Local and systemic inflammatory responses in conventional manual versus robotic-arm-assisted total knee arthroplasty: a prospective comparative study

This study aimed to compare local and systemic inflammatory responses between conventional total knee arthroplasty (C-TKA) and robotic-arm–assisted TKA (R-TKA), which is proposed to reduce surgical trauma and inflammation. This prospective study included 60 patients (34 C-TKA and 26 R-TKA) who underwent primary TKA. Local inflammation was evaluated by analyzing tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 in drain fluid obtained at 6, 24, and 48 h postoperatively. Blood samples were collected preoperatively and at 6 h and on postoperative days (POD) 1, 2, 7, 14, 30, and 60. Systemic markers included white blood cell (WBC) counts, differential counts, neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), creatine kinase (CK), lactate dehydrogenase (LDH), TNF-α, IL-6, and IL-8. Local joint inflammatory markers were significantly lower in the R-TKA group compared to the C-TKA group, with lower IL-8 on POD 1 ( P = 0.017) and POD 2 ( P < 0.001), along with lower TNF-α on POD 2 ( P = 0.015). Systemically, serum IL-6 was lower in the R-TKA group at 6 h and on POD 1, 2, and 30 (all P < 0.05). Serum IL-8 and TNF-α were lower in the R-TKA group at 6 h and on POD 1, with IL-8 also lower on POD 2 (all P < 0.05). CRP was lower in the R-TKA group on POD 2, 7, 14, and 30 (all P < 0.05). LDH was lower on POD 7 and 14 (all P < 0.05). WBC counts were lower at 6 h and on POD 2, 7, 14, and 30 (all P < 0.05). Neutrophil counts were lower at 6 h and from POD 7 to 60, and monocyte counts were lower from 6 h to POD 60 in the R-TKA group (all P < 0.05). R-TKA was associated with lower local and systemic inflammatory responses compared to C-TKA.