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This study investigates the relationship between manual muscle test scores (MMT) and quantitative isometric strength measurements (QIS). It also evaluates the implications of that relationship for design of therapeutic trials. Extension and flexion strength at the elbows, hips, and knees of 21 neuromuscular disease patients were tested a total of 26 times utilizing both MMT and QIS testing. Paired data were evaluated with Spearman ranked correlation coefficients, and then QIS was predicted from MMT using Lowess, a consistent form of nonparametric regression. Finally, the implications of the Lowess analysis for designing a therapeutic trial were evaluated. MMT and QIS measurements were significantly correlated in all movements tested. Lowess analysis yielded prediction errors ranging from 16 to 24% of QIS range. Analysis of the sample size needed for a therapeutic trial suggested that a protocol measuring MMT would require more subjects for the same level of statistical significance as a protocol measuring QIS. Since it was not possible to reliably predict QIS values from MMT scores, such conversions are not appropriate for clinical use. This inconsistent relationship between MMT and QIS carries major implications for the design of therapeutic trials. Since therapeutic trials are time consuming, expensive, and most centers do not have large numbers of individuals available, using QIS as an outcome measure is a preferable research design.

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This article reviews the current status of exercise training and contraction-induced muscle-injury investigations in animal models of muscular dystrophy. Most exercise-training studies have compared the adaptations of normal and dystrophic muscles with exercise. Adaptation of diseased muscle to exercise occurs at many levels, starting with the extracellular matrix, but also involves cytoskeletal architecture, muscle contractility, repair mechanisms, and gene regulation. The majority of exercise-injury investigations have attempted to determine the susceptibility of dystrophin-deficient muscles to contraction-induced injury. There is some evidence in animal models that diseased muscle can adapt and respond to mechanical stress. However, exercise-injury studies show that dystrophic muscles have an increased susceptibility to high mechanical forces. Most of the studies involving exercise training have shown that muscle adaptations in dystrophic animals were qualitatively similar to the adaptations observed in control muscle. Deleterious effects of the dystrophy usually occur only in older animals with advanced muscle fiber degeneration or after high-resistive eccentric training. The main limitations in applying these conclusions to humans are the differences in phenotypic expression between humans and genetically homologous animal models and in the significant biomechanical differences between humans and these animal models.

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Questions Translocation of topsoil and its seed bank for ecological restoration is increasingly popular. How representative is the soil seed bank of the extant vegetation at the source site? What influence does the transfer process have on germinant density, species and plant functional type composition? Does smoke and heat treatment of transferred topsoil enhance germination and potential for restoration success? Location Banksia woodland of the Swan Coastal Plain, Western Australia. Methods To assess the efficacy of topsoil transfer for return of native plant species, we measured topsoil seed bank characterisitcs in situ proir to vegetation clearing, and immediately after transfer of the topsoil to an adjacent, degraded mediterranean‐type woodland in southwest Australia. Glasshouse germination of topsoil samples from 24 pre‐ and 24 post‐transfer plots was used to quantify the effects of transfer and soil depth on germinant density, species richness, plant functional types and seed bank similarity to in situ vegetation. Application of germination cues (heat + smoke) was used to explore the impact of topsoil transfer on seed germination and emergence. Results Topsoil transfer significantly reduced germinant densities (pre‐transfer 1692–4239 germinants·m−2, post‐transfer 795–1016 germinants·m−2; t = 6.7, P < 0.001) and shifted community structure (MRPP: A = 0.13, P < 0.001), including a reduction of woody species density by 81%. For the majority of functional types, heat and smoke failed to stimulate additional germination post‐transfer, suggesting soil transfer simulated the effect of fire‐related germination cues. Conclusion Although topsoil transfer translocated many viable native seeds, potential restoration success was hindered by reduced germinant densities. This was mostly attributable to a dilution effect associated with mixing of transferred topsoil, so that many seeds were buried too deep to emerge. However, total reductions were greater than expected based on dilution alone, suggesting some seed mortality during the transfer process. Transfer shifted composition towards dominance by annual species, suggesting the need for topsoil transfer to be supplemented by other restoration techniques.

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Consumer and rehabilitation provider factors that might limit employment opportunities for 154 individuals with six slowly progressive neuromuscular diseases (NMD) were investigated. The NMDs were spinal muscular atrophy (SMA), hereditary motor sensory neuropathy (HMSN), Becker's muscular dystrophy (BMD), facioscapulohumeral muscular dystrophy (FSHD), myotonic muscular dystrophy (MMD), and limb-girdle syndrome (LGS). Forty percent were employed in the competitive labor market at the time of the study, 50% had been employed in the past, and 10% had never been employed. The major consumer barrier to employment was education. Other important factors were type of occupation, intellectual capacity, psychosocial adjustment, and the belief by most individuals that their physical disability was the only or major barrier to obtaining a job. Psychological characteristics were associated with level of unemployment. However, physical impairment and disability were not associated with level of unemployment. There also were differences among the types of NMDs. Compared with the SMA, HMSN, BMD, and FSHD groups, the MMD and LGS groups had significantly higher levels of unemployment, lower educational levels, and fewer employed professional, management, and technical workers. Nonphysical impairment factors such as a low percentage of college graduates, impaired intellectual function in some individuals, and poor psychological adjustment were correlated with higher unemployment levels in the MMD group. Unemployment in the LGS group was correlated with a failure to complete high school. Major provider barriers to employment were the low level of referrals to Department of Rehabilitation by physicians and the low percentage of acceptance into the State Department of Rehabilitation. The low rate of acceptance was primarily attributable to the low number of referrals compounded by a lack of counselor experience with individuals with NMD. Both consumer and provider barriers may contribute to the lack of interest in obtaining a job.