The olecranon aperture of the humerus: a meta-analysis with anthropological and clinical discussion

Abstract

The olecranon aperture is an anatomical variant of the humerus that communicates the olecranon fossa with the coronoid fossa. It is also known as the supratrochlear foramen. Older anatomical textbooks refer to it as a rare variation caused by the perforation of the thin bony plate which separates both fossae. This anatomical variant may be confused as an osteolytic lesion of the humerus in radiographic images. The present work aims to perform a meta-analysis of the olecranon aperture. Heterogeneity between studies was evaluated using I2 estimation and the Cochran Q statistic test. A random effect model was used for all analyses. A total of sixty-one studies (20,338 humeri) were included in this meta-analysis. The pooled prevalence of the olecranon aperture was 21.9% (95% confidence interval: 18.6% to 25.3%). This variant was more commonly found in female than in male bones (statistically significant difference). The olecranon aperture is a common anatomical variant among the general population, although individuals from Africa possess a higher predisposition to develop it. The name supratrochlear foramen is incorrect, as foramina are conduit to vessels or nerves, as such, we propose the term olecranon aperture.