Symptoms And Treatment of Anterior Instability:

Shoulder Instability may be anterior, posterior, inferior or multidirectional.

Anterior Instability

Anterior glenohumeral instability may be post-traumatic, as a result of an acute episode of trauma causing anterior dislocation or subluxation, or a traumatic, or a combination-for instance, an acute traumatic episode in a lax shoulder.

In differentiating between the two types of anterior instability, the history is the most useful factor. In post-traumatic instability, the patient usually reports a specific incident that precipitated the problem. This is commonly a moderately forceful abduction and external rotation injury. Following this episode, however, the patient reports that the shoulder has never returned to normal. In many post-traumatic types of instability a true dislocation may not have occurred and the symptoms are related to recurrent subluxation. The atraumatic type of abnormality is common in people with capsular laxity including sportspeople, especially those involved in repeated overhead activities such as baseball pitchers, javelin throwers, swimmers and tennis players.

Symptoms of Anterior Instability

The symptoms of anterior instability include recurrent dislocation or subluxation, shoulder pain and episodes of dead arm syndrome.

• Pain usually arises from impingement of the rotator cuff tendons with recurrent anterior translation of the humeral head and recurrent silent subluxation.
• This is aggravated by the eventual weakening of the rotator cuff muscles which, in turn, fail to depress the humeral head adequately.
• The recurrent episodes of impingement result in a rotator cuff tendinopathy.
• Anterior shoulder pain in association with post-traumatic anterior instability may be due to catching of a labral detachment.
• This pain and sensation of catching may be reproduced on anterior drawer or load and shift testing.
• The dead arm effect is thought to arise from traction or impingement on the neurovascular structures, causing transient numbness and weakness of the arm.
• This usually resolves after a few minutes. The episodes of subluxation and dislocation usually increase in frequency.

Occasionally, a stage is reached where relatively minor activities such as yawning or rolling over in bed may result in a subluxation or dislocation.

Treatment

As outlined earlier, a traditional sling should not be used to manage instability.

• If aggressive non-operative treatment is to be pursued, then the arm should be placed in external rotation of 30 degree for three weeks night and day to reduce the Bankart lesion.
• There are a large number of different procedures used to treat shoulder instability. In athletes, particularly those whose dominant throwing arm is involved, the underlying mechanical lesion should be corrected.
• In most cases, this involves repair of the Bankart lesion, which may be performed either as an open or arthroscopic procedure.
• Other mechanical problems such as a tear in the rotator cuff may also be corrected.
• If an extremely large Hill’-Sachs lesion is present, then a procedure such as bone grafting may be necessary.
• In treating atraumatic instability, intensive rehabilitation involves strengthening of the dynamic stabilizers (rotator cuff muscles) and scapular stabilizing muscles, with particular emphasis on the muscles opposing the direction of the instability.
• Modification of sporting activity may also be helpful. If conservative measures fail, then surgery should be considered .This usually involves a capsular shift procedure.