Hindawi Publishing Corporation Te Scientifc World Journal Volume 2013, Article ID 573526, 4 pages http://dx.doi.org/10.1155/2013/573526 Research Article The Influence of Storage Temperature on the Antibiotic Release of Vancomycin-Loaded Polymethylmethacrylate Dave W. Chen, 1 Yuhan Chang, 1 Pang-Hsin Hsieh, 1 Steve W. N. Ueng, 1,2 and Mel S. Lee 1,2,3 1 Department of Orthopaedic Surgery, Linkou Chang Gung Memorial Hospital, Taiwan 2 Department of Orthopaedic Surgery, Chia Yi Chang Gung Memorial Hospital, Taiwan 3 Department of Medicine, College of Medicine, Chang Gung University, 6 West Sec. Chiapu Road, Putzu City, Chia Yi Hsien, Taiwan Correspondence should be addressed to Mel S. Lee; mellee@adm.cgmh.org.tw Received 5 July 2013; Accepted 25 July 2013 Academic Editors: A. P. Kypson and Y. K. Tu Copyright © 2013 Dave W. Chen et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Periprosthetic joint infection is devastating and increases medical expenditure and socioeconomic burden. Antibiotic-loaded cement spacer is useful in the interim period before the reimplantation surgery. Prefabricated antibiotic-loaded cement spacers can decrease operation time but have been limitedly used clinically. In the literature, there is no clear recommendation on the storage temperature for the prefabricated cement spacers. We used an in vitro model to analyze whether the storage temperature at 25 ∘ C, 4 ∘ C, or −20 ∘ C for 2 weeks or 3 months could afect the release of vancomycin from the cement. We found that the storage temperature and time had no signifcant efects on the pattern and amount of vancomycin release. Te patterns of vancomycin release from the cement stored at diferent temperatures were similar with an abrupt release in the frst 3 days and steadily declined in the following period. Tis study provides a preliminary result to justify the storage of fabricating antibiotic-loaded cement spacer sterilely packed at room temperature. Further studies to examine the efects of storage temperature on the mechanical strength and the release pattern of other antibiotics should be done to provide more evidence to support the clinical use of prefabricated ready- to-use antibiotic-loaded cement spacer. 1. Introduction Periprosthetic joint infection (PJI) is a devastating condition that increases medical expenditure and patient’s economic burden [1, 2]. For established PJI, the most accepted treatment modality is a two-stage reimplantation protocol [2]. During the interim period before reimplantation, antibiotic-loaded cement spacer has been widely adopted as an efective method to deliver high levels of local antibiotics for infection control and to maintain the sof tissue tension before the reimplantation surgery [3]. Antibiotic-loaded cement spacer is usually manufactured by surgeons during operation. Tis can be time consuming. If the causing bacteria are known preoperatively, the antibiotic-loaded cement spacer can be fabricated in advance. Prefabricated antibiotic-loaded cement spacer is appealing because it not only reduces operation time but also decreases blood loss [4–6]. Hailey et al. reported that the mechanical properties of bone cement stored at 37 ∘ C were more brittle than those stored at 21 ∘ C[7]. However, in the literature, there is no recommendation for the storage of antibiotic-loaded cement spacer. In our previous study, we found that the antibacterial activity of antibiotics in the bone cement could be maintained at −80 ∘ C[8]. But it is impractical to store and ship the cement spacer at −80 ∘ C in common clinical settings. We hypothesized that the storage temperatures of antibiotic-loaded cement had no signifcant infuence on the antibiotic release. We tested our hypothesis by choosing room temperature (25 ∘ C), refrigerator (4 ∘ C), and freezer (−20 ∘ C) as the storage conditions by in vitro antibiotic release analysis. 2. Materials and Methods Vancomycin 8 g (Gentle Pharmaceutical Co, Yunlin, Taiwan) was thoroughly mixed with 40 g of Surgical Simplex bone cement powder (Stryker Orthopaedics, Limerick, Ireland) in a stainless-steel container prior to the addition of the liquid monomer. Afer mixing with liquid monomer for 2 min with