title: Whole body vibration during fracture healing intensifies the effects of estradiol and raloxifene in estrogen-deficient rats.
abstract: Current osteoporosis therapies aim to delay bone destruction and have additional anabolic effects. While they have demonstrated some positive effects on bone healing, more progress is needed in this area. This study used the well-known osteoporotic agents estrogen (E) and raloxifene (R) in conjunction with biomechanical whole body vibration (WBV) at a frequency of 70 Hz twice daily for six weeks to stimulate bone healing. Eighty-four 3-month old female Sprague-Dawley rats (12 per group) were bilaterally ovariectomized to develop osteopenia within eight weeks. Osteotomy of the metaphyseal tibiae was performed and fracture healing was then studied using mechanical tests, histomorphometry, computed tomography (μCT), and gene analysis. We found that E and R improved the structure of osteopenic bones as did WBV alone, although significant levels for WBV were seldom reached. Combination treatments significantly enhanced stiffness (R+WBV; p<0.05), endosteal bone (R+WBV; p<0.01), and trabecular density (E+WBV; p<0.05, R+WBV; p<0.05). In addition, the expression of osteoclast-specific Trap was significantly reduced after treatment with E, R, or their combination with WBV (p<0.01). The effects were additive and not inhibitory, leading us to conclude that the combined applications of WBV with E or R may improve the healing of osteopenic bones. The therapies studied are all currently approved for human use, suggesting ready applicability to clinical practice. To better understand the effects of WBV on osteopenic bones, the ideal vibration regime will require further study.
authors.affiliation: Institute for Research in Operative Medicine, Faculty of Health, School of Medicine, Witten/Herdecke University, Cologne, Germany; Department of Trauma Surgery and Reconstructive Surgery, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany. Electronic address: ewa.stuermer@uni.wh.de.
authors.forename: Ewa K
authors.initials: EK
authors.lastname: Stuermer
authors.affiliation: Department of Trauma Surgery and Reconstructive Surgery, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany.
authors.forename: Marina
authors.initials: M
authors.lastname: Komrakova
authors.affiliation: Department of Trauma Surgery and Reconstructive Surgery, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Sehmisch
authors.affiliation: Department of Trauma Surgery and Reconstructive Surgery, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Tezval
authors.affiliation: Department of Radiology, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Dullin
authors.affiliation: Institute for Research in Operative Medicine, Faculty of Health, School of Medicine, Witten/Herdecke University, Cologne, Germany.
authors.forename: Nadine
authors.initials: N
authors.lastname: Schaefer
authors.affiliation: Department of Trauma Surgery and Reconstructive Surgery, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Hallecker
authors.affiliation: Department of Trauma Surgery and Reconstructive Surgery, University of Goettingen, Robert-Koch 40, 37075 Goettingen, Germany.
authors.forename: Klaus M
authors.initials: KM
authors.lastname: Stuermer
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000494:pharmacology*; D004958:Estradiol / Q000494:pharmacology*; D004967:Estrogens / Q000172:deficiency*; D005247:Feeding Behavior / Q000187:drug effects; D005260:Female; D017102:Fracture Healing; D015870:Gene Expression / Q000187:drug effects; D009929:Organ Size / Q000187:drug effects; D020849:Raloxifene Hydrochloride / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014732:Vibration; D055114:X-Ray Microtomography
chemical_list: D050071:Bone Density Conservation Agents; D004967:Estrogens; D020849:Raloxifene Hydrochloride; D004958:Estradiol
keywords: Estrogens; Fracture healing; Osteoporosis; Raloxifene; Whole body vibration