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Background: Ceftaroline is a cephalosporin that is effective against methicillin-resistant Staphylococcus aureus (MRSA) infections. The objective of this study was to determine the feasibility of using ceftaroline-loaded Polymethyl methacrylate (PMMA) as antibiotic cement against MRSA versus vancomycin-loaded PMMA in an in vitro setting. Methods: PMMA pellets were prepared with three separate concentrations of each of the two antibiotics tested. They were tested to determine the effect of increasing concentration of antibiotics on the biomechanical properties of PMMA and antibiotic activity by measuring the zone of inhibition and broth elution assay. Results: Ceftaroline PMMA at 3 wt%, three-point bending was 37.17 + 0.51 N (p < 0.001) and axial loading was 41.95 N + 0.51 (p < 0.001). At 5-wt% vancomycin-PMMA, three-point bending was 41.65 + 0.79 N (p ¼ 0.02) and axial loading was 49.49 + 2.21 N (p ¼ 0.01). Stiffness of ceftroline-loaded PMMA in low and medium concentration was significantly higher than the vancomycin. The zone of inhibition for ceftaroline was higher than vancomycin. Ceftaroline at 3 wt% eluted up to 6 weeks (0.3 + 0.1 mg/ml) above the minimum inhibitory concentration (MIC) and vancomycin at 2.5 wt% eluted up to 3 weeks, same as MIC, that is, 0.5 + 0.0 mg/ml. Conclusions: Ceftaroline, loaded at similar concentrations as vancomycin into PMMA, is a more potent alternative based on its more favourable bioactivity and elution properties, while having a lesser effect on the mechanical properties of the cement. The use of 3-wt% ceftaroline as antibiotic laden PMMA against MRSA is recommended. It should be noted that this was an in vitro study and to determine the clinical efficacy would need prospective, controlled and randomized studies.

Cannulated screw fixation is a widely accepted surgical method for management of fractures of the neck of femur especially in patients with poor premorbid conditions, minimally displaced fractures and those from a younger age group. A five year retrospective study was carried out in 53 consecutive patients between 2006 to 2010 to determine the pattern of injuries, management, outcomes and the associated predictive factors.All the patients underwent cannulated screw fixation, with 37 (69.8%) having had surgery within 24 hours and the remaining 16 (30.2%) 24 hours after the initial injury. All patients were followed up to union of fractures and complications thereafter if any. Good outcome was observed in 43 (81.1%) patients leaving only 10 (18.9%) patients with a poor outcome, of whom nine developed avascular necrosis (90%) and one non-union (10%). We found no significant relationship between the incidence of avascular necrosis and age of patient, fracture displacement, numbers of cannulated screws used, fracture reduction acceptability and anatomical location of the fracture. The time interval from injury to surgery and the presence of posterior comminution did seem to influence the rate of avascular necrosis but due to the small number of patients, was not statistically significant.We conclude that cannulated screw fixation is a viable option of treatment for fractures of the neck of femur.Key Wordsfemoral neck fractures, screw fixation

Chondroblastomas are a primary benign cartilaginous tumor that accounts for approximately 1% of all benign bone tumors. Primarily they are treated by curettage. The patient presented 4 years after a successfully treated chondroblastoma (curettage and Bone cement). Wide resection of the proximal tibia with endoprosthesis replacement was done. Lung CT showed multiple lung metastasis and despite starting chemotherapy, he succumbed to the disease. We discuss regarding the possibilities of “aggressive” chondroblastoma and more recently termed chondroblastoma-like osteosarcoma which is a separate entity from chondroblastoma. Aggressiveness in chondroblastoma can be 1 of 3 types as follows: 1. benign chondroblastoma with lung metastasis. 2. malignant chondroblastoma. 3. subsequent malignant transformation of benign chondroblastoma. We have attempted to review the literature and describe the “aggressive” chondroblastoma and chondroblastoma-like osteosarcoma in this report.

Arthroplasty-related infection has grown worldwide. Revision procedures for infection are associated with longer operating time, superior amounts of blood loss, and substantial economic encumbrance. To overcome cost, many surgeons opt for hand-mixed vancomycin into the bone cement. The objective of this research was to assess the biomechanical strength and antibacterial properties of hand-mixed vancomycin bone cement at different concentrations with commonly used industrial preblended antibiotic bone cement and plain cement. The target was to determine the ideal concentration of antibiotics that can be used in the preparation of hand-mixed vancomycin cement that delivers maximum antibiotics concentration without compromising its biomechanical properties. Materials and Methods: Vancomycinimpregnated polymethyl methacrylate (PMMA) specimen was hand prepared in varying concentrations (1-4 g). The authors tested three-point bending strength to determine 'maximum bending load' and stiffness and its antibacterial activity by looking into the zone of inhibition on methicillin-resistant Staphylococcus aureus-impregnated agar plate. These were compared with the industrial preblended Simplex™ P with 1 g tobramycin. Results: This study exhibited that vancomycin-PMMA disk that contained higher concentration of antibiotics had significantly higher antibacterial activity. The control group (plain cement) and industrial PMMA with preblended antibiotic (tobramycin) showed stable mechanical strength, while the hand-mixed antibiotic cement (HMAC) had variable mechanical strength varying on the concentration of antibiotics used. Conclusion: It was effectively concluded that HMAC is advantageous as a cement spacer; however, it is not recommended for primary arthroplasty and second-stage revision arthroplasty. The recommended maximum concentration of vancomycin based on this study is 2 g/pack (40 g) of cement. Industrial preblended antibiotic cement is superior to hand-mixed cement.