Morphometric Study of Diaphyseal Nutrient Foramen in dried Nigerian femurs: Implications for Microvascular bone graft.

Abstract

The femur is supplied principally by the diaphyseal nutrient artery which enters the bone through the diaphyseal nutrient foramen (DNF). This supply is vital for the process of bone ossification, growth and healing. Surgically aided bone defect repair such as microvascular bone graft, relies greatly on the vascularity of the femur for survival of donor and recipient bones.

This study analyzed the number and location of DNF in 95 dried adult Nigerian femurs (43 rights, 52 lefts) of unknown sexes. The direction of the nutrient canal with respect to the growing end and the foramen Index (FI) were also determined.

Majority of the bones (77.89%) had single DNF while only 21.1% had double. The single DNF was located on the Linea aspera (LA) in 48.42%, on the medial lip of LA in 17.89%, on the lateral lip of LA in 12.63%, on the medial surface in 18.95% and on the lateral surface in 2.11%. Double DNF occurred most frequently on the medial surface and Linea aspera. The mean foramen index was 42.46 and all, but one, femurs had their nutrient canal directed away from the growing end.

The occurrence of DNF is frequent in the postero- medial surface, less frequent in the lateral surface and rare in anterior surface of the shaft. Adequate knowledge of the location of DNF is important for improving the outcome of microvascular bone graft and ensuring adequate endo-periosteal blood flow.

Keywords: Diaphyseal nutrient foramen, femur, Microvascular bone graft, Foramen index.