Study on the morphology of nutrient foramens in humerus and its surgical implications

Abstract

Long bones have large or small foramina for the entry of the blood-vessels. Such foramens are known as the nutrient foramina which are large in the shafts of the largest long bones. Such foramina lead to nutrient canals through which the blood vessels enters the bone supplying the medullary cavity. The site of entry and the direction of the nutrient foramina are almost constant and are directed away from the growing ends. The nutrient artery that passes through these foramina are the main source of blood supply to humerus and is particularly important during growth period in the embryo and foetus and also during the early stage of ossification. a. To determine the direction of nutrient foramen in humerus. b. To determine the number of nutrient foramen of humerus. c. To determine the location of nutrient foramen of humerus. The study was conducted on 120 adult humeri that were obtained from the Department of Anatomy, Sri Devaraj Urs medical college, Kolar, karnataka. Bones were segregated into right and left and observed for the direction, number and location of nutrient foramens in humerus In the present study, the percentage of humerus bones with one nutrient foramen was 87% and two foramina was 9% and absent in 4%. Single nutrient foramen on right humerus bones was 92% and left side was 4% and absent in 4%. Single nutrient foramen on left humerus bones was 83% and left side was 13% and absent in 4%. 59% of the bones had nutrient foramen that were located on the medial border. Following which, the order was Anteromedial surface in (25%), Lateral border in (5%), Posterior surface in (3%) and anterior border in (3%). 81% had the nutrient foramen that was located in the middle 1/3rd, 11% at the junction between middle 1/3rd and lower 1/3rd and 3% in the lower 1/3rd of humerus. All the nutrient foramina were directed towards the elbow joint and was away from the growing end as per the law of ossification. Nutrient artery is the main source of blood supply to long bones that enters through the nutrient foramen. The surgical and anatomical knowledge of nutrient foramen in humerus or any long bone is important for orthopaedic surgeons and general surgeons during surgical procedures on the humerus such as vascular surgeries, bone grafting and transplantation.