title: Osteogenic protein 1 device increases bone formation and bone graft resorption around cementless implants.
abstract: In each femoral condyle of 8 Labrador dogs, a non weight-bearing hydroxyapatite-coated implant was inserted surrounded by a 3 mm gap. Each gap was filled with bone allograft or ProOsteon with or without OP-1 delivered in a bovine collagen type I carrier (OP-1 device). 300 microg OP-1 was used in the 0.75 cc gap surrounding the implant. After 3 weeks, the OP-1 device enhanced implant fixation by 800% (p <0.05) in the ProOsteon group, but OP-1 bad no significant effect on implant fixation in the allograft group. By adding the OP-1 device, the volume fraction of woven bone close to the implant increased from 12% to 20% (p < 0.05) in the bone allograft group and from 6% to 25% (p < 0.05) in the ProOsteon group. The volume fraction of bone allograft decreased from 29% to 9% (p < 0.05) in the OP-1 treated group versus 33% to 30% in the allograft group not treated with OP-1. No resorption of ProOsteen was found. In conclusion, OP-1 accelerates resorption of bone allograft and enhances new bone formation around cementless implants grafted with bone allograft or semisynthetic hydroxyapatite bone substitute. Our findings do not support the use of ProOsteon alone around cementless implants.
authors.affiliation: Department of Orthopaedics, Aarhus University Hospital, Denmark. tbjensen@hotmail.com
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Jensen
authors.forename: Søren
authors.initials: S
authors.lastname: Overgaard
authors.forename: Martin
authors.initials: M
authors.lastname: Lind
authors.forename: Ole
authors.initials: O
authors.lastname: Rahbek
authors.forename: Cody
authors.initials: C
authors.lastname: Bünger
authors.forename: Kjeld
authors.initials: K
authors.lastname: Søballe
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001843:Bone Cements; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D001862:Bone Resorption / Q000517:prevention & control*; D016025:Bone Transplantation / Q000379:methods* / Q000473:pathology; D004285:Dogs; D005269:Femur / Q000473:pathology / Q000601:surgery; D007150:Immunohistochemistry; D023421:Models, Animal; D010012:Osteogenesis / Q000187:drug effects / Q000502:physiology*; D011336:Probability; D019736:Prostheses and Implants; D011474:Prosthesis Design; D011897:Random Allocation; D012016:Reference Values; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D016212:Transforming Growth Factor beta; D014184:Transplantation, Homologous / Q000473:pathology
chemical_list: D001843:Bone Cements; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D016212:Transforming Growth Factor beta