1. Valgus deformity of the knee, following injury in childhood, is commonly the result of premature closure of the lateral portion of the epiphyseal cartilage plate of the distal end of the femur. The type of injury producing this premature closure is a crushing of the cartilage plate, and is most commonly received from a fall from a considerable height.

2. Severe angulation of the knee occurs if the injury takes place in a young child. Marked loss of function is caused by the degree of angulation and shortening.

3. Supracondylar osteotomy of the open-wedge type, with lengthening of the soft structures on the lateral side of the knee, gives excellent anatomical reconstruction and added length to the femur.

4. If compensatory deformity of the tibia is present, this should also be corrected by open-wedge osteotomy, which gives additional length to the leg.

5. The osteotomies should be carefully outlined on tracings of the teleoroentgenograms.

6. A triangular, full-thickness wedge of iliac bone has been found to be the most advantageous type of bone graft to place in the open wedge.

7. In the growing child with developing deformity, open-wedge osteotomy should be performed before the medial condyle has overgrown the lateral condyle by more than one inch. The operation should be repeated as often as necessary during the period of growth. In this manner, added length is obtained with each osteotomy; the deformity is never severe; and correction is easier to obtain.

8. Arrest of the corresponding epiphyseal cartilage plate of the normal femur should be performed before the normal femur has overgrown the involved femur by more than two inches, providing the expected final height is satisfactory with this loss of growth.

9. If necessary to give a more desirable final height, femoral lengthening may be performed. It should not be done until the valgus deformity has been fully corrected.