High-yield Flashcards
Limp ddx
- developmental dysplasia of the hip
- perthes disease
- transient arthritis/synovitis
- septic arthritis
- slipped upper femoral epiphysis (SUFE)
DDH
femoral head does not sit fully in the acetabulum → easily dislocated
DDH risk factors
- first born child
- breech presentation
- females
- fmhx of ddh
- oligohydramnios
- birth weight > 5kg
- congenital calcaneovalgus foot deformity
DDH screening
- 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
DDH signs
- painless limp
- delayed walking
- affected leg is shorter → due to atrophy of hip muscles
- more skin folds on affected leg
DDH ix
- NIPE → barlow (dislocate) & ortolani (relocate)
- USS of hip (gold standard)
- x-rays → 1st line if child > 4.5 months
DDH mx
- most unstable hips spontaneously stabilise by 3-6 weeks of age
- younger kids → Pavlik harness (before 6 months)
- older kids → combined femoral & pelvic osteotomies
Perthes disease
avascular necrosis of the femoral head → flattened & fragmented femoral head is unable to rotate smoothly in acetabulum → restricts mobility
Perthes disease clinical features
- presents in primary school kids, 5x more common in boys
- hip pain - develops progressively over a few weeks
- limp
- stiffness & reduced range of movement
Perthes disease ix
- hip x-ray → increased density in femoral epiphysis
- technetium bone scan/MRI if normal x-ray and symptoms persist
Perthes disease mx
- <6 years - observation, analgesia & bracing
- > 6 years - surgical repair
Perthes disease complications
- osteoarthritis
- premature fusion of growth plates
Transient synovitis
- inflammation of the synovium
- acute hip pain following a recent viral infection & typical age group is 3-8 years
Transient synovitis clinical features
- acute limp/refusal to weight bear
- mild/no fever
- pain on exercise, comfortable at rest
- limited internal rotation
Transient synovitis ix
Diagnosis of exclusion
- blood cultures
- USS-guided joint aspiration
- hip x-ray
Transient synovitis mx
- rest
- analgesia - NSAIDs
Septic arthritis risk factors
- osteomyelitis
- sickle cell anaemia
- diabetes/immunocompromised
Septic arthritis clinical features
- 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
Septic arthritis ix
- USS-guided joint aspirate
- blood cultures
Septic arthritis mx
- joint aspiration
- IV flucloxacillin for 4-6 weeks (IV clindamycin in pen allergic)
- child with limp/hip pain & fever = same day assessment
SUFE risk factors
- secondary school boys (10-15)
- overweight
SUFE clinical features
- 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
SUFE ix
AP & lateral (typically frog-leg) x-ray views
SUFE mx
- bed rest and crutches
- orthopaedics referral & internal fixation (single cannulated-screw placed in the centre of the epiphysis)
SUFE complications
- osteoarthritis
- avascular necrosis of the femoral head
- chondrolysis
- leg length discrepancy
HSP
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
HSP clinical features
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
HSP ix
- FBC & blood film
- renal profile
- serum albumin
- CRP
- blood cultures
- urine dipstick
- urine protein:creatinine ratio
- blood pressure
HSP diagnosis
- 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
HSP mx
- 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
ITP
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
ITP clinical features
Bruising
Petechial or purpuric rash
Bleeding is less common & typically presents as epistaxis/gingival bleeding
ITP ix
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
ITP mx
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)
