Introduction to common injuries (and surgery) of the shoulder Flashcards
Where does shoulder pain rank in the top 10 musculoskeletal pain that GPs see?
- 3rd most common
The mnemonic SIT.s can be used to identify 3 of the 4 rotator cuff muscles that attach to the greater tubercle, which is the medial of the lesser and greater tubercle, as we can see in the image below. What muscles does SIT refer to and where does the 4th muscle the s in SIT.s mean and where does it insert?
- S = Supraspinatus
- I = Infraspinatus
- T = Teres minor
- s = subscapularis inserts on lesser tubercle
Label the 3 muscles that attach to the lesser crest of the greater and lesser tubercle and bicipital groove in the image, the mnemonic a ‘Lady between 2 Majors may help?
- Lady = latissimus dorsi
- Major 1 = teres major (crest of lesser tubercle, medially)
- Major 2 = pectoralis major (crest of greater tubercle, laterally)
The glenohumeral joint is not a very stable joint and therefore it requires a number of structures to stabilise the joint. These can be divided into dynamic and static stabilisers. Of the structures listed here, which 4 are classed as static stabilisers?
Joint capsule Subscapularis (internal rotator) Teres minor (external rotator) Glenohumeral ligaments Bony glenoid Labrum Infraspinatus (two heads and external rotator) Supraspinatus (abduction)
1 = Joint capsule 2 = Glenohumeral ligaments 3 = Bony glenoid 4 = Labrum
The glenohumeral joint is not a very stable joint and therefore it requires a number of structures to stabilise the joint. These can be divided into dynamic and static stabilisers. Of the structures listed here, which 4 are classed as dynamic stabilisers?
Joint capsule Subscapularis (internal rotator) Teres minor (external rotator) Glenohumeral ligaments Bony glenoid Labrum Infraspinatus (two heads and external rotator) Supraspinatus (abduction)
1 = Subscapularis (internal rotator) 2 = Teres minor (external rotator) 3 = Infraspinatus (two heads and external rotator) 4 = Supraspinatus (abduction)
The labrum is a static stabiliser of the glenohumeral joint. What is the labrum and how does aid with joint stability?
- fibrocartilaginous tissue (not hyaline)
- surrounds bony glenoid and adds 50% deepness adding to stability
What are the 4 major extrinsic muscles of the shoulder? 3 of which can be remembered using the mnemonic ‘Lady between 2 Majors’?
1 - Lady = Latissimus Dorsi
2 - Major 1 = Teres Major
3 - Major 2 = Pectoralis Major
4 - deltoid
What are the major movements of each of the following muscles:
Latissimus Dorsi
Teres Major
Pectoralis Major
Deltoid
- Latissimus Dorsi = adduction and internal rotation
- Teres Major = adduction, extension and internal rotation
- Pectoralis Major = flexion and internal rotation
- Deltoid = abduction
What is the most common dislocation of the shoulder joint?
- anterior dislocation
Who is anterior shoulder location most common in?
- men <30 years old
- if one dislocation then more likely to re-occur (90%)
Marfans disease can cause shoulder instability. What is Marfans disease?
1 - congenital disorder of bones
2 - congenital disorder of muscles
3 - congenital disorder of all connective tissue
4 - congenital disorder of cartilage
3 - congenital disorder of connective tissue
- leads to weakness in joints and instability
In addition to ligamentous laxity, what is the next common cause of shoulder instability?
- tear of the labrum or capsule
- labrum normally deepens the glenoid cavity
What is a Bankart lesion?
1 - tear of coronoid ligament, causes glenoid instability
2 - tear of labrum, where labrum comes away from the glenoid bone
3 - tear of acromioclaviculuar ligament, causes glenoid instability
4 - rupture of labrum, where labrum comes away from the glenoid bone
2 - tear of labrum, where labrum comes away from the glenoid bone
What is a Hill-sachs lesions? (think Hill and Humerus, both begin with H)
- a lesion, bone loss, defect and/or deformity of the humeral head
- affects range of motion and stability
What is multidirectional shoulder instability?
- patient has shoulder instability in multiple planes (anterior, posterior etc…)
Multidirectional shoulder instability is when a patient has instability in multiple planes. What repetitive action can lead to multidirectional shoulder instability?
- overhead actions
- swimmers, gymnasts, overhead throwers)
Posterior dislocations are much less common than anterior dislocations. What is the most common cause of a posterior shoulder dislocation?
- high energy trauma
- electrocution
- seizures
The X-ray image shows a shoulder injury that can be described as a lightbulb sign is what type of shoulder injury?
- posterior dislocation
- humerus has completely internally rotated, greater tuberosity cannot be seen
Luxatio erecta is the rarest form of shoulder dislocation, accounting for <0.5% of all shoulder dislocations. What is a Luxatio erecta type of dislocation?
1 - true medial dislocation
2 - true lateral dislocation
3 - true inferior dislocation
4 - true superior dislocation
3 - true inferior dislocation
Luxatio erecta is the rarest form of shoulder dislocation, which is a true inferior dislocation of the shoulder, accounting for <0.5% of all shoulder dislocations. Although this is a serious injury and it is rare, this can be a very dangerous injury as what structures can be damaged?
1 - axillary artery and nerve
2 - axillary vein and artery
3 - brachial plexus and axillary artery
4 - brachial plexus only
3 - brachial plexus and axillary artery
Glenohumeral osteoarthritis is a rarely common cause of shoulder pain as we age. What are the 5 most common symptoms of osteoarthritis?
- stiffness
- grinding & crepitis
- night pain/ rest pain
- pain related to activity
- restricted range of motion
Glenohumeral osteoarthritis is a rarely common cause of shoulder pain as we age. The 5 most common symptoms of osteoarthritis are as follows:
- stiffness
- grinding & crepitis
- night pain/ rest pain
- pain related to activity
- restricted range of motion
What are the 4 main things that happen to the glenohumeral joint in osteoarthritis?
- loss of joint space
- subchondral (bone underneath cartilage) sclerosis (thickening of the bone)
- osteophyte formation (bony spurs)
- bone cyst formation
What is the most common cause of shoulder pain?
1 - tear of glenoid labrum
2 - rheumatoid arthritis
3 - osteoarthritis
4 - subacromial impingement
4 - subacromial impingement
Subacromial impingement is the most common cause of shoulder pain, and is when something causes the subacromial space to become smaller. There is one muscle that passes through the subacromial space and attaches to greater tubercle of the humerus and is often one of the major causes of subacromial impingement. What muscle is this?
1 - long head of biceps brachii
2 - teres minor
3 - infraspinatus
4 - supraspinatus
4 - supraspinatus
- origin is supraspinous fossa of scapula
- inserts onto the greater tubercle of the humerus
Subacromial impingement is the most common cause of shoulder pain, and is when something causes the subacromial space to become smaller. Patients generally report that they experience pain when lifting their arms above their heads in an arc between 70-120 degrees, why is this?
- lifting the arm is abduction
- abduction forces the greater tuberosity into the subacromial space
- therefore makes pain appear worse
- can use Neers Test for this
Subacromial impingement is the most common cause of shoulder pain, and is when something causes the subacromial space to become smaller. Does this always require surgery?
- no often gets better alone
- steroid injections and physio can help
Subacromial impingement is the most common cause of shoulder pain, and is when something causes the subacromial space to become smaller. Although a lot of the time these do resolve alone, what generally happens if the patient has surgery called arthroscopic surgery?
- shave away part of the bone of the acromion or bursa to make space bigger
What is frozen shoulder?
- loss of active and passive movement (especially external rotation)
- associated with stiffness and pain
What causes frozen shoulder?
1 - trauma to the shoulder
2 - inflammation and fibroblasts deposition
3 - trauma followed by inflammation and fibroblasts deposition
4 - Iigament damage
2 - inflammation and fibroblasts deposition
- fibroblasts invade the capsule forming a mechanical block
- results in reduced ROM and pain
What are the 4 most common risk factors for frozen shoulder?
1 - female, middle years (40-60), diabetes, hypothyroidism
2 - male, young years (20-30), diabetes, hypothyroidism
3 - female, middle years (40-60), diabetes, hyperthyroidism
4 - male, middle years (40-60), diabetes, hyperthyroidism
1 - female, middle years (40-60), diabetes, hypothyroidism
Frozen shoulder is caused by inflammation of the shoulder capsule, allowing fibroblasts to invade the capsule forming a mechanical block. This results in reduced ROM and pain. There are 3 phases from onset to resolution, what are they?
1st Freezing pain phase - gradual onset of diffuse (broad) pain
2nd Frozen and stiff pain - gradual reduction in ROM and reduced activity
3rd Thawing phase - gradual resolution of pain and ROM
Frozen shoulder is caused by inflammation of the shoulder capsule, allowing fibroblasts to invade the capsule forming a mechanical block. This results in reduced ROM and pain. There are 3 phases from onset to resolution:
1 - gradual onset of diffuse (broad) pain
2 - gradual reduction in ROM and reduced activity
3 - gradual resolution of pain and ROM
Generally how long does each phase last and how long until resolution?
1st stage = 6 weeks to 9 months
2nd stage = 4-9 months
3rd stage = 5-26 months
- normally resolves within 2 years
What are the common treatments for frozen shoulder?
- NSAIDs
- physio
- corticosteroid injections
Rotator cuff tears are when one of the 4 rotator cuff muscles has torn off its attachment from the glenohumeral joint. These can be divided into 2 categories based on who this happens to. What are the 2 categories of tear?
1 - young and active patients with traumatic tears
2 -older, degenerative tears (FT tears >60 yrs = 25%, >70 yrs = 60%).
Rotator cuff tears are when one of the 4 rotator cuff muscles has torn off its attachment from the glenohumeral joint. In younger patients with high trauma, which muscle of the rotator cuffs is most likely to avulse?
1 - supraspinatus
2 - infraspinatus
3 - teres minor
4 - subscapularis
4 - subscapularis
Rotator cuff tears can occur in young athletic or older patients and can be partial or full tears. What are the 5 most common risk factors for rotator cuff tears?
- age
- diabetes
- smoking
- hypercholesterolaemia
- family history of tears.
How are rotator cuff tears generally diagnosed?
- use provocative tests to elicit pain but imaging confirms diagnosis
If we have the extrinsic muscles that support the glenohumeral joint, why is a rotator cuff tear so important?
- increases pain and causes weakness
- reduces ROM
What is the normal progression of patients who are symptomatic or asymptomatic with rotator cuff tears?
- 50% asymptomatic, BUT become symptomatic after 2-3 years
- 50% symptomatic partial tears will progress and become worse
In young athletic patients, which of the 4 rotator cuff muscles below is most likely to tear?
S = Supraspinatus
I = Infraspinatus
T - Teres Minor
S = Subscapularis
- S = Subscapularis is most common
In patients >40 y/o, are patients more likely to tear the SIT or Subscapularis muscles?
- SIT
In degenerative tears, what happens to the tendons of the rotator cuffs that can weaken the rotator cuffs?
- fatty infiltration
- replaces the tendon with fat and is difficult to repair
In degenerative tears, tendons of the rotator cuffs that can weaken due to fatty infiltration that replaces the tendon with fat and is difficult to repair. Of the rotator cuff muscles below, which are most likely to be affected?
S = Supraspinatus
I = Infraspinatus
T - Teres Minor
S = Subscapularis
- any can be affected, but mainly SIT muscles on greater tuberosity
Chronic rotator cuff tears can eventually cause the humeral head to migrate north into a space causing what?
1 - fracture of humeral head
2 - reduced subacromial space and pain
3 - fracture of scapula
4 - fracture of surgical head of the humerus
2 - reduced subacromial space and pain
Chronic rotator cuff tears can eventually cause the humeral head to migrate north into a space causing reduced subacromial space and pain. This in turn can then lead to what in the long term?
1 - glenohumeral joint arthritis
2 - frozen shoulder
3 - shoulder impingement
4 - fracture of the scapula
1 - glenohumeral joint arthritis
Once a patient has developed glenohumeral joint arthritis due to chronic rotator cuff tear, what becomes a viable treatment option?
- surgery with a reverse shoulder replacement
- salvage and not great surgery
What is the deltopectoral approach?
- incision is made from coracoid process along pectoral and deltoid margins
- common open surgical approach for the shoulder
The deltopectoral approach is a surgical approach for open shoulder surgery for access to the proximal head of the humerus. It is important to know the nerves that innervate the deltoid and pectoralis major, what nerve innervate the deltoid?
1 - ulnar
2 - radial
3 - musculocutaneous
4 - axillary
4 - axillary
The deltopectoral approach is a surgical approach for open shoulder surgery for access to the proximal head of the humerus. It is important to know the nerves that innervate the deltoid and pectoralis major, what nerve innervate the pectoralis major?
1 - axillary nerve
2 - radial nerve
3 - medial and lateral pectoral nerves
4 - long thoracic nerve
3 - medial and lateral pectoral nerves
Label the 3 key aspects surgeons will use to mark the incision site for a deltopectoral open shoulder surgical approach?
- deltoid
- corocoid process of scapula
- pectoralis major
1 = corocoid process of scapula 2 = deltoid 3 = pectoralis major
Once the patient has been opened during a deltopectoral open shoulder surgical approach, what vein sits between the deltoid and pectoralis major?
1 - radial vein
2 - axillary vein
3 - cephalic vein
4 - basilic vein
3 - cephalic vein
What is the most common form of humeral fracture?
1 - surgical neck
2 - humeral shaft
3 - anatomical neck
4 - humeral head
1 - surgical neck
- humeral head breaks off at surgical head
- 3rd most common fracture in the elderly
The most common form of humeral fracture is the surgical neck, which is the 3rd most common fracture in the elderly. What are the 5 most common risk factors for this occurring?
- age
- gender (female more likely)
- osteoporosis
- diabetes
- epilepsy
What is Guyons canal?
1 - a fibro-osseous tunnel located at the lateral level of the dorsum
2 - a fibro-osseous tunnel located at the medial level of the dorsum
3 - a fibro-osseous tunnel located at the medial level of the palm
4 - a fibro-osseous tunnel located at the lateral level of the palm
3 - a fibro-osseous tunnel located at the medial level of the palm
The Guyons canal is a fibro-osseous tunnel located at the medial level of the palm. What is the importance of this canal?
1 - allows passage of ulnar nerve and radial artery into hand
2 - allows passage of ulnar nerve and ulnar artery into hand
3 - allows passage of median nerve and radial artery into hand
4 - allows passage of ulnar nerve and median artery into hand
2 - allows passage of ulnar nerve and ulnar artery into hand
The Guyons canal is a fibro-osseous tunnel located at the medial level of the palm that allows passage of ulnar nerve and ulnar artery into hand. If this is compressed what can happen?
- leads to weakness in interossei muscles
- leads to weakness of little finger
- leads to weakness of thumb adduction
- sensory loss in half of digit 4 and all of digit 5
