When should I consider referring a child with suspected Perthes disease to a specialist?

When considering referring a child with suspected Perthes disease to a specialist, it is important to note that Perthes disease is a key diagnosis that demands early intervention and treatment ¹,²,³. Therefore, specialist assessment is generally indicated if Perthes disease is suspected or cannot be ruled out in primary care.

You should arrange urgent specialist assessment if the child with a limp (which could be due to Perthes or another serious condition) presents with any of the following red flags:

• Has a fever and/or other red flags suggesting serious pathology, such as pain waking the child at night, redness, swelling, or stiffness of the joint or limb ¹,²,³.
• Exhibits weight loss, anorexia, fever, night sweats, or fatigue ¹,²,³.
• Has an unexplained rash or bruising ¹,²,³.
• Experiences limp and stiffness that is worse in the morning ¹,²,³.
• Is unable to bear weight or has painful limitation of range of motion ¹,²,³.
• Presents with severe pain, anxiety, and agitation after a traumatic injury ¹,²,³.
• Has a palpable mass ¹,²,³.
• Is suspected of being maltreated ¹,²,³.
• Is younger than 3 years of age, as transient synovitis is rare in this age group and septic arthritis is more common ¹,²,³.
• Is older than 9 years of age with painful or restricted hip movements (particularly internal rotation), to exclude slipped upper femoral epiphysis ¹,²,³.

You should arrange specialist assessment (with the urgency depending on clinical judgement) if:

• There is uncertainty about the cause of the limp, in which case referral should be to paediatric orthopaedics or orthopaedics ¹,²,³.
• The cause of the limp cannot be managed in primary care ¹,²,³.
• A child presents with a limp on multiple different occasions ¹,²,³.
• Symptoms have not resolved completely or there is any uncertainty about the diagnosis after initial primary care management (e.g., for suspected transient synovitis) ¹.