title: Orthogonal femoral plating: a biomechanical study with implications for interprosthetic fractures.
abstract: OBJECTIVE
  This study tests the biomechanical properties of adjacent locked plate constructs in a femur model using Sawbones. Previous studies have described biomechanical behaviour related to inter-device distances. We hypothesise that a smaller lateral inter-plate distance will result in a biomechanically stronger construct, and that addition of an anterior plate will increase the overall strength of the construct.
  
  
  METHODS
  Sawbones were plated laterally with two large-fragment locking compression plates with inter-plate distances of 10 mm or 1 mm. Small-fragment locking compression plates of 7-hole, 9-hole, and 11-hole sizes were placed anteriorly to span the inter-plate distance. Four-point bend loading was applied, and the moment required to displace the constructs by 10 mm was recorded.
  
  
  RESULTS
  We found that a 1 mm inter-plate distance supported greater moments than a 10 mm distance in constructs with only lateral plates. Moments supported after the addition of a 9- or 11-hole anterior plate were greater for both 10 mm and 1 mm inter-plate distance, with the 11-hole anterior plate supporting a greater moment than a 9-hole plate. Femurs with a 7-hole anterior plate fractured regardless of lateral inter-plate distance size.
  
  
  CONCLUSIONS
  This suggests that the optimal plate configuration is to minimise lateral inter-plate distance and protect it with an anterior plate longer than seven holes. Cite this article: Bone Joint Res 2015;4:23-8.
authors.affiliation: SUNY Upstate Medical University, 750 East Adams Street, Suite 4400, Syracuse, New York, 13090, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Auston
authors.affiliation: SUNY Upstate Medical University, 750 East Adams Street, Suite 4400, Syracuse, New York, 13090, USA.
authors.forename: F W
authors.initials: FW
authors.lastname: Werner
authors.affiliation: Upstate Bone and Joint Center, 6620 Fly Road, Suite 100, East Syracuse, New York 13057, USA.
authors.forename: R B
authors.initials: RB
authors.lastname: Simpson
keywords: Biomechanics; Inter-device distance; Interprosthetic femoral fracture; Orthogonal plating; Periprosthetic femoral fractures