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Persons with neuromuscular disease (NMD) have progressive weakness and wasting of skeletal muscle, reduced fat-free mass, and increased fat mass relative to healthy control subjects. To test the hypothesis that resting energy expenditure (REE), estimated total daily energy expenditure (TEE), and physical activity patterns are altered in ambulatory adults with NMD, 26 adult men and women with slowly progressive NMD and 19 able-bodied control subjects similar in age and weight were evaluated. REE was measured after an overnight fast by indirect calorimetry, TEE by heart rate monitoring, and body composition by air-displacement plethysmography. REE was not significantly different between NMD and control subjects; however, TEE was significantly reduced in NMD subjects compared with control subjects, respectively (women: 7.8 +/- 1.5 compared with 10.5 +/- 2.8; men: 10.2 +/- 3.6 compared with 12.7 +/- 2.6 MJ/d; P < or = 0.01), indicating that NMD subjects expended less energy in physical activity than did control subjects. NMD subjects also tended toward an increased energy cost of physical activity, particularly at higher activity levels (P = 0.06). Multiple regression analysis indicated that for all subjects combined, adiposity was positively associated with age and TEE and negatively associated with time spent in the active heart rate range and fat-free mass (P < or = 0.0001). This relation did not differ between NMD and control subjects, nor did it differ between men and women. We hypothesize that because of their reduced physical activity and increased adiposity, persons with NMD may be at risk for developing secondary conditions such as cardiovascular disease, hypertension, and diabetes. Copyright (c) 1998 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Extensive research has documented that medical care in the United States is not of optimal quality, meaning that well-established care processes are not consistently provided to the patients who would benefit from them. To assess and improve quality of care, specific measures are needed. The objective of this study was to develop quality measures for electrodiagnostic testing in suspected carpal tunnel syndrome (CTS). We used a variation of the well-established RAND/UCLA Appropriateness Method to develop the measures. A physiatrist and quality measurement experts developed draft measures based on guidelines and literature. Subsequently, in a two-round, modified-Delphi process, a multidisciplinary panel of 11 national experts in CTS reviewed a summary of the evidence and then rated the measures for validity and feasibility. Seven draft measures were developed. The expert panel combined two, modified the others, and then judged all resulting measures to be valid and feasible. The measures cover compelling indications for testing, essential test components when CTS is suspected, skin temperature measurement and normalization, and the appropriate interpretation of test results. These measures define a minimum standard of care for the use of electrodiagnostic tests in suspected CTS and are consistent with recent guidelines developed by the American Association of Neuromuscular and Electrodiagnostic Medicine. Provider organizations, insurance companies, and professional societies can use these measures in efforts to monitor and improve quality of care for this common and disabling condition.

Objective: To determine whether a home-based activity and dietary intervention can increase activity level, reduce caloric intake, and impact positively components of metabolic syndrome in a disabled population., Design: Testing occurred at 3 points during the 6-month intervention period (baseline, 3mo, 6mo) and at 6 months postintervention. Each test point included laboratory testing of anthropometric and metabolic variables and 3 days of home-based activity and dietary monitoring. A personally tailored activity and dietary prescription based on baseline testing was implemented during the 6-month intervention period., Setting: Human performance laboratory of a university and each subject's home., Participants: Twenty adult volunteer ambulatory subjects with several types of slowly progressive neuromuscular disease (NMD)., Intervention: Using a pedometer, subjects were instructed to increase number of steps by 25% over their baseline determined from home monitoring. An individualized dietary prescription was provided focusing on problematic issues identified from the baseline dietary profile., Main Outcome Measures: Body composition, physical activity, dietary intake, energy expenditure, gait efficiency, metabolic variables, and quality of life., Results: At the end of the protocol, mean step count increased approximately 27% above baseline (P=.001) and caloric intake decreased over 300kcal/d (P=.002). Body fat percentage significantly decreased (from 33.3%+/-1.5% to 32.6%+/-1.6%, P=.032). Gait efficiency did not change, and metabolic variables did not show statistically significant improvement, although 2 of the 5 subjects originally meeting the criteria for metabolic syndrome at baseline no longer met the criteria at the end of the intervention period. Six months after completing the protocol, caloric intake remained significantly reduced (P=.02), but although mean step count remained elevated, it was not statistically significant., Conclusions: Using a home-based protocol, people with NMD can increase activity and reduce caloric intake. Although this 6-month program showed positive changes, it was insufficient to affect risk factors associated with metabolic syndrome. It remains to be seen if a program longer than 6 months or a more rigorous program could lead to a reduction in the risk factors associated with metabolic syndrome.

Objectives: To test the hypotheses that (1) people with neuromuscular disease (NMD) have multiple risk factors for cardiovascular disease and diabetes and (2) these risk factors worsen over time., Design: Longitudinal testing with average 2.5-year follow-up., Setting: Human performance laboratory of a university., Participants: Eleven ambulatory volunteers with slowly progressive NMD and 8 able-bodied controls, group-matched for age and body mass index (BMI) at baseline., Interventions: Not applicable., Main Outcome Measures: Percentage of body fat (%BF), physical activity, energy expenditure, blood lipids and glucose, and blood pressure., Results: At baseline, NMD subjects were more obese (37%BF vs 34%BF, respectively) and more sedentary than the controls, spending less time in total activity (144 min/d vs 214 min/d) and in exercise (11 min/d vs 45 min/d). The NMD group also had numerous cardiovascular and metabolic risk factors, with low high-density lipoprotein cholesterol, high BMI, and high triglyceride being the most common. Additionally, 55% of the NMD group satisfied the criteria for metabolic syndrome, versus 0% in the control group. Most parameters did not significantly worsen during the average 2.5-year follow-up period in either group., Conclusions: People with NMD are at high risk for developing chronic diseases resulting from obesity and a sedentary lifestyle. Intervention studies aimed at reducing their risk for such chronic diseases are warranted.

There is currently no gold standard to definitively diagnose carpal tunnel syndrome. It remains a clinical diagnosis supported by characteristic electrodiagnostic abnormalities. Properly performed electrodiagnostic studies should provide the hand surgeon with information regarding severity, progression if a previous study was performed, and a reasonable assurance that concomitant peripheral nervous system abnormalities are not present. Hand surgeons do not need to discern nuances of an electrodiagnostic evaluation; however, the ability to identify state-of-the-art techniques coupled with a thoughtful interpretation by the electrodiagnostician will improve their confidence in using this important diagnostic tool to evaluate carpal tunnel syndrome.

Few studies have examined the effect of pain on the quality of life of individuals with slowly progressive neuromuscular disease (NMD). The purpose of this study was to determine the frequency and extent to which subjects with slowly progressive NMD report pain and the association between pain and health-related quality of life in persons with NMD. The study design was a descriptive, nonexperimental survey. Of a total of 1,432 subjects with slowly progressive NMDs recruited from a university-based NMD clinic and the membership rosters of worldwide NMD support organizations, 859 agreed to participate. The primary measurement tool used was the Medical Outcomes Study SF-36 health survey. Our results indicated that, with the exception of adult spinal muscular atrophy (SMA), the frequency and severity of pain reported in slowly progressive NMDs was significantly greater than levels of pain reported by the general US population and was comparable to pain reported by subjects with osteoarthritis and chronic low back pain. There was a significant correlation between increased pain and lower levels of general health, vitality, social function, and physical role. Pain was moderately associated with increased fatigue, inability to cope adequately with stress, and sleep disturbance. In conclusion, with the exception of adult SMA, the frequency and severity of pain reported in slowly progressive NMDs was significant.

Although the response to intense eccentric muscle contractions is well described in normal subjects, concern exists about possible untoward effects in persons with myopathic diseases. We investigated 14 subjects with slowly progressive muscular dystrophies including myotonic muscular dystrophy (n = 9), facioscapulohumeral dystrophy (n = 2), limb-girdle syndrome (n = 2), and Becker muscular dystrophy (n = 1). Control subjects consisted of 18 able-bodied persons. Subjects performed two sets of eight maximal-effort eccentric repetitions of the elbow flexors, with measurement of maximal concentric strength, serum creatine kinase, resting and flexed arm angle, arm circumference, and soreness at days 0, 3, and 7. Although the myopathic group had less initial strength, both groups demonstrated a similar response to the protocol over 7 days. Both groups had a significant rise in serum creatine kinase, which was still elevated at 7 days (P < 0.05). The control group demonstrated a slightly greater injury response in terms of soreness, resting and flexed arm angles, and arm swelling. Both groups of subjects appeared to respond similarly to an acute bout of eccentric contractions. However, the potential long-term effects of this type of exercise in persons with myopathic diseases remains unknown., (Copyright 2001 John Wiley & Sons, Inc.)

An appropriate orthosis can improve the function of a patient with peripheral neuropathy. It is crucial to be cognizant of the patient's goals, concomitant medical conditions, cosmesis, comfort, and functional deficits. In addition, a close working relationship with an orthotist will ensure a successful orthotic prescription.

The purpose of the study is to further assess the usefulness of short TI (time to inversion) recovery (STIR) magnetic resonance imaging (MRI) in detecting denervation of skeletal muscle compared to needle electromyography (EMG). Ninety subjects with clinical evidence of peripheral nerve injury or radiculopathy underwent STIR MRI and EMG of the affected limb. In 74 (82%) of these subjects, a positive correlation was found between STIR MRI and EMG (P < 0.009). STIR MRI has a relative sensitivity of 84% and specificity of 100% for detecting denervation. A subset of 28 subjects underwent quantitative assessments of signal intensity ratio (SIR) from the STIR MRI. The rank order correlation coefficient between the SIR and abnormal spontaneous activity on EMG was 0.70 (P < 0.001). Increased signal intensity on STIR MRI corresponds closely with spontaneous activity on EMG in denervated muscle. Although less sensitive than EMG in detecting muscle denervation, STIR MRI may be a useful adjunctive diagnostic tool in this setting., (Copyright 2000 John Wiley & Sons, Inc.)

Objectives: To determine the test-retest reliability of selected simulated work performance tasks in persons with neuropathic and myopathic weakness and control subjects, and the association between muscular performance during these work tasks and conventional isolated muscle group testing., Design: Measurement of three tasks performed on a work simulation device on two different days separated by 1 week. Associations between work task performance and previously reported strength measures in six muscle groups by hand-held dynamometry (HHD) were examined., Setting: Human performance laboratory of a university., Participants: Convenience sample of ambulatory outpatients with hereditary motor and sensory neuropathy, type I (n = 9), myotonic muscular dystrophy (n = 10), and able-bodied controls (n = 11)., Main Outcome Measures: For work simulation, isokinetic peak torque and total work; and for HHD, maximal isometric torque., Results: Mean between-session differences for work simulation tasks ranged from -11% to +4% for peak torque and from -12% to +12% for total work; test sessions did not differ significantly for either patient or control groups. All groups had between-session intraclass correlation coefficients usually >.80, indicating good consistency. In general, correlations between peak torque during work simulation and HHD were strongest in the control group., Conclusion: Persons with neuromuscular weakness reliably performed the simulated work tasks examined in this investigation. Work simulation tasks may be a useful tool to assess muscular performance in persons with neuromuscular weakness.

Evidence suggests that individuals with DMD have reduced skeletal development, including decreased linear growth and bone mineral density, compared to normal subjects. Despite their reduced muscle mass, a high percentage of DMD patients are overweight. Body composition measurements can assist with monitoring changes in fat mass and skeletal muscle mass as the disease progresses. Weight management in overweight DMD patients is indicated because excess adiposity burdens mobility and breathing, but only one study in two DMD patients has documented that weight reduction can be done safely. In the latter stages of the disease most DMD subjects become underweight because of an acceleration in skeletal muscle protein degradation relative to its synthesis. Studies of energy, protein and branched chain amino acid supplementation in DMD have yielded promising but inconclusive results, and more well-designed studies are needed in this area. Although there is currently no cure for DMD, studies on the role of nutritional therapy in increasing the quality of life in these patients are urgently needed. Studies in adults with various SP-NMDs indicate a reduction in fat-free mass and an increase in fat mass relative to controls. The newly developed method of air displacement plethysmography for measuring body composition is ideally suited for SP-NMD subjects because it requires very little effort and the measurement procedure is relatively fast. Dual energy x-ray absorptiometry technology has been proposed for distinguishing myogenic from neurogenic SP-NMDs from calculation of the fat-to-lean soft tissue ratio, which is higher in patients with myogenic muscular atrophy. Studies on the energy metabolism of ambulatory SP-NMD subjects indicate that their basal metabolic rate is either similar to or slightly lower than controls, but 24-hour energy expenditure is about 25% lower than controls. This reduction in 24-hour energy expenditure is due to a reduction in physical activity in SP-NMD. Studies examining the roles of energy expenditure, physical activity, and diet in the development of adiposity and risk for secondary chronic diseases in SP-NMD subjects are currently underway.

Persons with hereditary neuromuscular diseases generally lead a sedentary lifestyle, placing them at risk for diseases associated with inactivity and causing weakness, which compounds their primary disease. Although research is lacking in this area, evidence to date suggests that this population may benefit from both strengthening and aerobic fitness training programs. Overwork weakness has not been demonstrated in controlled trials of exercise, but clinicians need to be prudent in their recommendations, encouraging alternating periods of physical activity with scheduled rest. Future investigations should focus on the primary symptom of fatigue, and quantify changes in the ability to work and participate in physical activities as outcome measures of an exercise program.

Objective: To determine test-retest reliability of hand-held dynamometry (HHD) in measuring strength of persons with neuropathic weakness., Design: Intratester and intertester reliability of HHD-measured strength over a 7- to 10-day period. In addition, HHD knee strength was compared with criterion standard of fixed dynamometry (FD)., Setting: Human performance laboratory of a university., Participants: Convenience sample of ambulatory outpatients with Hereditary Motor and Sensory Neuropathy, Type I (HMSN) (n = 10) and able-bodied controls (CTL) (n = 11)., Main Outcome Measure: Maximal isometric torque., Results: Intratester intraclass correlation coefficients (ICCs) were high, generally ranging from .82 to .96 for HHD- and FD-measured strength for both HMSN and CTL groups. There were no significant differences between sessions for HHD-measured strength, while FD-measured strength was only significantly different for knee extension (p < .01). Intertester reliability was generally good for both HHD- and FD-measured strength, with ICCs ranging from .72 to .97 for HMSN and CTL groups. Exceptions were knee extensors and ankle dorsiflexors for the CTL group. Knee extensor strength was significantly lower measured by HHD compared with FD (p < .01), but knee flexor strength was similar for the two methods., Conclusion: HHD appears to be a reliable method to measure maximal isometric strength in persons with neurogenic weakness, and may be useful to quickly and objectively evaluate strength in the clinical setting.

A 30-year-old male with hereditary motor and sensory neuropathy, type I (HMSN I), presented with asymmetric weakness of finger extension and radial deviation with left wrist extension, previously felt to be a manifestation of the peripheral neuropathy. Nerve conduction studies confirmed HMSN I; however, needle EMG revealed marked, ongoing axonal loss in muscles innervated by the left posterior interosseous nerve (PIN) only. At surgery there was focal fusiform swelling in the PIN at exit from the supinator muscle, compatible with localized hypertrophic neuropathy, which has not been reported before in HMSN I. A concomitant focal mononeuropathy should be considered in cases of hereditary neuropathy with marked asymmetry of weakness.

Objective: Poor cardiorespiratory endurance is a common finding in neuromuscular disease (NMD), and the capacity of such patients to respond to aerobic training is unclear. This study was conducted to determine if a 12-week walking program results in increased aerobic capacity in slowly progressive NMD subjects, whether such a program is safely tolerated, and whether such patients can adhere to a self-monitored, home-based training program., Design: Before-after trial., Setting: Subjects' homes., Patients: A cohort of 8 slowly progressive NMD subjects (4 men, 4 women) followed in the neuromuscular disease clinic participated (age, 36.6 +/- 8.0 yrs; ht, 170 +/- 11 cm; wt, 74.3 +/- 19.0 kg) (Mean +/- SD)., Intervention: Subjects walked 15 to 30 min 3 to 4 days a week at 50% to 60% of their heart rate reserve., Main Outcome Measures: Resting, submaximal, and peak heart rates, systolic and diastolic blood pressures, oxygen uptake, and peak power output., Results: Graded exercise testing to volitional fatigue using a semirecumbent cycle ergometer before and after the training program found significant decreases in submaximal heart rate by 7 +/- 3 beats/min (Mean +/- SEM) (95% CI = -23 to 9) (p = .046) and submaximal systolic blood pressure by 11 +/- 4 mmHg (95% CI = -31 to 9) (p = .019), and nonsignificant increases in peak power output and VO2., Conclusions: These results suggest that moderate-intensity aerobic exercise training is well tolerated and may provide modest improvement in aerobic capacity in slowly progressive NMD subjects.

A 12-week high resistance home exercise program was completed by 10 subjects with slowly progressive neuromuscular diseases (NMD) and 6 normal control subjects (CTL). After evaluating baseline maximal isometric and isokinetic strength of the elbow flexors and knee extensors, subjects completed the home program using adjustable ankle and wrist cuff weights. One side of the body was randomly chosen for exercise. Subjects initially performed 1 set of 10 repetitions on 3 days a week and gradually increased to 5 sets of 10 repetitions on 4 days a week. The NMD group demonstrated significant (p < 0.05) gains in several knee extension isokinetic strength measures but loss of elbow flexion eccentric peak torque and work per degree. The CTL group demonstrated significant gains in all measures of knee extension strength, with improvement of elbow isokinetic eccentric work per degree as well. There was evidence of cross training to the nonexercised limbs for both groups. A high resistance training program, although well tolerated in NMD subjects with mild to moderate weakness, may cause some deleterious effects to diseased skeletal muscle. A high resistance training program appears to offer no advantage over a moderate resistance training program in this population.

Serial measurements of muscle strength of 34 muscle groups were obtained for up to a seven-year period using manual muscle testing (MMT) in a group of 63 boys (mean age = 11.5 years) with Duchenne muscular dystrophy (DMD) not using lower extremity bracing or corrective surgery for ambulation, in order to define the natural course of strength loss and its relation to anthropometric variables and ambulatory status. When correlating the first MMT assessment of each patient with age, strength was found to decrease linearly (-0.26 +/- 0.30 MMT units/year) with time until approximately age 14 when a marked decrease in progression was noted (-0.06 +/- 0.03 MMT units/year). Analyzing individual patients longitudinally yielded a similar rate of strength loss. The average muscle score was 3.0 MMT units at the point of full-time wheelchair use. The marked decline in MMT deterioration around age 14 may be an important consideration when assessing the efficacy of therapeutic interventions in adolescent boys with DMD.

A 12-week moderate resistance exercise program was performed by 27 patients with slowly progressive neuromuscular diseases (NMD) and 14 control subjects (CTL) in order to determine safety and efficacy of a strengthening program. A 3-day per week submaximal regimen of home exercise using ankle and wrist weights and hand grip exerciser was prescribed. One side of the body was randomly chosen for exercise. Subjects were tested for maximal isokinetic and isometric strength at baseline and after weeks 4 and 12 of the training protocol, and the prescribed amount of work was gradually increased throughout the program. Both the NMD and CTL groups demonstrated significant (p < .05) increases in most strength measures. Both groups responded similarly to the exercise program, and strength gains did not significantly differ between the exercised and nonexercised limbs in either group. This study provides evidence that a 12-week submaximal strength training program is practical and safe in slowly progressive NMD and produces moderate improvement in measured strength.

Phrenic nerve and diaphragmatic dysfunction has been assumed to be the cause of respiratory failure in hereditary motor and sensory neuropathy, type 1 (HMSN I). In order to determine the relationship between phrenic nerve and pulmonary function in this disease, 25 patients underwent a 4-step evaluation process consisting of: (1) bilateral phrenic nerve conduction study; (2) median, peroneal, and tibial motor conduction studies; (3) measurement of forced vital capacity (FVC) and maximal inspiratory and expiratory pressures (MIP, MEP); and (4) pulmonary-focused history and physical. Phrenic nerve motor latency was abnormally prolonged in 22 of the 23 (96%) subjects when a response was obtained. All had slowed velocity or absent peripheral motor conduction responses. Vital capacity was abnormally reduced in 6 of the 25 (24%) subjects. Eight (32%) had an abnormally reduced MIP, while 19 (76%) had an abnormally reduced MEP. Only 2 (8%) subjects had clinical evidence of pulmonary dysfunction. None of the dependent variables (FVC, MIP, MEP, peripheral nerve conduction, or clinical examination) correlated with phrenic nerve latencies. Although phrenic nerve latencies are markedly prolonged in HMSN I, these values are not useful in predicting respiratory dysfunction.