elbow chapter 14 Flashcards
define what joint is the humeroulnar joint
Hinge joint
ROM: 0°-145°
Loose-Pack Position
70° flexion, 10° supination
when is the humeroulnar joint a closed pack
extension
what type of axial of the humerolnar joint
Diarthrodial
Uniaxial
1° freedom
√ and / in sagittal plane
define the humeroradial closed and open pack
Loose Pack Position
Opposite humeroulnar joint
Full Extension & supination
Closed pack position
90° √, 5° forearm supination
define the inferior radialulnar joint closed/open pack
Loose Pack
10 º supination
Closed Pack
5 º supination
the motions of the radioulnar joint
Forearm motions
~90° supination
~80° pronation
what are the ROM of the joints
Uniaxial joint
A. flexion √ ~145°
B. extension / 0°
Active hyper extension blocked by the olecranon process
what is the relationship of ulna and radius in extension
The radius and ulna are not in line with the humerus on extension
Hand is on outside of imaginary line
when is the hand in the inside
in flexion, the hand is on the inside
Functionally better
Getting hand to mouth
define the joint capsule
Humeroulnar, humeroradial, and superior radioulnar joints all within
Strengthened by annular ligament and collateral ligament
define the medial or ulnar collateral ligament
Triangular shaped
Medial stability
Medial epicondyle to coronoid and olecranon process of ulna
define the lateral or radial collateral ligament
Triangular shaped
Lateral stability
Lateral epicondyle to annular ligament and lateral ulna
define the annular ligament
Encompasses radial head
Holds it against ulna
Attaches anteriorly & posteriorly to radial notch of the ulna
interosseous membrane function
Keeps radius and ulna together
Serves as a muscle attachment
Radioulnar articulations held together by
Annular ligament
Interosseous membrane