Early recovery patterns differ between medially congruent and posterior-stabilized total knee arthroplasty, with comparable 2-year outcomes: A triple-blinded randomized clinical trial.

Study Summary

86 patients with advanced knee osteoarthritis were randomized to receive medially congruent (MC) or posterior-stabilized (PS) total knee arthroplasty (TKA), with 82 patients completing follow-up. The primary outcome of interest was the Knee injury and Osteoarthritis Outcome Score–Activities of Daily Living (KOOS-ADL). Secondary outcomes included range of motion (ROM), pain assessed using the visual analogue scale (VAS), joint awareness assessed using the Forgotten Joint Score-12 (FJS-12), patient satisfaction, complications, and coronal alignment. Outcomes were assessed at 2 weeks, 6 weeks, 3 months, 1 year, and 2 years. Overall, the results of the study revealed that MC-TKA provided greater early knee flexion, whereas PS-TKA resulted in less early postoperative pain and greater flexion at later follow-up. Although MC-TKA demonstrated statistically better KOOS-ADL and FJS-12 scores at 1 and 2 years, these differences did not exceed minimum clinically important difference (MCID) thresholds. These findings suggested that both implant designs provided comparable clinically meaningful functional recovery at 2 years despite differences in recovery patterns.