S8) The Elbow

Question 1

What is the elbow joint?

Answer 1

• The elbow is the joint connecting the anatomical arm to the forearm
• It is marked by the olecranon process and the medial and lateral epicondyles

Question 2

Classify the elbow joint in terms of its structure and function

Answer 2

• Structurally, it is classed as a synovial joint
• Functionally, it is classed as a hinge joint

Question 3

Describe the articulating surfaces of the elbow

Answer 3

• Trochlear notch of ulna articulates with the trochlea of humerus
• Head of the radius articulates with the capitulum of humerus

Question 4

Which other joint is also found within the joint capsule of the elbow?

Answer 4

Proximal radioulnar joint

Question 5

Describe the movement of the elbow joint and identify the muscles involved

Answer 5

• Extension: triceps brachii and anconeus
• Flexion: brachialis, biceps brachii, brachioradialis

Question 6

Discuss the stability of elbow joint

Answer 6

• Like all synovial joints, the elbow joint has a strong and fibrous capsule enclosing and strengthening the joint
• The joint capsule is thickened medially and laterally to form collateral ligaments, which stabilise the flexing and extending motion of the arm

Question 7

Describe the anatomical position of the collateral ligaments of the elbow joint

Answer 7

• The radial collateral ligament lies on the laterally, extending from the lateral epicondyle and blending with the annular ligament of the radius
• The ulnar collateral ligament originates from the medial epicondyle, and attaches to the coronoid process and olecranon of the ulna

Question 8

What is a bursa and what does it do?

Answer 8

• A bursa is a membranous sac filled with synovial fluid
• It acts to cushion the moving parts of a joint, preventing degenerative damage and reducing friction

Question 9

Identify the 3 elbow bursa of clinical importance

Answer 9

Question 10

Describe the anatomical location of the 3 elbow bursa

Answer 10

• Intratendinous bursa is located within the tendon of the triceps brachii
• Subtendinous bursa is located between the olecranon and the tendon of the triceps brachii
• Subcutaneous bursa is located between the olecranon and the overlying connective tissue

Question 11

Identify the common injuries to the elbow and wrist joint

Answer 11

• Acute/trauma: fractures, dislocations
• Chronic/degenerative: arthritis, tendinopathies

Question 12

Identify 4 acute / traumatic clinical conditions affecting the elbow

Answer 12

• Elbow dislocation
• Supracondylar fracture
• Radial head/neck fractures
• Radial head subluxation

Question 13

Identify 6 chronic / degenerative clinical conditions affecting the elbow

Answer 13

• Osteoarthritis
• Rheumatoid arthritis
• Lateral elbow tendinopathy
• Medial elbow tendinopathy
• Olecranon bursitis
• Gout tophi

Question 14

What is an elbow dislocation?

Answer 14

• An elbow dislocation is a clinical condition in which the joint surfaces of the elbow are separated and presents with pain, deformity or loss of function
• It is the 2nd most common dislocation and results from FOOSH

Question 15

What is a supracondylar fracture of the distal humerus?

Answer 15

• A supracondylar humerus fracture is a fracture of the distal humerus just above the elbow joint which occurs from FOOSH
• It is usually transverse/oblique above the medial and lateral condyles and epicondyles and involves neurovascular compromise – paraesthesia, radial pulse, capillary return

Question 16

What are radial head/neck fractures?

Answer 16

• Radial head/neck fractures are the commonest elbow fracture and involves a fracture to the proximal radius due to FOOSH
• It presents with lateral pain, modest swelling or loss of range

Question 17

What is radial head subluxation?

Answer 17

• Radial head subluxation (nursemaid’s elbow) is a clinical condition in which the radial head is dislocated from the annular ligament in the elbow joint
• It commonly occurs in young children due to longitudinal traction along extended arm

Question 18

What is elbow osteoarthritis?

Answer 18

• Elbow osteoarthritis is a degenerative disease of the articular cartilage in the elbow joint that can cause pain and stiffness
• It can be primary (degeneration without a cause) or secondary (post-traumatic)

Question 19

What is Rheumatoid arthritis?

Answer 19

• Rhematoid arthritis is a systemic autoimmune disease causing long-term stiffness, swelling and pain in the joints of the body
• Symptoms are due to inflammation of the synovium of small and large joints

Question 20

In terms of swellings around the elbow, what are rheumatoid nodules?

Answer 20

• Rheumatoid nodules are firm, noticeable lumps that form underneath the skin of some rheumatoid arthritis patients
• These lumps generally form on/near the base of the arthritic joints and are the commonest extra-articular manifestation of RA

Question 21

In terms of swellings around the elbow, what is olecranon bursitis?

Answer 21

• Olecranon bursitis (student’s elbow) is the inflammation of the bursa in the elbow joint due to trauma or friction
• It presents with pain, redness and swelling around the elbow and can become infected

Question 22

In terms of swellings around the elbow, what is gout tophi?

Answer 22

• Gout tophi is a disorder of nucleic acid metabolism leading to hyperuricaemia and urate crystal deposits in the joints
• It leads to recurrent attacks of arthritis and mainly affects soft tissues e.g. ear, elbow, achilles tendon

Question 23

What is lateral elbow tendinopathy?

Answer 23

• Lateral elbow tendinopathy (tennis elbow) is a degenerative condition that can cause significant functional impairment in working-age patients
• It is the commonest cause of elbow pain and involves pathology in the common extensor tendon

Question 24

What is medial elbow tendinopathy?

Answer 24

• Medial elbow tendinopathy (golfer’s elbow) is a degenerative condition / overuse injury predominantly seen in athletes
• It is 10x less common than LET and involves pathology in the common flexor tendon