1 Department of Orthopedics and Traumatology, University Hospital Queen Giovanna-ISUL, Medical University of Sofia, 8 Bialo More St., BG 1527, Sofia, Bulgaria. georgievgp@yahoo.com.
2 Department of Cardiology, University Hospital "Prof. Al. Tschirkov", Medical University of Sofia, Sofia, Bulgaria.
3 Department of Anatomy, Histology and Embryology, Medical University of Sofia, Sofia, Bulgaria.