Cadaveric Evaluation of Calcaneal Autograft Harvest: Can We Optimize Bone Harvesting?

Bone autografts are commonly used to augment arthrodesis sites and enhance the biologic environment necessary for successful fusion. Autogenous bone may be harvested from several donor locations, including the anterior and posterior iliac crest, proximal and distal tibia, and notably the calcaneus. Complication rates of calcaneal graft harvest have varied widely in the literature with several different techniques from open to percutaneous methods. The purpose of this study was to assess optimal zones of graft volume while minimizing donor-site morbidity. Twenty, ten matched-pairs, fresh-frozen cadaveric below-knee specimens were used for this study. The posterior tuber of the calcaneus was measured in height and equally divided into 3 distinct zones. A 7-mm Medline bone graft harvester was inserted perpendicular to the lateral calcaneal wall and advanced in a single pass to obtain cancellous autograft from the calcaneus. Graft volume as well as distance to adjacent structures at risk were measured. We found no statistical significance in graft volume among the three zones; however, we did note a significant difference in distance from the sural nerve between zones 1 and 2, and between zones 1 and 3. We found an average volume of 0.59, 0.41, and 0.61 grams³ for zones 1, 2, and 3, respectively. These findings suggest calcaneal bone graft harvest remains a safe procedure and enables to obtain consistent graft volume. Further clinical studies are recommended to confirm these results and guide future surgical practices.Level of Evidence: Level IV: Cadaveric study.