Upper limb (2) pathologies

Question 1

Describe a supracondylar fracture of distal humerus and its clinical features

Answer 1

90% are seen in children < 10 years, with a peak age of 5-7 years
Cause: falling from a moderate height onto an outstretched hand with elbow hyperextended (eg. child falling off monkey bars)
Presentation: pain, deformity & loss of function
Fracture line is usually extra-articular & distal fragment is usually displaced posteriorly
Complications: 1) malunion, 2) damage to median (most common), radial or ulnar nerve & 3) ischaemic contracture

Question 2

Describe Volkmann’s ischaemic contracture

Answer 2

Complication of supracondylar fracture of distal humerus
Brachial artery damaged/occluded by fracture -> ischaemia of muscles in anterior compartment of forearm -> dead muscle tissue becomes replaced by scar tissue (fibrosis) -> flexion contracture
Wrist is flexed, fingers are extended at MCP joints and flexed at the IP joints
Forearm is often pronated & elbow flexed

Question 3

Describe a dislocated elbow & its clinical features

Answer 3

FOOSH with elbow partially flexed (stability more reliant on the ligaments in mid-flexion)
Most are posterior = distal end of the humerus is driven through joint capsule anteriorly & ulnar CL usually torn
Anterior = direct blow to the posterior aspect of a flexed elbow (olecranon fractures commonly seen -> due to degrees of force required to dislocate the joint)

Question 4

Describe pulled elbow & its clinical features

Answer 4

Subluxation of radial head
Most common in 2-5 years & presentation = reduced movement of elbow & pain over the lateral aspect of proximal forearm
Injury most commonly occurs in pronation = annular ligament is more relaxed (this ligament strengthens with age) – longitudinal traction on the radial head tears the distal attachment of annular ligament -> radial head is displaced distally through the torn ligament

Question 5

Describe radial head and neck fractures & their clinical features

Answer 5

FOOSH when radial head impacts on the capitellum of the humerus
Presentation = pain in lateral aspect of proximal forearm & loss of range of movement
Fracture is difficult to see on x-ray -> ‘fat pad/sail sign’ indicates an effusion is present (likely to be due to a hemarthrosis secondary to an intra-articular fracture)

Question 6

Describe the clinical features of OA of the elbow

Answer 6

Relatively uncommon
Presentation: ‘grating sensation’ or locking in elbow
Swelling occurs relatively late & is due to an effusion
Osteophytes can impinge on the ulnar nerve causing paraesthesia +/- muscle weakness

Question 7

Describe the clinical features of rheumatoid arthritis of the elbow

Answer 7

Autoimmune disease in which autoantibodies attack the synovial membrane
X-ray features = joint space narrowing, periarticular osteopenia, juxta-articular bony erosion, subluxation & gross deformity
Management = usually medically rather than surgically

Question 8

Describe the clinical features of lateral elbow tendinopathy (‘tennis elbow’)

Answer 8

Presentation: pain at the site of the common extensor origin at the lateral epicondyle
Extensor carpi radialis brevis is weakened from overuse -> microscopic tears form in the tendon where it attaches to the lateral epicondyle
Leads to inflammation & pain
Management: modification of activities, physiotherapy, bracing & rarely, injections or surgery

Question 9

Describe the clinical features of medial elbow tendinopathy (‘golfers’ elbow’)

Answer 9

Presentation: aching pain over medial elbow & pain produced on resisted flexion/pronation of wrist
20% suffer from ulnar nerve symptoms = proximity of the ulnar nerve to the medial epicondyle
Treatment similar to LET

Question 10

List three common causes of swelling around the elbow

Answer 10

Olecranon bursitis
Rheumatoid nodules
Gouty tophi

Question 11

Describe olecranon bursitis (‘student’s elbow’)

Answer 11

Inflammation of the olecranon bursa
Caused by repeated minor trauma
Presentation = due to cosmetic concern of the unsightly swelling
Treatment = compression bandaging +/- aspiration

Question 12

Describe rheumatoid nodules

Answer 12

Commonest extra-articular manifestation of RA ~20% patients with RA (tend to be smokers & more aggressive joint disease)
Occur over exposed regions that are subject to repeated minor trauma
Presentation = cosmetic concerns
Treatment = improving medical control of the underlying rheumatoid disease

Question 13

Describe gouty tophi

Answer 13

Tophi = nodular masses of monosodium urate crystals deposited in soft tissues
Late complication of hyperuricaemia & develop in > 50% of patients with untreated gout
Painless, but complications can include pain, soft tissue damage & deformity, joint destruction & nerve compression