Topographic variations and morphometric characterisation of the humeri nutrient foramina in the South African Populations: implications for fracture repair and healing

Abstract

Abstract Purpose Fractures of the humerus are common on the midshaft of the bone, often causing injury to the nutrient artery. Successful fracture repair and healing requires preservation of the blood supply to the long which is conveyed through the nutrient foramina (NF). The topography of long bone NF varies in different populations. These variations can affect the preservation of blood supply to long bones during fracture repair management. The current study aimed to determine the topography and morphometry of the NF of the humerus in different populations of South Africa including the SAA, SAED and SAMA. Methods The study examined 596 dry humeri from the three South African populations. The parameters examined included the presence, number, location, position, size and direction of the NF. Results The NF were present in 97.1% of the humeri. Majority of bones (76.8%) evinced a single nutrient foramen. The number of NF varied across the different population groups (P < 0.0001), with SAA having more humeri with a single NF and SAED having more humeri with double NF. The position of NF varied within and across populations (P = 0.002). Males in SAED had a higher mean FI on both the right (p = 0.03) and left (p = 0.022) sides than females. SAED had a lower mean FI than SAMA (P = 0.001). All humeri showed dominant-sized NF. The location of NF varied across different populations (P < 0.0001), with SAA having higher NF located on the anteromedial surface and medial border, and SAED having higher NF located on the lateral border (P < 0.0001). NF were directed towards the distal ends of the shafts in 99.8% of bones and towards the proximal end in 0.2% of bones. Conclusions The topography and morphometry of the nutrient foramina of the humerus are variable in the South African populations. Knowledge of the NF variations may aid in the management of humerus fractures.