Common Shoulder Conditions Flashcards
Which is the most commonly dislocated joint?
Glenohumeral joint
Why is the humeral head relatively prone to dislocation?
Relatively small/shallow glenoid cavity, supplemented only by less robust fibrocartilaginous glenoid labrum and ligamentous support
What is the most common direction of shoulder dislocation?
- Anterior dislocation (95% cases)
- Always anteroinferior as superior movement of humeral head is prevented by the coraco-acromial arch
In what position would a patient with anterior shoulder dislocation hold his arm?
Rotated laterally
What complications may occur after anterior shoulder dislocation?
- Tearing of anteroinferior glenoid labrum - joint susceptible to recurrent dislocations.
- 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.
- “Lengthening” effect of humerus may stretch the radial nerve (tightly bound within radial groove) - produces radial nerve paralysis
State two ‘common’ causes of posterior dislocation of the shoulder.
In what position would the patient typically hold his arm?
Electric shock and epileptic fit
Causes internal rotation of arm
When is an acromioclavicular joint dislocation considered more serious?
If ligamental rupture occurs - especially coracoclavicular ligaments as weight of upper limb is not supported and shoulder moves inferiorly.
May require ligament reconstruction surgery.
What is the most commonly fractured bone in the body? What do fractures commonly result from?
Clavicle fracture - often caused by fall on the shoulder or onto outstretched hand.
Where on the bone do most clavicular fractures occur?
In middle third, or at junction of middle and lateral thirds.
How are the ends of the clavicle displaced after fracture? Explain why.
- Lateral end displaced inferiorly by weight of arm and medially by pectoralis major.
- Medial end displaced superiorly by sternocleidomastoid muscle.
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?
The nerve divisions (as are directly posterior to clavicle)
Which nerves may be damaged by upwards movement of the medial part of a clavicular fracture? What arm position would this damage result in?
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)
How would you assess a patient for damage to the brachial plexus caused by a clavicular fracture.
With patient’s eyes closed, assess their ability to feel light touch (e.g. Cotton wool) and sharp touch in relevant dermatomes.
What is calcific tendinitis?
Tendinitis characterised by deposits of hydroxyapatite in any tendon of the body but most commonly in tendons of rotator cuff.
What causes acute calcific tendinitis? How does this present?
Bursting of calcium hydroxyapatite deposit.
2 day history, rapidly progressive pain (10/10 severity), resolves in 1-2 weeks.
What causes a popeye deformity?
Rupture of tendon of long head of biceps brachii.
Usually results from wear and tear of inflamed tendon in bicipital groove (prolonged tendinitis).
What is adhesive capsulitis? What is an alternative name for this condition?
Frozen shoulder = adhesive fibrosis and scarring between the inflamed GH joint capsule, rotator cuff, subacromial bursa and deltoid.
Seen in individuals 40-60 yo.
What are the symptoms of adhesive capsulitis?
Symptoms:
- severe, progressive, nocturnal pain, with extreme jerk pain
- progressive stiffness follows
- resolves after 2-3 years
Name some possible treatments for adhesive capsulitis?
- Distension arthrography
- Manipulation under anaesthesia
- Surgical release
What is a rotator cuff tear? What are the symptoms?
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.
How can surgical repair of a rotator cuff tear be enhanced?
augmentation with allograft
What is rotator cuff arthropathy, in whom is it likely to occur and what is a possible treatment?
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.
What are the signs and symptoms and treatment options of acromioclavicular osteoarthritis?
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)
What are the signs and symptoms and treatment options of glenohumeral osteoarthritis?
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)
Which movements are difficult for someone with adhesive capsulitis?
- 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).
Which injuries may initiate acute capsulitis?
GH dislocations, calcific supraspinatus tendinitis, partial tearing of rotator cuff and bicipital tendinitis.
What is shoulder impingement syndrome? What can cause this?
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
What are the signs and symptoms, and possible treatments of shoulder impingement?
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
Which nerve is most likely to be injured in mid-shaft humeral fractures and why?
Radial nerve which runs in radial groove
What is the effect of radial nerve damage from a mid-humeral break on movement at the elbow, wrist and fingers?
- 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.
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?
Pneumothorax - risk of lung puncture
