title: Effects of local infusion of OP-1 on particle-induced and NSAID-induced inhibition of bone ingrowth in vivo.
abstract: Excessive polyethylene wear particles from joint replacements may lead to periprosthetic osteolysis and loosening. Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease fracture healing and bone ingrowth. We hypothesized that continuous local infusion of OP-1 (BMP-7) would increase local bone formation in the presence of two different adverse stimuli, polyethylene particles, and an oral NSAID. The Drug Test Chamber (DTC) was implanted in the proximal tibia of mature rabbits. The tissue growing into the chamber was exposed to OP-1 solution (110 ng/day), which was infused via an osmotic pump. Infusion of OP-1 alone for 6 weeks enhanced local bone formation in the chamber by 80% (p < 0.05) over infusion of carrier alone. In the presence of polyethylene particles, infusion of OP-1 increased local bone formation by 38% (p < 0.05) over treatment with particles and carrier. Oral administration of NSAID reduced local bone formation by 58% (p < 0.05); this suppressive effect caused by NSAIDS was completely reversed by the infusion of OP-1 (p < 0.05). These findings underline a potential role for local treatment with OP-1 to increase bone formation in the presence of potentially adverse stimuli such as polyethylene wear particles or NSAID use.
authors.affiliation: Department of Orthopaedic Surgery, Stanford University, Stanford, California, USA.
authors.forename: T
authors.initials: T
authors.lastname: Ma
authors.forename: E R
authors.initials: ER
authors.lastname: Nelson
authors.forename: T
authors.initials: T
authors.lastname: Mawatari
authors.forename: K J
authors.initials: KJ
authors.lastname: Oh
authors.forename: D M
authors.initials: DM
authors.lastname: Larsen
authors.forename: R L
authors.initials: RL
authors.lastname: Smith
authors.forename: S B
authors.initials: SB
authors.lastname: Goodman
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects*; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D010012:Osteogenesis / Q000187:drug effects*; D020959:Polyethylene; D011817:Rabbits; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D016212:Transforming Growth Factor beta; D020959:Polyethylene; D000469:Alkaline Phosphatase