Document Type: RESEARCH PAPER
Taleghani Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Akhtar Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Shahid Beheshti University of Medical Sciences, Tehran, Iran
Background: Due to the obvious differences in the natural course of rheumatoid arthritis (RA) and osteoarthritis (OA),
different functional outcomes might be expected after Total Knee Arthroplasty (TKA) in these distinct patients. Although
several studies have reported the objective outcome of TKA in RA and OA patients, few studies have compared postoperative
Methods: In this clinical cohort study 171 patients (RA: n=33, OA: n=138) who underwent TKA with posterior
stabilizing knee prosthesis were included. The Knee Injury and Osteoarthritis Outcome Score (KOOS) and Oxford
Knee Score (OKS) were used to evaluate and compare patients’ satisfaction 6 and 12 months after TKA relative to
their preoperative state and to make an assessment between two groups.
Results: Both of patient-reported scoring systems showed a statistically significant improvement for OA and RA
patients at 6 and 12 months after surgery, relative to their preoperative scores. The results of the OKS and KOOS did
not show statistically significant improvement from 6 to 12 months n RA patients. Unlike RA group, OKS and KOOS
revealed further improvement between 6 and 12 months for the osteoarthritic patients.
Conclusion: OA patients had continuous improvement in their satisfaction in the first year after TKA with a gentle
upward curve. In contrast, in RA patients, recovery was faster and greater in the first six months after surgery and
slowed down in the second six months. Patient-reported outcome scores were not significantly different between two
groups at the end of the first year.
Level of evidence: II