Computed Tomography Measurement of Rib Cage Morphometry in Emphysema

Background: Factors determining the shape of the human rib cage are not completely understood. We aimed to quantify the contribution of anthropometric and COPD-related changes to rib cage variability in adult cigarette smokers. Methods: Rib cage diameters and areas (calculated from the inner surface of the rib cage) in 816 smokers with or without COPD, were evaluated at three anatomical levels using computed tomography (CT). CTs were analyzed with software, which allows quantification of total emphysema (emphysema%). The relationship between rib cage measurements and anthropometric factors, lung function indices, and %emphysema were tested using linear regression models. Results: A model that included gender, age, BMI, emphysema%, forced expiratory volume in one second (FEV1)%, and forced vital capacity (FVC)% fit best with the rib cage measurements (R2  = 64% for the rib cage area variation at the lower anatomical level). Gender had the biggest impact on rib cage diameter and area (105.3 cm2; 95% CI: 111.7 to 98.8 for male lower area). Emphysema% was responsible for an increase in size of upper and middle CT areas (up to 5.4 cm2; 95% CI: 3.0 to 7.8 for an emphysema increase of 5%). Lower rib cage areas decreased as FVC% decreased (5.1 cm2; 95% CI: 2.5 to 7.6 for 10 percentage points of FVC variation). Conclusions: This study demonstrates that simple CT measurements can predict rib cage morphometric variability and also highlight relationships between rib cage morphometry and emphysema

Posterior shoulder instability: current concepts review

Purpose: Posterior shoulder instability has been difficult to diagnose and even more challenging to manage. However, it is being diagnosed and treated more frequently, particularly after sports injuries. The purpose of this article is to review literature concerning the management of these pathologies. Methods: A literature review was carried out in the main medical databases to evaluate the several studies concerning the open and arthroscopic treatment of posterior shoulder instability. Results: Because of better awareness of the pathology, better technical investigations, and a better understanding of shoulder biomechanics, more and more mechanical factors that can cause posterior instability have been described. Structural abnormalities can be divided into bony abnormalities and soft-tissue abnormalities. Each group can also be divided into abnormalities caused by trauma (macro- or microtrauma) or congenital. These abnormalities can be treated with non-anatomic and anatomic stability procedures. During the last decades, the latter have been described more frequently, most of them arthroscopically. Conclusion: For surgical treatment to be successful, the instability must be attributable to mechanical factors that can be modified by surgery. Because of better knowledge of the pathology, a more specific surgery can be performed. This lesion-specific surgery has improved clinical results compared to non-anatomic stability procedures, particularly when that surgery has been performed arthroscopically