Topic 3: BONES, JOINTS AND MUSCLES OF THE ELBOW REGION Flashcards
Classification of the elbow joint
Synovial, uniaxial, hinge
Movements of the elbow joint
Flexion, extension
- transverse axis (sagittal plane)
Fat pad in the olecranon fossa functions
sits in the fossa to absorb shock when the elbow is extended.
- comes out in extension, in in flexion (check that)
Articular surfaces of the elbow joint
- head of radius - articulates with capitulum of humerus
2. trochlear notch of ulna - articulates with trochlear of humerus
Elbow joint complex
Superior RU joint classification
synovial, uniaxial, pivot (radius pivots around the ulna)
Elbow joint complex
Superior RU joint movements
Pronation & supination
- longitudinal axis (trans plane)
Superior RU joint articular surfaces
- head of radius
2. radial notch of ulna
Elbow and superior RU joints articular capsule
common capsule for elbow and superior RU joint
Elbow and superior RU joints articular capsule attachments
- attaches at articular margins of humerus
- attaches to articular margins of radius
- no direct attachment to ulna
Where is the elbow and superior RU joint articular capsule thickest?
thickest & strongest at sides of joints, relatively weak anteriorly, weak posteriorly
Elbow and superior RU joints synovial membrane
common to both joints
Elbow and superior RU joints extrasynovial fat pads
occupy the fossae where the bony projections do not (absorb shock when elbow = extended)
Elbow and superior RU joints Ligaments
Annular ligament shape
“ring-shaped” or circular
Annular ligament attachments
both attachments on ulna (radial head can spin)
Annular ligament surrounds what>
head of the radius
Annular ligament stops:
ulna moving laterally (prevents breaking of the 2 bones)
because; when annular ligament = put under tension, brings ulna closer into the superior RU jt
Annular ligament movements
allows pronation/ supination
Annular ligament shape/ where is it wider and why?
wider superiorly than inferiorly, funnel shaped –> stops radius from slipping out inferiorly
- follows shape of radial head –> not cone shaped in kids; can easily inferiorly dislocate
Ligaments of the elbow and superior RU joints
- medial/ ulnar collateral ligament
2. lateral/ radial collateral ligament