Elbow Disorders Flashcards
What is most common mechanism of injury for a Supracondylar Fracture of the Distal Humerus?
What is a less common mechanim?
For each mechanism, state what patient groups they are more common in?
Falling onto outstretched hand with elbow hyperextended- More common in children< 10, especially boys
Falling onto a flexed elbow- More common in the elderly
Falling onto outstretched hand with elbow hyperextended can lead to Supracondylar Fracture of the Distal Humerus
What are 3 ways this presents in children
- Pain
- Loss of function
- Deformity
Falling onto a flexed elbow can lead to Supracondylar Fracture of the Distal Humerus
What are 3 possible complications
- Malunion-> Cubital Varus (Gunstock deformity)
- Damage to Median (most common), Radial or Ulnar nerve
- Ischaemic contracture (Brachial artery damaged-> Infarction-> Fibrosis-> Fibrous scar contracts
What is the usual cause of Elbow Dislocation
Why?
When a person (often a child) falls on their outstretched hand with elbow partially flexed
During mid-flexion of elbow, stability is reliant more on ligaments (than bone during full flexion/ extension)
What is the most common type of elbow dislocation
Identify 3 features
Posterior
- Posterior displacement of distal fragment (Radius and ulna)
- Torn ulnar collateral ligament
- Fracture and/or ulnar nerve involvement
What is the usual cause of an Anterior Elbow Dislocation?
State 1 feature of this type
Usually due to direct blow to posterior of flexed elbow
- Olecranon fractures (large forced needed for dislocation)
What is Pulled/ nursemaids Elbow?
Most commonly occurs in 2-5 year olds
What are 3 ways it presents in children?
Subluxation (Incomplete dislocation) of radial head
- Reduced elbow movement
- Pain over lateral aspect of proximal forearm
- Parent says “not using their arm”
What are the 3 mechanisms of injury that cause Pulled/ nursemaids Elbow?
- Longitudinal traction applied to arm when pronated
- Falls
- Over reaching for an object
Why is Pulled/ nursemaids Elbow more common during Pronation?
Describe how this happens
During pronation annular ligament is relaxed, so easier for subluxation of radial head to occur
Longitudinal traction on radial head, tears attachment of annular ligament to radial neck. Radial head is displaced distally
What are the commonest types of elbow fractures in adults?
What do they usually result from?
What are 2 ways elbow fractures present?
Radial head fractures
Radial neck fractures
Usually due to a fall on an outstretched hand, when radial head impacts the capitellum of humerus
- Reduced range of motion
- Pain in lateral proximal forearm
How do you see an elbow fracture on an X-ray?
What does this indicate?
Look for a Fat Pad/ Sail sign, which indicates an effusion
effusion could be due to haemarthrosis caused by intra-articular fracture
Why is Elbow Osteoarthritis uncommon
What are 3 patient groups who are more likely to get it
Uncommon because of;
- Well-matched joint surfaces
- Strong stabilising ligaments
- Men
- Manual workers
- Athletes in sports that involve throwing (Baseball, javelin)
What are 5 clinical signs of Osteoarthritis of Elbow
- Crepitus (grating sensation)
- Locking (Due to loose cartilage fragments)
- Late swelling (Due to effusion)
- Parasthesia +/- muscle weakness (Osteophytes impinge on ulnar nerve)
- Elbow stiffness (Usually tolerated well by patient)
What is Rheumatoid arthritis?
Describe it
An autoimmune disease in which autoantibodies (Rheumatoid Factor) attack the synovial membrane.
Inflamed synovial cells proliferate-> Pannus, which penetrates through cartilage and adjacent bone-> Joint erosion and deformity
What are 4 X-ray features of Rheumatoid Arthritis?
- Joint space narrowing
- Periarticular osteopenia
- Subluxation and gross deformity
- Juxta articular bony erosion
