Body segment parameters of Paralympic athletes from dual-energy X-ray absorptiometry

The final publication is available at Springer via http://dx.doi.org/10.1007/s12283-016-0200-3This research represents the first documented investigation into the body segment parameters of Paralympic athletes (e.g., individuals with spinal cord injuries and lower extremity amputations). Two-dimensional body segment parameters (i.e., mass, length, position vector of the center of mass, and principal mass moment of inertia about the center of mass) were quantified from dual-energy X-ray absorptiometry (DXA). In addition to establishing a body segment parameter database of Paralympic athletes for prospective biomechanists and engineers, the mass of each body segment as experimentally measured via the DXA imaging was compared with that reported by previous research of able-bodied cadavers. In general, there were significant differences in the body segment masses between the different methods. These findings support the implementation of the proposed database for developing valid multibody biomechanical models of Paralympic athletes with distinct physical disabilities.This research was funded by Dr. John McPhee’s Tier I Canada Research Chair in Biomechatronic System Dynamics

GUILLÉN HERNÁNDEZ [Material gráfico]

NIÑOS DE Y ABUELACopia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 201

The effect of growth on the correlation between the spinal and rib cage deformity: implications on idiopathic scoliosis pathogenesis

<p>Abstract</p> <p>Background</p> <p>Numerous studies have attempted to quantify the correlation between the surface deformity and the Cobb angle without considering growth as an important factor that may influence this correlation. In our series, we noticed that in some younger referred children from the school-screening program there is a discrepancy between the thoracic scoliometer readings and the morphology of their spine. Namely there is a rib hump but no spinal curve and consequently no Cobb angle reading in radiographs, discrepancy which fades away in older children. Based on this observation, we hypothesized that in scoliotics the correlation between the rib cage deformity and this of the spine is weak in younger children and vice versa.</p> <p>Methods</p> <p>Eighty three girls referred on the basis of their hump reading on the scoliometer, with a mean age of 13.4 years old (range 7–18), were included in the study. The spinal deformity was assessed by measuring the thoracic Cobb angle from the postero-anterior spinal radiographs. The rib cage deformity was quantified by measuring the rib-index at the apex of the thoracic curve from the lateral spinal radiographs. The rib-index is defined as the ratio between the distance of the posterior margin of the vertebral body and the most extended point of the most projecting rib contour, divided by the distance between the posterior margin of the same vertebral body and the most protruding point of the least projecting rib contour. Statistical analysis included linear regression models with and without the effect of the variable age. We divided our sample in two subgroups, namely the younger (7–13 years old) and the older (14–18 years old) than the mean age participants. A univariate linear regression analysis was performed for each age group in order to assess the effect of age on Cobb angle and rib index correlation.</p> <p>Results</p> <p>Twenty five per cent of patients with an ATI more than or equal 7 degrees had a spinal curve under 10 degrees or had a straight spine. Linear regressions between the dependent variable "Thoracic Cobb angle" with the independent variable "rib-index" without the effect of the variable "age" is not statistical significant. After sample split, the linear relationship is statistically significant in the age group 14–18 years old (p < 0.03).</p> <p>Conclusion</p> <p>Growth has a significant effect in the correlation between the thoracic and the spinal deformity in girls with idiopathic scoliosis. Therefore it should be taken into consideration when trying to assess the spinal deformity from surface measurements. The findings of the present study implicate the role of the thorax, as it shows that the rib cage deformity precedes the spinal deformity in the pathogenesis of idiopathic scoliosis.</p

Massive rotator cuff tears: functional outcome after debridement or arthroscopic partial repair

Background The surgical treatment of massive rotator cuff tears (RCT) is still controversial and can be based on a variety of different surgical repair methods. This study investigated the effectiveness of arthroscopic debridement or arthroscopic partial repair in patients with massive RCT. Materials and methods This prospective, randomized study involved forty-two patients with massive RCT (fatty infiltration stage 3 or 4) treated with either arthroscopic partial repair or arthroscopic debridement were selected to detect possible differences in functional outcome. Both groups were matched according to age and gender. Patients were examined before, and 16 ± 3 and 24 ± 2 months after surgery. The status of the rotator cuff repair was determined using ultrasonographic evaluation. Results Regardless of the treatment group, postoperative results demonstrated highly significant improvements compared with preoperative values in most parameters. The overall Constant score in the partial repair group was superior to the outcome in the debridement group (P \ 0.01, F = 8.561), according to better results in abductio

The conventional gait model - success and limitations

The Conventional Gait Model (CGM) is a generic name for a family of closely related and very widely used biomechanical models for gait analysis. After describing its history, the core attributes of the model are described followed by evaluation of its strengths and weaknesses. An analysis of the current and future requirements for practical biomechanical models for clinical and other gait analysis purposes which have been rigorously calibrated suggests that the CGM is better suited for this purpose than any other currently available model. Modifications are required, however, and a number are proposed

Diagnosis and management of adhesive capsulitis

Adhesive capsulitis is a musculoskeletal condition that has a disabling capability. This review discusses the diagnosis and both operative and nonoperative management of this shoulder condition that causes significant morbidity. Issues related to medications, rehabilitation, and post surgical considerations are discussed

Managing peatland vegetation for drinking water treatment

Peatland ecosystem services include drinking water provision, flood mitigation, habitat provision and carbon sequestration. Dissolved organic carbon (DOC) removal is a key treatment process for the supply of potable water downstream from peat-dominated catchments. A transition from peat-forming Sphagnum moss to vascular plants has been observed in peatlands degraded by (a) land management, (b) atmospheric deposition and (c) climate change. Here within we show that the presence of vascular plants with higher annual above-ground biomass production leads to a seasonal addition of labile plant material into the peatland ecosystem as litter recalcitrance is lower. The net effect will be a smaller litter carbon pool due to higher rates of decomposition, and a greater seasonal pattern of DOC flux. Conventional water treatment involving coagulation-flocculation-sedimentation may be impeded by vascular plant-derived DOC. It has been shown that vascular plant-derived DOC is more difficult to remove via these methods than DOC derived from Sphagnum, whilst also being less susceptible to microbial mineralisation before reaching the treatment works. These results provide evidence that practices aimed at re-establishing Sphagnum moss on degraded peatlands could reduce costs and improve efficacy at water treatment works, offering an alternative to ‘end-of-pipe’ solutions through management of ecosystem service provision

Pollen and Phytoliths from Fired Ancient Potsherds as Potential Indicators for Deciphering Past Vegetation and Climate in Turpan, Xinjiang, NW China

It is demonstrated that palynomorphs can occur in fired ancient potsherds when the firing temperature was under 350°C. Pollen and phytoliths recovered from incompletely fired and fully fired potsherds (ca. 2700 yrs BP) from the Yanghai Tombs, Turpan, Xinjiang, NW China can be used as potential indicators for reconstructing past vegetation and corresponding climate in the area. The results show a higher rate of recovery of pollen and phytoliths from incompletely fired potsherds than from fully fired ones. Charred phytoliths recovered from both fully fired and incompletely fired potsherds prove that degree and condition of firing result in a permanent change in phytolith color. The palynological data, together with previous data of macrobotanical remains from the Yanghai Tombs, suggest that temperate vegetation and arid climatic conditions dominated in the area ca. 2700 yrs BP

Patterns of Hybrid Loss of Imprinting Reveal Tissue- and Cluster-Specific Regulation

Background: Crosses between natural populations of two species of deer mice, Peromyscus maniculatus (BW), and P. polionotus (PO), produce parent-of-origin effects on growth and development. BW females mated to PO males (bw6po) produce growth-retarded but otherwise healthy offspring. In contrast, PO females mated to BW males (PO6BW) produce overgrown and severely defective offspring. The hybrid phenotypes are pronounced in the placenta and include PO6BW conceptuses which lack embryonic structures. Evidence to date links variation in control of genomic imprinting with the hybrid defects, particularly in the PO6BW offspring. Establishment of genomic imprinting is typically mediated by gametic DNA methylation at sites known as gDMRs. However, imprinted gene clusters vary in their regulation by gDMR sequences. Methodology/Principal Findings: Here we further assess imprinted gene expression and DNA methylation at different cluster types in order to discern patterns. These data reveal PO6BW misexpression at the Kcnq1ot1 and Peg3 clusters, both of which lose ICR methylation in placental tissues. In contrast, some embryonic transcripts (Peg10, Kcnq1ot1) reactivated the silenced allele with little or no loss of DNA methylation. Hybrid brains also display different patterns of imprinting perturbations. Several cluster pairs thought to use analogous regulatory mechanisms are differentially affected in the hybrids. Conclusions/Significance: These data reinforce the hypothesis that placental and somatic gene regulation differs significantly, as does that between imprinted gene clusters and between species. That such epigenetic regulatory variatio