Locomotor

Question 1

What types of joint are normally affected in septic arthritis?

Answer 1

Weight bearing joints (knee in >50% cases)

Question 2

What pathogens usually cause septic arthritis?

Answer 2

Blood-borne - S. aureus (80-90%)

Also group B streptococci and H influenzae

Question 3

Clinical features of septic arthritis?

Answer 3

Hot, red, swollen, tender joint
Limited range of movement - very painful
Fever, rigors

neonate will hold limb still - pseudo-paralysis

Question 4

Investigations for septic arthritis?

Answer 4

FBC - WCC
ESR and CRP increased

Joint aspirate –> culture and microscopy
Ultrasound - narrowed intra-articular space, joint effusion, rapid osteoporosis

Question 5

What criteria can be used as a diagnostic tool for septic arthritis?

Answer 5

Kocher criteria - 4/4 = 99% chance, 3/4 = 93% chance, 2/4 = 40%

1. non-weight bearing on affected side
2. Fever
3. ESR > 40mm/hr
4. WCC > 12

Question 6

How does systemic juvenile idiopathic arthritis (JIA) normally present?

Answer 6

Joint symptoms may present late or be overlooked

Child appears ill - remitting fever, variable rash, hepatospenomegaly, anaemia, weight loss and abdo pain

Question 7

How does polyarticular JIA present?

Answer 7

Joint swelling in both large and small joints - usually in a symmetrical pattern
Morning stiffness
Poor weight gain and anaemia may occur

Question 8

Who does pauciarticular JIA tend to affect and how does it present?

Answer 8

Girls <5 yrs

Joint swelling in <5 joints - elbow, knee, hip and ankle

Question 9

What is iridocyclitis and which type of JIA is it most likely to be a complication of?

Answer 9

it is inflammation of the inner eye which can lead to blindness
Pauciarticular JIA can develop this complication

Question 10

management of JIA?

Answer 10

NSAIDS to control inflammation

In severe JIA can use hydroxychloroquine, pencillamine, gold injections and methotrexate injections
In severe systemic disease can use systemic corticosteroids

Physio/occupational therapy used to mobilise joints = daily exercises and night splints

Psychosocial support

Question 11

What is reactive arthritis?

Answer 11

A post infectious transient sero-negative inflammatory joint condition that lasts <6 weeks

–> polyarthritis (particularly large joints and back)
Also: malaise, fatigue, low grade fever, erosions of tongue/soft palate, pustules on the underside of the feet, subungal keratosis (under nails)

Self limiting but can treat with NSAIDS

Question 12

What is reiter’s syndrome?

Answer 12

A sub-type of reactive arthritis:

1. Conjunctivitis
2. Urethritis
3. Arthritis

Question 13

What is DDH and when is it diagnosed?

Answer 13

Developmental dysplasia of the HIP - usually detected at baby checks (midwife and GP)
W/o treatment –> arthritis, hip pain and develop a limp

Can do Barlow test - hip dislocates when hip is adducted and pushed down on
or ortolani test

Question 14

Management of DDH?

Answer 14

<3 weeks - double nappies
3 weeks-6mo = splint hips
6-18mo = Examination under GA + arthogram - surgery (closed reduction)
>18mo = Open reduction

Question 15

What is transient synovitis?

Answer 15

AKA irritable hip - benign condition that typically affects boys between the ages of 2-8 (most common cause of limp in 2-12yrs) –> painful hip on movement –> limp and reduced movement

NB. = afebrile condition but mild UTI may precede hip pain

Question 16

Investigations in transient synovitis?

Answer 16

X-ray - usually normal or increased joint effusion

Bloods - CRP and acute phase reactants are raised

Question 17

Management of transient synovitis?

Answer 17

Self-limiting in few days/week (bed rest)

Analgesia and reassurance

Question 18

Who does slipped capital femoral epiphysis (SCFE) usually affect?

Answer 18

Sedentary teenage boys (10-14) - usually chronic (85%) but an be acute (trauma) - associated with hypothyroidism and hypogonadism

Question 19

What are the sign and treatment for SCFE?

Answer 19

Signs = restricted internal rotation and abduction of the hip
Treatment = surgery (pin in situ)

Complications = perthe’s disease, chondrolysis, recurrence

Question 20

What is perthe’s disease?

Answer 20

Avascualr necrosis of the femoral head (can be a complication of transient synovitis) –> pain in hip and reduced internal rotation
Bilateral in 10-20% cases
Typically affect boys aged 5-10yrs

Question 21

Investigations in perthe’s disease?

Answer 21

X-ray - flattening of femoral head +/- fragmentation

or DEXA scan

Question 22

Management of perthe’s?

Answer 22

<1/2 femoral head = bed rest and skin traction

> 1/2 femoral head = positional (leg in cast) +/- osteotomy