Joint Structures and motions Flashcards
What consists of the Elbow complex?
three bones, three ligaments, two joints, and one capsule.
What is the Elbow joint?
articulation of the humerus with the ulna and radius
Where does the trcohlea articulate on the humerus?
articulates with trochlear notch of ulna.
Where does the capitulum articulate?
head of the radius
What type of the joint is the Elbow?
uni-axial hinge joint
What’re the two types of movements at the elbow?
flexion
extension
How many degrees can be measured for elbow flexion?
145 degrees
Why does the elbow not have active hyper-extension?
the motion is blocked by the olecranon process of the ulna fitting into the fossa
What is the articulation between the radius and the ulna called?
radio-ulnar joint
What happens at the proximal end of the radius?
the radius pivots within the radial notch of the ulna
What forms from the pivotal motion of the radius?
superior/proximal radio-ulnar joint.
What forms when the distal end of the radius rotates around the ulna ?
the inferior/distal radio-ulnar joint
What type of joint is the radio-ulnar joint?
uniaxial pivot joint
What happens when pronation/supination occur?
radius moves around the ulna
Why does the ulna not rotate?
b/c its locked in by its bony shape at the proximal end
What is a carrying angle?
longitudinal axes of humerus and forearm
What is the medial side of the humerus called?
trochlea
What is the lateral side of the humerus called?
capitulum
What are the three distinctively diff. end feels at the elbow?
sot-tissue approx., soft tissue stretch, bony end feel
What is an example of soft tissue approximation?
when performing elbow flexion the end feel is soft because the bulk of the arm and forearm compresses together and limits motion
What is an example of a bony end feel?
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
What is an example of a soft tissue stretch?
during forearm supination the end feel is firm because of ligament tension.
What are the distal convex areas of the humerus?
trochlea, which articulates with ulna and capitulum which articulates with radius
What are the proximal concave areas of the humerus?
trochlear notch, radial head
