Elbow Disorders (Session 8) Flashcards
How might someone acquire a supracondylar fracture of the distal humerus?
1-Falling from moderate height w./ elbow hyperextended (e.g. child falling off monkey bars) 2- Falling on flexed elbow
In what age groups are supracondylar fractures most common?
Children <10yrs (more common in boys)
How may a child who has suffered a supracondylar fracture of the distal humerus present?
Pain, deformity, loss of function
In which direction is the distal fragment usually displaced?
Posteriorly
What are the 3 main complications following a supracondylar fracture of the distal humerus?
1, Malunion- results in cubits varus (gunstock deformity)
2, Damage to median/radial/ulnar nerve
3, Ischaemic contracture
What is an Ischaemic contracture? i.e. How does it come about if a patient has suffered a supracondylar fracture of the distal humerus?
- Brachial artery damaged/occluded by displaced fracture-
- reflex spasm of collateral circulation
- ischaemia in anterior compartment of forearm
- oedema + rise in pressure- compartment syndrome
- dead muscle tissue- replaced- scar tissue
- flexion contracture- Volkmann’s ischaemic contracture
How can Volkmann’s ischaemic contracture be characterised?
- Wrist=flexed
- Fingers=extended at metacarpophalangeal joints
- Forearm pronated
- Elbow flexed
What measures can be taken to minimise the risk of complications following a suprachondylar fracture of the distal humerus?
Prompt examination- neurovascular system- if compromise to supply- emergency reduction and fixation of fracture
Explain the common mechanism for elbow dislocation?
FOOSH with elbow partially flexed
Why is a dislocation of the elbow more likely if the elbow is is in mid-flexion?
Configuration of elbow mean that:
- Bone most stable in full extension and flexion
- Stabilty in mid-flexion=more reliant on ligaments
Which joint is the most common to dislocate in children?
Elbow
(2nd most common in adults)
What % of elbow dislocations do sports injuries account for?
50%
What % of elbow dislocations are posterior?
90%
Which way do the bones at the elbow joint move in a posterior dislocation?
- Distal end of humerus- driven through joint capsule anteriorly
- Ulnar collateral ligament (usually torn)
- (Often) Fracture/ulnar nerve involvement
What’s the usual mechanism for anterior dislocations (<10% of anterior dislocations)?
Direct blow to posterior aspect of flexed elbow
Remember: displacement of distal fragments (ulnar and radius) in the type of dialocation (anterior/posterior)
What fracture is commonly associated with an anterior dislocation of the elbow (due to the force required)?
Olecranon fracture
What’s another name for a ‘pulled elbow’?
‘nursemaids elbow’
What has occured if a patient has a ‘pulled elbow’?
Subluxation of radial head
(Subluxation= partial disruption of joint with some remaining but ABNORMAL opposition of articular surfaces = incomplete dislocation)
In which age group does a ‘pulled elbow’ most commonly occur?
Children age 2-5
How will a child with a pulled elbow present?
- Reduced movement of elbow
- Pain over lateral aspect of proximal forearm
What are the mechanisms of injury for a pulled elbow?
- Longitudinal traction applied to arm with forearm pronated (eg swinging child by their arms) (50%)
- Falls
- Over-reaching for an object
Why does a pulled elbow more commonly occur when the forearm is pronated?
- Annular ligament taut in supination
- Annular ligament more relaxed in pronation
Logitudinal traction on radial head- tears annular ligament from radius
Radial head displaced distally through torn ligament
Why does a ‘pulled elbow’ injury become less common as the child ages?
Annular ligament natural strengthens
Radial head and neck fractures are the commonest type of elbow fracture.
What is their usual mechanism of injury?
FOOSH
If a patient has a radial head or neck fracture, how do they present?
- Pain in lateral aspect of proximal forearm
- Loss of range of movement
- Swelling (relatively modest)
What is the ‘sail sign’?
- Due to displacement of anterior fat pad
- Indicates effusion
- Likely due to haemarthrosis secondary to intra-articular fracture
- Appears black on x-ray
(can also be on the posterior surface)
Why is osteoarthritis of the elbow relatively uncommon?
- Well-matched joint surfaces
- Strong stabilising ligaments
In which population is OA of the elbow more common?
- More commonly men than women (4:1 ratio)
- Manual workers
- Athletes
If a patient has OA in their elbow- how wil they present?
- Crepitus
- Locking (due to loose fragements of cartilage)
- Paresthesia (due to compression of the ulnar nerve by osteophytes)
What is rheumatoid arthritis?
- Autoimmune disease
- Autoantibodies- rheumatoid factor- attack synovial membrane
- Inflamed synovial cells- proliferate- form PANNUS
- (Pannus=abnormal layer of fibrovascular tissue or granulation tissue)
- PANNUS- penetrates through cartilage and bone- causing erosion and deformity
Which joints are most commonly affected by rheumatoid arthritis?
- MCPJs- Hands and feet
- PIPJs- Hands and feet
- Cervical spine
What other complications can be caused by rheumatoid arthritis?
- Damage to:
- Eyes
- Skin
- Lungs
- Heart
- Blood vessels
- Kidney
- Anaemia of chronic disease
What % of the population is affected by osteoarthritis?
1%
(Peak onset= 40-50yrs)
(Women more commonly affected 2:1)
What are the x-ray features of rheumatoid arthritis? (LESS)
- Loss of joint space
- Erosion (of not cartilage protected bone)
- Soft tissue swelling
- Subluxation and deformity
How is rheumatoid arthiritis managed?
- Disease modifying medication
- if severe Surgery required
What is another name for Lateral elbow tendinopathy?
Tennis elbow
What is tendinopathy?
Chronic overuse of tendons
What is the prevalence of lateral elbow tendinopathy?
3% in 40-60 years
In tennis elbow the tendon of which muscle is affected?
Common extensor tendon at lateral epicondyle
of Extensor carpi radialis brevis
(Weakened in overuse, microscopic tears form where is attaches)
What does the extensor carpi radialis brevis stabilise when the elbow is straight?
The wrist
Apart from tennis players, who else is at is prone to acquiring ‘tennis elbow’?
Painters, plumbers, carpenters
How is ‘tennis elbow’ managed?
- Activity modification- give tendon oppourtunity to heal
- Physiotherapy
- Bracing
- Injections/surgery
Disorder=usually self limiting –>90% patients recover within 1year
What is another name for medial elbow tendinopathy (MET)?
Golfer’s elbow
What part of the arm/forearm is affected by Medial elbow tendinopathy?
Common flexor origin at medial epicondyle
How common is Medial elbow tendinopathy compared to Lateral elbow tendiopathy?
MET= 10x less likely that LET
Apart from golfer’s, who else might suffer from MET?
Bowlers, archers, weightlifters
Where is the most common site of pathology for Medial elbow tendinopathy?
Interface between pronator teres and flexor carpi radialis
When and where will a patient experience pain with Medial elbow tendinopathy?
- Over medial elbow
- Pain produced:
- Resisted flexion
- Pronation of wrist
Ulnar nerve symptoms present in 20% cases
How is Medial elbow tendinopathy treated?
Same as LET
What does the cubital tunnel allow passage for?
(Behind medial epicondyle of humerus)
Ulnar nerve
The ulnar nerve passes under a tendinous arch to enter the cubital tunnel which is made up of the two heads of which muscle?
Flexor carpi unaris
What is cubital tunnel syndrome?
Compression of ulnar nerve in cubital tunnel
Where is the parasthesia felt in cubital tunnel syndrome?
Cutaneous territory of ulnar nerve
How can the cubital tunnel syndrome be treated?
Decompress nerve
Surgical release and transposition anterior to medial epicondyle
What are 3 common causes of swellings around the elbow?
- Olecranon bursitis
- Rheumatoid nodules
- Gouty tophi
What is olecranon bursitis?
Inflammation of olecranon bursa
What may cause olecranon bursitis?
Repeated minor trauma
(STUDENT’S ELBOW)
-Contents- filled with serous fluid
How does a patient with olecranon bursitis present?
- Swelling= soft , cystic, transilluminates
- Cosmetic concern
How is olecranon bursitis treated?
Conservatively:
- Compression- bandage
- Aspiration
- Hydrocortisone injection if chronic
- Antibiotics (if due to infection)(may require Surgical drainage)
What is the most common extra-articular manifestation of rheumatoid arthritis?
(affects 20% of those w./ rheumatoid arthritis)
Rheumatoid nodules
(tend to be smokers+ have more aggressive joint disease)
Where do rheumatoid nodules appear?
Over exposed regions- subject to repeated minor trauma
Other than the elbow, where else can rheumatoid nodules affect?
FIngers, forearms, back of heel
How are ‘rheumatoid nodules’ treated?
Improving medical control of underlying rheumatoid arthritis
What is gout?
- Inflammatory condition
- Defective purine metabolism
- Increased production of uric acid
- Urate crystals form in:
- Synovial cavity of joints
- in Tendons
- in Surrounding tissues
- Urate crystals trigger Acute inflammation
How should gout be treated?
- Anti-inflammatory drugs in acute phase
- Xanthine oxidase inhibitors eg allopurinol- reduces production of uric acid
What does gout increase the risk of?
Long-term secondary osteoarthritis due to damage to articular cartilage
What are Gouty tophi?
Nodular masses of urate crystals deposited in soft tissues
What causes gouty tophi?
- Late complication of hyperurocaemia
- Untreated gout
What are some complications of Gouty tophi?
Pain
Soft tissue damage
Deformity
Joint destruction
Nerve compression
Where are Gouty tophi usually found?
Fingers
Ears
Olecranon bursa
Subcutaneous tissue of elbow
What is Froment’s sign?
Test for ulnar nerve palsy:
Paralysis of adductor pollicis
Why is injury to the musculocutaneous nerve uncommon?
Well protected by axilla
How might the musculocutaneous nerve become damaged?
- Stabbing
- Anterior dislocation of shoulder
- Shoulder surgery
What functions will be affected if the musculocutaneous nerve is damaged?
- Coracobrachialis
- Biceps brachii
-
Brachialis
- =paralysed
Motor Functions
Flexion at shoulder and elbow= weakened
(remain possible due to pectoralis major and brachioradialis)
Supination= weakened
Sensory Functions
Loss of sensation- over radial (lateral side) of forearm
