Pressurized Carbon Dioxide Lavage Reduces the Incidence of a Radiolucent Line Around the Tibial Component Two Years After Total Knee Arthroplasty

Introduction: In cemented total knee arthroplasty (TKA), pressurized carbon dioxide (CO2) lavage prior to cement fixation can eliminate debris at the bone-cement interface and is considered effective for increasing cement penetration and preventing aseptic loosening. Regarding the risk of a preliminary diagnosis of implant loosening, a radiolucent line (RLL) is a valuable sign. The purpose of this study was to compare the incidence of a tibial RLL at 2 years after TKA with and without pressurized CO2 lavage.Methods: This is a retrospective study. One hundred knees from 98 patients were enrolled in this study. TKA was performed without pressurized CO2 lavage (CO2- group) for the first 47 knees, and with pressurized CO2 lavage (CO2+ group) for the next 53 knees. The depth of cement penetration was measured just after surgery, and the incidence of tibial RLL >2 mm, at 2 years after TKA was determined. Results: Significant differences between groups were not seen regarding pre- and postoperative clinical factors. The depth of cement penetration in each area was significantly higher in the CO2+ group. The frequency of knees with RLL >2 mm was significantly lower in the CO2+ group than in the CO2- group (p<0.001).Conclusions: Pressurized CO2 lavage improved cement penetration and decreased the incidence of tibial RLL >2 mm at 2 years after TKA. Since the RLL has been reported as a valuable sign for preliminary diagnosis of loosening, pressurized CO2 lavage appears effective for preventing loosening.