Perthes disease

• What is Perthes disease?


  Avascular necrosis of the femoral head

  In children 4-8 yrs

  Due to disruption in blood flow to femoral head -> ischaemia
• What is the full name of Perthes disease?


  Legg-Calvé-Perthes disease
• What are the RFs of Perthes disease?

  FHx

  Social deprivation

  Factor V Leiden & thrombophilias

  Second hand smoke exposure
• Who is Perthes disease most common in?


  Children 4-12 yrs (mostly 5-8 yrs)

  Male
• Pathophys - Perthes disease


  Compromised blood supply to femoral head -> bone cell death, marrow oedema & subchondral microfractures -> avascular necrosis

  As necrotic bone is resorbed, femoral head begins to fragment & collapse

  Osteoblasts & angiogenesis begins -> new bone formation -> femoral head begins to regain its original shape -> continues to remodel & shape to its final form
• How can Perthes disease be classified?


  Catterall staging

  
• What are the signs & symptoms of Perthes disease?


  Gradual onset of limp

  Hip pain (may be referred to knee)

  Restricted hip movements

  Will be no Hx of trauma

  Short stature

  Leg length discrepancy

  NOTE: pain persisting for more than 4 weeks raises suspicion for Perthes' disease
• What are the DDx of Perthes disease?


  Transient synovitis

  Septic arthritis

  Slipped capital femoral epiphysis (SCFE)

  Juvenile idiopathic arthritis
• What are the Inx for Perthes disease?


  Obs

  Full Hx & examination

  Bloods (FBC, CRP, bone profile)

  XR of hip

  MRI
• What is shown in an XR for Perthes disease?


  'Crescent sign' -> sclerosis & fragmentation of of epiphysis

  Some initial XRs may appear normal

  
• What is shown in the image?

  'Crescent sign' of Perthes disease in L femoral head

  
• What is the management of Perthes disease?


  Depends on extent of necrosis

  Bed rest

  Traction

  Crutches

  Analgesia

  Physiotherapy -> retain ROM in muscles & joints

  Regular XRs to assess healing

  Surgery (severe cases)
• What are the possible complications of Perthes disease?


  Residual deformity

  Muscle wasting

  Degenerative arthritis later in life

  Surgical complications (infections, bleeding etc.)