Influence of the infrapatellar fat pad resection in a synovectomy during total knee arthroplasty (TKA) was evaluated in patients with rheumatoid arthritis (RA). Our findings for 120 RA patients at 28 to 38 months after surgery showed that (i) a significant decrease in the number of patients with anterior aching discomfort despite a lower-lying patella was seen in patients with infrapatellar synovectomy compared with patients without infrapatellar synovectomy, and (ii) an increase in the number of patients with anterior aching discomfort, significant limited motion, slight quadriceps weakness, and significant shortening of patellar tendon length and patella height were noted among patients with infrapatellar synovectomy, including fat pad resection, than in patients without infrapatellar synovectomy.