Pathophysiology: Legg-Calve-Perthes disease is a childhood condition that affects the hip, where the thighbone (femur) and pelvis meet in a ball-and-socket joint. It occurs when blood supply is temporarily interrupted to the ball part (femoral head) of the hip joint. Without sufficient blood flow, the bone begins to die — so it breaks more easily and heals poorly. Signs & Symptoms: Common symptoms include hip, knee, or groin pain, exacerbated by hip/leg movement, especially internal hip rotation.
Treatment: X-Rays of the hip may suggest and/or verify the diagnosis. X-rays usually demonstrate a flattened, and later fragmented, femoral head. A bone scan or MRI may be useful in making the diagnosis in those cases where x-rays are inconclusive. Usually, plain radiographic changes are delayed 6 weeks or more from clinical onset. So bone scintography and MRI are done for early diagnosis. Treatment is done by removing mechanical pressure from the joint until the disease has run its course.
Statistics:The conventional quotation for the incidence of LCPD is the number per 100,000, usually for age < 15 years. The incidence of LCPD ranges widely, from 0.4 in Eastern India (Vellore-Taluk area) to 29.0. There is a 10-fold variability in incidence in India; 0.4 in the east (Vellore Taluk)  to 4.4 in the west.