Chapter 77 - Disorders of the Sternoclavicular Joint

Question 1

what are the primary stabilizers of the SC joint?

Answer 1

anterior and posterior ligaments
specifically the posterior ligament (twice as thick and twice as strong as the anterior ligament)

Question 2

intraarticular disc ligament

Answer 2

acts as a checkrrein to medial displacement of the clavicle

Question 3

medial clavicular epiphysis ossification and fuse

Answer 3

last to ossify - starts at like 18 yo
doesnt close until 25 yo

Question 4

what is more common, anterior or posterior SC dislocations?

Answer 4

Anterior

posterior dislocations may be associated with mediastinal injury in up to 25%

Question 5

pathoanatomy for posterior dislocation

Answer 5

posteriorly directed force to medial clavicle

force to the posterolateral shoulder with the arm internally rotated

Question 6

pathoanatomy for an anterior dislocation

Answer 6

force to the anterolateral shoulder with external rotation of the shoulder

Question 7

considerations for skeletally immature people?

Answer 7

will usually cause a medial clavicle physeal injury not a sc dislocation

Question 8

which dislocations are more likely to stay reduced?

Answer 8

posterior > anterior

Question 9

causative bacteria for SC septic arthritis?

Answer 9

staph, strep, n. gonorrhea

IVDA: pseudomonas, candida

Question 10

what fixation method is contraindicated in fixing SC dislocations?

Answer 10

pins/wires - can migrate to mediastinum