Manual Muscle Research Articles

Intensive care unit-acquired weakness and the COVID-19 pandemic: A clinical review.

Patients with severe cases of coronavirus disease 2019 (COVID-19) often become critically ill requiring intensive care unit (ICU) management. These individuals are at risk for developing ICU-acquired weakness (ICUAW), a multifactorial condition in which polyneuropathy, myopathy, and/or disuse muscle atrophy result in motor weakness. This weakness is thought to contribute to the long-term functional disability frequently observed in survivors of critical illness. This review discusses the current evidence regarding the epidemiology, pathophysiology, evaluation, risk factors, and rehabilitation-specific management of ICUAW in patients with COVID-19. Because of the novelty of COVID-19, the exact prevalence of ICUAW is not well delineated among COVID-19 patients. However, ICUAW has been reported in this population with retrospective studies showing weakness occurring in up to 45.5% of patients with severe COVID-19. There are multiple risk factors for developing ICUAW among COVID-19 patients, including premorbid health status, sepsis, multiple organ failure, mechanical ventilation, immobilization, neuromuscular blockade, corticosteroid use, and glycemic control. ICUAW is more likely to occur after prolonged mechanical ventilation and long hospital stays and can be diagnosed with manual muscle and electrodiagnostic testing. Although the long-term sequela of COVID-19 after ICU stays is not fully studied, increasing evidence indicates significant risk for this population developing long-term functional impairments. Establishing postacute rehabilitation programs for COVID-19 survivors will be important for recovery of endurance, mobility, and function.

Function, strength, and muscle activation of the shoulder complex in Crossfit practitioners with and without pain: a cross-sectional observational study

BackgroundThe shoulder joint is the most commonly injured joint in CrossFit practitioners, because of the high intensity and loads associated with this sport. Despite the large number of clinical cases, there is a shortage of studies that investigate influence of biomechanical aspects of upper limbs' injuries on CrossFit practitioners. This study hypothesized that there would be a difference in function, strength, and muscle activation between Crossfit practitioners with and without shoulder pain.MethodsWe divided 79 Crossfit practitioners into two groups according to whether they reported pain (n = 29) or no pain (n = 50) in the shoulder during Crossfit training. Muscle function, strength, and activation were assessed using the Disability Arm, Shoulder and Hand function questionnaire, Upper Quarter Y Balance Test and Closed Kinetic Chain Upper Extremity Stability Test shoulder tests, isometric muscle strength assessment by manual dynamometry and muscle activation by surface electromyography and pain report.ResultsThe function based on questionnaire was associated with pain (p = 0.004). We observed a statistically significant difference between the two groups only in the surface electromyography activity of the lower trapezius, and in the variables of shoulder pain and function (p = 0.038).ConclusionCrossfit practitioners with shoulder pain occurring during training showed good function and stability of the shoulder joint, but there was a reduction in the activation of stabilizing muscles, especially the lower trapezius.Trial registration Registro Brasileiro de Ensaios Clinico (Brasilian National Registry) with the ID: RBR-2gycyv.

A case of cerebellar hemorrhage in a patient with severe dengue

Background: Degue is the most rapidly spreading mosquito-borne viral infection in the world with various symptoms and clinical presentation. Neurological complication of dengue is rare (0.5 to 7.4%) and its pathophysiological basis of is not fully understood. Data on cerebellar hemorrhage as a complication of severe dengue is rare. Case Description: This is a case of a 25 y old female, household helper presented with a 5 d history of fever, headache, nausea, vomiting and diarrhea. She consulted a physician, diagnosed was acute gastroenteritis, advised supportive care. Workups showed leukopenia, thrombocytopenia, positive dengue NS1Ag. She was hydrated intravenously at home. In 2 d, platelet count further decreased and transaminases were elevated. On the 5th day of illness, fever and diarrhea resolved, but was noted disoriented. At the ER, vital signsBP 100/70 mmHg, CR 78, RR 26, temperature 36.5C, GCS13 (E3V4M6) with petechiae on both upper extremities. Manual muscle and sensory testing were normal but unable to do finger to nose test, no meningeal and Babinski signs. Repeat workups showed leukocytosis (22.70 x 109/L), thrombocytopenia (47.00 x 109/L). She was hydrated with PNSS and started on cefepime and moxifloxacin to cover for a possible pneumonia. She was noted to be unresponsive and was intubated. ET secretion was frothy. Other workups: 12LECG sinus tachycardia with anterior wall ischemial; chest X-ray pulmonary edema; cranial CT scan showed cerebro-cerebellar edema with uncal herniation, non-communicating hydrocephalus with possible subarachnoid hemorrhage. Her blood pressure decreased requiring vasopressors. She was to be transfused with platelet concentrate, when she had cardiac arrest and attempted resuscitation 3 times. Patient eventually expired. Post-mortem examination showed pulmonary congestion (right lung 700 g, left lung 750 g); pleural effusion (right 300 mL light red, thin fluid), cerebellar hemorrhage and gastric pinpoint hemorrhages. Discussion: Prevalence of hemorrhage on dengue, especially in the central nervous system, especially in the cerebellum is rare. Further studies may be done to determine certain risk factors that may be predict such complications. Conclusion: We were able to present a case of severe dengue presenting with cerebellar hemorrhage and circulatory collapse and exemplified that these cases possessed high mortality despite early diagnosis.

Patient insights on living with idiopathic inflammatory myopathy and the limitations of disease activity measurement methods \u2013 a qualitative study

BackgroundThe idiopathic inflammatory myopathies (IIMs) are chronic autoimmune conditions, typically resulting in proximal muscle weakness and impacting upon quality of life. Accurate measurement of IIM disease activity is imperative for appropriate medical management and carrying out valid clinical trials. The International Myositis Assessment and Clinical Studies Group (IMACS) “Disease Activity Core Set Measures” are the current gold-standard of IIM disease activity assessment. Anecdotally, patients with an IIM report that the IMACS Core Set Measures and other available methods do not necessarily capture their perceived disease activity. Investigating the patient experiences of living with an IIM and their views on the accuracy of the IMACS Core Set Measures will provide valuable insights for both clinical and research purposes.MethodsEighteen interviews with patients with an IIM were carried out and analysed thematically, using a grounded theory approach. Experiences on living with an IIM and perceptions on the accuracy of disease activity measurement methods were explored.ResultsInterview analysis revealed four themes: 1) fatigue, 2) pain, 3) day-to-day symptom variation, 4) limitations of creatine kinase levels and manual muscle testing.ConclusionsThis study has provided valuable insights into patient experiences of living with an IIM. Aspects of IIM disease activity perceived not to be wholly measured by the IMACS Core Set Measures have also been identified. These findings have implications for future IIM clinical care and research, in particular providing justification for research into pain, fatigue and symptom variation.

Impact of Physical Exercise on Depression and Anxiety Symptoms, Quality of Life and Muscle Strength in the Elderly

Background. Mood disorders affect the quality of life and functional abilities in older people. The elderly are often physically inactive, suffering from chronic diseases. It is not clear if physical exercise improves quality of life and motor function in patients with depressive and anxiety symptoms.The aim. To determine the impact of physical exercise on depression and anxiety symptoms, quality of life and muscle strength in the elderly.Methods. Eighteen individuals over 60 years of age were studied. Subjects were evaluated before and after physical exercise interventions using the following assessment methods: Hospital Anxiety and Depression Scale; Short version of the WHO Quality of Life Questionnaire WHOQOL-BREF; Manual muscle testing.Results. Subjects had decreased scores for depression, anxiety, and general psychoemotional area, improved quality of life scores in all areas, and improved muscle strength in all groups studied. The percentage change after exercise intervention was better in functional movements in those who rated their physical health worse before exercise. The percentage change in subjects who rated psychological health better before physical exercise intervention was better in the area of anxiety and overall psychoemotional status than in those who rated it worse. In the area of social relations, the percentage change did not differ between the groups (p < 0.05).Conclusion. After eight weeks of physical exercise intervention in the elderly, depression and anxiety rates were reduced, and quality of life and motor functions were improved in the subjects.Keywords. Physical exercise, depression and anxiety, the elderly, quality of life, motor functions.

Follow-up results of myositis patients treated with H. P. Acthar gel

Idiopathic inflammatory myopathies (IIM) are a group of autoimmune diseases characterized by proximal muscle weakness. H. P. Acthar gel [repository corticotropin injection (RCI)] is a formulation of adrenocorticotropic hormone and has been approved by Food and Drug Administration for use in IIM; however, literature is limited. In this study, we report longitudinal follow-up of myositis patients treated with RCI. Patients with refractory IIM who were enrolled in the prospective, open-label RCI trial were included in this study. The post-trial follow-up period was 6 months with assessments every 2 months, which included myositis core set measures including extra-muscular global, muscle and patient global disease activities, HAQ, and manual muscle testing. Two patients were lost to follow-up after finalization of the trial, and the remaining eight patients were enrolled in the follow-up study. One patient remained on RCI after the trial. In the follow-up period, four of eight patients had flare at on average 4.1 months after the RCI trial. Among the patients who flared, three required an increase in prednisone. One patient was restarted on RCI at 5.5 months, but had minimal improvement after 3 months. Four patients who remained stable continued to satisfy criteria for the definition of improvement through the 6-month follow-up. However, none showed any further improvement in the primary or secondary efficacy outcomes after the initial RCI trial. To our knowledge, this is the first study reporting the follow-up results of patients treated with standard dose and duration of Acthar. We believe that our study will provide the basis for the development of future randomized RCI trials in IIM.

Clinical efficacy of tacrolimus for treating myasthenia gravis and its influence on lymphocyte subsets

BackgroundThis study aimed to determine the clinical efficacy and effects of tacrolimus in treating myasthenia gravis (MG). MethodsA total of 45 outpatients and inpatients were divided into a tacrolimus group (n=15) and non-tacrolimus group (n=30): those in the former group were treated with 3mg/day of tacrolimus for 24 weeks, while those in the latter (control) group took other immunosuppressants (prednisone, azathioprine combined with prednisone). Each group was evaluated at weeks 4, 8, 12, 16, 20 and 24 by Myasthenia Gravis Foundation of America Quantitative Myasthenia Gravis (MGFA-QMG) Test, activities of daily living (ADL) profiles, and manual muscle (MMT) and fatigue tests. Dynamic changes in CD4+CD25+high cells were tested by flow cytometry. Inflammatory cytokines were also evaluated in the tacrolimus group. ResultsEfficacy index scores decreased significantly compared with baseline at every test week in both groups (P<0.01), although improvements were more evident with than without tacrolimus treatment (F=9.312, P<0.01 vs. F=24.551, P<0.01 and F=10.710, P<0.01). At week 24, peripheral blood CD4+CD25+high T cells with tacrolimus decreased significantly (P<0.01), but increased significantly without tacrolimus (P<0.01). During treatment, CD19+BAFF-R B cells in peripheral blood decreased in both groups (P<0.05). Interferon (IFN)-γ concentrations in peripheral blood also diminished significantly with tacrolimus (P<0.01). ConclusionA relatively low dose of tacrolimus can affect multiple immune-system targets and, thus, can treat MG effectively in terms of both clinical symptoms and immunological responses.

Efficacy of Whole Body Vibration on Strength of Calf and Quadriceps Muscles Post Burn

AbstractBackground: This study was conducted to evaluate the efficacy of whole-body vibration on strength of calf and quadriceps muscles post burn.Patients and Methods: Thirty patients (male and female) had second degree burn of lower limb with surface area about (20-35%) suffering from weakness of quadriceps and calf muscles. Their ages ranged between (20-35) years were participated in this study. The study conducted during the period between March and July (2017) at Makka Hospital and Al-Nada Hospital.They were assigned randomly into two Groups (A and B) equal in number: Group (A) Fifteen patients had received vibration training on vibration platform plus traditional physical therapy program (eight weeks, three times a week). Group (B) fifteen patients had received the same traditional physical therapy program only.Evaluation: Evaluations of both Groups (A and B) were done before starting the treatment and at the end of study after eight weeks using hand held dynamometer and manual muscle test.Treatment: Started immediately post wound closure. This study showed a statistically significant increase in calf and quadriceps muscle strength after eight weeks of receiving whole body vibration in addition to home based physical therapy program, compared with Group B who received traditional physical therapy program only.Results: Comparison between both Groups (A and B) before starting the study revealed that there was a statistically nonsignificant difference in calf and quadriceps muscle force between them. At the end of the study, there was a significant increase in the muscle force in the study group (Group A) compared with control groups (Group B).Conclusion: Participation in Whole Body Vibration (WBV) program resulted in a greater improvement in quadriceps and calf muscle strength in adults with healed thermal burn compared to base line values; a WBV program is an effective for strength gain in rehabilitation of burned patients.

To study the effectivenes of cyriax manual therapy versus muscle energy technique in subjects with tennis elbow on pain, grip strength and functional disability

To study the effectivenes of cyriax manual therapy versus muscle energy technique in subjects with tennis elbow on pain, grip strength and functional disability

A comparison study of patient ratings and safety of 32- and 34-gauge insulin pen needles.

Our aims were to compare diabetic patients' evaluations of straight 32- and tapered 34-gauge 4-mm needles for usability and preference as well as the frequency of injection adverse events during insulin self-injection and to analyze the relationship between patients' preferences and their background characteristics including thumb force measured by manual muscle testing. We enrolled 60 insulin-treated patients and measured their maximum thumb force. Patients were randomized into two groups (32- and 34-gauge) with reverse order of needle use: 1week with one type of needle and the next week with the other. The usability of and preference for the needles were measured using the visual analog scale (VAS), and the frequency of injection adverse events was evaluated. Mean maximum thumb strength was 83.5±25.4N, tended to decrease with age and was significantly lower in females than in males. The mean VAS scores regarding smooth insertion and pain during insulin delivery were significantly different, favoring the 34-gauge needle. However, the mean VAS scores regarding ease of pushing an injection button and overall preference showed no significant difference between the two needles. There was no significant difference in the frequency of injection adverse events including breaking needles. Our patients had sufficient thumb force to push the injection button regardless of needle type. Although significant differences regarding smooth insertion or pain during insulin delivery were perceived, there was no difference in overall preference between the two needles, indicating the usability and safety of the two needles are not different in clinical use.

Restrictive lung involvement in facioscapulohumeral muscular dystrophy

Few studies have evaluated the frequency or predisposing factors for respiratory involvement in facioscapulohumeral muscular dystrophy type 1 (FSHD1) and type 2 (FSHD2). We performed a prospective cross-sectional observational study of 61 genetically confirmed FSHD participants (53 FSHD1 and 8 FSHD2). Participants underwent bedside pulmonary function testing in sitting and supine positions, a standard clinical history and physical assessment, and manual muscle testing. Restrictive respiratory involvement was suggested in 9.8% (95% confidence interval 2.4-17.3): 7.5% FSHD1 and 25.0% FSHD2 (P = 0.17). Participants with testing suggestive of restrictive lung involvement (n = 6) were more severely affected (P = 0.005), had weaker hip flexion (P = 0.0007), and were more likely to use a wheelchair (P = 0.01). Restrictive respiratory involvement should be considered in all moderate to severely affected FSHD patients with proximal lower extremity weakness. The higher frequency of restrictive lung disease in FSHD2 seen here requires confirmation in a larger cohort of FSHD2 patients.

Relationships Among Manual Body Functions, Manual Capacity, and Bimanual Performance Using the Prosthetic Upper Extremity Functional Index in Children With Congenital Hand Differences

Most surgical techniques intervene at the level of body functions of the upper limb, aiming to improve manual capacity and activity performance. However, the nature of the relationships among these levels of functioning and evidence for hand function variables predicting performance have scarcely been investigated. The primary aim of this study was to assess aspects of hand function and manual capacity that influence bimanual performance in children with congenital hand differences (CHDs), ranging from surgically corrected polydactyly or syndactyly to radial dysplasia. A secondary aim was to assess whether the number of items on the Prosthetic Upper Extremity Functional Index (PUFI) can be reduced without losing information on bimanual performance in this population. A cross-sectional design was used. One hundred six 10- to 14-year-old children with CHD participated in the study, which was conducted in a university hospital's outpatient clinic. Bimanual performance was evaluated with child self-reports on an adapted version of the PUFI, calculating ease of performance and actual use of the affected hand. Additionally, hand function and manual capacity were assessed. The median score on ease of performance was high, and, on average, the children used their affected hand actively in 97% of all activities. Manual capacity of the nondominant hand and lateral pinch strength of the dominant hand predicted attainment of maximum PUFI scores. Nonmaximum PUFI scores were predicted by opposition strength of the nondominant hand and lateral pinch strength of the dominant hand. In addition, in this patient group, only 6 items of the PUFI explained all variance in PUFI scores. The generalizability of the results is limited by the carefully selected age range. Second, the cross-sectional design of the study limits statements on causality on the relationships found. Children with a CHD generally have good bimanual performance and, on average, perform activities with active use of the affected hand. Therapy directed toward increasing manual capacity and finger muscle strength might assist in improving bimanual performance in children with CHD. Furthermore, the number of items on the PUFI could be reduced from 38 to 6 items in children with CHD.

Rehabilitation for the management of knee osteoarthritis using comprehensive traditional Chinese medicine in community health centers: study protocol for a randomized controlled trial

BackgroundIt is becoming increasingly necessary for community health centers to make rehabilitation services available to patients with osteoarthritis of the knee. However, for a number of reasons, including a lack of expertise, the small size of community health centers and the availability of only simple medical equipment, conventional rehabilitation therapy has not been widely used in China. Consequently, most patients with knee osteoarthritis seek treatment in high-grade hospitals. However, many patients cannot manage the techniques that they were taught in the hospital. Methods such as acupuncture, tuina, Chinese medical herb fumigation-washing and t’ai chi are easy to do and have been reported to have curative effects in those with knee osteoarthritis. To date, there have been no randomized controlled trials validating comprehensive traditional Chinese medicine for the rehabilitation of knee osteoarthritis in a community health center. Furthermore, there is no standard rehabilitation protocol using traditional Chinese medicine for knee osteoarthritis. The aim of the current study is to develop a comprehensive rehabilitation protocol using traditional Chinese medicine for the management of knee osteoarthritis in a community health center.Method/designThis will be a randomized controlled clinical trial with blinded assessment. There will be a 4-week intervention utilizing rehabilitation protocols from traditional Chinese medicine and conventional therapy. Follow-up will be conducted for a period of 12 weeks. A total of 722 participants with knee osteoarthritis will be recruited. Participants will be randomly divided into two groups: experimental and control. Primary outcomes will include range of motion, girth measurement, the visual analogue scale, and results from the manual muscle, six-minute walking and stair-climbing tests. Secondary outcomes will include average daily consumption of pain medication, ability to perform daily tasks and health-related quality-of-life assessments. Other outcomes will include rate of adverse events and economic effects. Relative cost-effectiveness will be determined from health service usage and outcome data.DiscussionThe primary aim of this trial is to develop a standard protocol for traditional Chinese medicine, which can be adopted by community health centers in China and worldwide, for the rehabilitation of patients with knee osteoarthritis.Trial registrationClinical Trials Registration: ChiCTR-TRC-12002538

80. Comparison of manual and probabilistic muscle categorizations based on needle electromyography signals

80. Comparison of manual and probabilistic muscle categorizations based on needle electromyography signals

IMPACT OF POST-POLIO-RELATED FATIGUE ON QUALITY OF LIFE

To assess the impact of post-polio-related fatigue on quality of life. Cross-sectional case control study. Patients without additional health problems that may induce fatigue were selected from among 82 polio survivors. Twenty-six patients with post-polio syndrome and 10 without post-polio syndrome were included. Control group consisted of 30 healthy volunteers. We assessed presence and severity of fatigue by Fatigue Severity Scale, quality of life by Nottingham Health Profile, and impact of fatigue on quality of life by Fatigue Impact Scale. Leg muscle strength was measured by manual muscle testing. Strength of leg muscles showed no differences between the patients with and without post-polio syndrome. Patients with post-polio syndrome reported significantly higher levels of fatigue and reduced quality of life compared with both patients without post-polio syndrome and control group. Fatigue Impact Scale revealed that fatigue did not significantly impair mental health, but had a negative impact especially on physical and psychosocial functioning of the patients with post-polio syndrome. Post-polio-related fatigue seems to be an important factor for further impairment of quality of life in polio survivors.

Breast cancer-developing clinical guidellines for England and Wales

Gagnon C, Mathieu J, Jean S, Laberge L, Perron M, Veillette S, Richer L, Noreau L. Predictors of disrupted social participation in myotonic dystrophy type 1.To identify personal and environmental predictors of the most disrupted participation domains in people with myotonic dystrophy type 1 (DM1).Cross-sectional study.Outpatient neuromuscular clinic.Adults (n=200; 121 women), age 18 years or older (mean age, 47y), with a confirmed diagnosis of DM1 were selected from the registry of a neuromuscular clinic (N=416). Fifty-two participants had the mild phenotype and 148 the adult phenotype.Not applicable.Social participation in mobility, housing, employment, and recreation was assessed with the Life Habits Measure. Disrupted participation was based on whether help was needed in performing most life habits because of incapacities or environmental barriers. Environmental factors were assessed by using the Measure of the Quality of the Environment. Personal factors were assessed with standardized instruments including the Berg Balance Scale, the Krupp Fatigue Severity Scale, and manual muscle testing.A large proportion of participants (45%–61%) reported disrupted participation in all 4 domains. Lower-extremity strength (odd ratios [OR], 15.0–5.5; P<.050) and higher fatigue (OR, 6.0–2.6; P<.05) were present in participants with disrupted participation. With regard to environmental factors, family support (OR, 3.6–2.5; P<.05) and public services (OR, 2.8–2.2; P<.05) were perceived as barriers for participants with disrupted participation in most domains.This study identified personal and environmental factors that may influence the trajectory toward disrupted participation in individuals with DM1. Fatigue, strength, family support, and public services were found to be independent predictors of disrupted participation.

The relation between lower extremity strength and shoulder overuse symptoms: A model based on polio survivors

Objective: To determine the relation between lower extremity weakness and shoulder overuse symptoms among polio survivors. We predicted that individuals with moderate weakness in their leg extensor muscles would use their arms to help compensate for this weakness and would be at high risk for developing symptoms of shoulder overuse.Design: A cohort study of polio survivors recruited from the Einstein-Moss Postpolio Management Program (Philadelphia), the community, and the surrounding region.Setting: A research laboratory at Moss Rehabilitation Research Institute, Philadelphia, PA.Participants: One hundred ninety-four polio survivors. Demographic and medical history data, symptom data, and strength data were obtained for each.Main Outcome Measures: Presence or absence of shoulder symptoms and ratings of pain by visual analogue scale were recorded. Strength was measured using a hand-held dynamometer and manual muscle testing.Results: Shoulder symptoms could be grouped into two distinct clusters based on the type of testing used for assessment. Symptoms elicited by palpation were present in 26% of the subjects and were strongly related to knee extensor strength and weight. These symptoms were more common among women than men (42% and 10%, respectively). Symptoms elicited by resistance tests were present in 33% of the subjects and were seen with equal frequency in both sexes. These symptoms were also related to lower extremity strength, but the specific relationship was not as clear as for the palpation-related symptoms.Conclusions: Lower extremity weakness predisposes individuals to shoulder overuse symptoms. Sex and body weight are contributing factors. These results may be generalized to other populations with lower extremity weakness, including the elderly.

Subjectivity of forces associated with manual-muscle test grades of 3+, 4-, and 4.

This study examined the subjectivity of forces applied by 10 testers during simulated manual-muscle testing. Individual testers were able to modify appropriately the forces they applied for muscle test grades of 3+, 4-, and 4, that is, the forces rose concomitantly with the grades. Testers were consistent between trials in the forces they applied for each grade while testing each specific action. They varied, however, in the forces they applied for each grade during the testing of the two different muscle actions. Moreover, testers differed significantly from one another in the forces they applied for each manual muscle test grade (3+, 4-, and 4). If an individual's strength is to be monitored using manual-muscle testing, grades obtained by a single tester are recommended.

Effect of prednisone on protein metabolism in Duchenne dystrophy

Prednisone improves strength in Duchenne dystrophy and changes the natural history of the disease. We studied the in vivo effects of prednisone (0.75 mg.kg-1.day-1) on muscle and whole body protein metabolism in six patients with Duchenne dystrophy and three patients with Becker dystrophy. Patients were admitted to the Clinical Research Center for study and consumed a constant flesh-free diet. Strength was measured by manual and quantitative muscle testing. Fractional muscle protein breakdown was estimated by the ratio of 3-methylhistidine to creatinine excretion determined in three consecutive 24-h urine collections. Whole body protein kinetics were studied in the postabsorptive state using a primed continuous infusion of L-[1-13C]leucine. Fractional muscle protein synthesis was determined from tracer incorporation into noncollagen muscle protein obtained by needle biopsy. After 6-8 wk of prednisone treatment, average muscle strength increased by 15% (P < 0.04), and 24-h creatinine excretion (an index of muscle mass) increased by 21% (P = 0.002). 3-Methylhistidine excretion decreased by 10%, but the change was not statistically significant. The ratio of 3-methylhistidine to creatinine excretion decreased by 26% (P < 0.04). Fractional muscle protein synthesis and whole body protein synthesis and breakdown did not change significantly. We conclude that the beneficial effect of prednisone on strength in Duchenne dystrophy appears to be associated with an increase in muscle mass, which may be mediated by inhibition of muscle proteolysis rather than stimulation of muscle protein synthesis.

Prednisone in Duchenne Dystrophy

A randomized, controlled trial of daily prednisone was conducted in 99 boys (aged 5 to 15 years) with Duchenne dystrophy to define the time course of improvement and the dose response to treatment. Prednisone at 0.3 mg/kg (n = 33), prednisone at 0.75 mg/kg (n = 34), and placebo (n = 32) were administered for 6 months. Patients were examined using manual muscle and myometry testing, timed functional testing, pulmonary function testing, and laboratory measurements at 10 days, 1 month, 2 months, 3 months, and 6 months of treatment. Boys treated with prednisone had stronger average muscle strength scores, than did boys treated with placebo as early as 10 days after starting therapy. At the 3-month visit, the boys in the group given 0.75 mg/kg of prednisone were significantly stronger than those in the group given 0.3 mg/kg of prednisone, indicating a dose response. At 6 months, significant side effects occurred in the group treated with 0.75 mg/kg of prednisone, including weight gain, cushingoid appearance, and excessive hari growth. Only weight gain was observed in the group taking prednisone at a dose of 0.3 mg/kg. Importantly, no side effects were evident at 10 days or 1 month of treatment, despite improvement in muscle strength and function. We conclude that prednisone produces a rapid increase in muscle strength in patients with Duchenne dystrophy and that this improvement is maximal at a prednisone dosage of 0.75 mg/kg or less.