[The limping child: a red flag for every physician].

A limping gait pattern in a child is a red flag for every physician until proven otherwise. Among the most common causes are coxitis fugax, infection (septic arthritis, osteomyelitis), Perthes disease, and slipped capital femoral epiphysis, depending on the age of the patient. A high index of suspicion is required because clinical findings are often subtle, and the diagnosis may be present even if initial radiographs are negative. A missed or delayed diagnosis may have devastating consequences. Therefore, this paper describes the main characteristics of different causes of a limping child, based on four typical cases. Tools are provided to recognize each diagnosis. Early referral to a paediatric orthopaedic surgeon is recommended.