遠位脛骨自家骨採取の死体評価：骨採取を最適化できるか？

Autogenous bone grafting is a useful tool for the foot and ankle surgeon to augment their arthrodesis procedures. Distal tibial graft has been shown to be increasingly useful with the benefit to those with limited scope of practice while maintaining low morbidity. While techniques of harvest are surgeon dependent, no study has assessed optimal anatomic location of obtaining distal tibial graft.

The primary goal of this study was to evaluate zones of distal tibial graft harvest to assess the location of optimal graft volume while also identifying structures at risk through a percutaneous approach with the use of powered bone graft harvesting instrumentation.

Twenty individual (ten-matched pairs) fresh-frozen cadaveric below-knee specimens were used. The distal tibia was subdivided into three equal zones.

A 7mm bone graft harvester was inserted perpendicular to the tibia to allow for graft harvest from each respected zone. Post harvest dissection was performed to assess structures at risk.

A significant increase (p<0.001) in autogenous harvest was found in the medial zone (zone 3) with a mean harvest of 1.12 grams, while also found to be closest in proximity to the tibialis posterior tendon as well as saphenous vein and nerve. The lateral zone (zone 1) was significantly closer to the tibial crest and tibialis anterior tendon.

Distal tibial autograft remains a safe means for obtaining autogenous graft, our findings suggest that harvest planning closest to the medial malleolus (zone 3) may yield greater graft volume.