Lucknow, Oct 30 : If your child complains about pain in the hip or groin or in other parts of the leg such as the thigh or knee, known as referred pain, that worsens with activity and is relieved with rest and if it persists for a week, it could be Perthes disease. Perthes disease occurs when the bone of the head of the femur (the ball of the ball-and-socket joint of the hip) gradually begins to collapse, which might require surgery if treatment is delayed, said experts at a conference on paediatric bone health, POSUPCON-2023, organised by the department of orthopaedics at Ram Manohar Lohia Institute of Medical Science (RMLIMS). Dr Abhishek Saha from the Institute of Child Health, Kolkata Medical, stated that they see 15-20 such patients every month. 'Often, kids aged between three and 11, get injured while playing and parents ignore symptoms. Eventually, when the blood supply to the rounded head of the femur (thighbone) is temporarily disrupted, and the bone cells die, they come to us. At this stage, surgery is the only option. Surgery also has a poor outcome in those above eight years,' he added. Meanwhile, Dr Prabhat of the paediatric orthopaedics department of RMLIMS mentioned another congenital condition of the hip in children called developmental dysplasia that affects one in 1,000 children in which the child's hip slips below normal. 'If a parent finds that a child's hip makes a popping or clicking sound that is heard or felt, his legs are not the same length, or one hip or leg doesn't move the same as the other side, they should immediately visit an orthopedician because if detected within six months, it can be cured by applying a plaster with the help of a belt for 18 months. However, if the disease is detected after that, surgery is required,' he said. Dr Amaar Aslam from Lucknow said underweight children, especially twins or triplets, or those who have been in the ICU, are more likely to develop a hip infection called septic arthritis. This is because their immune system is weaker. 'If septic arthritis is not treated right away, the joint can start to form and the child's hip movement can decrease. This is most common in children under 2 years old,' he added. /IANS