An Analysis of Capsular Area in Patients with Anterior, Posterior, and Multidirectional Shoulder Instability

Abstract

Our results reinforce the concept that capsular elongation and laxity, either preexisting or acquired, play a role in certain instability conditions of the shoulder. Additional work is needed to determine how to correlate surgical decision making with the cross-sectional area measurements demonstrated in this study.

Quantification and correlation of hip capsular volume to demographic and radiographic predictors

“…Because an injected dye distends the capsule, MRAs have been used as a tool to identify patulous capsules in shoulder instability [7,12,15,21,28]. To date, however, the utility of the MRA as a tool to detect patulous hip capsules is unclear.…”

Assessment of Capsular Insertion Type and of Capsular Elongation in Patients with Anterior Shoulder Instability and It's Correlation with Surgical Outcome: A Quantitative Assessment with Computed Tomography Arthrography

“…Throughout the imaging the patient was positioned into a in a neutral position with the upper extremity in anatomical position. 6) Basic axial computed tomography (CT) imaging was taken in 16-sections or in 64-sections of either 2 or 3 mm thickness with a multi-detector CT.…”

“…4,5) Shoulder instability has been shown to result by means of a large spectrum of pathological conditions such as labral deficiency, capsular elongation, patulousness of the shoulder capsule, ligament injury, bony defi-ciencies, and etc. [6][7][8] In 1962 Moseley 9) introduced a classification system based on the mode of capsular insertion for categorizing anatomical variations in the capsule that surrounds the glenohumeral joint. The three types of capsular insertion were as follows: type I, capsular insertion into the labral base; type II, capsular insertion into the glenoid fossa; and type III, capsular insertion into a more medial position following the scapular neck ( Fig.…”

Posterior Shoulder Instability in Athletes

“…Stretching of the capsule and the posterior band of the inferior glenohumeral ligament beyond their initial resting length in this position has been shown to be a potential cause of both posterior shoulder instability and multidirectional instability 21,22 . Biomechanical studies have also shown that the posterior capsule and the posterior band of the inferior glenohumeral ligament may be permanently deformed as a result of repetitive lowstrain cyclic loading (e.g., repetitive microtrauma) and that recurrent posteroinferior subluxation of the humeral head can lead to plastic deformation of the capsule [23][24][25] .…”