[1] Univ Maryland, Sch Med, Dept Orthopaed, R Adams Cowley Shock Trauma Ctr, 22 South Greene St,T3R62, Baltimore, MD 21201 USA
[2] Med Univ South Carolina, Dept Orthopaed, Mt Pleasant, SC USA
[3] Johns Hopkins Bloomberg Sch Publ Hlth, Ctr Injury Res & Policy, Baltimore, MD USA