[Clinical study of the lower limb constitutional alignment restoration in patients undergoing robotic-assisted functionally aligned total knee arthroplasty].

OBJECTIVE: To compare and analyze the early clinical efficacy of robotic-assisted functionally aligned total knee arthroplasty (RFA-TKA) and manual mechanically aligned total knee arthroplasty (MMA-TKA).

METHODS: A retrospective analysis was conducted on 58 patients with end-stage knee osteoarthritis who underwent total knee arthroplasty (TKA) between February 2024 and January 2025. According to the different surgical methods, the patients were divided into the RFA-TKA group and the MMA-TKA group.There were 26 patients in the RFA-TKA group, including 7 males and 19 females, aged from 58 to 80 years old with an average of (69.08±5.93) years old;robotic-assisted functional alignment was adopted in this group. The MMA-TKA group consisted of 32 patients, including 9 males and 23 females, aged from 53 to 78 years old with an average of (66.59±7.76) years old;manual mechanical alignment was used in this group. Surgical indicators of the two groups were compared, including operation time, hemoglobin loss, and soft tissue release. Postoperative clinical outcomes were evaluated using Knee Society score-the knee dcore (KSS-K) and the visual analogue scale (VAS) for knee pain. Postoperative radiological measurements micluded, the hip-knee-ankle (HKA) angle, mechanical lateral distal femoral angle (mLDFA), and medial proximal tibial angle (MPTA) were measured.

RESULTS: All patients were followed up for more than 3 months. There was no statistically significant difference in the operation time between two groups (P>0.05). The hemoglobin loss in the RFA-TKA group on the first day after surgery was (5.08±4.07) g·L-1, which was less than that of the MMA-TKA group (14.03±12.49) g·L-1, and the difference was statistically significant (P<0.05). The number of patients who underwent soft tissue release in the RFA-TKA group was 5 cases, which was less than 32 cases in the MMA-TKA group, and the difference was statistically significant (P<0.05). At 3 months after surgery, the HKA angle (177.71±1.05)°, mLDFA (88.30±0.64)° and MPTA (87.53±1.47)° of the RFA-TKA group were all smaller than those of the MMA-TKA group (179.19±0.57)°, (89.14±0.59)° and(89.27±0.62)° respectively, with statistically significant differences (all P<0.05). The KSS-K of the RFA-TKA group was (92.50±3.64) points, which was higher than that of the MMA-TKA group(86.22±3.38) points, and the difference was statistically significant(P<0.05). For the VAS score of knee pain during walking, the RFA-TKA group (0.31±0.62) points was lower than the MMA-TKA group (1.03±1.12) points, and the difference was statistically significant (P<0.05).

CONCLUSION: Domestic robot-assisted functionally aligned TKA effectively restores the constitutional alignment of the lower limb, reduces the need for soft tissue release, minimizes intraoperative blood loss, alleviates postoperative pain, and achieve superior early clinical outcomes.