Supratrochlear foramen of the humerus: An anatomico-radiological study with clinical implications

Abstract

BackgroundThe supratrochlear foramen (STF) of the humerus has been a neglected entity in standard anatomy and orthopaedics text-books. The knowledge of the presence of STF in a humerus may be important for preoperative planning for treatment of supracondylar fractures. The presence of STF may also result in erroneous interpretation of radiographs.MethodsThe STF was studied in detail in 384 (220 left side and 164 right side) human dried humeri of unknown sex and age. The topographical anatomy of the STF was studied in detail, morphometric measurements were taken, and the specimens were photographed. The humerus was also taken for radiological assessment of the STF and supratrochlear septum.ResultsOut of the 384 bones studied, 132 cases (34.3%) showed the presence of STF. The STF was oval, round, and triangular in shape in 123, 7, and 2 cases, respectively. The mean length of the transverse diameter for supratrochlear foramen was 6.55 mm and 5.99 mm on the left and right sides, respectively. The mean length of the vertical diameter for STF was 4.85 mm and 3.81 mm on the left and right sides, respectively. Most of the bones that had no STF showed a translucency of septum, in 56.7% of the bones.ConclusionsThe results of our study show that STF is more common on the right side, with the oval shape being more common. The respective sides did not exhibit any statistical significant differences. Presence of STF may be important for anthropological, clinical, and academic purpose.

An anatomical study of the supratrochlear foramen of the Jining population

“…This result was consistent with earlier reports (12,13,16), although it was different from the result found by Nayak and Das (22), who found that the STF was more common on the right. Recent studies by Ndou et al (24) and Mahajan et al (25) showed an incidence of STF in 32.5% and 26% of the humeri, respectively.…”

Septal aperture aetiology: still more questions than answers

“…Diwan et al [9] have shown similar frequencies of septal aperture in both sexes. There are studies where the dominance of the right humerus in septal aperture frequency has been observed [28,39]; and there are also studies where the similar incidence of septal aperture on both sides has been observed [39].…”

“…Individuals with this trait may be able to overextend the elbow joint [8]. The frequency of the foramen among mankind ranges from about 0.3% to 60%, in different races [for the details see 18,28,34,35,39]. The cause of septal aperture has been widely discussed; however, the problem has not been solved yet.…”

Study of Supratrochlear Foramen of Humerus and Its Clinical Importance

“…Number of hypothesis were proposed regarding the cause of supratrochlearforamen.Some opine that it may be a racial anomaly or atavistic 7 . Darwin mentioned STF in humans as one of the characteristic that shows man's close relationship to lower forms 8 .According to Hirsh, the thin plate of bone is always present between olecranon and coronoid fossa upto 7 years after which the bony plate occasionally becomes absorbed to form the STF 9 .Mays suggested that the perforation is the result of hyperflexion of elbow joint which resorbs the humeral septum when the coronoid process of ulna make contact with it 10 . The global statistics shows an incidence of 4.2% in White Americans, 18.4% in American Negroes , 8.8% in Germans , 18.1% in Japanese, 21.7% in African Negroes, 43.9% in Egyptians and 9.4% in Italian populations .Theincidence is alsodifferent in different parts of Indian population, 27.4% in Eastern Indians,32% in Central Indians,27.5%in North Indians and 28% in South Indians 11 .…”