Incorporation of bovine-based structural bone grafts used in reconstructive foot surgery.

Timely incorporation of bone grafts is essential to the structural rigidity in most foot and ankle surgeries. Although bovine-based xenografts possess some of the key features necessary for foot and ankle surgery, the studies evaluating the efficacy of these grafts are limited. The aim of the present study was to determine the incorporation rate of bovine-based bone grafts in foot surgery. A total of 22 patients who had undergone reconstructive foot surgery using 31 bovine-based xenografts were identified, and the rate of radiographic incorporation of the grafts was evaluated. A survival analysis was used to show the trend of the incorporation of the xenografts over time. Of the 21 grafts observed for at least 12 weeks, none showed radiographic graft incorporation by 12 weeks. The analogous numbers for 24, 36, and 48 weeks were 3 (20%) of 15, 4 (31%) of 13, and 3 (27%) of 11 grafts. A total of 19 (61.29%) of the 31 grafts studied were never observed to have incorporated radiographically, for the entire observation period. A Kaplan-Meier estimate revealed the median interval to graft incorporation was 56 weeks. Compared with previous studies, which investigated the incorporation of other types of grafts, such as autograft and allografts, we believe that xenografts incorporate more slowly. For this reason, such grafts might not be ideal for use in reconstructive foot surgery.