In Vitro Elution Characteristics of Vancomycin in a Composite Calcium Phosphate/Calcium Sulfate Bone Substitute
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Periprosthetic joint infection is a particularly difficult orthopedic problem, complicating a growing number of revision procedures. Joint debridement and systemic antibiotics are the mainstay of treatment, yet difficulty remains in maintaining a minimum inhibitory concentration of antibiotic at the localized site of infection.
This study analyzes the elution characteristics of a 40%bwt calcium phosphate–60%bwt calcium sulfate composite, at varying concentrations of vancomycin.
Four groups of varying concentrations of vancomycin (2.63%bwt, 5.13%, 9.76%, and 17.78%) were mixed with one pack of the composite cement. At designated time intervals up to 28 days, the antibiotic concentration was detected using fluorescence polarization immunoassay and the elution trends compared.
The elution rate of each of the four groups decreased over time. At almost all of the intervals, the elution rates of the higher concentration groups were significantly higher than the lower concentration groups (P < 0.05).
Calcium sulfate reabsorbs over a prolonged period, producing porosity which allows for new bone ingrowth through occupation of osteoprogenitor cells and osteoblasts; while calcium phosphate acts as a long-term osteoconductive matrix.
The results of this study suggest that vancomycin can be mixed affectively with a calcium sulfate/phosphate composite, both maintaining stability and eluting gradually over a clinically relevant period of time.
Keywordsantibiotic delivery drug delivery bone infection
- 1.Adams K, Couch L, Cierny G, Calhoun J, Mader JT. (1992) In vitro and in vivo evaluation of antibiotic diffusion from antibiotic-impregnated polymethylmethacrylate beads. Clin Orthop 8:244–52Google Scholar
- 6.Hernandez-Soria A, Yang X, Reinhart J, Ricciardi BF, Bostrom M. In vitro elution characteristics of antibiotic laden hydroxyapatite bone cement. Abstract 0924, 52nd Annual Meeting of the Orthopaedic Research SocietyGoogle Scholar
- 19.Rajzer I, Castaño O, Engel E, Planell JA. (2010) Injectable and fast resorbable calcium phosphate cement for body-setting bone grafts. J Mater Sci Mater Med.http://www.springerlink.com/content/p28rv2425154k524. Accessed 12th May 2010
- 24.Turner TM, Urban RM, Gitelis S, Kuo KN, Andersson GBJ. (2001) Radiographic and histologic assessment of calcium sulfate in experimental animal models and clinical use as a resorbable bone-graft substitute, a bone-graft expander, and a method for local antibiotic delivery: one institution’s experience. J Bone Joint Surg Am. 83(suppl 2):8–18.PubMedGoogle Scholar
- 26.Urban RM, Turner TM, Hall DJ, Infanger SI, Cheema N, Lim TH, Moseley J, Carroll M, Roark M. (2004) Effects of altered crystalline structure and increased initial compressive strength of calcium sulfate bone graft substitutes on new bone formation. Orthopedics. 27(1 suppl):S113–S118.PubMedGoogle Scholar