1. Intra-osseous venographs have been obtained in twenty-eight hips affected by Perthes disease and in twenty normal hips after the injection of opaque medium into the femoral neck.

2. In the normal hips the contrast medium drained rapidly into the local veins; none flowed distally into the diaphysis.

3. In the initial and in the fragmentation stages of Perthes' disease some contrast medium always flowed into the diaphysis and the flow into the local veins was greatly reduced.

4. In the restitution stage the venographs approached normal.

5. The implications of these findings are discussed.