title: Temporal effects of a COX-2-selective NSAID on bone ingrowth.
abstract: The effects of a short course of a COX-2 inhibitor on bone healing when the drug is discontinued are unknown. We examined the effects of rofecoxib on bone ingrowth over a 6-week period using a well-defined animal model. The Bone Harvest Chamber was implanted bilaterally in mature rabbits. After osseointegration of the chamber, the following treatments were given for 6 weeks each, followed by a harvest in each case: control-no drug; oral rofecoxib (12.5 mg/day) for the first 2 of 6 weeks; washout period-no drug; oral rofecoxib for the last 2 of 6 weeks; washout period-no drug; rofecoxib given continuously for all 6 weeks. Harvested specimens were snap-frozen, cut into serial 6-microm sections, and stained with hematoxylin and eosin and alkaline phosphatase (osteoblast marker), and processed using immunohistochemistry to identify the vitronectin receptor (osteoclast-like cells). Rofecoxib given continuously for 6 weeks yielded statistically less bone ingrowth compared to the control treatment. Rofecoxib given during the initial or final 2 weeks of a 6-week treatment did not appear to interfere with bone ingrowth. This suggests that the effects of COX-2 inhibitors on bone are less profound when the drug is administered for a short period of time.
authors.affiliation: Department of Orthopaedic Surgery, Stanford University Medical Center, Stanford, California 94305-5341, USA. goodbone@stanford.edu
authors.forename: Stuart B
authors.initials: SB
authors.lastname: Goodman
authors.forename: Ting
authors.initials: T
authors.lastname: Ma
authors.forename: Lance
authors.initials: L
authors.lastname: Mitsunaga
authors.forename: Keita
authors.initials: K
authors.lastname: Miyanishi
authors.forename: Mark C
authors.initials: MC
authors.lastname: Genovese
authors.forename: R Lane
authors.initials: RL
authors.lastname: Smith
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001861:Bone Regeneration / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects* / Q000378:metabolism; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D007150:Immunohistochemistry; D007783:Lactones / Q000494:pharmacology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D011817:Rabbits; D013450:Sulfones / Q000494:pharmacology*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007783:Lactones; D013450:Sulfones; C116926:rofecoxib; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases