Reduced patellofemoral and walking pain with mobile-bearing vs. fixed-bearing total kneereplacements: a mid-term prospective analytic study

Objective: Total knee replacement (TKR) is the standard treatment for advanced stage knee osteoarthritis. The introduction of the mobile-bearing (MB) design has given rise to a series of theoretical advantages compared to fixed-bearing (FB) implants, although current literature does not reveal significant differences between the designs. The aim of this study was to estimate the clinical results of 2 cemented total knee prosthetic designs: an MB and an FB design. Methods: A series of patients with similar clinical and radiographic characteristics were treated consecutively with 100 FB followed by 94 MB implants. Patients were evaluated radiographically and clinically. Results: Statistically significant differences were found in terms of pain at 5 years in favor of MB prostheses (p=0.006). The “pain on ascending/descending stairs” category on the KSS score showed improvement at 5 years for the MB design (p=0.003). MB implants showed better results in terms of ability to ascend/descend stairs at five years (p=0.002). With regards to the patients’ ability to walk, there were differences at 1 year (p=0.020) and at 5 years (p=0.021) in favor of MB implants. Conclusion: At a mean follow-up of 5 years, significant differences were observed in the MB prosthesis in terms of postoperative pain, ability to ascend/descend stairs, and patellofemoral pain.