The Importance of the Supratrochlear Foramen of the Humerus in Humans: An Anatomical Study

Abstract

Background

The supratrochlear foramen (STF) is an important and relatively common anatomic variation in the lower end of the humerus in humans. Its structure has received increased attention in recent years. Anatomical knowledge of STF is useful for anatomists, anthropologists, orthopedic surgeons, and radiologists. This aperture is of great interest to anthropologists who claim it as one of the points in establishing a relationship between humans and lower animals. The goal of this study was to describe the features of STF of the humerus in the Turkish population.

Material/Methods

All bones were obtained from the Department of Anatomy, Faculty of Medicine and Department of Antrophology, University of Mustafa Kemal, Hatay. A total of 166 dried humeri (83 right side and 83 left side), of which 78 belonged to males and 88 to females, were examined to determine the presence of supratrochlear foramen. Digital vernier calipers were used to measure the maximum width (transverse) and height (vertical) of the STF.

Results

Out of 166 bones, the foramen was present in 18 humeri (4 right side and 14 left side), showing the incidence as 10.8% with unpaired humeri. We observed 4 types of shape: oval, round, triangular, and sieve-like. The average diameter of the long (transverse) axis was 5.93±1.68 mm and the short (vertical) axis was 4.06±0.89 mm. Some of the bones showed translucency of the bony septum, found in 17 (20.5%) on both sides of the humeri.

Conclusions

There are few studies about STF in the Turkish population. Knowledge of supratrochlear foramen in the distal humerus in humans is important in diagnostic orthopedics, in intramedullary nailing of the humerus, and in possibly increasing the risk of future low-energy fractures. In addition, STF is a radiolucent area in radiographs and may be misinterpreted as an osteolytic or cystic lesion.