Objective:To investigate the early curative effects of robot-assisted total knee arthroplasty (TKA) in the treatment of valgus knee.Methods:A retrospective study was conducted to analyze the data of 40 patients with valgus knee who had been treated by TKA at Department of Orthopaedics, The 920th Hospital of Joint Logistics Support Force of Chinese People's Liberation Army from January to December 2021. The patients were divided into 2 groups according to whether a robot had been used or not for TKA. In the observation group of 15 cases for which TKA was assisted by a robot, there were 4 males and 11 females with an age of (65.5±6.2) years, and the disease course was 42 (36, 54) months; in the control group of 25 cases for which conventional TKA was performed, there were 8 males and 17 females with an age of (65.8±7.5) years, and the disease course was 42 (36, 60) months. Surgical time, hemoglobin decrease, and knee joint range of motion, American Knee Society Score (KSS), hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA) at 12 months after surgery were compared between the 2 groups.Results:There was no significant difference in the preoperative general data between the 2 groups, indicating comparability ( P>0.05). The surgical time in the observation group was (148.0±21.2) min, significantly longer than that in the control group [(115.2±7.1) min], and the hemoglobin decreased by (11.8±1.1) g/L in the observation group, significantly less than that in the control group [(18.1±1.8) g/L] ( P<0.05). The observation group and the control group were followed up for 13 (13, 14) and 13 (13, 14) months after surgery, respectively, showing no statistically significant difference ( P>0.05). At 12 months after surgery, the KSS knee score, KSS functional score, and knee range of motion in the observation group were (86.1±4.6) points, (86.9±3.1) points, and 115.7°±5.0°, significantly larger than those in the control group [(82.2±3.5) points, (82.8±0.9) points, and 108.2°±5.0°] ( P<0.05). Reexamination of full-length radiographs of both lower limbs in all patients showed good positions of the prostheses and no such adverse events as loosening or sinking at 12 months after surgery. The HKA (178.5°±1.2°) and LDFA (89.1°±0.7°) at 12 months after surgery in the observation group were significantly larger than those in the control group (176.6°±1.5°, 88.2°±8.2°) ( P<0.05); there was no statistically significant difference in MPTA between the 2 groups ( P>0.05). Conclusions:In the treatment of valgus knee, robot-assisted TKA can correct joint deformity, and achieve precise osteotomy and functional alignment of lower limbs, leading to better early curative effects than conventional TKA.

Objective:To investigate the short-term efficacy of rotational femoral neck osteotomy with preservation of the round ligament in the treatment of subchondral insufficiency fracture of the femoral head (SIFFH) in young and middle-aged people.Methods:A retrospective case series study was used to analyze the clinical data of 13 patients with SIFFH, who were admitted to 920th Hospital of Joint Logistics Support Force from January 2017 to January 2022. The patients included 10 males and 3 females, aged 22-49 years [(33.5±8.3)years]. There were 6 patients with fracture on the left hip and 7 on the right hip. All the patients were treated by rotational femoral neck osteotomy with preservation of the round ligament. Postoperatively, standardized joint functional training was given. The operative time and intraoperative bleeding were recorded. The modified Harris hip score and visual analogue score (VAS) were compared preoperatively, at 3, 6 months postoperatively and at the final follow-up. Radiological examinations were used to observe the occurrence of any collapse of the femoral head, non-union at osteotomy site or other complications.Results:The patients were followed up for 13-24 months [(17.9±3.1)months]. The operative time was (127.3±9.8)minutes, with the intraoperative bleeding of (393.9±21.9)ml. The values of modified Harris hip score were (61.6±3.3)points, (80.2±4.4)points, and (91.9±4.1)points at 3, 6 months postoperatively and at the final follow-up, respectively, being significantly higher than the preoperative (51.4±3.5)points (all P<0.05), and there were significant differences between different postoperative timepoints (all P<0.05). The values of VAS were (4.9±1.1)points, (3.0±0.9)points, and (1.4±0.5)points at 3, 6 months postoperatively and at the final follow-up, respectively, being significantly lower than preoperative (6.7±0.9)points (all P<0.05), and there were significant differences between different postoperative timepoints (all P<0.05). Imaging examination showed no femoral head collapse, with all the bones healed at the osteotomy site. There were no serious complications such as bone non-union, incision infection or peripheral nerve injury. Conclusion:Rotational femoral neck osteotomy with preservation of the round ligament in treating SIFFH in the young and middle-aged population has the advantages of shortened operative time, less intraoperative bleeding, promoted hip function recovery, attenuated pain and decreased complications, showing a satisfactory early effect.

Objective:To investigate the safety and effectiveness of robot-assisted total knee arthroplasty (TKA).Methods:From August 2021 to March 2022, the data of 69 patients who received robot-assisted TKA for inflammatory disease of knee in 6 hospitals were collected, including 24 males and 45 females, aged 52±6 years (range, 46-72 years), including 53 cases of knee osteoarthritis,10 cases of rheumatoid arthritis, and 6 cases of traumatic arthritis. Imaging data examination of patients was completed according to the multicenter specification. Preoperatively, the patient's CT data were extracted before surgery and a personalized prosthesis positioning plan was designed by the robotic system to determine the prosthesis size, lower limb force lines, and femoral and tibial osteotomy volumes; intraoperatively, the osteotomy template was robotically controlled to complete the osteotomy according to the prosthesis positioning plan, and the intraoperative osteotomy volumes were measured to verify the accuracy of the robot-assisted TKA osteotomy with the preoperative planning. Postoperatively, the lateral angle of the distal femur, the medial angle of the proximal tibia and the hip-knee-ankle angle were measured in the coronal plane according to radiographs; the postoperative outcome was evaluated 3 months after operation, using the American Knee Society score (KSS), including the KSS knee score and functional score.Results:The operative time was 97.3±2.3 min (range, 80-110 min) and the amount of bleeding was 320.0±6.2 ml (range, 300-350 ml) in 69 patients. Three months after operation, the mean range of motion of knee joint was increased from 82.2°±1.1° before surgery to 119.7°±0.8° after surgery ( t=27.65, P<0.001), and the line of force of lower limb was improved from 160.9°±0.5° before surgery to 178.0°±0.2° after surgery ( t=32.03, P<0.001). KSS-knee score increased from 54.8±0.7 points before operation to 85.0±0.5 points after operation, and KSS-functional score increased from 56.5±0.7 points before operation to 85.9±0.4 points after operation, the difference was statistically significant ( t=35.45, 36.58, P<0.001). The proportion of patients with intraoperative femoral and tibial osteotomies within 2 mm osteotomy error compared with preoperative planning was 97% for the lateral tibial plateau, 100% for the medial tibial plateau, 100% for the lateral distal femur, 99% for the medial distal femur, 93% for the lateral posterior femoral condyle, and 100% for the medial posterior femoral condyle; The proportion of patients with postoperative anteroposterior X-ray measurement angle error within 3° was: 100.0% for the distal lateral femoral angle, 100.0% for the proximal medial tibial angle, and 100% for the hip-knee-ankle angle. No complications occurred in all patients except for one case in which fat liquefaction occurred in the postoperative wound. Conclusion:Robot-assisted TKA is a safe and effective surgical method for the treatment of inflammatory disease of knee with accurate prosthesis installation and good postoperative recovery of lower limb alignment.

Objective:To investigate the mid-and long-term clinical efficacy of modified Colonna arthroplasty in the treatment of unilateral dislocation type developmental dysplasia of hip (DDH) in adolescents.Methods:A total of 28 adolescent DDH patients with unilateral dislocation who underwent modified Colonna capsular arthroplasty from January 2016 to January 2018 in the 920th Hospital of Joint Logistics Support Force of People's Liberation Army were retrospectively analyzed. There were 4 males and 24 females, aged 16.5±5.0 years (range, 10-25 years). The mean body mass index was 21.2±1.1 kg/m 2 (range, 18.7-24.1 kg/m 2). According to DDH classification, 10 cases were Tonnis type III and 18 cases were Tonnis type IV. The postoperative lateral center-edge angle, acetabular coverage, femoral anteversion angle and leg length discrepancy were measured. The operation time, intraoperative blood loss, visual analogue scale (VAS) of hip pain, Harris hip score (HHS) and congenital dislocation of the hip score were recorded. Results:All patients successfully completed the operation and were followed up for 72.1±5.2 months (range, 60-84 months). The operation time was 81.6±4.3 min (range, 70-90 min), the intraoperative blood loss was 177.5±12.6 ml (range, 160-200 ml), and the hospital stay was 6.8±0.7 days (range, 6-9 days). The VAS score of the hip joint was 1.8±0.6 before operation and 2.3±0.6 at the last follow-up, and the difference was not statistically significant ( t=2.845, P=0.224). The preoperative HHS score was 57.1±5.9, and it increased to 87.3±4.0 at the last follow-up, and the difference was statistically significant ( t=-22.141, P=0.001). At the last follow-up, the femoral anteversion angle was 17.0°±1.5°, which was lower than that before operation 41.6°±2.4°, with a statistically significant difference ( t=-44.868, P=0.008). The leg length discrepancy was 10.2±2.3 mm, which was lower than that before operation (26.4±6.1 mm), with a statistically significant difference ( t=-12.892, P<0.001). The lateral center-edge angle was 28° (26°, 30°), and the acetabular coverage rate was 78% (76%, 79%). The curative effect evaluation standard score of congenital dislocation of the hip was 24 (16.7, 25.7) points, including 7 excellent cases, 14 good cases, 4 fair cases, and 3 poor cases. The excellent and good rate was 75% (21/28). Conclusion:The modified Colonna arthroplasty for the treatment of unilateral dislocation DDH in adolescents has good mid-and long-term hip function recovery and radiographic improvement.