Elbow Joint

Question 1

what two joints associated with elbow?

Answer 1

humeroulnar and humeroradial

Question 2

Humeroulnar

Answer 2

concave ulnar on convex humerus

modified hinge joint

Question 3

humeroradial

Answer 3

concave fovea on radius with convex capitulum, doesn’t touch in extension

radius spins on capitulum during sup./pron.

Question 4

What joint is near elbow?

Answer 4

proximal radioulnar

pivot joint: head of radius and radial notch of ulna

Question 5

Cubital Valgus carrying angle?

Answer 5

10-15 males, 15+ females

excessive varus less than 10 ADD
excessive valgus over 15 ABD

Question 6

What causes ulnar to deviate laterally?

Answer 6

asymmetry of trochlea, medial lip longer

Question 7

What provides stability to joint?

Answer 7

1. joint capsule- weak anteriorly and posteriorly
2. MCL and LCL ligaments
3. articulating surface- olecranon process
4. forearm muscles crossing elbow joint

Question 8

Ulnar collateral ligament (medial)- anterior

Answer 8

medial epicondyle- coronoid

valgus force always taut esp in extension , most important and strongest

Question 9

UCL- posterior

Answer 9

medial epicondyle to olecranon

valgus force in flexion greater than 90

deep to ulnar nerve

Question 10

UCL- transverse

Answer 10

olecranon to coronoid

not much stability

Question 11

Radial Collateral Ligament

Answer 11

2 ligs-

1. RCL- lateral epicondyle- annular ligament
2. LUCL- lateral epicondyle- supinator crest

both prevent varus stress

Question 12

Other ligaments of elbow Joint

Answer 12

Annular and oblique cord

Question 13

Annular

Answer 13

radial notch- radial notch

C- shape like allows for radial head rotation

lined with synovial membrane

Question 14

Oblique Cord

Answer 14

lateral ulnar tuberosity- radius below tuberosity

stabilizes PRU jt during mvmt

prevents inferior translation of radius