THE SURGICAL ANATOMY OF THE PRINCIPAL NUTRIENT VESSEL OF THE TIBIA

Large segmental long-bone defects deserve consideration for reconstruc tion by vascularized, straight, high-density cortical bone grafts of c omparable diameter. If available, the tibial diaphysis would be an opt ion superior to the fibula, since the latter has known limitations whe n a large size discrepancy exists at the recipient site. However, the former choice is unrealistic except in the most unusual circumstances, since the tibia is a nonexpendable bone required for weight bearing. In anticipation of just such a unique opportunity, we have investigate d the surgical anatomy of the principal nutrient vessel of the shaft o f the tibia in 53 fresh lower limb specimens. Classical descriptions o f the pertinent vascular anatomy of the tibial shaft are inadequate, s ince the origin of its principal nutrient vessel actually may be from the popliteal bifurcation or anterior or posterior tibial vessels. In every dissection at least a single artery and vein of large caliber (b oth exceeding 1.5 mm in diameter in 85 percent of cadavers) were disco vered entering a nutrient foramen, usually at the upper third of the t ibia. Lead oxide injection studies of the nutrient artery alone in nin e cadavers demonstrated no contiguous muscle or cutaneous communicatio ns. The large size of these nutrient vessels would simplify ipsilatera l pedicled transfers of an autologous tibial shaft as well as facilita te microanastomoses for its distant transfer to other humeral, femoral , or contralateral tibial defects as in a salvage replantation. Once i mmunologic barriers have been conquered, these data should have even g reater practical clinical significance for the use of vascularized tib ial allografts for substitution in lieu of autogenous fibula or other conventional bone donor sites.