Breaking the operator variability in Kibler's scapular dyskinesis assessment.

INTRODUCTION: Alterations of scapular kinematics are generically reported as scapular dyskinesis (SD), and are a nonspecific response to various shoulder pathologies. The most widely used classification is Kibler's (K), which is, however, characterized by poor sensitivity. To overcome this limit, using a 3D motion analysis system, we identified a specific pattern for each type of SD according to Kibler. MATERIALS AND METHODS: We analyzed 34 patients with a total of 68 shoulders who came to our observation for shoulder pain. All patients underwent clinical examination, video-recording and motion analysis with SHoW Motion 3D kinematic tracking system (SM). Three independent observers classified SD into K types I, II and III. Only patients with concordant classification among the 3 operators were studied to identify a characteristic graphic pattern by type of SD. RESULTS: Typical patterns emerged from the examination with SM. K. type 1 consists of decreased or reversed posterior tilt and increased protraction in flexion-extension (FE) in early degrees of motion. K. type 2 consists of increased protraction and marked reversal of lateral rotation in abduction-adduction (Ab-Ad) in early degrees of movement. K. type 3 has been subdivided into two subgroups: K. type 3-A, composed of patients with massive rotator cuff lesions, shows an increase in all scapular movements in both FE and Ab-Ad. K. type 3-B, composed of patients with scapular stiffness and/or impingement, presents a slight increase in posterior tilt and lateral rotation in the final grades of FE and Ab-Ad. CONCLUSIONS: The SM system allows reproducible dynamic analyses with low intra- and intra- operator variability. In our study, we demonstrated its applicability in the classification of SD. It also provides an objective and quantitative assessment of motor pattern alteration that is essential in the follow-up of patients to evaluate the effectiveness of rehabilitation and/or surgical treatment. LEVEL OF EVIDENCE 3: According to "The Oxford 2011 Levels of Evidence".

Principal component analysis of large layer density in Compton scattering measurements

A multivariate approach based on Principal Component Analysis (PCA) was used to analyze the energy distribution of n Monte Carlo simulated Compton scattered photon spectra describing the electron density of large layers. Three to five layers with different density distribution were used to test the algorithm; each layer was obtained by collecting 25 Compton spectra coming from sensitive volumes (SVs) where the complementary conditions of high and low density were realized (respectively full and void SV). The density variation inside a single layer is described by a two principal components (PCs) linear model that depicts the electron density of each SV: the layer density distribution appears to be correctly described even in the presence of very low signal-to-noise Compton spectra. Density profiles for layers at different depths were comparatively analyzed in order to show that, at least within one mean-free-path distance, it is possible to describe the layer density distribution by the PCA without any correction for the beam attenuation.

Prognostic scores for use in African meningococcal epidemics.

Current WHO guidelines for the case management of meningococcal infections during epidemics in developing countries often cannot be applied, largely because of the limited health resources in such countries. Several scoring scales based on clinical and laboratory features in numerous combinations have been developed for the management of meningococcal infections in developed countries, and these have facilitated early identification of patients with fulminant disease and thus early intervention and reduction in mortality. Unfortunately such scoring scales are not appropriate for use in developing countries. We identified hypotension, tachycardia, tachypnoea, delay in capillary refill time, coma, absence of neck stiffness and petechiae and/or purpura as simple prognostic factors of meningococcal disease. Two scores were developed: score I, which includes all seven prognostic factors, had a sensitivity and specificity of 80% and 94%, respectively. Score II, which excluded hypotension, had a sensitivity and specificity of 73.3% and 89.7%, respectively. Quick and simple scoring scales are therefore not only applicable but useful for the case management of patients in meningococcal epidemics in developing countries.

Instances of sex inversion in the domesticated swordtail, Xiphophorus helleri Heckel (Pisces, Osteichthyes).

3 protogynous hermaphrodites were found in a domesticated strain of Xiphophorus helleri, confirming much doubted observations by older authors. It therefore seems that sex determination may vary between strains, certain strains being strictly gonochoristic but others being capable of true hermaphroditism.