Objective To evaluate the results of NiTi shape memory alloy four-corner arthrodesis concentrator (NTMA-FCAC) for carpal collapse. Methods We reviewed retrospectively 13 patients who underwent scaphoid excision with four-corner arthrodesis using NTMA-FCAC for carpal collapse from August 2006 to June 2009. There were eight males and five females, with an average age of 38 years (range, 23-61years). The cause of carpal collapse was SNAC in 7 cases, perilunate dislocations in five and SLAC in one.The injury mechanisms included traffic accidents (5 cases), falling from a height (4 cases), crashes (3 cases)and sprain (1 case). Objective measurements included grip strength and range of the wrist. Radiographs were performed in all patients. A visual analogue scale (VAS) was used to assess wrist pain. The results were evaluated according to the Krimmer wrist scores. Results The mean follow-up time was 26.5 months (range,6-36 months). Clinical evaluation yielded the mean grip strength of (32.49±6.21) kg (80.8% of opposite side).The mean range of the wrist reached over 53% of the healthy side. Non-union and wound infection were not seen. The mean VAS scores had improved from 4.46±1.27 preoperatively to 1.31 ±0.95 postoperatively. The mean pain scores under stress had improved from 7.00±1.41 preoperatively to 2.62±1.26 postoperatively.There were remarkable differences between them. The mean Krimmer wrist score was 79. Conclusion Four-corner arthrodesis using NTMA-FCAC is an effective method for carpal collapse, preserving a majority of wrist function.

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 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 explore the clinical efficacy of the San Diego osteotomy in treating developmental dysplasia of the hip (DDH) in children.Methods:A retrospective analysis was conducted on 33 pediatric cases of posterolateral acetabular dysplasia treated with the San Diego osteotomy at the 920th Hospital of the People's Liberation Army Joint Logistics Support Force in China from August 2018 to August 2022. The cohort included 3 males (4 hips) and 30 females (36 hips), with an average age of 4.9±1.4 years (range, 2-8 years). Among these, 32 cases (38 hips) were diagnosed with DDH, and 1 case (2 hips) with paralytic dislocation of the hip. According to the T?nnis classification, 3 hips were classified as type II, 25 hips as type III, and 12 hips as type IV. The San Diego osteotomy technique was utilized to enhance the posterior lateral acetabular coverage, combined with femoral osteotomy to adjust the hip abduction, flexion, and adduction angles. Postoperative outcomes were assessed using the modified Severin radiographic classification and the McKay grading system.Results:All 33 patients were followed up for an average of 37.70±18.44 months (range, 12-74 months). No cases of postoperative hip redislocation or residual acetabular underdevelopment were observed. The hip abduction angle improved from 24.98°±3.48° at 6 weeks postoperatively to 37.28°±4.63° at the 3-month follow-up, and 64.05°±3.82° at the 6-month follow-up, with a statistically significant difference ( F=77.327, P<0.001). The hip flexion angle increased from 26.34°±5.05° at 6 weeks postoperatively to 76.53°±4.38° at 3 months, and 106.47°±2.29° at 6 months, also showing a statistically significant difference ( F=54.377, P<0.001). The hip adduction angle progressed from 1.73°±1.18° at 6 weeks postoperatively to 12.33°±1.97° at 3 months, and 29.03°±4.17° at 6 months, with a significant difference ( F=45.162, P<0.001). The McKay hip joint grading system indicated 11 excellent, 20 good, and 9 acceptable outcomes, yielding an overall excellent and good rate of 78%. The Severin radiographic grading revealed 16 hips at grade I and 24 hips at grade II. Five patients (5 hips) experienced transient vascular compromise of the femoral head at 3 months postoperatively, which resolved after a 1-month non-weight-bearing period. At the final follow-up, one patient had residual femoral head enlargement in the right hip, while the remaining 32 cases showed satisfactory ossification and remodeling of the femoral head. Conclusion:The San Diego osteotomy significantly enhances hip joint range of motion and results in satisfactory hip joint function in children with developmental dysplasia of the hip

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.