1. The stability of intertrochanteric fractures is primarily determined by the integrity of the medial cortex of the fracture fragments and the surgeon's ability to obtain accurate and stable apposition of the medial cortices of the major fragments.
2. In the presence of comminution of the medical cortex sufficient stability is not achieved by mere anatomical reduction of the fragments.
3. We have developed a valgus osteotomy technique for the treatment of unstable intertrochanteric fractures which makes the plane of the fractures more horizontal, approximates the cortical surfaces of the two major fragments, and places the neck of the femur in a valgus position.
4. The results in 100 cases of unstable intertrochanteric fracture treated in this manner are reported and the technique for osteotomy and insertion of a short 135-degree I-beam nail is described.