Sternum

Question 1

Sternum is composed of which three parts.

Answer 1

Manubrium, mesosternum (body, corpus stemi) and xiphoid process

Question 2

Sternum forms from…

Answer 2

sternebrae

Question 3

Is the anterior surface of sternum convex or concave?

Answer 3

convex

Question 4

Sternum articulates with…

Answer 4

Clavicle: Clavicular notch

Rib cartilage: Costal notches

Question 5

What are the attachment points of M. sternocleidomastoid?

Answer 5

Manubrium
(also from clavicle) –>to temporal, mastoid process
head rotation and flexion

Question 6

What does sternocleidomastoid do?

Answer 6

head rotation and flexion

Question 7

What are the attachment points of M. sternohyoid?

Answer 7

Manubrium to hyoid

Question 8

What does sternohyoid do?

Answer 8

depression of hyoid

Question 9

Which muscle attache from Manubrium and body - anterior to humerus, proximal?

Answer 9

M. pectoralis major (also from clavicle)

Question 10

What does M. pectoralis major (also from clavicle) do?

Answer 10

adduction, medial rotation and flexion of arm

Question 11

Name four non-metric traits of sternum.

Answer 11

Sternal foramen - (5-10 % of individuals)
Synostosis - Matrical/sclerotic
In ~30% adults the xyphoid has at least one foramen Bifid/Trifid xiphoid process

Question 12

Pectus excavatum and pectus carinarum are what?

Answer 12

developmental anomalies

Question 13

Caused by overgrowth of the costal cartilages which force the sternal plates into a bowed arrangement
Can cause difficulties in breathing. This describes what?

Answer 13

pectus carinarum

Question 14

Failure in fusion of the sternal plates
Associated with other connective tissue disorders including Marfan’s syndrome
Can cause compression of the thoracic viscera depending on severity
More common in males than females (M3:1F). This describes what?

Answer 14

Pectus excavatum