الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Successful shoulder arthroscopy depends upon a systemic approach and thorough knowledge of the anatomy of the gleno-humeral joint. Variations in the normal anatomy are not uncommon. To achieve a thorough and reproducible arthroscopic examination, structures should be identified and examined systematically.Only 25 to 30% of the humeral head is covered by the glenoid surface in any anatomic position and this reflects the inherent instability of the joint. The glenoid labrum increases the area and depth of the glenoid cavity. The stability ratio decreased approximately 20% after removal of the labrum. Because the anterior glenoid labrum serves as the anchor point for the anterior ligamentous complex, it is often the site of failure in shoulder dislocation. The major static stabilizer of the shoulder joint consists of the capsuloligamentous complex, with the IGHL being the most essential component of the complex. Glenohumeral instability is the inability to maintain the humeral head centered in the glenoid fossa. Numerous classifications for shoulder instability have been described and are obtained from a detailed history, physical examination, and radiographic studies The Bankart lesion that was originally described as the ”essential lesion” to shoulder instability does not appear to be solely responsible for anterior glenohumeral translation, some degree of associated capsular laxity must be present. Patients younger than 20 years at the time of the initial dislocation, have up to a 90% chance of having recurrent instability. A careful clinical evaluation along with a review of the radiographs and sometimes of a specialized magnetic resonance imaging scan with gadolinium and abduction with external rotation positioning usually confirms the diagnosis of anterior shoulder instability.