Clinical features of patients with rheumatoid arthritis requiring knee and hip arthroplasty depending on disease activity

Background: Total arthroplasty (TA) is a surgical procedure that can significantly improve the condition of patients with rheumatoid arthritis (RA) at the terminal stage of joint damage. According to existing recommendations, in order to improve the long-term functional outcome and reduce the risk of complications, TA is advisable to be performed upon achieving remission/low disease activity (LDA) of RA. However, in real clinical practice, TA is often performed in patients with moderate RA activity.

Objective: Evaluation of the activity and main clinical manifestations of RA in patients requiring TA of the knee or hip joints in real clinical practice.

Materials and methods: The study group consisted of 158 patients with RA, 81.6% women, mean age 57.2±13.2 years, DAS28-CRP 3.6±1.0, who underwent total knee arthroplasty (TKA) – 69.8%, or total hip arthroplasty (THA) – 30.2% in the Traumatology and Orthopedics Department of the V.A. Nasonova Research Institute of Rheumatology in 2023–2024. Patients were divided into 2 groups. Group 1 included patients who achieved remission/LDA – 44 (27.8%), group 2 – patients with moderate RA activity – 114 (72.2%). An assessment of disease activity (DAS28, SDAI and CDAI), functional impairment (Harris, KSS, HAQ), neuropathic descriptors (PainDETECT questionnaire), signs of central sensitization (CSI scale), fibromyalgia (FiRST questionnaire), depression and anxiety (HADS scale), fatigue (FSS questionnaire) was performed.

Results: Patients in group 1 were younger than those in group 2: mean age 53.45±14.72 and 58.53±12.41 years (p=0.032), less frequently seropositive for RF – 72.1 and 89.4% (p=0.012), but not for ACPA – 57.5 and 71.1% (p=0.09), had a significantly lower number of painful and swollen joints out – 28 and 66, better patient and physician health assessment, lower ESR – 8.05±7.47 and 33.14±26.36 mm/hour (p<0.001), and lower CRP level – 3.66±8.22 and 11.21±13.73 mg/l (p=0.013). The DAS28-CRP value was 2.66±0.67 and 3.68±0.71, SDAI – 10.69±3.47 and 16.33±5.21, CDAI – 10.45±3.28 and 14.59±4.90 (all indicators – p<0.001), HAQ – 1.31±0.69 and 1.67±0.77 (p=0.014). At the same time, no significant differences in pain intensity (NRS 0-10) – 5.14±2.79 and 5.75±2.16 (p=0.155), Harris and KSS scales, PainDETECT questionnaire, CSI and HADS scales, presence of fibromyalgia and fatigue severity (FSS) were found in the study groups. Patients of groups 1 and 2 equally often used synthetic DMARDs – 79.5 and 76.7% (p=0.833), glucocorticoids – 58.5 and 56.6% (p=0.858). biologic DMARDs were used significantly more often in group 1: 40.9 and 17.5% (p=0.003). In groups 1 and 2, one serious perioperative complication was noted – instability of the endoprosthesis.

Conclusion: Most patients with RA who underwent knee or hip arthroplasty had moderate inflammatory activity. The severity of pain, fatigue, signs of nociceptive system dysfunction and psychoemotional disorders in these patients did not depend on the activity of RA. The use of biologic agents was associated with the achievement of remission/LDA in patients with RA who required TA.