title: The effect of a biphasic injectable bone substitute on the interface strength in a rabbit knee prosthesis model.
abstract: BACKGROUND
  In joint prosthetic surgery, various methods are used to provide implant stability. We used an injectable bone substitute, composed of calcium sulfate/hydroxyapatite, as bone defect filler to stabilize a tibia prosthesis in an experimental rabbit model. The aim of the study was to investigate and compare the stability of prosthetic fixation with and without the use of an injectable bone substitute.
  
  
  METHODS
  Sixteen rabbits were used and the tibia prostheses were implanted bilaterally, one side with the prosthesis alone and the other side with the prosthesis and calcium sulfate/hydroxyapatite (Cerament™). The rabbits were randomly divided into two groups and euthanized after 6 and 12 weeks, respectively. The prosthesis was extracted measuring the pull-out force in an Instron tester, and the bone surrounding the former prosthesis site was analyzed by histology, histomorphometry, and micro-computed tomography.
  
  
  RESULTS
  At 6 weeks no difference in maximum pull-out force was found between the prostheses fixed with or without Cerament™. At 12 weeks the maximum pull-out force for the prostheses with Cerament™ was significantly higher than that for the prostheses without Cerament™ (p = 0.04). The maximum pull-out force at 12 weeks was significantly higher than that at 6 weeks for the prostheses fixed with Cerament™ (p = 0.03) but not for the prostheses without.
  
  
  CONCLUSIONS
  We conclude that early prosthesis-bone interface strength is not influenced by a bone substitute. However, during remodeling, the bone substitute might provide improved mechanical support for the prosthesis. The results support further studies of the use of injectable calcium sulfate/hydroxyapatite in fixation of prosthetic joint implants.
authors.affiliation: Department of Orthopedics, Clinical Sciences, Lund University, Lund, Sweden. Vasileios.Zampelis@med.lu.se
authors.forename: Vasilis
authors.initials: V
authors.lastname: Zampelis
authors.forename: Magnus
authors.initials: M
authors.lastname: Tägil
authors.forename: Lars
authors.initials: L
authors.lastname: Lidgren
authors.forename: Hanna
authors.initials: H
authors.lastname: Isaksson
authors.forename: Isam
authors.initials: I
authors.lastname: Atroshi
authors.forename: Jian-Sheng
authors.initials: JS
authors.lastname: Wang
mesh_terms: D000818:Animals; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D018786:Bone Substitutes / Q000008:administration & dosage / Q000627:therapeutic use*; D002133:Calcium Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D020878:Device Removal; D004195:Disease Models, Animal; D004338:Drug Combinations; D017886:Durapatite / Q000008:administration & dosage / Q000627:therapeutic use*; D007270:Injections, Intra-Articular; D007720:Knee Prosthesis; D008422:Materials Testing / Q000379:methods; D011475:Prosthesis Failure; D011817:Rabbits; D013314:Stress, Mechanical; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D018786:Bone Substitutes; D004338:Drug Combinations; C582328:cerament; D017886:Durapatite; D002133:Calcium Sulfate
references.citation: J Bone Joint Surg Br. 2004 Jan;86(1):120-5
references.pmid: 14765879
references.citation: Orthopedics. 2004 Jan;27(1 Suppl):s103-7
references.pmid: 14763538
references.citation: Int Orthop. 2011 Feb;35(2):267-73
references.pmid: 21165618
references.citation: J Biomed Mater Res. 1999 Jan;44(1):31-43
references.pmid: 10397902
references.citation: Arch Orthop Trauma Surg. 1998;117(3):170-2
references.pmid: 9521525
references.citation: Curr Mol Pharmacol. 2012 Jun;5(2):153-63
references.pmid: 21787290
references.citation: Acta Orthop. 2011 Apr;82(2):136-42
references.pmid: 21434792
references.citation: Eur Spine J. 2012 May;21 Suppl 1:S112-8
references.pmid: 22434530
references.citation: J Bone Joint Surg Br. 2006 Aug;88(8):993-6
references.pmid: 16877594
references.citation: Clin Orthop Relat Res. 1994 Jul;(304):272-9
references.pmid: 8020228
references.citation: J Biomed Mater Res. 2002 Sep 15;61(4):600-7
references.pmid: 12115450
references.citation: Acta Orthop Scand Suppl. 2000 Feb;290:1-40
references.pmid: 10745934
references.citation: Acta Orthop Scand. 2003 Aug;74(4):483-9
references.pmid: 14521303
references.citation: J Biomed Mater Res B Appl Biomater. 2010 Jan;92(1):281-6
references.pmid: 19904822
references.citation: Acta Orthop. 2006 Feb;77(1):39-48
references.pmid: 16534701
references.citation: Clin Orthop Relat Res. 2000 Sep;(378):274-81
references.pmid: 10987003
references.citation: Interv Neuroradiol. 2012 Mar;18(1):105-13
references.pmid: 22440608
references.citation: J Orthop Res. 2004 Sep;22(5):1008-15
references.pmid: 15304273
references.citation: Orthop Clin North Am. 2005 Jan;36(1):89-95, vii
references.pmid: 15542127