort had increased, except the lower back pain and headache. However, the only significant difference was found with respect to the shoulders. As in 1987, female dentists had also in 1990 a higher prevalence of pain and discomfort in the neck and shoulders than their male colleagues. Of the 311 dentists, 262 had symptoms both in 1987 and in 1990. In 1987 forty-nine dentists were free of symptoms, while 24 of them reported symptoms in the locomotor system in 1990. Of the 262 dentists with symptoms in 1987 twenty-four were without symptoms at the follow-up in 1990. The aim of the investigation was also to study the influence of some ergonomic factors on the course of symptoms. However, these ergonomic variables showed a low predictive value for recovery or for the development of pain and discomfort in the locomotor system.
The aim of the investigation was to compare dentists with and without occupational cervico-brachial disorders with regard to some psychosocial variables (work environment, personal harmony and life-satisfaction) and professional position. The investigation is based on a questionnaire sent to 143 randomly selected official dentists in Malmöhus District and the Municipality of Malmö. Of these, 96 dentists had symptoms while 47 had not. Dentists with symptoms showed less satisfaction with their work environment than dentists without. Those with symptoms experienced their work load as being more unsatisfactory, were more burdened by anxiety, had poorer psychosomatic health and less confidence in the future than dentists without symptoms. These differences were significant between the groups. It was found that specialists, both with and without cervico-brachial symptoms, were more satisfied with their psychosocial work environment than general practitioners, especially regarding their personal control over their work and the stimulation of their work. The specialists also had more self-confidence and experienced less anxiety than general practitioners and head dentists.
The aim of the investigation was to compare dentists with and without occupational cervicobrachial disorders with regard to the mobility of the neck and shoulders and the static endurance of the shoulder muscles. Further, differences in working position and the task performance on a stimulated case were to be analysed. The investigation was carried out during a visit to the workplace of 143 dental officers in the Public Dental Service in Malmöhus District and the Municipality of Malmö. Of these dentists, 96 had signs of cervico-brachial disorders and discomfort while 47 had not. The ergonomic examination showed, that significantly more dentists without symptoms of pain applied a wedge cushion under the upper part of the back of the patient to get an optimum view (p less than 0.05). It was also found that significantly more dentists without symptoms were aware of and utilised the naturally arising pauses in their work than dentists with pain and discomfort. Further dentists with cervico-brachial disorders kept their head sidebent and rotated to a greater extent than dentists without symptoms (p less than 0.01). No significant difference was found between the two groups concerning mobility of the neck and shoulders. Significant differences were found between women with and without cervico-brachial systems.
SummaryThe intrinsic viscosity of hyaluronic acid synthesized in tissue cultures of synovial membranes of the human knee joint was studied. Tissue material from cases of rheumatoid arthritis as well as from «non-rheumatic» cases was cultivated. The main principle was to cultivate the same tissue material in the presence of normal serum and in the presence of rheumatoid arthritic serum. Then the intrinsic viscosity of the supernatants was determined each week during 3 weeks of cultivation. The results indicate that the presence of rheumatoid arthritic serum did not appreciably influence the intrinsic viscosity of the hyaluronic acid synthesized by the tissue cultures studied. Possibly early selection of the cells is to be taken into consideration.
The purpose of this study was to investigate the reliability of repeated measurements and a possible learning or tiring process in single-limb stabilometry and one-leg hop test. An additional purpose was to study the correlation between different stabilometric variables. Seventy-five healthy subjects were examined twice with a median interval of 7 d, and with three consecutive measurements on each occasion. Single-limb stabilometry and one-leg hop test were found to have high reliability (ICC r = 0.68-0.83 and 0.96, respectively). The correlation between consecutive measurements was acceptable to high in stabilometry (r = 0.42-0.90, P = 0.002-P < 0.001) and high in the one-leg hop test (r = 0.91-0.97, P < 0.001). A learning process over time was observed. The correlation between the stabilometric variables was high (r = 0.73-0.95, P < 0.001).
Summary The effects on maximal isometric trunk muscle strength and endurance after wearing a soft heat-retaining lumbar belt or a weightlifter's belt were studied. The soft belt (SB) study group comprised 12 construction workers with healthy backs, and the weightlifter's belt (WB) group comprised 24 construction workers with current or previous low back pain. The strength and endurance measurements were performed before the start of belt use, and after 1 and 2 months. The SB group increased the trunk flexor strength by 13% (p ≤ 0.01) after 2 months. The WB group increased the trunk flexor strength and endurance by 12% and 29%, respectively (p ≤ 0.001). No significant decrease of trunk muscle strength and endurance was found at the end of the follow-up period.