Comparative outcomes of robot-assisted versus conventional TKA in rheumatoid arthritis patients

To evaluate the surgical outcomes of RA-TKA compared to C-TKA in patients with rheumatoid arthritis.

A retrospective study was conducted at the PLA General Hospital, enrolling 239 rheumatoid arthritis patients who underwent either robot-assisted TKA or conventional TKA, with 102 and 187 patients in the RA-TKA and C-TKA groups, respectively. All patients were followed up 2 years. Follow-up indicators included KSS and WOMAC scores, single-leg standing time(SLST), and knee joint range of motion. The patients were evaluated at 2 weeks, 3 months, 6 months, 1year and 2 years postoperatively. All data were prospectively collected.

At 2 weeks postoperatively, the RA-TKA group showed superior KSS symptom scores (9.23 ± 3.38 vs. 10.79 ±  2.67 p =  0.001) compared to the C-TKA group. Additionally, at 2 weeks, the RA-TKA group had better WOMAC total scores (30.85  ±  9.92 vs. 34.61± 13.47 p =  0.01), pain (6.06 ± 2.55 vs. 6.81 ±  2.83 p =  0.027), stiffness (2.62 ±  1.15 vs. 2.90 ± 0.99 p  =  0.037), and Physical function (22.17 ±  8.11 vs. 24.90 ± 12.34 p = 0.032). At 3 months postoperatively, the RA-TKA group outperformed the C-TKA group in WOMAC total scores (13.3 ±  7.43 vs. 17.56 ±  9.34 p= 0.000), Physical function (7.41 ± 5.69 vs. 12.1± 7.56 p=  0.000), and knee range of motion (109.68 ± 10.15 vs. 105.63  ± 9.59 p =  0.005). At 6 months postoperatively, the RA-TKA group had higher satisfaction scores (31.54 ±  5.34 vs. 28.56 ±  5.36 p = 0.000). There were no significant differences in postoperative complications between the two groups.

RA-TKA can achieve better early outcomes in patients with rheumatoid arthritis, facilitating early rehabilitation. This provides important evidence for selecting surgical methods in rheumatoid osteoarthritis.