title: Mechanical properties of gamma irradiated morselized bone during compaction.
abstract: This study examined the effects of gamma irradiation on the compressive properties of morselized cancellous bone from human femoral heads. Twelve bone samples, mean age of 68 years (range 92-39), were divided into 3 groups (N=12) of varying irradiation level (0, 15 and 25 kGy). Each specimen was compacted in a controlled fashion in steps of 0.5 mm at 0.5 mm/min (up 12 mm). The load and stiffness increased with compaction, but this relationship was not linear. There was no statistical significant difference in the compacting load or stiffness between groups (p>0.05) until the last 1 mm of compaction, where the 25 kGy group were significantly stiffer compared to controls but not different to the 15 kGy group. This may be due to decreased interlocking of bone particles caused by higher irradiation levels resulting in a stiffer graft.
authors.affiliation: Orthopaedic Research Laboratories, University of New South Wales, Prince of Wales Hospital, Sydney, Australia.
authors.forename: Adam M
authors.initials: AM
authors.lastname: Butler
authors.forename: David A F
authors.initials: DA
authors.lastname: Morgan
authors.forename: Richard
authors.initials: R
authors.lastname: Verheul
authors.forename: William Robert
authors.initials: WR
authors.lastname: Walsh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods; D001842:Bone and Bones / Q000473:pathology*; D002356:Cartilage / Q000473:pathology; D005270:Femur Head / Q000473:pathology* / Q000528:radiation effects*; D005720:Gamma Rays; D006801:Humans; D008422:Materials Testing; D019563:Mechanics; D008875:Middle Aged; D010003:Osteoarthritis / Q000473:pathology / Q000628:therapy; D015207:Osteoarthritis, Hip; D013314:Stress, Mechanical; D013718:Tensile Strength; D013997:Time Factors