Dislocated shoulder - 2
Important Good preparation and adequate sedation/analgesia make these easy.
Examination -anterior dislocation
1. Arm is held in slight abduction and external rotation
2. Shoulder is ‘squared off’ (ie box like) with loss of deltoid contour compared to contralateral side
3. Humeral head is palpable anteriorly beneath the clavicle
4. Patient resists abduction and internal rotation and is unable to touch the other shoulder
5. Compare bilateral radial pulses to rule out vascular injury
6. In all cases, examine the axillary nerve before and after reduction by testing both pinprick sensation in the lower area of the deltoid and palpable contraction of the deltoid during attempted abduction. Check sensory/motor function of the musculocutaneous and radial nerves.
Examination
Examination - posterior dislocation
1. Arm is held in adduction and internal rotation
2. Anterior shoulder is squared off and flat with prominent coracoid process. Shoulders may look identical in bilateral dislocation, making it a commonly missed injury.
3.Posterior shoulder is full with humeral head palpable beneath the acromion process.
4. Patient resists external rotation and abduction.
Neurovascular deficits are rare.
Examination - inferior dislocation
1. Arm is fully abducted with elbow commonly flexed on or behind head
2. Humeral head may be palpable on the lateral chest wall.
Tests
Shoulder trauma series - Anterioposterior (AP) and axillary or scapular “Y” views
Anterior dislocation
Is characterised by subcoracoid position of the humeral head in the AP view. The dislocation is often more obvious in a scapular “Y” view where the humeral head lies anterior to the ‘tee’ (ie, glenoid)
Posterior dislocation
The AP view may show a normal walking stick contour of the humeral head, or it may resemble a light bulb of icecream cone depending upon the degree of rotation. The scapular “Y” view reveals the humeral head behind the glenoid (the centre of the “Y”. In an axillary view, the ‘golfball’ fall posteriorly off the ‘tee’.
Inferior dislocation
The AP view may show the arm raised over the head with the radial head inferior to the glenoid.
Prereduction films document the nature of the dislocation and associated pathology, whilst postreduction films confirm relocation of the humerus and can reveal new or previous pathology.
1. Place a pillow between the patients arm and torso to increase comfort
2. Offer analgesia.(morphine, ketorolac)
3. Prereduction and postreduction radiographs are recommended. Patients with frequent recurrent dislocations rarely need X-rays.
4. Conscious sedation helps relax surrounding musculature, making reduction easier.
5. The key to successful reduction is slow and steady application of a maneuver with adequate analgesia and relaxation.
6. Successful reduction is evinced by a palpable or audible relocation, marked reduction in pain, and increased range of motion. The patient may be asked to touch the uninjured shoulder to safely demonstrate a successful reduction.
7. After all reductions, apply a shoulder immobiliser and perform a careful neurovascular examination.