Joint Structures and motions

Question 1

What consists of the Elbow complex?

Answer 1

three bones, three ligaments, two joints, and one capsule.

Question 2

What is the Elbow joint?

Answer 2

articulation of the humerus with the ulna and radius

Question 3

Where does the trcohlea articulate on the humerus?

Answer 3

articulates with trochlear notch of ulna.

Question 4

Where does the capitulum articulate?

Answer 4

head of the radius

Question 5

What type of the joint is the Elbow?

Answer 5

uni-axial hinge joint

Question 6

What’re the two types of movements at the elbow?

Answer 6

flexion

extension

Question 7

How many degrees can be measured for elbow flexion?

Answer 7

145 degrees

Question 8

Why does the elbow not have active hyper-extension?

Answer 8

the motion is blocked by the olecranon process of the ulna fitting into the fossa

Question 9

What is the articulation between the radius and the ulna called?

Answer 9

radio-ulnar joint

Question 10

What happens at the proximal end of the radius?

Answer 10

the radius pivots within the radial notch of the ulna

Question 11

What forms from the pivotal motion of the radius?

Answer 11

superior/proximal radio-ulnar joint.

Question 12

What forms when the distal end of the radius rotates around the ulna ?

Answer 12

the inferior/distal radio-ulnar joint

Question 13

What type of joint is the radio-ulnar joint?

Answer 13

uniaxial pivot joint

Question 14

What happens when pronation/supination occur?

Answer 14

radius moves around the ulna

Question 15

Why does the ulna not rotate?

Answer 15

b/c its locked in by its bony shape at the proximal end

Question 16

What is a carrying angle?

Answer 16

longitudinal axes of humerus and forearm

Question 17

What is the medial side of the humerus called?

Answer 17

trochlea

Question 18

What is the lateral side of the humerus called?

Answer 18

capitulum

Question 19

What are the three distinctively diff. end feels at the elbow?

Answer 19

sot-tissue approx., soft tissue stretch, bony end feel

Question 20

What is an example of soft tissue approximation?

Answer 20

when performing elbow flexion the end feel is soft because the bulk of the arm and forearm compresses together and limits motion

Question 21

What is an example of a bony end feel?

Answer 21

for elbow extension, its hard due to bone-on-bone contact of the olecranon process of the ulna moves into the fossa of the humerus, which limits further motion

Question 22

What is an example of a soft tissue stretch?

Answer 22

during forearm supination the end feel is firm because of ligament tension.

Question 23

What are the distal convex areas of the humerus?

Answer 23

trochlea, which articulates with ulna and capitulum which articulates with radius

Question 24

What are the proximal concave areas of the humerus?

Answer 24

trochlear notch, radial head