The shoulder complex is built for mobility, however this ability to move comes with the designation of being the most unstable joint in the body. The shoulder is composed of three osseous joints and one articulation, with stability provided by muscles, ligaments, the glenoid labrum and joint capsule.
The shoulder has three osseous, or bone-to-bone, joints.
- The glenohumeral joint (shoulder joint)
- The acromioclavicular joint
- The sternoclavicular joint
The shoulder also contains the scapulothoracic thoracic articulation, which provides stability between the scapula (shoulder blade) and ribs of the posterior aspect of the thoracic (chest) cage.
Shoulder Conditions
Common conditions of the shoulder joints include:
- Shoulder osteoarthritis
- Humeral fractures
- Shoulder dislocation
- Shoulder subluxation
- Shoulder impingement
- Acromioclavicular arthritis
Common conditions of the muscles surrounding the shoulder include:
- Rotator cuff tendinitis
- Bicep tendinitis
- Shoulder impingement
- Calcific tendonitis
- Rotator cuff tear