A Study on Diaphyseal Nutrient Foramen of Humerus

Abstract

Objective: The aim of this study is to provide detailed data about the nutrient foramen (NF) of the humerus, the entry point of the nutrient artery, used in order to avoid damaging the nutrient artery, which has an important role in the nutrition of the humerus, during surgical approaches to the humeral diaphysis. Methods: This study was performed on 113 (58 right, 55 left) humeri. The number, direction, location, position, size and foraminal index of the nutrient foramina (NFs) were evaluated. In addition, total length of the humerus and distance between NF and proximal end of the humerus were measured. Results: One NF was observed on 86 of 113 (76.11%) humeri, two NFs on 17 of 113 (15.05%) humeri, 3 NFs on the one right sided humerus and no NF was observed on 9 of 113 (7.96%) humeri. While 122 (99.19%) of all NFs were directed distally, one (0.81%) NF was directed horizontally. Eighty-six (69.92%) NFs were located on the anteromedial surface, while 18 (14.63%) NFs were found to be located on the medial border, 12 (9.76%) NFs on the posterior surface, 4 (3.25%) NFs on the anterolateral surface and 3 (2.44%) NFs on the lateral border. 20G sized NF was detected on 50 of 123 (40.65%) NFs. 14G and 16G sized NFs were not detected. 5 (4.07%) NFs were located on the proximal 1/3, 113 (91.86%) NFs were located on middle 1/3 and 5 (4.07%) NFs were located on distal 1/3 of the humerus. The mean values of total length of the humerus, distance between NF and proximal end of the humerus and foraminal index were found out to be 301.68±20.61 mm, 166.70±32.50 mm and 55.33±9.48%, respectively. Conclusion: It is found out that there is usually one NF on the humerus and that this foramen is directed distally, localized on the anteromedial surface and the middle 1/3 of the humerus and sized at 20G. And also, we observed horizontally directed NF on the humerus. To our knowledge, there is no study which observed horizontally directed NF. There may be differences between populations about the morphology and morphometry of NF. Therefore, being aware for the morphology, morphometry and variations of the NF is important for the orthopaedic surgeons in surgeries such as fracture repairing and vascularized bone graft in order to avoid damaging the nutrient arteries.