High-yield

Question 1

Limp ddx

Answer 1

• developmental dysplasia of the hip
• perthes disease
• transient arthritis/synovitis
• septic arthritis
• slipped upper femoral epiphysis (SUFE)

Question 2

DDH

Answer 2

femoral head does not sit fully in the acetabulum → easily dislocated

Question 3

DDH risk factors

Answer 3

• first born child
• breech presentation
• females
• fmhx of ddh
• oligohydramnios
• birth weight > 5kg
• congenital calcaneovalgus foot deformity

Question 4

DDH screening

Answer 4

• following infants require a routine USS:
  
  • first-degree fhx of hip problems in early life
  • breech presentation at/after 36 weeks gestation
  • multiple pregnancy
• all infants screened at both the newborn check & six-week baby check using the Barlow and Ortolani tests

Question 5

DDH signs

Answer 5

• painless limp
• delayed walking
• affected leg is shorter → due to atrophy of hip muscles
• more skin folds on affected leg

Question 6

DDH ix

Answer 6

• NIPE → barlow (dislocate) & ortolani (relocate)
• USS of hip (gold standard)
• x-rays → 1st line if child > 4.5 months

Question 7

DDH mx

Answer 7

• most unstable hips spontaneously stabilise by 3-6 weeks of age
• younger kids → Pavlik harness (before 6 months)
• older kids → combined femoral & pelvic osteotomies

Question 8

Perthes disease

Answer 8

avascular necrosis of the femoral head → flattened & fragmented femoral head is unable to rotate smoothly in acetabulum → restricts mobility

Question 9

Perthes disease clinical features

Answer 9

• presents in primary school kids, 5x more common in boys
• hip pain - develops progressively over a few weeks
• limp
• stiffness & reduced range of movement

Question 10

Perthes disease ix

Answer 10

• hip x-ray → increased density in femoral epiphysis
• technetium bone scan/MRI if normal x-ray and symptoms persist

Question 11

Perthes disease mx

Answer 11

• <6 years - observation, analgesia & bracing
• > 6 years - surgical repair

Question 12

Perthes disease complications

Answer 12

• osteoarthritis
• premature fusion of growth plates

Question 13

Transient synovitis

Answer 13

• inflammation of the synovium
• acute hip pain following a recent viral infection & typical age group is 3-8 years

Question 14

Transient synovitis clinical features

Answer 14

• acute limp/refusal to weight bear
• mild/no fever
• pain on exercise, comfortable at rest
• limited internal rotation

Question 15

Transient synovitis ix

Answer 15

Diagnosis of exclusion
- blood cultures
- USS-guided joint aspiration
- hip x-ray

Question 16

Transient synovitis mx

Answer 16

• rest
• analgesia - NSAIDs

Question 17

Septic arthritis risk factors

Answer 17

• osteomyelitis
• sickle cell anaemia
• diabetes/immunocompromised

Question 18

Septic arthritis clinical features

Answer 18

• acute painful joint → unable to weight bear
• pain at rest, worse on movement
• high fever
• unilateral swollen red knee/thigh leg held in flexed, abducted & externally rotated position
• tenderness over head of femur

Question 19

Septic arthritis ix

Answer 19

• USS-guided joint aspirate
• blood cultures

Question 20

Septic arthritis mx

Answer 20

• joint aspiration
• IV flucloxacillin for 4-6 weeks (IV clindamycin in pen allergic)
• child with limp/hip pain & fever = same day assessment

Question 21

SUFE risk factors

Answer 21

• secondary school boys (10-15)
• overweight

Question 22

SUFE clinical features

Answer 22

• initially presents with stiff hip
• loss of internal rotation of the leg in flexion
• hip pain radiates to knee/thigh presents with externally rotated hip & antalgic gait

Question 23

SUFE ix

Answer 23

AP & lateral (typically frog-leg) x-ray views

Question 24

SUFE mx

Answer 24

• bed rest and crutches
• orthopaedics referral & internal fixation (single cannulated-screw placed in the centre of the epiphysis)

Question 25

SUFE complications

Answer 25

- osteoarthritis - avascular necrosis of the femoral head - chondrolysis - leg length discrepancy

Question 26

HSP

Answer 26

IgA vasculitis that presents with a purpuric rash affecting the lower limbs and buttocks in children Inflammation occurs in the affected organs due to IgA deposits in the blood vessels

Question 27

HSP clinical features

Answer 27

1) purpura - rash caused by inflammation and leaking of blood from small blood vessels under the skin, forming purpura - typically start on the legs & spread to the buttocks 2) joint pain - mostly affecting the knees and ankles 3) abdominal pain - can lead to gastrointestinal haemorrhage, intussusception & bowel infarction 4) renal involvement - can cause IgA nephritis

Question 28

HSP ix

Answer 28

- FBC & blood film - renal profile - serum albumin - CRP - blood cultures - urine dipstick - urine protein:creatinine ratio - blood pressure

Question 29

HSP diagnosis

Answer 29

- most recent criteria is the EULAR/PRINTO/PRES criteria - requires patient to have palpable purpura & at least one of: - diffuse abdominal pain - arthritis or arthralgia - IgA deposits on histology (biopsy) - proteinuria/haematuria

Question 30

HSP mx

Answer 30

- supportive - simple analgesia, rest & proper hydration - steroids may be considered by specialist doctors in patients with severe gastrointestinal pain or renal involvement - monitor closely whilst illness is active: - urine dipstick monitoring for renal involvement - blood pressure monitoring for hypertension

Question 31

ITP

Answer 31

Immune-mediated reduction in the platelet count Antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex Example of type II hypersensitivity reaction May follow infection or vaccination

Question 32

ITP clinical features

Answer 32

Bruising Petechial or purpuric rash Bleeding is less common & typically presents as epistaxis/gingival bleeding

Question 33

ITP ix

Answer 33

FBC - isolated thrombocytopenia Blood film Bone marrow examinations is only required if there are atypical features - lymph node enlargement/splenomegaly - high/low white cells - failure to resolve/respond to treatment

Question 34

ITP mx

Answer 34

Usually, no treatment required → resolves in 80% with 6 months, with or without treatment Advice to avoid activities that may result in trauma (eg. team sports) If platelet count v low/significant bleeding: - oral/IV corticosteroid - IV immunoglobulins - platelet transfusions in emergency (temporary measure = destroyed by circulatory antibodies)