The healing of autologous bone grafts after varying degrees of surgical trauma. A microscopic and histochemical study in the rabbit.

Tibial grafts in rabbits were studied using a microscopic technique in vivo that made it possible to photograph the "graft to be" at the donor site and then subsequently to observe the same graft repeatedly at the host site. With this method the effects on the graft tissues of varying degrees of surgical trauma have been tested. The period of follow-up ranged between 14 and 300 days. The grafts removed with minimal trauma showed a more rapid rapid of revascularisation. In this group the first vessels appeared on average seven days after grafting, whereas they took 15 days in the grafts which were more severely traumatised. Bone remodelling started when the vascular density resembled the more pattern and this occurred earlier and much more rapidly in the minimally injured grafts. It correlated with the presence of surviving cells, as shown by histochemical tests, and a causal relationship is suggested. It is concluded that control of trauma is important not only in the preparation of the host bed but also in procurement of the graft. Suggestions are given on techniques to minimise the surgical trauma.