Chronic Shoulder

Question 1

Describe the location of chronic shoulder pain for someone who participates in overhead arm movement

Answer 1

• lateral edge of acromiocn, pain shoots or aches into deltoid space, might get ache in posterior part of the scapula
• pain is aggravated in sports specific or ADL movements that include overhead arm movement

Question 2

Is an ac joint sprain a chronic issue?

Answer 2

NO
happens after a specific event

Question 3

What are some examples of athletes that do overhead movement of arm?

Answer 3

Swimmers, volleyball, waterpolo, throwing sports

Question 4

What are some examples of ADL that may aggravate chronic shoulder pain

Answer 4

Putting on seatbelt
- reaching for something
- grab loop on bus/subway
- getting dressed
- sleeping (hard to find nice position)

Question 5

Define an impingement

Answer 5

Pinching of some kind of anatomic structure/tissue (mechanism, not a name for a single type of injury)

• this leads to pathological tissue breakdown
• tendinopathies and bursitis can be impacted by this

Question 6

How can impingement be categorized?

Answer 6

can happen in 2 categories based on location and mechanics
- sub-acromial impingement (SAI)
- posterior internal impingement (PII)

Question 7

Describe the margins of the sub acromial space

Answer 7

• the coraco-acromial (CA) ligament forms a roof over the space, head of humerus on bottom
• anything in this space will be vulnerable to compression in margins

Question 8

Describe a sub-acromial impingement

Answer 8

• some kind of pinching in sub-acromial space, pinching happens when person is in an overhead position
• when your arm is down the space is optimized
• when we raise arm the space can become really tight, applies pressure to structures within

Question 9

Which structures are most likely to be compromised with a sub-acromial impingement?

Answer 9

1: supraspinatus tendon
2: sub-acromial bursa
3: tendon of long head of bicep

Question 10

Describe the sub-acromial bursa

Answer 10

A little fluid filled sac to help with compression (free synovial pocket of synovial membrane and fluid)

Question 11

Describe the location of the long head of the bicep

Answer 11

Goes inside the joint because it wants to travel to top of glenoid fossa

Question 12

From a mechanical perspective, what is happening to scapular mechanics to cause an SAI?

Answer 12

• not enough ROTATION OF SCAPULA, difficult to raise properly and humerus has to do it
• insufficient POSTERIOR TILT
• excessive ANTERIOR TRANSLATION of humerus (catches anterior margin of sub-acromial space
• reduced acromio-humeral distance (varies in diff ppl, diff acromion features and humerus can slide up)

Question 13

Which impingement is the most common?

Answer 13

SAI

Question 14

In which population do we see a posterior internal impingement?

Answer 14

Athletic population

Question 15

Describe a posterior internal impingement locationally and mechanically

Answer 15

• pinching between the posterior edge of glenoid rim and posterior aspect of the humeral head
• tissues get caught on the inside of the joint rather than superficial structures
  *Sub-acromial structures usually get pinched on the superficial part

Question 16

Pinching happens in very specific positions, which position would PII show up?

Answer 16

Vulnerable position for internal pinching is 90ish degrees abduction and external rotation (think of pitcher)
- get pinxg on posterior side of shoulder

Question 17

Where does pinching happen in a PII?

Answer 17

Between posterior glenoid and humeral head
- usually humerus moves around a lot, which causes it to catch some of the tissues as it spins
- will gather tissues on the back of the shoulder and bring into pinching space

Question 18

What could be caught in a PII?

Answer 18

Infraspinatus (running on posterior glenoid rim)

Supraspinatus (majority of fibres along the top but some posterior fibres can get caught)

Glenoid Labrum (superior part of the posterior aspect - internal structure!) Could have a labral tear

Question 19

An impingement doesn’t tell you what the exact injury is, it tells you _

Answer 19

There is PINCHING happening SOMEWHERE

Question 20

Looking at the mechanical side of PII, what might be happening at the GH/scapula/humerus?

Answer 20

• excessive SCAPULAR PROTRACTION
• excessive cross extension @GH joint
• GIRD (glenohumeral internal rotation deficiency)

Question 21

Describe the excessive cross extension mechanical aspect

Answer 21

• when you throw a ball, the farther you want to throw, the more retraction @scapula you need to have
• if you CAN’T do this, your body will find a diff way
• in an effort to compensate, ppl have a tendency to cross extend through GH joint exclusively rather than @scapula

Question 22

Describe GIRD

Answer 22

• everyone has the capacity to internal/externally rotate to some degree
• lack of internal rotations capacity means GIRD
• we don’t know if lack of internal is the problem or excessive external as a compensation
• GIRD has a 1.5x chance of having a PII issue
• if one group of ppl has 10% less internal rotation, they have 1.5 chance of PII

Question 23

Key IDEA 1: impingement mechanics lead to _

Answer 23

Tissue pathology such as tendinopathy and bursitis

Question 24

Key IDEA 2: there are _ categories of impingement conditions, with different _

Answer 24

2 categories, different impingement positions (SAI and PII)

Question 25

Key IDEA 3: Both categories of impingement involve altered _

Answer 25

Scapular and glenohumeral mechanics