ANATOMICAL FEATURES OF THE STERNUM IN A KENYAN POPULATION

Abstract

Variations in breadth, thickness and asymmetry of the sternum may increase the risk of migration of suture material through the sternum during median sternotomy. We investigated these anatomical features in a Kenyan population. Eighty one dry adult sterna were studied at the Department of Human Anatomy, University of Nairobi, Kenya. Sternal asymmetry was taken as displacement of the manubriostarnal junction by more than 10mm from the midline. Data was analyzed by SPSS version 17.0 and sex differences determined using student’s t- test. The average thickness of the manubrium was 12.1 ± 1.3mm and 10.4 ± 1.2mm in males and females respectively (p= 0.163). The body thickness was 10.2 ± 1.2mm and 8.3 ± 1.1mm in males and females respectively (p= 0.159). In 13 cases (16.0%), the average manubrial thickness was less than 10mm, while in 7 cases (8.6%), the average body thickness was less than 8mm. Asymmetrical sterna were present in 16 cases (19.8%). The Kenyan sternum showed morphometric variations from previous reports. The variations may complicate median sternotomy and have been associated with fracture susceptibility. Further research is needed to correlate these findings. However, careful evaluation of chest injuries and due caution during median sternotomy are recommended