Cemented versus Uncemented Partial Knee Arthroplasty Trial – The CUPKAT Trial – A prospective, randomized controlled trial
BackgroundCemented Oxford unicompartmental knee arthroplasty (OUKA) has shown excellent clinical and functional long-term results as a treatment option for patients with end-stage anteromedial osteoarthritis of the knee. Despite the good long-term results that have been reported in the literature, registry data show that aseptic loosening and pain associated with the appearance of commonly seen radiolucencies around the tibial component are the most common causes for revision surgery in
... OUKA. In order to address these problems, the cementless OUKA has been developed. Initial studies indicate excellent clinical short-term results for cementless OUKA although the risk of tibial head fracture seems to be elevated and long-term results are not yet available. Given the ongoing debate about the benefits or disadvantages of cementless fixation in knee arthroplasty, there is a need for independent level I and level II studies in order to assess the safety and equivalence of cementless OUKA in comparison to the well-documented clinical results of the cemented OUKA.Methods/DesignThis study has a prospective, randomized, controlled, double-centre, non-inferiority design. A total of 306 Patients with anteromedial OA will be randomized to cementless or cemented OUKA either at the Heidelberg University Hospital or at the Kepler University Hospital Linz. As primary outcome measure we evaluate the Oxford Knee Score (OKS) to compare clinical and functional results 2 years after cemented versus uncemented OUKA.Secondary outcome measures include clinical and functional scores as measured with the American Knee Society Score (AKSS), UCLA Activity Score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Forgotten Knee Score (FJS-12), Visual Analog Pain Score (VAS), and health related quality of life questionaire (EQ-5D). In addition, complications such as the occurrence of periprosthetic fractures or implant loosening, incidence of radiolucencies and reoperation rates among others will be evaluated as secondary outcome measures and compared between the two groups. A subgroup of patients (n=150) will be asked to undergo additional radiographic DXA measurement to assess the changes in bone mineral density around the femoral and tibial components preoperatively and two years after surgery.Trials RegistrationPrior to the beginning of the clinical phase (FPI) we registered the trial at Deutsches Register Klinischer Studien (German Clinical Trials Register) with the registration number: DRKS00021303. Registered 30 April 2020. The Registration will be forwarded to the to the WHO within the next update (within the next 4 weeks) and will be searchable via its Meta-registry ( http://apps.who.int/trialsearch/ ).