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A Patient’s Guide to Sternoclavicular Joint Problems

Introduction

The sternoclavicular (SC) joint is important because it helps support the shoulder. The SC joint links the bones of the arms and shoulder to the vertical skeleton.

Most SC joint problems are relatively minor. However, certain types of injuries require immediate medical attention.

This document will help you understand

what the SC joint is […]

Humeral Bone Deficiency

Humeral head defects are commonly present in patients with shoulder instability. The defects are usually small and carry the eponym Hill-Sachs lesion when secondary to anterior instability and reverse Hill-Sachs lesions when secondary to posterior instability.

Although quite ubiquitous in recurrent anterior shoulder instability, the management of large Hill-Sachs defects remains controversial especially in […]

Dynamic Stability Factors

Glenohumeral stability is mainly achieved through dynamic factors. Active contraction of the rotator cuff contributes to joint stabilization by coordinated muscular activity and by secondary tightening of the ligamentous constraints. This effect works in combination with the concavity-compression mechanism, in which muscle contraction causes compression of nearly congruent articular surfaces into one another.

The rotator […]

Biomechanics of Shoulder Stability-Static Stability Factor

The glenohumeral joint is inherently unstable, with the large humeral head articulating with the small and shallow glenoid. Static stability is provided by the orientation of the articular surfaces, the articular conformity of humerus and the glenoid, the glenoid labrum, the negative intra-articular pressure, the adhesion-cohesion of synovial joint fluid, and the glenohumeral joint capsule […]

Rotator Cuff Muscles

The RTC is composed of the supraspinatus, the infraspinatus, the subscapularis, and the teres minor muscles. The tendinous portion of the supraspinatus interdigitates with the subscapularis and the infraspinatus to form a common, continuous insertion on the humeral head, enveloping approximately 75% of the GH articulation and with a mean area of insertion on the […]

Long Head of the Biceps

The long head of the biceps tendon has a variable origin, with 30% to 40% originating at the supraglenoid tubercle, 45% to 60% directly from the labrum, and 25% to 30% from both. It travels obliquely within the shoulder joint, then turns sharply to exit inferiorly beneath the transverse humeral ligament along the bicipital groove. […]

Scapula

The scapula is a flat, triangular-shaped bone that serves as the articulating surface for the head of the humerus as well as provides areas for 17 muscle attachments. With the arm at the side, the scapula overlaps the dorsal surfaces of the second to seventh ribs. It has three prominent projections: the spine, the coracoid […]

Resisted external rotation

Positioning.

The subject stands with the upper arm against the body and the elbow flexed to a right angle. The forearm is held in the sagittal plane, so keeping the shoulder in a neutral position.The examiner stands level with the subject’s arm. He places one hand on the opposite shoulder and the other hand against […]

Passive tests-Passive glenohumeral abduction

Positioning.

The subject stands with the upper arm alongside the body. The examiner stands level with and behind the subject’s arm. One hand takes hold of the elbow, just above the joint.The thumb of the other hand is placed against the lateral aspect of the lower angle of the scapula.

Procedure.

Abduct the arm […]

Palpation of the subscapularis tendon

The subscapularis muscle belly can only be reached by bringing the hand in between the scapula and the thorax. It cannot really be palpated. The tendinous insertion on the lesser tuberosity, however, can easily be palpated. The subject is in a half lying position on a couch, the upper arm along the body and the […]