elbow/forearm Flashcards
What are the articulations w/in the elbow and forearm?
Humero-ulnar joint
Humeroradial joint
Proximal radio-ulnar joint
Distal radio-ulnar joint
T/F: olecranon process is on the radius
F: ulna
Fovea of radial head =___, edge of head =___
Concave
Convex
Prox RU joint vs distal RU joint radius and ulna convex vs concave
Prox: convex radial head, concave ulna
Distal: convex ulnar head, concave radius
What restricts radial deviation?
Radial styloid process
What carpal bone is the most injured?
Scaphoid
The humero-ulnar joint is made up of what 2 structures?
Trochlear notch (proximal ulna)
Trochlea (humerus)
The humeroradial joint is made up what 2 structures?
Fovea (proximal radius)
Capitulum (humerus)
T/F: the humeroradial is less congruent compared to humero-ulnar joint
T
What type of joint is the elbow?
Modified hinge (ulna experiences slight ant axial rotation and side-side motion as flex/ext)
Elbow flex and extend near ___ axis of rotation
Medial-lateral
Varus is Latin for
Turned inward (ADD)
Valgus is Latin for
Turned outward (ABD)
T/F: the natural frontal plane angle made by the extended elbow is referred to as normal cubital varus
F: normal cubital valgus
T/F: carrying angle is another term for normal cubital valgus
T
Normal cubitus valgus of the elbow is at an angle of ___ from the longitudinal axis of the humerus
15 degrees
Excessive cubitus valgus is when the forearm is deviated laterally ___
30 degrees
Cubitus varus is when the forearm is deviated medially ___
5 degrees
T/F: women have greater valgus angulation compared to men by about 2 degrees
T
T/F: regardless of gender, valgus angle is larger on the non dominant arm
F: dominant arm
With a valgus force, which side is compressed? Tensed?
Compress= lateral
Tension (stretch)= med
Medial collateral ligament of elbow consists of
Ant, post and transverse fiber bundles
T/F: the posterior fiber bundles of the MCL are the strongest and stiffest
F: ant fiber bundles
T/F: ant and post fiber bundles of MCL provide significant resistance against a valgus (ABD) producing force
T