1. The pedigree of a family in which lobster claw foot and triphalangeal thumb occurred together is presented. The affected members of two generations are described. The clinical appearances and radiological abnormalities are described in detail. Results of surgical treatment of the forefoot cleft are presented.

2. Lobster clawing of the foot is discussed with particular reference to associated hand and finger abnormalities. Triphalangeal thumb is discussed. The current and probably acceptable theory of the etiology of duplication is expanded. A hypothesis is formulated of excessive activity at the pre-and post-axial borders of the distal limb bud, followed by variable resorption, to explain not only the cause of lobster claw foot but also its occurrence in association with triphalangeal thumb.

1. Thirty-seven hips with osteoarthritis underwent phlebography before intertrochanteric osteotomy. The results of this study were reported previously.

2. Thirty-two of the hips were studied and have had a clinical, radiological and phlebographic examination about one year after operation. Three of these were excluded because of technical failures.

3. Twenty-four hips had a normal pattern of venous drainage after operation; of these only two had normal patterns before operation and the rest had had many abnormalities of venous drainage. These hips had been completely or considerably relieved of pain at rest and on activity.

4. In the other five hips, although the venous drainage pattern was still abnormal, in only one was there significant deterioration in the venous pattern; in this group there was also some alleviation of rest pain.

5. The findings are discussed in relation to the pathology of osteoarthritis and the possible influences of intertrochanteric osteotomy.

6. The pain produced by the injection of radiopaque material into the femoral head was similar to the rest pain. This finding is discussed in relation to venous obstruction and congestion.

1. Phlebography has been done on seven hips showing no radiological evidence of osteoarthritis. The findings largely confirm the work of previous authors.

2. Thirty-seven osteoarthritic hips have been examined in the same way. As the degenerative process worsens radiologically so the pattern of venous drainage deviates further from the so-called normal.

3. An attempt is made to explain the phlebographic findings in the light of known facts of the pathology of the disease.