Recurrent posterior shoulder instability is an uncommon, debilitating condition in young adults that is being diagnosed with increasing frequency. Although a number of predisposing factors have been identified, their relative importance remains poorly understood. Poor results have been reported following operative intervention to treat recurrent posterior instability with nonanatomic techniques...

OBJECTIVE To review some of the important biomechanical factors that provide glenohumeral stability, along with the pathologic mechanisms involved in glenohumeral instability of the shoulder. DATA SOURCES Current English medical literature concerning the multiple pathologic factors involved in glenohumeral instability was reviewed. DATA SYNTHESIS Multiple dynamic and static factors control ...

BACKGROUND Shoulder activity level may be a risk factor for shoulder instability, an indication for surgical intervention, and a risk factor for failure of operative stabilization. HYPOTHESIS Patients undergoing shoulder stabilization surgery have a higher activity level compared with sex- and age-matched healthy controls. STUDY DESIGN Cross-sectional study. LEVEL OF EVIDENCE Level 2. M...

Laxity testing is an important part of the examination of any joint. In the shoulder, it presents unique challenges because of the complexity of the interactions of the glenohumeral and scapulothoracic joints. Many practitioners believe that laxity testing of the shoulder is difficult, and they are unclear about its role in evaluation of patients. The objectives of the various laxity and instab...

Both structural and non-structural components can contribute to shoulder instability. Classification and therefore management must recognise these factors to achieve functional stability. This paper discusses a classification system proposing three types of shoulder instability recognising the structural and non-structural components and that a continuum exists between pathologies. Structural c...

BACKGROUND The literature provides little information detailing the incidence of traumatic shoulder instability in young, healthy athletes. HYPOTHESIS Shoulder instability is common in young athletes. STUDY DESIGN Descriptive epidemiologic study. METHODS We prospectively captured all traumatic shoulder instability events at the United States Military Academy between September 1, 2004, and...

BACKGROUND Shoulder instability is a common problem in American football players entering the National Football League (NFL). Treatment options include nonoperative and surgical stabilization. PURPOSE This study evaluated how the method of treatment of pre-NFL shoulder instability affects the rate of recurrence and the time elapsed until recurrence in players on 1 NFL team. DESIGN Retrospec...

BACKGROUND The Western Ontario Shoulder Instability index (WOSI) is a patient-reported outcome measure for patients with shoulder instability. The purpose of this study was to validate the WOSI in a Dutch population by evaluating its structural validity, internal consistency, measurement error, reliability, and construct validity. Floor and ceiling effects were also addressed. METHODS Two coh...

Shoulder instability is a common problem which is defined as symptomatic motion of the glenohumeral joint, which can present as pain or sense of displacement [1]. There are several systems of classification in the literature of shoulder instability. Recently, to introduce some consensus, the FEDS system has been proposed [2]. The symptoms are classified according to Frequency (solitary, occasio...