Ankylosing Spondylitis

Question 1

What is ankylosing spondylitis

Answer 1

A chronic seronegative spondyloarthropathy which primarily involves the axial skeleton

Question 2

Who is most likely to initially present with ankylosing spondylitis

Answer 2

Men between 20-30

Question 3

What is the genetic association with ankylosing spondylitis

Answer 3

Strong association with HLA B27

Question 4

How do patients with ankylosing spondylitis present

Answer 4

Insidious onset

Morning stiffness

Inflammatory back pain:

• Improves with moderate physical activity
• Starts in sacroiliac joints so may be felt as diffuse buttock pain

Peripheral enthesitis - 1/3 of patients

Peripheral arthritis - 1/3 of patients

Question 5

What do you see on examination of a patient with ankylosing spondylitis

Answer 5

Question mark posture - neck hyperextension and thoracic kyphosis

Progressive loss of all spinal movements - Schober’s test less than 5cm

Tragus to wall distance increased

Extra-articular manifestations

Question 6

What is peripheral enthesitis

Answer 6

Occurs in 1/3 of patients with ankylosing spondylitis

Commonly Achilles tendonitis and plantar fasciitis

Lesions tend to be painful, especially in the morning

May be associated swelling of tendon or ligament insertion

Question 7

What peripheral arthritis occurs in ankylosing spondylitis

Answer 7

Occurs in 1/3 of patients

Usually asymmetrical

Involving:

• Hips
• Shoulder girdle
• Joints of the chest wall (costochondritis)
• Symphisis pubis

Other peripheral joints less often and less severely affected

Question 8

What are the extra-articular manifestations of ankylosing spondylitis

Answer 8

AAAAAAO - 6 As

Eyes - Acute anterior uveitis

Cardiovascular - Aortic regurgitation

Respiratory - Apical fibrosis

Renal - Amyloidosis (v. rare), IgA nephropathy

Neurological - Atlanto-axial subluxation

Metabolic bone disease - Osteoporosis

Question 9

What medication might a patient with ankylosing spondylitis be on

Answer 9

NSAIDs

TNF-alpha inhibitors - if symptoms poorly controlled with NSAIDs (eg. etanercept)

Bisphosphonates - treat osteoporosis

Question 10

What surgery might a patient with ankylosing spondylitis have

Answer 10

To correct spinal deformities

To repair damaged peripheral joints

Question 11

How do you diagnose ankylosing spondylitis

Answer 11

Modified New York Criteria

• Low back pain - for over 3 months, improved by exercise, not relieved by rest
• Limitation of lumbar spine motion
• Limitation of chest expansion relative to normal values for age and sex

Question 12

What is the differential diagnosis for a patient with ankylosing spondylitis

Answer 12

Mechanical back pain

OA

Inflammatory eg. RA