1. Department of Orthopedic Surgery, Rush University, Rush‐Presbyterian‐St.Luke's Medical Center, Chicago, Illinois, U.S.A.
2. Department of Immunology/Microbiology, Rush University, Rush‐Presbyterian‐St.Luke's Medical Center, Chicago, Illinois, U.S.A.
3. Department of Biochemistry, Rush University, Rush‐Presbyterian‐St.Luke's Medical Center, Chicago, Illinois, U.S.A.
4. Department of Orthopedic Surgery, University of Pecs, Hungary