title: Remote ballistic fractures in a gelatine model--aetiology and surgical implications.
abstract: BACKGROUND
  Remote ballistic femoral fractures are rare fractures reported in the literature but still debated as to their existence and, indeed, their treatment. This study aimed to prove their existence, understand how they occur and determine which ammunition provides the greatest threat. In addition, fracture patterns, soft tissue disruption and contamination were assessed to aid in treatment planning.
  
  
  METHODS
  We filmed 42 deer femora embedded in ballistic gelatine and shot with four different military (5.56 × 45 mm, 7.62 × 39 mm) and civilian (9 × 19 mm, .44 in.) bullets, at varying distances off the bone (0-10 cm).
  
  
  RESULTS
  Two remote ballistic fractures occurred, both with .44 in. hollow-point bullets shot 3 cm off the bone. These fractures occurred when the leading edge of the expanding temporary cavity impacted the femur's supracondylar region, producing a wedge-shaped fracture with an undisplaced limb, deceivingly giving the appearance of a spiral fracture. No communication was seen between the fracture and permanent cavity, despite the temporary cavity encasing the fracture and stripping periosteum from its base.
  
  
  CONCLUSIONS
  These fractures occur with civilian ammunition, but cannot prove their existence with military rounds. They result from the expanding temporary cavity affecting the weakest part of the bone, creating a potentially contaminated wedge-shaped fracture, important for surgeons considering operative intervention.
authors.affiliation: Orthopaedic Surgery, Surgical Sciences, Health Sciences, Dunedin School of Medicine, University of Otago, Dunedin 9054, New Zealand. kieserdavid@gmail.com
authors.forename: David C
authors.initials: DC
authors.lastname: Kieser
authors.forename: Debra J
authors.initials: DJ
authors.lastname: Carr
authors.forename: Sandra C J
authors.initials: SC
authors.lastname: Leclair
authors.forename: Ian
authors.initials: I
authors.lastname: Horsfall
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Theis
authors.forename: Mike V
authors.initials: MV
authors.lastname: Swain
authors.forename: Jules A
authors.initials: JA
authors.lastname: Kieser
mesh_terms: D000818:Animals; D003670:Deer; D004195:Disease Models, Animal; D005260:Female; D005264:Femoral Fractures / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery; D044709:Forensic Ballistics / Q000379:methods; D005592:Fracture Fixation / Q000379:methods; D005780:Gelatin; D011859:Radiography; D016610:Tissue Embedding / Q000379:methods; D014948:Wounds, Gunshot / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery
chemical_list: D005780:Gelatin