Comparison of the Complications of Knee Replacement Using Fixed or Mobile Inserts

BACKGROUND/AIMS: Knee replacement surgery or total knee arthroplasty is a widely performed procedure to alleviate pain and improve function in patients with severe knee joint degeneration or injury.The choice between fixed and mobile inserts for knee replacement implants remains critical.Fixed-bearing implants provide stability, whereas mobile-bearing implants offer increased conformity and potential for improved range of motion.This study aimed to compare the complications of knee replacement using fixed and mobile inserts. MATERIALS AND METHODS:A retrospective analysis was conducted on 412 knee replacement patients who underwent surgery between 2011 and 2021 using either the Smith & Nephew GENESIS-II fixed insert knee prosthesis or Zimmer-Mobile insert knee prosthesis.Data collection involved rigorous evaluation of patient files, radiographs, and postoperative outcomes.Data on age, gender, side of the knee prosthesis, preoperative and postoperative tibiofemoral angle, proximal tibia angle, osteolysis around the prosthesis, and complications, such as instability, infection, extensor mechanism problems, aseptic loosening, and radiological osteolysis, were recorded.Complications requiring surgical intervention were also noted. RESULTS:The mean age of patients was 65.18 years, and 88.5% were female.The mobile insert group included younger patients with a higher incidence of bilateral knee arthroplasties.Radiological evaluation revealed a higher incidence of patella changes and subsequent patella replacement in the mobile insert group.However, the overall complication rate was not significantly different between the two groups.Although postoperative joint alignment did not significantly differ between the groups, the postoperative proximal tibial angles were higher in the mobile insert group.Specific complications, including instability, infection, extensor mechanism problems, aseptic loosening, and radiological osteolysis, did not significantly differ between the two groups. CONCLUSION:The choice of fixed or mobile insert during knee replacement did not significantly affect the incidence of specific complications.Surgeons should consider individual patient factors, surgeon preference, and technical expertise when selecting the appropriate implant type for knee replacement surgery.