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Flashcards in Shoulder Deck (22):
1

What is the primary function of the scapula?

Keep glenoid fossa and acromion in proper position during movement of humerus

2

Subscapularis
What does it do?
Where does it attach?

Internal rotation. Also depresses / centers humeral head in glenoid as deltoid abducts the arm.
Attaches to lesser tuberosity

3

What is the most commonly injured rotator cuff muscle?

Subscapularis

4

Infraspinatus / teres minor
What doe they do?
Where do they attach?

External rotation
Attach to greater tuberosity

5

What does supraspinatus do?

Abduction in plane of scapula (scaption)

6

Shoulder separation
Which joint?
Cause
Epidemiology
Treatment

•AC joint sprain
•Usually caused by a direct fall on the lateral shoulder.
•5x more common in males. Usually 3rd decade.
•Type I / II don’t need surgery. Use sling, ice, pain meds, and rehab.
•III is controversial. IV-VI often require surgery.

7

Gender distribution for GH dislocation

3x more common in males

8

Mechanism of GH dislocation

Forced external rotation and abduction.

9

What nerve is commonly damaged w/ GH dislocation? What does it innervate?

Axillary nerve innervates deltoid

10

Bankart lesion

Damage to anterior / inferior labrum, which provides lots of stability, so damage → high rate of recurrence

11

Hill-Sachs lesion

Indentation of humeral head caused by impaction of posterior superior humeral head on anterior inferior glenoid as it pops out of the socket. Also cause high rate of recurrence.

12

What causes a posterior GH dislocation?

Trauma, electrical shock, or seizure

13

Position of arm after posterior GH dislocation

Adducted and internally rotated

14

How is posterior GH dislocation diagnosed?

Axillary X ray

15

Treating GH dislocations

•Reduce dislocation after careful neurologic exam. Do post-reduction x rays to evaluate for fractures.
•Sling / PT
•Follow-up exam 3-10 days after dislocation. Include neurovascular exam, ROM, strength, and stability tests.
•PT is mainstay for chronic instability. Surgery if this fails.
•Pxs w/ Bankart lesions should have surgery right away due to 90% chance of repeat dislocations w/o surgery.

16

What 2 things may subacromial bursitis cause?

Impingement or RC dysfunction

17

Causes of impingement syndrome (7)

Overuse, aging, hypermobility, acromial hooking, spurring, calcification of coracoacromial ligament, supraspinatus dysfunction (humeral head rises w/ abduction).

18

3 intrinsic causes of RC tendonopathy

Poor microvascular blood supply, apoptosis, tissue overload / overuse

19

2 extrinsic causes of RC tendonopathy

External compression of cuff and scapular dyskinesis

20

Treating impingement and RC tendonopathy in young vs old.

•Address causative factors:
•Younger population – instability, muscle weakness or flexibility, overuse, capsular or muscle imbalance
•Older population –impingement secondary to bone spurs or degenerative tendon
•Use PT first for both populations

21

Treating RC tears

•Surgery for young / active pxs or acute large tears
•Non-operative for chronic or partial tear. Includes PT and steroid injections.
•Not all are fixed b/c often don’t cause problems. Partial / full thickness tears are found in half of asymptomatic 50 year olds and 80% of asymptomatic 80 year olds.

22

What x ray views are used for shoulder dislocations?

Scapular Y view or axillary view