[Comparative study of total knee arthroplasty assisted by robot and remote sensing navigation system]

To compare clinical efficacy of robot-assisted (RA) and remote sensing navigation alignment (RSNA) system-assisted total knee arthroplasty (TKA).

From March 2023 to June 2023, 60 patients who underwent the first unilateral TKA due to severe knee osteoarthritis (KOA) were admitted and divided into RSNA group and RA group according to different treatment methods, with 30 patients in each group. There were 5 males and 25 females in RSNA group, aged from 56 to 81 years old with an average of(66.33±7.16) years old;body mass index(BMI) ranged from 19.87 to 38.54 kg·m^-2 with an average of (28.40±6.18) kg·m^-2;the courses of disease ranged from 5 to 36 months with an average of (18.20±8.98) months; RSNA system was used to assist the positioning of osteotomy. There were 7 males and 23 females in RA group, aged from 55 to 82 years old with an average of (67.83±8.61) years old;BMI ranged from 19.67 to 37.25 kg·m^-2 with an average of (28.01±4.89) kg·m^-2; the courses of disease ranged from 3 to 33 months with an average of (17.93±9.20) months;RA was performed. Operation time, incision length, latent blood loss at 2 weeks after operation and incidence of lower extremity thrombosis were compared between two groups. Hip-knee ankle angle (HKAA), HKAA deviation, lateral distal femoral angle ( LDFA), medial proximal tibial angle (MPTA) and posterior tibial slope (PTS) were compared between two groups;Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and Knee Society score (KSS) were used to evaluate functional recovery before operation, 3 and 6 months after operation.

The operation was performed successfully in both groups, and there were no serious complications such as vascular and nerve injury during operation. The wound healed well at stageⅠafter operation, and the follow-up time was 6 months. The operation time, latent blood loss at 2 weeks after operation and incision length in RSNA group were (94.35±5.75) min, (130.54±17.53) ml and (14.73±2.14) cm, respectively;while (102.57±6.88) min, (146.33±19.47) ml and (16.78±2.32) cm in RA group, respectively. RSNA group was better than RA group (P<0.05). No deep vein thrombosis occurred in both groups at 2 weeks after operation, 5 patients occurred intermuscular vein thrombosisin in RSNA group and 8 patients in RA group, the difference was not statistically significant (P>0.05). In RSNA group, HKAA, LDFA and MPTA were (173.00±5.54) °, (86.96±3.45) °, (82.79±3.35) ° before operation, and (178.34±1.85) °, (89.92±0.42) °, (89.84±0.73) ° at 1 week after operation, respectively. In RA group, HKAA, LDFA and MPTA were (173.31±6.48) °, (87.15±3.40) ° and (82.99±3.05) ° before operation, and (178.52±1.79) °, (90.03±0.39) ° and (90.15±0.47) ° at 1 week after operation, respectively. HKAA, LDFA and MPTA were significantly improved in both groups at 1 week after operation (P<0.05). There were no significant difference in HKAA, LDFA, MPTA and PTS between two groups before operation and 1 week after operation (P>0.05). There was no significant difference in deviation distribution of HKAA at 1 week after operation (χ²=2.611, P=0.456). There were no significant difference in WOMAC and KSS between two groups before operation, 3 and 6 months after operation (P>0.05), and postoperative WOMAC and KSS at 3 and 6 months between two groups were improved compared with those before operation (P<0.05).

Both RA and RSNA system assisted TKA could obtain accurate osteotomy, RA has higher surgical accuracy, RSNA system assisted operation has less trauma, and operation is simpler.