title: A comparison of commercially available demineralized bone matrices with and without human mesenchymal stem cells in a rodent spinal fusion model.
abstract: OBJECTIVE The efficacy of some demineralized bone matrix (DBM) substances has been demonstrated in the spinal fusion of rats; however, no previous comparative study has reported the efficacy of DBM with human mesenchymal stem cells (hMSCs). There is an added cost to the products with stem cells, which should be justified by improved osteogenic potential. The purpose of this study is to prospectively compare the fusion rates of 3 different commercially available DBM substances, both with and without hMSCs. METHODS Posterolateral fusion was performed in 32 mature athymic nude rats. Three groups of 8 rats were implanted with 1 of 3 DBMs: Trinity Evolution (DBM with stem cells), Grafton (DBM without stem cells), or DBX (DBM without stem cells). A fourth group with no implanted material was used as a control group. Radiographs were obtained at 2, 4, and 8 weeks. The rats were euthanized at 8 weeks. Overall fusion was determined by manual palpation and micro-CT. RESULTS The fusion rates at 8 weeks on the radiographs for Trinity Evolution, Grafton, and DBX were 8 of 8 rats, 3 of 8 rats, and 5 of 8 rats, respectively. A significant difference was found between Trinity Evolution and Grafton (p = 0.01). The overall fusion rates as determined by micro-CT and manual palpation for Trinity Evolution, Grafton, and DBX were 4 of 8 rats, 3 of 8 rats, and 3 of 8 rats, respectively. The Trinity Evolution substance had the highest overall fusion rate, however no significant difference was found between groups. CONCLUSIONS The efficacies of these DBM substances are demonstrated; however, the advantage of DBM with hMSCs could not be found in terms of posterolateral fusion. When evaluating spinal fusion using DBM substances, CT analysis is necessary in order to not overestimate fusion.
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;|Department of Orthopaedic Surgery, Japan Labour Health and Welfare Organization, Spinal Injuries Center, Fukuoka, Japan;
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Lord
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;
authors.forename: Akinobu
authors.initials: A
authors.lastname: Suzuki
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;
authors.forename: Shinji
authors.initials: S
authors.lastname: Takahashi
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;
authors.forename: Trevor P
authors.initials: TP
authors.lastname: Scott
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;
authors.forename: Kevin
authors.initials: K
authors.lastname: Phan
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, California;
authors.forename: Haijun
authors.initials: H
authors.lastname: Tian
authors.affiliation: Department of Orthopaedic Surgery, University of Nevada, Las Vegas, Nevada; and.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Daubs
authors.affiliation: Department of Orthopaedic Surgery, Japan Labour Health and Welfare Organization, Spinal Injuries Center, Fukuoka, Japan;
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Shiba
authors.affiliation: Department of Orthopaedic Surgery, University of Southern California, Los Angeles, California.
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Wang
mesh_terms: D000818:Animals; D018786:Bone Substitutes; D016025:Bone Transplantation / Q000295:instrumentation; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D011923:Rats, Nude; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*; D013131:Spine / Q000000981:diagnostic imaging / Q000601:surgery; D016896:Treatment Outcome; D055114:X-Ray Microtomography
chemical_list: D018786:Bone Substitutes
keywords: DBM = demineralized bone matrix; athymic nude rats; demineralized bone matrix; fusion rate; hMSC = human mesenchymal stem cell; human mesenchymal stem cells; micro-CT; posterolateral fusion; spinal fusion