Shoulder Dislocation and Instability

Question 1

95% of the shoulder dislocations/instability occur in what direction?

Answer 1

anterior

Question 2

What are the 3 most typical MOIs for an anterior dislocation?

Answer 2

• blow to the abducted, externally rotated, and extended arm (blocking a basketball shot)
• blow to the posterior humerus
• fall on an outstretched and abducted arm

Question 3

Patients with an anterior dislocation typical complain of pain and a feeling of instability when the arm is in what position?

Answer 3

abducted and externally rotated

Question 4

What are the 3 most typical MOIs for a posterior dislocation?

Answer 4

• falls from height
• violent muscle contraction due to epileptic seizures or electric shocks
• blow to the anterior shoulder

Question 5

What are the 2 most typical MOIs for an inferior dislocation?

Answer 5

• axial loading with the arm fully abducted or forceful hyperabduction of the arm
• during a fall and suddenly grasping onto an object above their head resulting in hyperabduction

Question 6

What can traumatic shoulder dislocation lead to?

Answer 6

instability

Question 7

What is the rate of repeated dislocation directly related to?

Answer 7

patient’s age

Question 8

What other injury is found in 90% of young active patients with traumatic shoulder dislocation?

Answer 8

labral injuries often described as Bankart lesions when the anterior inferior labrum is torn

Question 9

What are the associated injuries in older patents (55+)?

Answer 9

rotator cuff tears or fractures

Question 10

What are atraumatic shoulder dislocations usually caused by?

Answer 10

intrinsic ligament laxity or repetitive microtrauma leading to joint instability

Question 11

In what patient populations are atraumatic shoulder dislocation common?

Answer 11

in overhead and throwing sports, such as swimmers, gymnasts, and pitchers

Question 12

In what position do patients following shoulder dislocation hold their arm?

Answer 12

in an externally rotated position

Question 13

What typically improves pain and deformity?

Answer 13

manual relocation

Question 14

Why are posterior dislocation often missed?

Answer 14

because the patient usually holds the shoulder and arm in an internally rotated position, which makes the shoulder deformity less obvious

Question 15

What do posterior dislocation patients complain of not being able to do functionally?

Answer 15

push open a door

Question 16

What are 3 stability tests that can be performed to help diagnose?

Answer 16

• apprehension test
• load and shift test
• O’Brien’s test

Question 17

What are the 3 standard radiographic views?

Answer 17

• AP
• axillary
• orthogonal

Question 18

Why are orthogonal views used?

Answer 18

to identify a posterior shoulder dislocation, which can be missed easily with the AP view of the shoulder

Question 19

What type of fracture is associated with an anterior shoulder dislocation?

Answer 19

indented compression fractures at the posterior-superior part of the humeral head

Question 20

What are 2 other imaging techniques that can help identify labral and ligamentous involvement?

Answer 20

• MRI

- MRI anthrogram

Question 21

Hill Sachs lesions occur in __-__% of anterior dislocations

Answer 21

35-40

Question 22

When do Bankart lesions form?

Answer 22

when the glenoid is disrupted with dislocation

Question 23

What is the recommended treatment for acute dislocations?

Answer 23

reduction ASAP

Question 24

What are the 2 types of reduction maneuvers?

Answer 24

• Stimson procedure

- Traction Countertraction procedure

Question 25

Following reduction of an acute dislocation what is the rehab protocol?

Answer 25

• sling immobilization for 2–4 weeks along with pendulum exercises
• early physical therapy

Question 26

If a “TUB” is the clinical diagnosis surgery is often required. What does TUB stand for?

Answer 26

Traumatic incident
Unilateral shoulder dislocation
Bankart lesion

Question 27

What is the rehab protocol for atraumatic chronic shoulder instability?

Answer 27

Physical therapy and a regular maintenance program, consisting of scapular stabilization and postural and rotator cuff strengthening exercises

Question 28

If an “AMBRI” is the clinical diagnosis surgery is often not required. What does AMBRI stand for?

Answer 28

Atraumatic
Multidirectional
Bilateral instability
Rehabilitation is the mainstay for treatment
Inferior capsular shift surgery is rarely required

Question 29

When should you refer?

Answer 29

• Patients who are at risk for second dislocation, such as young patients, certain jobholders (eg, police officers, fire fighters, and rock climbers) to avoid recurrent dislocation or dislocation while at work.
• Patients who have not responded to conservative approach or who have chronic instability.