Content area
Full Text
Received Feb 26, 2018; Revised Apr 10, 2018; Accepted Apr 16, 2018
This 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.
1. Introduction
Periprosthetic joint infection after total joint arthroplasty is a serious complication that requires prompt treatment. The two-stage exchange procedure is an effective treatment option for such infections [1]. Intravenously administered antibiotics, such as vancomycin (VCM), have poor tissue transferability depending on the site of infection, which decreases their therapeutic potential [2]. The therapeutic potential of VCM can be improved by combining it with a carrier to increase its retention at infection sites in the first stage of the procedure [3].
Calcium phosphate cement (CPC) has good release efficiency and has therefore been used as a drug delivery system for postoperative infection. CPC can release a greater volume of antibiotic over a longer duration than polymethylmethacrylate (PMMA) cement [4–7], a finding that has also been confirmed clinically [8–10]. Antibiotic release from the cement material is triggered when external solvent penetrates the material’s pores, causing the antibiotic to diffuse out of the material [11, 12]. In vitro studies are carried out by immersing test specimens in a relatively large amount of solvent, thereby providing ideal conditions for antibiotic release. However, it is unclear whether such release also occurs in vivo because tissue fluid is expected to only fill a few implanted sites compared to in vitro studies in the field of orthopedic surgery.
Here, we implanted CPC impregnated with VCM into rat tissue between the fascia and muscle and evaluated the release profile in vivo. We also compared the release profiles in vitro.
2. Materials and Methods
2.1. Materials
CPC (Biopex-R Advance) and PMMA (Surgical Simplex P Bone Cement) were obtained from HOYA Technosurgical (Tokyo, Japan) and Stryker (Tokyo, Japan), respectively. Injectable VCM hydrochloride was purchased from Shionogi (Osaka, Japan). All other chemicals were obtained from Wako Pure Chemical Industries (Osaka, Japan).
2.2. Preparation of Test Specimens
All preparations were performed aseptically. CPC powder (24 g), VCM (2 g), and a dedicated solvent (5.6 mL) were uniformly mixed to make a paste before adding a further 1.6 mL of solvent for effective handling (final volume...