system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Perthe's disease is treated by -
assistant
The correct answer is  The head is required to be kept inside the acetabulum while the revascularisation takes place (head containment).
This may be achieved by conservative methods (plaster, splint etc) or by operation (containment osteotomy).