To undertake a biomechanical study to determine the existence of any difference in the early tibial component fixation to bone, between two widely used techniques of cementation, which may confer an influence on implant survival. 20 tibial saw bones were prepared by standard methods using extramedullary instrumentation to receive a fixed bearingtibial component (PFC, DePuy). Under controlled laboratory conditions, thetibial trayswere implanted with CMW cement using either of the two following cementation techniques (10 implants in each group): Full cementation–application of cement to the undersurface of the tibial tray, the keel, the cut surface of the tibia and its stem hole. Surface cementation – application of cement only to the undersurface of thetibial tray and the cut surface of the tibia. 72 hours after implantation, the fixation of the cemented components was assessed by determining the load to failure under controlled tensile stresses (using an Instron Electro-mechanical tensile tester).Aim
Method
Research undertaken at Wrightington has shown that in primary joint replacement coagulase-negative staphylococci account for 67.2% – 76% of contaminants isolated from the ultra clean zone. It is the most prevalent and persistent species on human skin and mucous membranes and accounts for 58% of failures due to deep infection of primary THR. Further studies of nosocomial infection transmission show bacterial contamination of healthcare workers’ scissors, ballpoint pens, stethoscopes and lab coats with MRSA, VRE and gram-negative bacilli. Multiuse skin markers may become colonised, possibly with MRSA, MRSE and gram-negative bacilli. This may contaminate patients and cause premature failure of arthroplasty, leading some units to adopt a single use policy. Our aim was to ascertain bacterial colonisation of multiuse skin markers.
Pens identified by a number, brand, location and approximate pen age. Pen tips were neutralised with 10ml sterile Peptone water and this was used as the inoculum. Cap interior swabbed with sterile swab (pre-dipped in sterile water). Both were inoculated into enrichment broth and plated onto Blood and McConkey media. Incubation at 37°c for 18 hours with plates read at 7 days for colony forming units.
No growth on all plates after incubation for 7 days.
