Common Elbow Conditions Flashcards
What does the capitulum articulate with?
Radius
What does the trochlea articulate with?
Ulna
Which bone moves in pronation and supination?
Radius rotates around the fixed ulna
In a normal elbow joint, if you draw a line down the anterior surface of the humerus and the middle of the radius where should the lines cross?
The capitulum
What type of membrane surrounds the joint capsule of the elbow?
Synovial membrane
What are the 3 ligaments of the elbow joint?
Radial collateral ligament
Ulnar collateral ligament
Annular ligament
What is the function of the Radial collateral ligament?
Resists force applied from the medial side
What is the function of the ulnar collateral ligament?
Resists force applied from the lateral side
What is the function of the Annular ligament?
Holds head of the radius in place
What are the general presentations of an elbow condition?
Pain
Swelling
Restriction of movement
Deformity
Where does the fracture usually take place in a supracondylar fracture?
Fracture line extra articular so doesn’t involve the joint
Above the condyles
In a supracondylar fracture, what direction is the distal fragment usually displaced?
Posteriorly
What sort of trauma leads to a supracondylar fracture?
Fall onto an outstretched hand (FOOSH) with arm normally EXTENDED
What nerves and blood vessels are at risk of damage from a supracondylar fracture?
Median nerve
Radial nerve
Brachial artery
What can happen as a result of a supracondylar fracture damaging the brachial artery?
Oedema (Compartment syndrome)
Ischaemia
Muscle infarction leading to Volkmann’s Ischaemic contracture
How does muscle infarction lead to Volkmann’s Ischaemic contracture?
Dead muscle tissue undergoes repair
Scar tissue replaces dead tissue via fibrosis
Myofibroblasts in fibrotic tissue contract
What branch of the median nerve is most at risk with a supracondylar fracture?
Anterior interosseous branch
How can injury to the brachial artery be assessed?
Detect capillary re-fill time, press on the nails and see how long it takes for them to go from white back to pink
What nerve is likely damaged if the patient cant make an OK sign with their fingers properly?
Anterior interosseous branch of median nerve
What the possible ways a supracondylar fracture can be managed?
Closed reduction and held in position with a plaster
Closed reduction and percutaneous pinning
What is a pulled elbow?
Subluxation of the radial head from the annular ligament
What is subluxation?
Partial dislocation of a joint with some abnormal apposition of the articulating surfaces
Why is subluxation of the radial head/pulled elbow common in children?
Annular ligament is weaker in children
How is subluxation of the radial head/pulled elbow normally caused?
Longitudinal traction with arm extended and forearm pronated
(Swinging a child around in circles)
How is a pulled elbow/subluxation of the radial head treated?
Flex the elbow and supinate (REVERSE THE FORCES THAT CAUSED)
How are elbow dislocations usually caused?
Fall Onto Outs Stretched Hand (FOOSH) So arm in extension
What way is the elbow normally dislocated in a fall onto an outstretched hand?
Posterior and Lateral (Posterolateral)
Why are elbow dislocations more common when the joint is partially flexed?
Here elbow stability relies more on the ligaments
When fully extended or flexed the bone configurations contribute to stability the most
What may be damaged as a result of an elbow dislocation?
Ulnar nerve
Ulnar collateral ligament
How are dislocations described in terms of direction?
Depends on the displacement of the distal fragment
So in an elbow dislocation the ulna and radius normally have moved posterior and laterally
How do you treat an elbow dislocation when theres no associated neurovascular damage?
Analgesics then reduce back into place