title: A helmet to the flank.
authors: Washington University School of Medicine, St. Louis, MO, USA.
authors: T Keefe
authors: TK
authors: Davis
authors: Washington University School of Medicine, St. Louis, MO, USA.
authors: Garmina
authors: G
authors: Agrawal
authors: Mercy Family Practice, Sullivan, MO, USA.
authors: Matthew
authors: M
authors: Tiefenbrunn
mesh_terms: D000293:Adolescent; D003937:Diagnosis, Differential; D021501:Flank Pain / Q000175:diagnosis*; D005538:Football / Q000293:injuries; D006801:Humans; D006869:Hydronephrosis / Q000000981:diagnostic imaging; D007682:Kidney Pelvis / Q000473:pathology*; D008297:Male; D014057:Tomography, X-Ray Computed; D014517:Ureteral Obstruction / Q000151:congenital / Q000175:diagnosis*