Effect of size and shape of the allogeneic bone grafts in bridging experimental ulnar gap in rabbits.

ABSTRACT

Partially decalcified allogeneic bone matrix was cut into the sizes and shapes of cylinders, bone strips and pulverized bone powder. Large osteoperiosteal gaps were created in rabbit's ulnae. A total of 14 gaps were filled with bone strips, 20 with powder, six with cylinders and two were left unbridged to serve as control. The healing of gap was assessed at intervals with a maximum follow up of 24 weeks. Clinically at 12 weeks the bone strips could not be moved separately from each other, the whole tubular bone had also united whereas gaps filled with bone powder did not diminish in size. Radiologically union occurred earlier (around 12 weeks) in bone strips as compared to cylinders (approx-18 weeks). With bone powder only a faint line of the remnants was visible. Gross examination findings of the grafted area were in concurrence with the clinical and radiological findings. Overall the gaps filled with bone strips had 100 per cent success with early osteo induction and remodelling as compared to long cylinders whereas gaps filled with bone powder had complete failure.