Dislocation

Question 1

Most common shoulder dislocation

Answer 1

anterior inferior (Subcoracoid)

Question 2

What is a Hill-Sachs lesion?

Answer 2

Posterior lateral humerus impaction fracture from anterior shoulder dislocation

Question 3

Soft tissue Bankart lesion

Answer 3

anterior inferior labrum

Question 4

Pt presents with arm sticking straight over the head

Answer 4

Inferior dislocation (luxatio erecta humeri)

Question 5

What % of pts with an inferior dislocation have an associated neurologic injury

Answer 5

60% (usually axillary nerve)

Question 6

Rim sign

Answer 6

no overlap of the glenoid and humeral head (posterior dislocation)

Question 7

Trough sign

Answer 7

reverse Hills Sachs (posterior shoulder dislocation)

Question 8

Signs associated with posterior shoulder dislocation

Answer 8

rim sign trough sign (reverse Hill Sachs) light bulb sign

Question 9

16 yoM s/p fall while playing basketball

Answer 9

Grade IV AC joint separation (Rockwood classification). Complete disruption of the AC and CC ligaments + post displacement of the clavicle into the trap (will see the posterior displacement on axillary view

Question 10

Answer 10

Long head of the biceps dislocation

look for an empty bicipital groove

Question 11

Answer 11

Pertheslesion secondary to Anterior shoulder dislocation

Perthes = Detachment of the anteroinferior labrum (3-6 o’clock) with medially stripped but intact periosteum.

https://radiologyassistant.nl/musculoskeletal/shoulder/instability

Question 12

most common hip dislocation

Answer 12

posterior dislocation

typical in dashboard injuries when the knee hits the dashboard and a force is directed posteriorly