Common Shoulder Conditions

Question 1

Which is the most commonly dislocated joint?

Answer 1

Glenohumeral joint

Question 2

Why is the humeral head relatively prone to dislocation?

Answer 2

Relatively small/shallow glenoid cavity, supplemented only by less robust fibrocartilaginous glenoid labrum and ligamentous support

Question 3

What is the most common direction of shoulder dislocation?

Answer 3

• Anterior dislocation (95% cases)

- Always anteroinferior as superior movement of humeral head is prevented by the coraco-acromial arch

Question 4

In what position would a patient with anterior shoulder dislocation hold his arm?

Answer 4

Rotated laterally

Question 5

What complications may occur after anterior shoulder dislocation?

Answer 5

1. Tearing of anteroinferior glenoid labrum - joint susceptible to recurrent dislocations.
2. Injury to axillary nerve by direct compression of humeral head on nerve inferiorly as it passes through quadrangular space - causes deltoid paralysis and loss of sensation over regimental badge area.
3. “Lengthening” effect of humerus may stretch the radial nerve (tightly bound within radial groove) - produces radial nerve paralysis

Question 6

State two ‘common’ causes of posterior dislocation of the shoulder.
In what position would the patient typically hold his arm?

Answer 6

Electric shock and epileptic fit

Causes internal rotation of arm

Question 7

When is an acromioclavicular joint dislocation considered more serious?

Answer 7

If ligamental rupture occurs - especially coracoclavicular ligaments as weight of upper limb is not supported and shoulder moves inferiorly.
May require ligament reconstruction surgery.

Question 8

What is the most commonly fractured bone in the body? What do fractures commonly result from?

Answer 8

Clavicle fracture - often caused by fall on the shoulder or onto outstretched hand.

Question 9

Where on the bone do most clavicular fractures occur?

Answer 9

In middle third, or at junction of middle and lateral thirds.

Question 10

How are the ends of the clavicle displaced after fracture? Explain why.

Answer 10

• Lateral end displaced inferiorly by weight of arm and medially by pectoralis major.
• Medial end displaced superiorly by sternocleidomastoid muscle.

Question 11

Brachial plexus injuries after clavicular fractures are rare but a careful neurological examination should always be performed. Which parts of the brachial plexus are at most risk of injury?

Answer 11

The nerve divisions (as are directly posterior to clavicle)

Question 12

Which nerves may be damaged by upwards movement of the medial part of a clavicular fracture? What arm position would this damage result in?

Answer 12

Suprascapular nerves (medial, intermediate and lateral).

These nerves innervate lateral rotators of the upper limb at shoulder - damage results in unopposed medial rotation of upper limb (“waiters tip” position)

Question 13

How would you assess a patient for damage to the brachial plexus caused by a clavicular fracture.

Answer 13

With patient’s eyes closed, assess their ability to feel light touch (e.g. Cotton wool) and sharp touch in relevant dermatomes.

Question 14

What is calcific tendinitis?

Answer 14

Tendinitis characterised by deposits of hydroxyapatite in any tendon of the body but most commonly in tendons of rotator cuff.

Question 15

What causes acute calcific tendinitis? How does this present?

Answer 15

Bursting of calcium hydroxyapatite deposit.

2 day history, rapidly progressive pain (10/10 severity), resolves in 1-2 weeks.

Question 16

What causes a popeye deformity?

Answer 16

Rupture of tendon of long head of biceps brachii.

Usually results from wear and tear of inflamed tendon in bicipital groove (prolonged tendinitis).

Question 17

What is adhesive capsulitis? What is an alternative name for this condition?

Answer 17

Frozen shoulder = adhesive fibrosis and scarring between the inflamed GH joint capsule, rotator cuff, subacromial bursa and deltoid.
Seen in individuals 40-60 yo.

Question 18

What are the symptoms of adhesive capsulitis?

Answer 18

Symptoms:

• severe, progressive, nocturnal pain, with extreme jerk pain
• progressive stiffness follows
• resolves after 2-3 years

Question 19

Name some possible treatments for adhesive capsulitis?

Answer 19

1. Distension arthrography
2. Manipulation under anaesthesia
3. Surgical release

Question 20

What is a rotator cuff tear? What are the symptoms?

Answer 20

Tear in 1 or more of the tendons of the rotator cuff muscles (supraspinatus most common).

Symptoms:

• impingement signs
• weakness of affected muscle
• progressive functional loss with size of tear, e.g. complete tear of rotator cuff causes loss of function of supraspinatus muscle so the person cannot initiate abduction of the upper limb.

Question 21

How can surgical repair of a rotator cuff tear be enhanced?

Answer 21

augmentation with allograft

Question 22

What is rotator cuff arthropathy, in whom is it likely to occur and what is a possible treatment?

Answer 22

Combination of GH arthritis and rotator cuff tears.

Occurs in the elderly.

Treatment options include partial joint replacement with a cuff tear arthropathy prothesis or a reverse anatomy shoulder replacement in severe joint instability.

Question 23

What are the signs and symptoms and treatment options of acromioclavicular osteoarthritis?

Answer 23

Signs and symptoms:

• maj are asymptomatic
• high painful arc (i.e. during abduction)
• positive scarf test
• tender joint
• x-ray/US scan/MRI

Treatment options:

• NSAIDs
• Steroid injection (diagnosis/treatment)
• Arthroscopic or open excision of lateral clavicle (remove 1 cm off end)

Question 24

What are the signs and symptoms and treatment options of glenohumeral osteoarthritis?

Answer 24

Signs and symptoms:

• progressive pain and stiffness over years
• crepitus

Treatment options:

• analgesia and exercises
• steroid injections
• eventually joint replacement (hemi/TSR/short stem/surface)

Question 25

Which movements are difficult for someone with adhesive capsulitis?

Answer 25

- Difficulty abducting arm (can obtain apparent abduction of 45 degrees by elevating and rotating the scapula). - Because of lack of movement at GH joint, strain is placed on AC joint - may be painful during other movements (e.g. elevation of shoulder).

Question 26

Which injuries may initiate acute capsulitis?

Answer 26

GH dislocations, calcific supraspinatus tendinitis, partial tearing of rotator cuff and bicipital tendinitis.

Question 27

What is shoulder impingement syndrome? What can cause this?

Answer 27

Narrowing of the subacromial space, trapping the rotator cuff tendon. Possible causes: - bone spurs under acromion - swelling/thickening of rotator cuff tendon - bursitis = inflammation of bursa (fluid-filled sac lying between rotator cuff tendon and acromion) - calcific tendinitis

Question 28

What are the signs and symptoms, and possible treatments of shoulder impingement?

Answer 28

Signs and symptoms: - low painful arc (pain on abduction up to 90 degrees) - positive Hawkins test - US scan (for bursitis, tendinopathy and dynamic impingement) Treatment options: - steroids and physiotherapy - surgical decompression

Question 29

Which nerve is most likely to be injured in mid-shaft humeral fractures and why?

Answer 29

Radial nerve which runs in radial groove

Question 30

What is the effect of radial nerve damage from a mid-humeral break on movement at the elbow, wrist and fingers?

Answer 30

- Early branch of radial nerve involved in triceps innervation but branches of superior to mid-humeral break so little effect on elbow movement. - Radial nerve involved in innervation of wrist extensors so might see wrist drop.

Question 31

In a proximal clavicular fracture, auscultation of the chest must be performed and a chest X-ray may also be needed. What rare but important complication needs to be excluded?

Answer 31

Pneumothorax - risk of lung puncture