MSK 2

Question 1

What is chronic osteomyelitis?

Answer 1

• If acute osteomyelitis is not treated it can progress to chronic osteomyelitis- producing permanent damage
• Chronic osteomyelitis can also develop as a complication or pre-existing infection from syphilis
• Multi-organism infections are common with chronic osteomyelitis

Question 2

How does chronic osteomyelitis present?

Answer 2

o	Bone pain
o	Persistent fatigue
o	Pus draining from a sinus
o	Local swelling
o	Skin changes
o	Excessive sweating
o	Chills

Question 3

What are the risks of untreated osteomyelitis?

Answer 3

can spread to other bones  causing widespread infection, sepsis and even death
• With chronic disease- there is destruction of bone, which is permanent and may result in the need for amputation due to poor vascularisation of the remaining bone

Question 4

What is septic arthritis?

Answer 4

Serious infection of the joint space, as it can lead to bone destruction- it is most common in children <2yrs- it usually results from haematogenous spread, but may also occur following a puncture wound or infected skin lesions eg. chicken pox

Question 5

What causes septic arthritis?

Answer 5

Spread from osteomyelitis into joints where the capsule inserts below the epiphyseal growth plate (hip)
• Beyond the neonatal period, the most common organism is Staphylococcus aureus (Hib)
immunodeficiency and sickle cell disease

Question 6

How does septic arthritis present?

Answer 6

Erythematous, warm, acutely tender joint, with a reduced range of movement- in an acutely unwell, febrile child
• Infants often hold the limb still and cry if it is moved- pseudoparesis or pseudoparalysis
Joint effusion in peripheral joints

Question 7

What are the investigations for septic arthritis?

Answer 7

• There is an increased WCC and CRP- blood cultures must be taken
• Ultrasound of deep joints (hip) is helpful to identify an effusion
• X-rays are used to exclude trauma and other bony lesions- however, x-rays are initially normal, apart from wideneing of the joint space and soft tissue swelling
• A bone scan may be helpful and an MRI may demonstrate an adjacent osteomyelitis
• Aspiration of the joint space under ultrasound guidance for organisms and culture is the definitive investigation- ideally, this is performed immediately, unless this would cause a significant delay in giving antibiotics

Question 8

What is the management for septic arthritis?

Answer 8

• A prolonged course of antibiotics is required- initially IV
• Washing out of the joint or surgical drainage may be required if resolution does not occur rapidly or if the joint is deep-seated (hip)
• The joint is initially immobilised in a functional position, but subsequently must be mobilised to prevent permanent deformity

Question 9

What are the unusual organisms which can cause septic arthritis?

Answer 9

• Neonates- Staphylococcus aureus is most common, but E.coli and group B strep also cause disease
• TB- a rare cause of chronic pyogenic arthritis, can affect the spine

Question 10

What are the signs of NAI fractures?

Answer 10

o Ribs- posterior
o Long bones- eg. humerus –especially if not yet mobile
o Multiple fractures
o Complex skull fractures

Question 11

What are the most common locations for fractures in children?

Answer 11

o	Distal foreman- 22.7%
o	Hand, phalanges- 18.9%
o	Carpal-metacarpal- 8.3%
o	Clavicle- 8.1%  immobilise with a sling for 4-6 weeks
o	Ankle- 5.5%

Question 12

What is the management for fractures?

Answer 12

Control haemorrhage, treat pain, prevent limb ischaemia and remove potential sources of contamination- once this has been done the fracture should be reduced and the reduction maintained, these should then be immobilised and splinted before being cast (6wks

Question 13

What is juvenile idiopathic arthritis? (JIA)

Answer 13

a persistent joint swelling (>6 weeks) presenting before 16yrs in the absences of infection or any other defined causes- 95% of children have a disease that is clinically and immunogentically distinct from RA in adults
Affects 1 in 100 children

Question 14

What are the subtypes of JIA?

Answer 14

o Polyarthritis- >4 joints
o Oligoarthritis- up to and including 4 joints
o Systemic- with fever & rashes
o Psoriatic arthritis
o Enthesitis
• Subtyping is further classified according to the presence of rheumatoid factor and HLA B27 tissue type

Question 15

How does JIA present?

Answer 15

Gelling- stiffness after periods of rest
Morning joint stiffness
Pain
intermittent limp or deterioration in behaviour/mood or avoidance of previously enjoyed activities
Joint swelling

Question 16

What are the long term features of uncontrolled JIA?

Answer 16

Bone expansion from overgrowth- which in the knee may cause leg lengthening or valgus deformity, in the hands, discrepancy in digit length, in the wrist, advancement of bone age

Question 17

Which conditions are associated with JIA?

Answer 17

Chronic anterior uveitis- (regular slit lamp screening)
Flexion contractures of the joints- (in most comfortable position)
Growth failure- (leg length discrepancy, micrognathia)
Anaemia of chronic disease
Delayed puberty
Amyloidosis (proteinuria and renal failure)
Osteoporosis (delayed menarche)

Question 18

How is the risk of osteoporosis reduced?

Answer 18

o Dietary supplements of calcium and vitamin D
o Regular weight-bearing exercise
o Minimise oral corticosteroids use
o Bisphosphonates

Question 19

What is the role of MDT in JIA patients?

Answer 19

• There is need for education and support for the child & family, physical therapy to maintain joint function, and links to other specialities including ophthalmology, dentistry and orthopaediac
• The team work closely with school, social services and primary healthcare providers
• The child is encouraged to take part in all activities except contact sports during active flares- with optimal care, most children are managed as outpatients

Question 20

What are the medications used in JIA?

Answer 20

NSAIDs and analgesics
Joint injections (requires sedation or entonox)
Methotrexate (reduces joint damage, nausea)
Systemic corticosteroids (IV methylprednisolone for severe polyarthritis- life- saving for severe systemic arthritis or macrophage activation syndrome
Biologics- anti-TNF alpha, IL-1, CTLA- 4 or IL-6
T-cell depletion coupled with autologous haematopoetic stem cell rescue (bone marrow transplant) is an option for refractory disease

Question 21

What are the outcomes in JIA?

Answer 21

1 in 3 children will have ongoing active disease into adult years, with significant morbidity from previous inflammation
(joint damage requiring joint replacement surgery, visual impairment from uveitits or fractures from osteoporosis)
Psychosocial morbidity