An Anatomic Study of the Supratrochlear Foramen of the Humerus and Review of the Literature

Abstract

Objective: The coronoid fossa and the olecranon fossa located on the distal end of the humerus are separated by a thin bone septum. This septum may be translucent or opaque. In some cases, this septum may become perforated, and it is called supratrochlear foramen. The aim of the present study was to describe the morphology of the supratrochlear foramen of the humerus. Methods: This study was conducted on 108 dry humeri (right (R): 56, left (L): 52) belonging to adults whose age, gender, and racial properties are unknown. They were examined to determine the presence of the supratrochlear foramen. The shapes of the supratrochlear foramen were determined, and their diameters were measured. Results: The supratrochlear foramen was observed in 11 cases on the right side and 11 cases on the left side. On the right side, 5 foramens were detected to be round-shaped, 3 oval-shaped, and 3 kidney-shaped, whereas on the left side, 6 foramens were detected to be oval-shaped and 5 round-shaped. Of the 86 dry humeri with no supratrochlear foramen, 57 (R: 30, L: 27) had a translucent septum, and 29 (R: 15, L: 14) had an opaque septum. Conclusion: It is apparent that the supratrochlear foramen has been evaluated on bones generally in the literature, and there are differences in incidence rates. Owing to the clinical significance of this formation, it is thought that studying on a wider population of living individuals using radiologic imaging methods will contribute to the literature. In addition, although there are different terms used to express this formation in the literature, it is thought that adopting the name, which is commonly used as supratrochlear foramen, is most appropriate.

Olecranon aperture of the humerus: A morphometrical study

“…Mean vertical diameter in our research was 3.33 ± 1.93 mm, which is smaller than pooled results (4.09 ± 0.86 mm on the right, 4.43 ± 0.83 mm on the left side) and majority of the reported data (4.86 ± 1.32 mm; 4.21 ± 1.29 mm; 3.81 ± 0.97 mm) [7,19,20], only to be compared to the right male humeri (3.27 ± 1.46 mm) in Portuguese population [13], left side bones in Indian sample (3.37 ± 1.25 mm) [6] and right apertures in Nigerian group (3.33 ± 1.04 mm) [18].…”

“…The bones with no septum perforated were investigated for its translucency. Our results (67.1% translucent vs. 22.9% opaque) are among the ranges presented in the literature [7]. High frequency of the translucent septa in the present study may suggest higher probability of developing olecranon aperture present in the population, which should be investigated in a larger and more representative sample.…”

“…The size of the aperture seems to differ in various populations. Results by Turkish researchers presented the largest transverse diameter (average 6.09 ± 2.43 mm and 6.7 ± 2.20 mm in right male humeri [7,9], as well as in Nigerian population (6.82 ± 2.92 mm in left side bones) [18], while the smallest ones are found in Chinese (mean 3.26 ± 1.15 mm in right humeri) [15] and Brazilian cases (average 2.33 ± 1.23 mm in left side samples) [1]. Smaller apertures in latter study are believed to be due to the heterogenity of Brazilian population as a consequence of mixing native people with the colonizing and immigrating nations [1].…”

“…In our study, mean TD was 5.25 ± 3.62 mm, which is similar to another Turkish study (5.23 ± 3.74 mm in right humeri, 4.80 ± 2.65 mm in left humeri) [20], and in a range with the pooled results on 1086 bones (5.06 ± 1.08 mm, 5.45 ± 1.31 mm, for the right and left sides, respectively), with no significant difference shown between the right and left sides [2]. The only literature data from our country are from excavated remains dated from 4 th -6 th century where the transverse diameter was 18 mm on the right side, and 11 mm on the left side [10], which partially corresponds to our maximum value found in the left humerus (11.96 mm), as well as to the only finding within the recent bone material (10.4 mm), presented in the tabular literature data comparison [7]. This ancient material measurement may be also compared to the study on the medieval skeleton materials in England, where the values were up to 21 mm [3].…”

“…The coronoid fossa and the olecranon fossa of the distal epiphysis of humerus are separated by a thin bony septum which may occasionally be perforated, thus forming the variable opening [1,2]. This inconstant perforation is commonly known as "septal aperture" [3,4,5], "olecranon aperture" [2], "olecranon foramen" [6], "supratrochlear aperture" [7,8] or "supratrochlear foramen" [1,9,10], the last one being a term proposed to be incorporated into the Terminologia Anatomica [11], but it has not been added to its Second Edition which is pending approval. Recent studies suggested that this opening should be considered aperture, not foramen [2,8].…”