Session 7: Common Shoulder Conditions

Question 1

Mechanism of injury of fractures of the scapula.

Answer 1

High speed road collisions Crushing injuries High-impact sport injuries

Question 2

Mechanism of injury of fracture of the surgical neck of the humerus.

Answer 2

Blunt trauma to shoulder or FOOSH Falling on outstretched hand

Question 3

Complications of fracture of the surgical neck of the humerus.

Answer 3

Key neuromuscular structures at risk like the axillary nerve and posterior circumflex artery. Axillary nerve damage will result in paralysis of the deltoid and teres minor muscles. Patient will have difficulty performing abduction of the affected limb. Nerve also innervates the skin in the regimental badge area.

Question 4

Mechanism of injury of rupture of biceps tendon.

Answer 4

Commonly in patients over 50 yrs. Minimal trauma Patient hears a snap in the shoulder while lifting.

Question 5

Clinical presentation of rupture of biceps tendon.

Answer 5

Flexion of the arm at the elbow produces a firm lump in the lower part of the arm. This is the unopposed contracted muscle belly of the biceps and this is called Popeye sign. Patient will not notice much weakness in the upper limb due to the action of the brachialis and supinator muscles.

Question 6

Most common form of dislocation of the shoulder.

Answer 6

Anterior shoulder dislocation.

Question 7

Why is anterior shoulder dislocation most common?

Answer 7

Even though the joint is strengthened anteriorly the shoulder usually dislocates anteriorly. This is because the head of the humerus usually dislocated anteroinferiorly but then displaces in an anterior direction. This is because of the pull of the muscles and the disruption of the anterior capsule and ligaments.

Question 8

Clinical presentation of anterior shoulder dislocation.

Answer 8

Arm is held in a position of external rotation and slight abduction. Visibly deformed and there can be visible swelling and bruising. Movement will be severely restricted and painful.

Question 9

Explain how the anterior shoulder dislocation happens.

Answer 9

The first episode usually occurs when the patient has their arm positioned in abduction and external rotation like hand behind the head. The next step is an unexpected small further injury forcing the arm a little further posteriorly pushing the shoulder into an extreme position. The humeral head dislocates antero-inferiorly from the glenoid. It can also happen in a direct blow to the posterior shoulder.

Question 10

Complications of anterior shoulder dislocation.

Answer 10

Bankart lesion/Labral tear Hill-Sachs lesion

Question 11

What is Bankart lesion?

Answer 11

When the humeral head pops out of the socket the force causes a part of the glenoid labrum to be torn off.

Question 12

What is Hill-Sachs lesion?

Answer 12

When the humeral head dislocates anteriorly, the tone of the infraspinatus and teres minor muscles means that the posterior aspect of the humeral head becomes jammed against the anterior lip of the glenoid fossa.

This can cause a dent in the posterolateral humeral head known as Hill-Sachs lesion.

Question 13

Causes of posterior dislocation.

Answer 13

Violent muscle contractions due to epileptic shock.

Electrocution or lightning strike.

Blow to the anterior shoulder or when the arm is flexed across the body and pushed posteriorly.

Question 14

Clinical presentation of posterior dislocation of the shoulder.

Answer 14

Patients usually present with their arm internally rotated and abducted (compared to anterior which is external rotation and abducted).

Flattening/squaring of the shoulder with a prominent coracoid process.

Arm cannot be externally rotated into the anatomical position.

Question 15

Common complications of posterior shoulder dislocation.

Answer 15

Fractures

Rotator cuff tears

Hill-Sachs lesion

Question 16

Mechanism of injury of inferior dislocation of the shoulder.

Answer 16

After inferior dislocation the head of the humerus sits inferior to the glenoid.

Forceful traction on the arm when it is fully extended over the head. An example is grasping an object above the head to break a fall also called hyperabduction injury.

Question 17

Injuries associated with inferior shoulder dislocation.

Answer 17

Damage to nerves (60%)

Rotator cuff tears (80%)

Injury to blood vessels. (3%)

Question 18

Most common complication of shoulder dislocation in any direction.

Answer 18

Recurrent dislocation due to damage to the stabilising tissues surrounding the shoulder.

Question 19

Other complications that can occur in shoulder dislocations.

Answer 19

Bankart Lesion

Hill-Sachs Lesion

Damage to axillary artery

Damage to axillary nerve leading however it is uncommon for the damage to be permanent. Most people have full axillary nerve recovery.

Cords of the brachial plexus damage can also occur as well as musculocutaneous damage but it is less common.

Fractures to the humeral head, greater tubercle, clavicle and acromion can also happen.

Rotator cuff muscle tears can also happen and are especially common in inferior dislocation.

Question 20

Mechanism of injury of clavicle fractures.

Answer 20

Peak age is children and young adults.

Usually fall onto the affected shoulder or fall onto an outstretched hand (FOOSH).

Question 21

Where on the clavicle is it most common to get a fracture?

Answer 21

In the middle third of the clavicle (80%)

Question 22

Treatment of clavicle fractures.

Answer 22

Usually conservatively.

However there are some indications that suggest that surgical fixation is required.

Question 23

What indications suggest surgical fixation of clavicle fracture?

Answer 23

Complete displacement

Severe displacement where you can see a part of the clavicle through the skin.

Open fractures

Neurovascular compromise

Fractures with interposed muscle

Floating shoulder where there is a clavicle fracture with ipsilateral fracture of glenoid neck.

Question 24

What will happen to the position of the arm and clavicular fragments in a displaced mid-clavicular fracture?

Answer 24

Sternocleidomastoid muscle elevates the medial segment.

Trapezius muscle is unable to hold the lateral segment up because of the weight of the upper limb so the shoulder will drop.

The arm is pulled medially by pectoralis by adduction.

Question 25

Complications of clavicle fractures.

Answer 25

Many associated with the healing process.

Non-union where there is failure to unite the fractured bones.

Malunion uniting in a suboptimal position.

Pneumothorax

Injury to surrounding neurovascular structures.

Suprascapular nerve injury.

Supraclavicular nerves may also be damaged resulting in paraesthesia over the upper chest anteriorly.

Question 26

What is a rotator cuff tear?

Answer 26

A tear of one ore more of the tendons of the four rotator cuff muscles of the shoulder.

Question 27

What part of the rotator cuff muscles are most commonly torn?

Which rotator cuff muscle is most commonly torn?

Answer 27

The tendons.

Supraspinatus tendon where it passes beneath the coracoacromial arch tearing at the site of its insertion onto the greater tubercle of the humerus.

Question 28

Mechanism of injury of rotator cuff tear.

Answer 28

Acute tears can happen like in a shoulder dislocation but it is uncommon with acute tears.

Chronic tears are much more common. They happen due to a combination of factors like poor biomechanics or muscular imbalance. It is an age-related degeneration where as you get older tendons will not be as readily supplied with blood and nutrients so small injuries will not heal properly. Repeated partial tendon tears will lead to a full tear eventually.

Inflammatory cells are recruited and oxidative stress leads to tenocyte apoptosis. Leading to further degeneration and this leads to a vicious circle.

Question 29

Other risk factors of rotator cuff tears.

Answer 29

Recurrent lifting and repetitive overhead activity like for carpenters and painters.

Sports that involve repeated overhead motion like swimming, volleyball, tennis and weightlifting.

Question 30

Clinical presentation of rotator cuff tears.

Answer 30

Most are asymptomatic but the most common presentation is anterolateral shoulder pain often radiating down the arm.

Pain in the shoulder when they lean on their elbow and push downwards.

Pain in the shoulder when reaching forward.

Also weakness of shoulder abduction.

Question 31

Treatment of rotator cuff tears.

Answer 31

Can be conservative or operative.

Question 32

What is impingement syndrome?

Answer 32

When the supraspinatus tendon impinges/rubs/catches on the coraco-acromial arch leading to irritation and inflammation.

Question 33

Causes of impingement syndrome.

Answer 33

Anything that narrows the space further (the space between the head of the humerus and the coracoacromial arch) also called subacromial space.

This can be thickening** of the coracoacromial ligament, **inflammation** of the supraspinatus tendon or **subacromial osteophytes in OA.

Question 34

Signs and symptoms of impingement syndrome.

Answer 34

Pain, weakness and reduced range of motion.

Pain often worsened by shoulder overhead movement and may also occur at night especially if the patient is lying on the affected shoulder.

Pain can be acute or gradual depending on the mechanism of injury. Pain described as dull rather than sharp and lingers for long periods of time.

Grinding** or **popping sensation.

Painful arc.

Question 35

What is the painful arc?

Answer 35

Abduction of the shoulder between 60-120 degrees of abduction is very painful. Below 60 degrees and above 120 degrees there is no pain or significantly less.

Common in impingement syndrome.

Question 36

Treatment of impingement syndrome.

Answer 36

Treat underlying cause.

Question 37

What is this?

Answer 37

Calcific supraspinatus tendinopathy

Question 38

What is calcific supraspinatus tendinopathy?

Answer 38

Characterised by presence of macroscopic hydroxyapatite in the tendon of supraspinatus. Most common in supraspinatus.

Question 39

Signs and symptoms of calcific supraspinatus tendinopathy.

Answer 39

Acute or chronic pain often aggravated by abducting or flexing the arm above the level of the shoulder or by lying on the shoulder.

Mechanical symptoms can also occur due to the presence of large deposits of hydroxyapatite. These symptoms include stiffness**, **snapping sensation**, **catching** or **reduced range of movement of the shoulder.

Question 40

How does calcific supraspinatus tendinopathy occur?

Answer 40

Multifactorial and two main theories:

Regional hypoxia leads to tenocytes being transformed into chondrocytes and lay down cartilage. A process with similarities to endochondral ossification lays down calcium deposits.

Other theory is ectopic bone formation from metaplasia of mesenchymal stem cells -> osteogenic cells.

Question 41

When is calcific supraspinatus tendinopathy most painful?

Answer 41

When the calcific deposits are reabsorbed by phagocytes. During the reabsorption they look macroscopically like toothpaste and often appear cloud-like.

Question 42

Treatment of calcific supraspinatus tendinopathy.

Answer 42

Usually conservative or at least initially with rest and analgesia.

However if symptoms persist surgery will be considered.

Question 43

What is frozen shoulder? Also called adhesive capsulitis.

Answer 43

A painful disabling disored in which the capsule of the glenohumeral joint becomes inflamed and stiff.

Adhesion and scar tissue will form in the joint.

Question 44

Causes of adhesive capsulitis + risk factors.

Answer 44

Unknown cause but many believe there is an autoimmune component to the disease.

Risk factors:

Female gender
Epilepsy with tonic seizures
Diabetes mellitus
Trauma to shoulder
Connective tissue disease
Thyroid disease (hypo and hyperthyroidism)
Cardiovascular disease
Chronic lung disease
Breast cancer
Polymyalgia rheumatica
Parkinson’s disease

Long periods of inactivity can precipitate frozen shoulder and it can occur along other shoulder problems like calcific supraspinatus and rotator cuff tears.

Question 45

Signs and symptoms of frozen shoulder.

Answer 45

Stiffness

Restriction of movement

Chronic pain

Pain usually constant and worse during night.

Sleep deprivation due to the pain and some might develop depression.

Question 46

Treatment of frozen shoulder.

Answer 46

Physiotherapy, analgesia and anti-inflammatory medication.

Patients can sometimes undergo manipulation under anaesthesia which breaks up the adhesions and scar tissue in the joint to help restore range of motion.

Question 47

In which joint of the shoulder does osteoarthritis most commonly occur?

Answer 47

Affect the acromioclavicular joint

Most commonly occur in people over 50 years of age.

Question 48

Treatment of OA of acromioclavicular joint.

Answer 48

Treatment ladder.

First conservatively and then if needed surgery.

Question 49

Conservative treatment of OA of acromiaclavicular joint.

Answer 49

Activity modification, analgesia and anti-inflammatories (NSAIDS).
Nutritional supplements like glucosamine and chondroitin sulfate.

Steroid injections can be used and injected into the joint to reduce swelling and thereby alleviate symptoms.

Hyaluronic acid can also be injected into the joint in order to increase lubrication however evidence for this is limited.

Question 50

Surgical treatment of OA of acromioclavicular joint and glenohumeral joint.

Answer 50

Arthroscopy by keyhole surgery can be performed to remove loose pieces of damaged cartilage.

Some patients might need hemiarthroplasty which is replacement of the humeral head.

Total shoulder replacement which is replacement of the humeral head and also the glenoid.