1. Department of Basic Medical Sciences, Neuroscience and Sense Organs, Section of Human Anatomy and Histology, University of Bari, 70124 Bari, Italy
2. Department of Clinical and Experimental Medicine, University of Foggia, 71100 Foggia, Italy
3. Department of Medical Sciences, University of Torino, 10126 Torino, Italy
4. Department of Orthopedics, Washington University School of Medicine, St. Louis, MO 63110, USA