Week 11 Flashcards
What are the three joints of the elbow complex
humero-ulnar
radiohumeral
proximal radio-ulnar
what do proximal and distal radio-ulnar joints allow
supination
normal valgus angles
5-10 degrees males
10-15 degrees females
What reinforces humeroulna joint
collateral ligaments
Which fibres of the medial collateral ligament are strongest
anterior fibres
What function do the posterior fibres of the medial collateral ligament do
they are tensioned by flexion and valgus movements
What tensions the annular ligament
distraction of the radius and external rotation
The medial collateral ligament does what
primary stabiliser against valgus force with wrist flexors and pronators
What is the MOI for MCL of the elbow
excessive valgus force
e.g fall onto outstretched hand (FOOSH)
What does the LCL of the elbow do
primary stabiliser against varus forces
traumatic injury can rupture ligament
What does the interosseous membrane do
binds radius and ulna
-provides mechanism for transmitting force proximally through upper limb
Describe flexion and extension at the elbow
concave surface of the trochlear notch rolls and glides on convex trochlea
- full extension requires : ant dermis, flexor muscles,anterior capsule, MCL anterior fibres
- full flexion requires : posterior capsule elongation, extensor muscles, ulnar nerve, MCL posterior fibres and portions of LCL
flexion and extension at the humeroradial joint
the fovea of the radius rolls and slides over the convex capitulum
Fovea pulled firmly aanst capitulum in active flexion
NOrmal ROM - 5 hypextension to 145 flexion
for patients suffering from inflammation in the elbow, what is the postion of comfort
80 degrees flexion
-volume of air to space in joint is lowest
How might loss of extension occur
long term immobilisation facture inflammation muscle spasticity spinal injury above C5
Normal ROM for pronation and supination
75 degees pro
85 degrees sup
what is required functionally (pronation and supination
100 degree arc
requires approximately 50 degrees each direction