In traumatic anterior Dislocation of shoulder there is complete separation of the articular surfaces of the glenohumeral joint caused by direct or indirect forces applied to the shoulder. Anterior dislocation most frequently occurs when there is a blow to the humerus while it is in a position of external rotation and abduction. Stability normally is provided by the subscapularis, glenohumeral ligament, and long head of the biceps when in that position. Poor integrity of any of these structures can predispose the joint to dislocation, or a significant blow to the arm may damage them along with the attachment of the anterior capsule and glenoid labrum (Bankart lesion). When dislocated, the humeral head usually rests in the subcoracoid region, rarely subclavicular or intrathoracic. Traumatic anterior dislocation is usually associated with a complete rupture of therotator cuff. Neurologic or vascular injuries may occur during dislocations. The axillary nerve is most commonly injured, but the brachial plexus or one of the peripheral nerves could be stretched or compressed.
Common Impairments
After an acute traumatic injury, symptoms from tissue damage include pain and muscle guarding from bleeding and inflammation. When a dislocation is associated with a complete rotator cuff tear, there is an inability to abduct the humerus against gravity, except the range provided by the scapulothoracic muscles. Asymmetric joint restrictions/hypermobilities. In an anterior instability, the posterior capsule may be tight; in a posterior instability, the anterior capsule may be tight. After healing, there may be adhesions.
With recurrent dislocations, the individual can dislocate the shoulder at will, or the shoulder may just dislocate when doing specific activities.
Common Functional Limitations/Disabilities
With rotator cuff rupture, inability to reach or lift objects to the level of horizontal, thus interfering with all activities using humeral elevation Possibility of recurrence when replicating the dislocating action With anterior dislocation, restricted ability in sports activities such as pitching, swimming, serving (tennis, volleyball), spiking (volleyball) Restricted ability, particularly when overhead or horizontal abduction movements are required in dressing, such as putting on a shirt or jacket, and with self-grooming, such as combing the back of the hair Discomfort or pain when sleeping on the involved side in some cases.
Management: Protection Phase After Closed Reduction of Anterior Dislocation
Reduction manipulations should be undertaken only by someone specially trained in the maneuver because of the vulnerability of the brachial plexus and axillary blood vessels.
Protect the Healing Tissue
After acute anterior dislocation in a young patient, the arm is immobilized for 3 to 4 weeks in a sling, which is removed only for exercise. During the first week, the patient’s arm may be continuously immobilized because of pain and muscle guarding. An older, less active patient (over 40 years of age) may require immobilization for only 2 weeks. The position of dislocation must be avoided when exercising, when dressing, or doing other daily activities.
Promote Tissue Health
Use protected ROM, intermittent muscle setting of the rotator cuff, deltoid, and biceps brachii muscles, and grade II joint techniques.
Precautions: In order not to disrupt healing of the capsule and other damaged tissues after anterior dislocation, ROM into external rotation is performed with the elbow at the patient’s side, with the shoulder flexed in the sagittal plane, and with the shoulder in the resting position (in the plane of the scapula, abducted 55 degrees and 30 to 45 degrees anterior to the frontal plane), but not in the 90-degree abducted position. The forearm is moved from in front of the trunk (maximal internal rotation) to 0 or possibly 10 to 15
degrees external rotation. Extension beyond 0 degrees is contraindicated. Intermittent muscle setting of the rotator cuff, deltoid, and biceps brachii muscles Grade II joint techniques: Maintain joint play by using sustained grade II distraction or gentle grade II oscillations with the glenohumeral joint at the side or in the resting position.
Management: Controlled Motion Phase After Closed Reduction of Anterior Dislocation
Provide Protection
The patient continues to wear the sling for 3 weeks, then increases the time the sling is off; the sling is used when the shoulder is tired or if protection is needed.
Increase Shoulder Mobility
Begin mobilization techniques using all appropriate glides except the anterior glide. The anterior glide is contraindicated even though external rotation is necessary for functional elevation of the humerus. To safely stretch for external rotation, place the shoulder in the resting position (abducted 55 degrees and horizontally adducted 30 degrees), then externally rotate it to the limit of its range, and then apply a grade III distraction force perpendicular to the treatment plane in the glenoid fossa.
Passively stretch the posterior joint structures with horizontal adduction self-stretching techniques.
Increase Stability and Strength of Rotator Cuff and Scapular Muscles
Both the internal and external rotators need to be strengthened as healing occurs. The internal rotators and adductors must be strong to support the anterior capsule. The external rotators must be strong to stabilize the humeral head against anterior translating forces and to participate in the deltoid-rotator cuff force couple when abducting and laterally rotating the humerus. Scapular stability is important for normal shoulder function. Begin with isometric resistance exercises with the joint positioned at the side and progress to various pain-free positions within the available ranges. Initiate closed-chain, partial weight-bearing, and stabilization exercises. Progress to dynamic resistance, limiting external rotation to 50 degrees and avoiding the position of dislocation. At 3 weeks, begin supervised isokinetic resistance for internal rotation and adduction at speeds 180 degrees per second or higher. Position the patient standing with the arm at the side or in slight flexion and elbow flexed 90 degrees. The patient performs internal rotation beginning at the zero
Mobilizing to increase external rotation when an anterior glide is contraindicated.
Place the shoulder in resting position, externally rotate it, then apply a grade III distraction force. position with the hand pointing anteriorly and moving across the front of the body. Progress to positioning the shoulder at 90 degrees flexion, then perform the exercise from zero to full internal rotation. Do not position in 90 degrees abduction.
By 5 weeks, all shoulder motions are incorporated into exercises on isokinetic or other mechanical equipment except in the position of 90 degrees abduction with external rotation.
Return to Function Phase After Anterior Shoulder Dislocation
Restore Functional Control
Develop a balance in strength of all shoulder and scapular muscles. Develop coordination between scapular and arm motions. Develop endurance for each exercise as previously described for shoulder instabilities.
As stability improves, progress eccentric training to maximum load, increase speed and control, and progress to simulating desired functional patterns for activity.
Return to Maximum Function
Help the patient learn to recognize signs of fatigue and impingement and stay within the tolerance of the tissues. The patient can return to normal activities when there is no muscle imbalance, when good coordination of skill is present, and when the apprehension test is negative. Full rehabilitation takes 2 1/2 to 4 months.
Management After Posterior Dislocation of the Shoulder with Closed Reduction
The management approach is the same as anterior dislocation with the exception of avoiding the position of flexion with adduction and internal rotation during the acute and healing phases.
Protect the Part
The arm is immobilized. A sling may be uncomfortable because of the adducted and internally rotated position, particularly if the sling elevates the humerus so the head translates in a superior and posterior direction. The patient may be more comfortable with the arm hanging freely in a dependent position while kept immobile.
Increase Limited Ranges
Begin joint mobilization techniques using all appropriate glides except the posterior glide. Posterior glide is contraindicated. If adhesions develop, preventing internal rotation, mobility can safely be regained by placing the shoulder in the resting position (abducted 55 degrees and horizontally adducted 30 degrees), internally rotating it to the limit of its range, and then applying a grade III distraction force perpendicular to the treatment plane in the glenoid fossa with the arm internally rotated.