title: Anatomical and Radiological Aspects of the Supratrochlear Foramen in Brazilians.
abstract: BACKGROUND
  The supratrochlear foramen is an anatomic variation of great clinical and anthropologic interest. Although many studies addressed this subject in different ethnic groups, there are no studies regarding Brazilians.
  
  
  OBJECTIVE
  To verify the incidence and morphometric measures of the supratrochlear foramen in Brazilian humeri.
  
  
  METHODS
  A total of 330 dry humeri were analysed and divided in three groups: bones presenting the supratrochlear foramen (Group 1), bones displaying a translucent foramen (Group 2) and humeri without the foramen (Group 3). The aperture was measured with a digital vernier caliper. Radiographic pictures with different incidences were taken.
  
  
  RESULTS
  Our analysis showed that 22.5% of humeri belonged in Group 1, 41.2% in Group 2, and 36.3% in Group 3. The mean vertical diameter and the mean horizontal diameter of the supratrochlear foramen on the left side were 2.779±2.050 mm and 2.332±1.23 mm, respectively. The mean vertical diameter and the mean horizontal diameter of the foramen on the right side were 2.778±2.197 mm, and 2.365±1.396 mm, respectively. The student's t-test showed that there was no significant difference regarding the size of the foramen between both sides. The best X-ray machine setup was 50 kilo voltage and 0.08 milliamperage per second, associated with a slight increase in the distance of the x-ray tube.
  
  
  CONCLUSIONS
  The aperture seems to be the key point during the pre-operative planning of intramedullary fixation, since it has direct relation to the size of the intramedullary canal, thus, being an entity of clinical, anatomical, anthropological, radiological, and surgical interest.
authors: Anatomy Professor, Department of Morphology, Fluminense Federal University , Brazil .
authors: Carlos Aa
authors: CA
authors: Chagas
authors: Researcher, Imunopharmacology Laboratory, FIOCRUZ , Brazil .
authors: Gabriel
authors: G
authors: Gutfiten-Schlesinger
authors: Vascular Surgeon, Interventional Radiologist, Interventional Radiology Unit, Radiology Institute, University of São Paulo Medical School , Brazil .
authors: Túlio Fo
authors: TF
authors: Leite
authors: Nursing Student, Department of Morphology, Fluminense Federal University , Brazil .
authors: Lucas As
authors: LA
authors: Pires
authors: Professor, Department of Physical Therapy, Federal University of Rio de Janeiro , Brazil. Rehabilitation Science Program Augusto Motta University Center, Brazil .
authors: Julio G
authors: JG
authors: Silva
keywords: Anatomic variation; Anthropology; Humerus; Radiology; Septal aperture