1. In the natural course of Legg-Perthes disease there is a wide variation in the severity of the process.
2. Marked changes in the femoral neck and lateral expansion or central depression of the femoral head indicate a bad prognosis. In general, the younger tile patient at the onset of the disease, the better the prognosis.
3. Premature symmetrical or asymmetrical growth arrest of the capital femoral epiphyseal cartilage plate may occur and contribute to the deformity.
4. In tile presence of gross changes on the roentgenograms, there may be few or no symptoms in early adult life. However, as the patient becomes older, progressive disability does occur.
5. Therefore, patients should be treated and treated early. Inasmuch as there seems to be no significant difference in the results obtained by ambulatory or non-ambulatory treatment, non-weight-bearing on cruteches is sufficient in a cooperative patient with unilateral involvement.