How is it assessed?
The hip joint is a deep structure so investigations are required for diagnosis. The following tests may be used -:
- X-ray – plain x-rays are likely to show changes in the femoral head. The child will usually have a series of x-rays over the course of treatment.
- Ultrasound of the hip joint – this test can reveal whether there is fluid in the hip joint but cannot determine the cause.
- A Magnetic Resonance Imaging (MRI) scan is not usually necessary. It is used if the diagnosis is not clear and can show the earliest changes associated with the disease before they are visible on X-ray. MRI may be used to plan surgical treatment.
Age at diagnosis
Young children aged 2-6 have a better prognosis. This is because young children have many years of growth left – they have the maximum capacity for re-growth and re-modelling of the femoral head back to a normal shape once healing has occurred. Older children do not have years of growth left and deformity of the femoral head is more likely to persist. For this reason older children are more likely to have active treatment in the form of surgery and bracing to prevent deformity from developing whilst healing occurs.
