Analysis of miniature single- and double-notch bending specimens for estimating the fracture toughness of cortical bone

Jordan McCormack, Xiang S. Wang, Susan M Stover, Jeffery C. Gibeling, David P Fyhrie

Research output: Contribution to journalArticle

2 Scopus citations


Studies of the fracture behavior of cortical bone have determined multiple toughening mechanisms that are active during propagation of a crack. Common methods for measuring bone fracture toughness use single-notched specimens often in four-point (SN4PB) or three-point bending (SN3PB). A double-notch four-point bending (DN4PB) specimen is useful to study prefailure damage at the crack tip. Total failure occurs at one notch and only partial failure at the other allowing study of prefailure damage in the unbroken notch. There is no widely known method for calculating the fracture toughness of bone using a DN4PB specimen. A method for calculating the fracture toughness of cortical bone using a DN4PB is developed here and compared with results for a common SN3PB specimen. The new double-notch method permits using a single specimen to measure apparent fracture toughness and to study both pre- and postfailure microdamage in the bone matrix. When and how to use the new and the established test specimens for understanding bone mechanics is discussed.

Original languageEnglish (US)
Pages (from-to)1080-1088
Number of pages9
JournalJournal of Biomedical Materials Research - Part A
Volume100 A
Issue number4
Publication statusPublished - Apr 2012



  • cortical bone
  • crack propagation
  • DN4PB
  • fracture toughness
  • SN3PB

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biomaterials
  • Ceramics and Composites
  • Metals and Alloys

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