MATERIALS AND METHODS: Twenty nine operations for skeletal metastasis of the femur performed in our centre between 2009 and 2015 were included in this study. We evaluated the choice of implant, complications, survival rate and functional outcome. Fourteen patients were still alive at the time of this report for assessment of functional outcome using Musculoskeletal Tumour Society (MSTS) form.
RESULTS: Plating osteosynthesis with augmented-bone cement was the most common surgical procedure (17 patients) performed followed by arthroplasty (10 patients) and intramedullary nailing (2 patients) There were a total of five complications which were implant failures (2 patients), surgical site infection (2 patients), and site infection mortality (1 patient). The median survival rate was eight months. For the functional outcome, the mean MSTS score was 66%.
CONCLUSION: Patients with skeletal metastasis may have prolonged survival and should undergo skeletal reconstruction to reduce morbidity and improve quality of life. The surgical construct should be stable and outlast the patient to avoid further surgery.
METHODS: Vancomycin at various concentrations was added to JectOS and polymethyl methacrylate (PMMA). Then, the cement was molded into standardized dimensions for in vitro testing. Cylindrical vancomycin-JectOS samples were subjected to compressive strength. The results obtained were compared to PMMA-vancomycin compressive strength data attained from historical controls. The zone of inhibition was carried out using vancomycin-JectOS and vancomycin-PMMA disk on methicillin-resistant strain culture agar.
RESULTS: With the addition of 2.5%, 5%, and 10% vancomycin, the average compressive strengths reduced to 8.01 ± 0.95 MPa (24.6%), 7.52 ± 0.71 MPa (29.2%), and 7.23 ± 1.34 MPa (31.9%). Addition of vancomycin significantly weakened biomechanical properties of JectOS, but there was no significant difference in the compressive strength at increasing concentrations. The average diameters of zone of inhibition for JectOS-vancomycin were 24.7 ± 1.44 (2.5%) mm, 25.9 ± 0.85 mm (5%), and 26.8 ± 1.81 mm (10%), which outperformed PMMA.
CONCLUSION: JectOS has poor mechanical performance but superior elution property. JectOS-vancomycin cement is suitable as a void filler delivering high local concentration of vancomycin. We recommended using it for contained bone defects that do not require mechanical strength.