The effects of dorso-lumbar motion restriction on energy use and center of mass movement during running.

The effects of restricting dorso-lumbar spine mobility on oxygen consumption in runners was investigated, as was vertical movement of the body's center of mass. Thermoplastic casting material was fashioned into a rigid orthosis and used to restrict spinal motion during running. Volunteers ran on a treadmill at 2.78 m/sec, under normal conditions and with spinal motion restricted. Oxygen consumption was assessed via a Douglas bag set-up. Separately, vertical movement of the center of mass was assessed with a Panasonic recorder. RESULTS: Casted running resulted in an increase in oxygen consumption (p < 0.01). Casted running resulted in less vertical movement of the body's center of mass (p < 0.01). CONCLUSIONS: Spinal mobility has statistically significant effects on the energy used during running and on the vertical movement of the center of mass. A running style that causes the body to use more energy is inefficient and can lead to earlier onset of fatigue. It can make the runner more prone to overuse injuries. We hypothesize that less movement of the center of mass vertically can affect stride length, lead to more strides being used to cover a specific distance and thus could contribute to earlier onset of fatigue and overuse injury. More research needs to be done on this topic.

The crural interosseous membrane re-visited: a histological and microscopic study.

The aim of this study was to characterize the microscopic structure and sensory nerve endings of the crural interosseous membrane (IM). 13 IMs from 7 cadavers were used to analyze the organization of the collagen fibers, IM's thickness, distribution of elastic fibers and nerve elements. The IM is mainly a two-layer collagen fascicle structure with the collagen fibers of adjacent layers orientated along different directions, forming angles of 30.5 +/- 1.7° at proximal and 26.6 +/- 2.1° at distal part (P>0.05). The percentage of elastic fibers between the two layers and inside the collagen fascicle layer is 10.1 +/- 0.5% and 2.2 +/- 0.1% (P<0.001). The IM's thickness at proximal, middle, and distal parts is 268.5 +/- 18.6µm; 293.2 +/- 12.5µm; 365.3 +/- 19.3 µm, respectively (Proximal vs Distal: P<0.001; Middle vs Distal: P<0.05). Nerve elements were present and located both inside and on the surface of the IM, whereas the mechanoreceptors are mainly located on the surface of the IM. Free nerve endings (33.3 +/- 5.0/cm2) and Ruffini corpuscles (3.4 +/- 0.6/cm2) were the predominant sensory elements, while Pacinian corpuscles (1.3 +/- 0.7/cm2) were rarely found. The type of mechanoreceptors found suggests that the IM may play a role in proprioception.

Effect of whole body vibration on cervical (neck) proprioception in young, healthy individuals serving as their own control: a pilot study.

OBJECTIVE: The objective of this pilot study is to determine the effects of whole body vibration on head repositioning accuracy. METHODS: Twenty-one participants had a bicycle helmet with an attached laser pointer placed on their heads while standing on a vibration platform. After aligning the laser beam to their determined neutral position on wall-mounted chart paper, they were instructed to close their eyes, flex their neck maximally then return to their perceived neutral position. The point where the laser beam stopped as close to the neutral position as possible was marked on the chart and the sequence was repeated for extension, left and right rotation and left and right lateral flexion. The vibration platform was then activated and the process was repeated for the same six neck movements. RESULTS: T-tests showed significant differences (p < 0.01) for head repositioning errors between normal and vibration data for all neck movements (in mm), except flexion, with vibration trials exhibiting greater re-positioning errors. Data tabulated from the four Cartesian quadrants demonstrated a preponderance of overshoot re-positioning errors in which the laser stopped in individual Cartesian quadrants for each movement and each subject. CONCLUSIONS: Whole body vibration contributes to greater head repositioning errors in young, healthy, asymptomatic individuals. Larger scale trials should establish a normal data base for head re-positioning with vibration. Future studies might investigate the relationship between whole body vibration on neck proprioception as an indicator of therapeutic efficacy in neck disorders.

OBJECTIF: La présente étude pilote vise à examiner les effets de la vibration transmise à l'ensemble du corps sur la précision du repositionnement de la tête. MÉTHODOLOGIE: On a demandé à vingt et un participants de se tenir en station debout sur une plateforme vibrante en portant un casque de cycliste équipé d'un pointeur au laser. Après avoir aligné le faisceau laser avec leur position neutre sur un tableau à feuilles mural, on a demandé aux participants de fermer les yeux, de fléchir le cou au maximum et de revenir à la position qu'ils percevaient comme neutre. Le point auquel le faisceau laser s'est arrêté le plus près possible de la position neutre a été marquée sur le tableau; on a recommencé la séquence pour l'extension, la rotation vers la gauche et vers la droite et la flexion latérale vers la gauche et vers la droite. On a mis en service la plateforme vibrante et repris la séquence pour les six mêmes mouvements du cou. RÉSULTATS: Les tests T ont révélé d'importants écarts (p < 0,01) pour ce qui est des erreurs de repositionnement entre les données normales et les données sur la vibration pour tous les mouvements du cou (en mm), sauf la flexion, les essais avec vibration étant ceux pour lesquels les erreurs de repositionnement étaient les plus graves. Les données totalisées à partir des quatre quadrants cartésiens révélaient une prépondérance d'erreurs de repositionnement lorsque le faisceau laser s'arrêtait dans les quadrants cartésiens individuels pour chaque mouvement et chaque sujet. CONCLUSIONS: La vibration transmise à l'ensemble du corps contribue à une hausse du nombre d'erreurs de repositionnement de la tête chez des sujets jeunes, en bonne santé et asymptomatiques. On devrait faire des essais à plus grande échelle pour créer une base de données sur le repositionnement de la tête après l'exposition à des vibrations. On pourrait faire d'autres études sur le lien existant entre la vibration transmise à l'ensemble du corps et la proprioception cervicale servant d'indicateur de l'efficacité des traitements dans les troubles de la colonne cervicale.

The effects of dorso-lumbar motion restriction on EMG activity of selected muscles during running.

The effects of restricting dorso-lumbar spine mobility on electromyographic activity of the erector spinae, quadriceps femoris, hamstrings and gastrocnemius muscles in runners was investigated. Thermoplastic casting material was fashioned into a rigid orthosis and used to restrict spinal motion during running. Volunteers ran on a treadmill at 2.78 m/sec, under normal conditions and with spinal motion restricted. Surface electromyographic data was collected during both sets of trials. Normal electromyographic data was also compared with previous authors to determine similarity with their electromyographic data. RESULTS: Casted running resulted in an increase in erector spinae (p < 0.01) and quadriceps femoris (p = 0.02) electromyography activity. Total stride time and swing time of gait were decreased during casted running (p < 0.01), indicating a shift towards shorter and thus more frequent steps to run the same distance. The normal electromyographic data collected was in agreement with previously reported work. CONCLUSIONS: Neurological control over muscle and the fascia surrounding it is responsible for joint movement and load transfer. Experimentally restricting spinal motion during running demonstrated an increase in erector spinae and rectus femoris electromyographic activity. This lends support to the hypothesis that decreased spinal mobility may be a contributing factor to overuse muscle injuries in runners.

The effects of dorso-lumbar motion restriction on the ground reaction force components during running.

PURPOSE: The effects of restricting dorso-lumbar spine mobility on ground reaction forces in runners was measured and assessed. METHODS: A semi-rigid cast was used to restrict spinal motion during running. Subjects ran across a force platform at 3.6 m/s, planting the right foot on the platform. Data was collected from ten running trials with the cast and ten without the cast and analysed. RESULTS: Casted running showed that the initial vertical heel strike maximum was increased (p < .02) and that the anterior-posterior deceleration impulse was increased (p < .01). The maximum vertical ground reaction force was decreased in casted running (p < .01), as was the anterior-posterior acceleration impulse (p < .02). There was a trend for increased medial-lateral impulse in the uncasted state, but this was not statistically significant. CONCLUSIONS: Spinal mobility and fascia contribute to load transfer between joints and body segments. Experimentally restricting spinal motion during running results in measurable and repeatable alterations in ground reaction force components. Alterations in load transfer due to decreased spinal motion may be a factor contributing to selected injuries in runners.

Aspergillus fumigatus during stable state and exacerbations of COPD.

Bacteria are often isolated in stable chronic obstructive pulmonary disease (COPD). Whether fungi are also commonly present and associated with clinical and pathological features of disease is uncertain. We investigated the frequency of filamentous fungal culture and IgE sensitisation to Aspergillus fumigatus and the relationship to clinical outcomes in COPD subjects. COPD subjects were recruited to enter a 1-year observational study. Assessments of lung function, allergen testing and sputum analysis for inflammation, bacteria and fungus were undertaken in COPD subjects and healthy smoking and nonsmoking controls. Filamentous fungi were cultured at baseline in 49% (63 out of 128) of COPD subjects, of which 75% (47 out of 63) were A. fumigatus. Fungus was cultured in three out of 22 controls (two were A. fumigatus). The total sputum cell count and inhaled corticosteroid dosage were significantly increased in COPD patients with a positive filamentous fungal culture at baseline (p<0.05). Sensitisation to A. fumigatus was present in 13% of COPD subjects and was associated with worse lung function (forced expiratory volume in 1 s 39% predicted versus 51% predicted; p=0.01), but not related to filamentous fungal culture. A. fumigatus sensitisation is related to poor lung function. Positive filamentous fungal culture is a common feature of COPD. The clinical significance of this remains uncertain.

Effectiveness of voriconazole in the treatment of Aspergillus fumigatus-associated asthma (EVITA3 study).

BACKGROUND: IgE sensitization to Aspergillus fumigatus and a positive sputum fungal culture result are common in patients with refractory asthma. It is not clear whether these patients would benefit from antifungal treatment. OBJECTIVES: We sought to determine whether a 3-month course of voriconazole improved asthma-related outcomes in patients with asthma who are IgE sensitized to A fumigatus. METHODS: Asthmatic patients who were IgE sensitized to A fumigatus with a history of at least 2 severe exacerbations in the previous 12 months were treated for 3 months with 200 mg of voriconazole twice daily, followed by observation for 9 months, in a double-blind, placebo-controlled, randomized design. Primary outcomes were improvement in quality of life at the end of the treatment period and a reduction in the number of severe exacerbations over the 12 months of the study. RESULTS: Sixty-five patients were randomized. Fifty-nine patients started treatment (32 receiving voriconazole and 27 receiving placebo) and were included in an intention-to-treat analysis. Fifty-six patients took the full 3 months of medication. Between the voriconazole and placebo groups, there were no significant differences in the number of severe exacerbations (1.16 vs 1.41 per patient per year, respectively; mean difference, 0.25; 95% CI, 0.19-0.31), quality of life (change in Asthma Quality of Life Questionnaire score, 0.68 vs 0.88; mean difference between groups, 0.2; 95% CI, -0.05 to -0.11), or any of our secondary outcome measures. CONCLUSION: We were unable to show a beneficial effect of 3 months of treatment with voriconazole in patients with moderate-to-severe asthma who were IgE sensitized to A fumigatus on either the rate of severe exacerbations, quality of life, or other markers of asthma control.

Routine processing procedures for isolating filamentous fungi from respiratory sputum samples may underestimate fungal prevalence.

Colonization of the airways by filamentous fungi can occur in asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis. A recent study found IgE sensitization to Aspergillus fumigatus to be associated with reduced lung function. Significantly higher rates of A. fumigatus were detected in sputum from asthmatics sensitized to this fungus compared to non-sensitized asthmatics. The rate of positive cultures was far higher than equivalent historical samples analysed by the local clinical laboratory following protocols recommended by the UK Health Protection Agency (HPA). This study compares the HPA procedure with our sputum processing method, whereby sputum plugs are separated from saliva and aliquots of approximately 150 mg are inoculated directly onto potato dextrose agar. A total of 55 sputum samples from 41 patients with COPD were analyzed, comparing fungal recovery of five dilutions of sputa on two media. Isolation of A. fumigatus in culture was significantly higher using the research approach compared to the HPA standard method for mycological investigations (P < 0.001). There was also a significant difference in the recovery rate of A. fumigatus (P < 0.05) between media. This highlights the need for a standardized approach to fungal detection which is more sensitive than the method recommended by the HPA.