Pathology of the Shoulder Flashcards
What is the proper name for the shoulder joint, and what surfaces are articulating with each other?
Glenohumeral joint
Humeral head and scapular glenoid
What are the rotator cuff muscles and why are they important?
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Provide stability to the shoulder joint as it is highly mobile
Supraspinatus - attachments, nerve innervation and function (along with clinical test)
Origin - supraspinous fossa of scalpula
Insertion - greater tubercle of humerus
Innervation - suprascapular nerve (C5)
Function - initiation of abduction
Test - Jobe’s Test (empty can test)
Infraspinatus - attachments, nerve innervation and function (along with clinical test)
Origin - infraspinous fossa of scapula
Insertion - greater tubercle of humerus
Innervation - subscapular nerve (C5)
Function - external rotation of shoulder
Test - resistance of external rotation
Teres Minor - attachments, nerve innervation and function (along with clinical test)
Origin - lateral border of scapula
Insertion - greater tubercle of humerus
Innervation - axillary nerve (C5-C6)
Function - also helps to externally rotate humerus
Subscapularis - attachments, nerve innervation and function (along with clinical test)
Origin - subscapular fossa
Insertion - lesser tubercle of the humerus
Innervation - upper and lower subscapular nerves (C5/C6)
Function - internal rotation
Test - “Gerber’s” Lift-Off test (hand behind back and push examiner’s hand)
What is the main cause of rotator cuff injuries in the following age groups…
- Younger patients
- Older patients
- Elderly patients
Younger - instability
Older - tears/frozen shoulder (grey hairs = tears)
Elderly = OA of glenohumeral joint
Which is the most commonly injured of the rotator cuff muscles?
Supraspinatus
Which is the predominant muscle involved in painful arc syndrome (shoulder impingement)?
What happens? What range of abduction does the patient typically have?
Predominant muscle involved is supraspinatus
The tendon of supraspinatus (and other rotator cuff muscles) are compressed in the tight subacromial space during movement
Patients typically have between 60 and 120 degrees of abduction
Shoulder impingement - signs/symptoms (as well as which test can be done to test for it!) and management
Signs/Symptoms
- Pain, typically radiating to deltoid and upper arm
- Tenderness below the lateral edge of the acromion
The Hawkin’s-Kennedy Test assesses shoulder impingement - internal rotation of the flexed shoulder recreates pain
Management
- Rest, NSAIDs, physiotherapy, subacromial injections of steroids
- Persistent cases may require decompression surgery
What is the classic history of a rotator cuff tear?
Weakness in the following ranges of motion indicate what muslce tear?
- abduction
- external rotation
- internal rotation
Sudden jerking motion in a patient >40 years old, causing pain and weakness (nb - rotator cuff tears in younger patients can in theory occur, but they are very uncommon)
abduction - supraspinatus (most common)
external rotation - infraspinatus (and teres minor)
internal rotation - subscapularis
How is rotator cuff injury best managed?
Surgery/No surgery is debatable - 1/3rd of repairs are unsuccessful
Most do well with physiotherapy to strengthen up the remaining rotator cuff muscles and occasional subacromial injections
How long does frozen shoulder syndrome affect people?
What are the 3 phases?
Can affect people for 18-24 months! (variable)
- Initial freezing - 2-9 months
- Frozen - 4-12 months
- Thawing
What is the principle clinical sign associated with frozen shoulder syndrome?
Loss of external rotation
What are the two subtypes of shoulder instability?
Traumatic - aggressive anterior dislocation, usually settles and restabilises over time but sometimes recurrent dislocations develop
Atraumatic - due to e.g. ligamentous laxity (Ehlers-Danlos, Marfans, GJL)
What surgical repair method can be used to treat recurrent dislocations of a shoulder?
Bankart repair - reattaches the labrum and capsule to the anterior glenoid that was torn initially
What other pathology in the arm may result in shoulder pain?
What is the classic clinical sign of this condition?
Inflammation of the long head of the biceps brachii
Causes anterior shoulder pain when the biceps contracts
Tendon may also spontaneously rupture - this will relieve the symptoms of should pain but the patient will be left with a Popeye deformity
