**5.1 Patient history**

The examiner should obtain a thorough history, which should offer information regarding symptoms, type and direction of instability, age and time elapsed from the initial dislocation, number of instability episodes, need for medical assistance for reduction versus self-reduction, activity level and prior treatment.

The provocative position for dislocation is indicative of the direction of instability. Patients with anterior traumatic instability generally describe the event occurring with the arm in the abducted, extended and externally rotated position. Patients who do not recall a specific dislocation event may have pathologic instability due to generalized ligamentous laxity. Pain may also be associated with instability. For example, overhead-throwing athletes with anterior instability may complain of pain due to repetitive stress on the anteroinferior capsulolabral complex.

Patients who present with a long history of recurrent instability episodes, high-energy trauma leading to dislocation, a progressive ease of symptoms or demonstrate instability in the midrange of motion should be meticulously evaluated for glenohumeral bone deficiencies. The ability to voluntarily dislocate the shoulder should be thoroughly examined because it may be attributed to psychological factors and, secondly, is generally associated with increased rates of recurrence after surgery. Similarly, patients with multiple dislocation events or whose shoulders slip out with limited force (during sleep or when reaching overhead) may have a significant glenohumeral bone defect or other pathology, such as multidirectional laxity or glenoid hypoplasia. Therefore, they would necessitate a different surgical plan. Finally, the degree of disability and loss of functionality should be thoroughly evaluated as part of decision making.

#### **5.2 Physical examination**

Both shoulders are exposed for visual inspection and comparative examination. Testing for range of motion and overall muscle strength, and neurovascular examination are performed. The opposite shoulder and other joints are examined to assess the degree of ligamentous laxity normally present in any individual. Clinical tests for glenohumeral laxity and provocative or instability tests are the hallmarks in the physical examination of an unstable shoulder.

Examination for glenohumeral laxity includes the anterior and posterior drawer, and the anterior and posterior load and shift tests, which quantitate the amount of anterior and posterior humeral head translation respectively. The Gagey hyperabduction test is used to measure the laxity of the inferior glenohumeral ligament complex. The sulcus sign also evaluates glenohumeral laxity at the inferior direction when an inferior stress is applied with the arm in adduction and both neutral and 30o external rotation. It is important for the surgeon to discern between pathologic shoulder instability and normal laxity. Instability is generally described as symptomatic laxity, which requires the patients subjectively experiencing the shoulder subluxating or recalling a frank dislocation event. On the contrary, laxity is the normal translation between the components of the glenohumeral joint to achieve full normal range of motion (Bigliani et al, 1996).

Testing for instability includes the apprehension-relocation, and the anterior release and surprise tests. The apprehension test is positive when the patient experiences pain and has a subjective feeling of the arm dislocating when the shoulder is progressively moved to abduction and external rotation. It is especially important to determine the ease with which the shoulder begins to dislocate and engage on the glenoid. If this occurs even with limited external rotation it is highly likely that there exists an engaging hill-Sachs lesion or osseous glenoid defect. Similarly, patients with engaging Hill-Sachs lesions report episodes of instability in the midrange of shoulder abduction and external rotation.
