The use of OP-1 in femoral impaction grafting in a sheep model.
The aim of this pilot study was to examine bone graft incorporation in femurs impacted with allograft bone alone (control group) or with allograft containing the bone morphogenetic protein OP-1 (BMP-7) (OP-1 group) in a sheep model of cemented hemiarthroplasty. Two sheep in each group were sacrificed at 6, 18 and 26 weeks. Successful bone graft incorporation was evident in both groups by six weeks but in the OP-1 group, there had been more extensive resorption of the graft. There was one case of excessive stem subsidence in the OP-1 group at six weeks. By 18 weeks, there was remodelling and trabeculation of the new bone in the OP-1 group, but this appeared less advanced in the control group. By 26 weeks, there was remodelling of bone in the graft bed. The results of this small study suggest that OP-1 promotes initial graft resorption, thus hastening bone graft incorporation and remodelling in femoral impaction grafting. The one case of stem subsidence may be associated with the early resorption seen in the OP-1 group and reinforces the need for further studies, examining dose response and using precise measures of stem movement, before this BMP is used in femoral impaction grafting at revision hip arthroplasty.
Department of Orthopaedics and Trauma, University of Adelaide and Royal Adelaide Hospital, L4 Bice Building, Adelaide, South Australia 5000, Australia. mmcgee@mail.rah.sa.gov.au
Margaret A
MA
McGee
David M
DM
Findlay
Donald W
DW
Howie
Angelo
A
Carbone
Peter
P
Ward
Roumen
R
Stamenkov
Tara T
TT
Page
Warrick J
WJ
Bruce
Corinna I
CI
Wildenauer
Carol
C
Toth
D000818:Animals; D001178:Arthroplasty; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005269:Femur / Q000601:surgery*; D010012:Osteogenesis; D012756:Sheep; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014184:Transplantation, Homologous
D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D016212:Transforming Growth Factor beta