Xenograft
Xenografting is the transfer of tissue, of whatever nature, from one species to another. It has been widely used in orthopaedic surgery, though with mixed success. Bovine bone has been used as an aid to spinal fusion, in the management of bone tumours, and the recreation of lost bone stock at revision joint replacement. Frequently such xenograft material is mixed with autograft in an attempt to overcome the volume problem of autograft and yet the compatibility problem of xenograft.
Xenograft tissue can incorporate into a recipient. However, it does not always do so fully and may be associated with an inflammatory reaction following insertion. In recent years investigators have been looking at the use of transgenic bone from genetically-engineered pigs as a possible source of tissue for man. Laboratory studies using monkeys (if one ignores the animal rights issues for the moment) appear to be very promising. However, there are obviously major ethical issues with such a technique, so only time can tell whether it is likely to be used to any great extent in man.