Abstract:[Objective] To compare the short-term outcomes of cruciate retaining (CR) versus posterior stabilized (PS) total knee arthro- plasty (TKA) for moderate and severe knee osteoarthritis (KOA) . [Methods] A retrospective study was done on 142 patients (142 knees) who underwent TKA for moderate and severe unilateral KOA from January 2015 to December 2017. According to preoperative doctor-pa- tient communication, 85 patients (85 knees) received CR-TKA, while the remaining 57 patients (57 knees) received PS -TKA. The periop- erative, follow-up and imaging documents were compared between the two groups. [Results] All the patients in both groups had operation completed successfully without neurovascular injuries and other serious complications. The CR group proved significantly superior to the PS group in terms of intraoperative blood loss, displacement measured in intraoperative anterior drawer test, postoperative drainage and walking time postoperatively (P＜0.05) . The patients in both groups were followed up for more than 36 months, and the CR group resumed full weight-bearing activity significantly earlier than the PS group (P＜0.05) . The VAS scores decreased significantly (P＜0.05) , while flex- ion- extension ROM, AKSS clinical and functional scores, as well as HSS scores significantly increased over time in both groups (P＜0.05) , which in the CR group were significantly superior to those in the PS group at 1 month after surgery (P＜0.05) , whereas become not statisti- cally significant between them at 6 and 36 months postoperatively (P＞0.05) . With respect to radiographs, the femorotibial angle (FTA) de- creased significantly (P＜0.05) , while the medial proximal tibial angle (MPTA) increased significantly postoperatively in both groups com- pared with those preoperatively (P＜0.05) , with no significant differences between the two group at any matching time points (P＞0.05) . How- ever, the CR group had significantly less posterior tibial slope (PTS) than the PS group at 6 and 36 months after operation (P＜0.05) . [Conclusion] Both CR and PS prostheses for TKA do effectively treat KOA. By contrast, the CR prosthesis takes benefits of less surgical trauma and faster functional recovery, however, long-term follow-up is still needed to compare the efficacy of the two prostheses.

Abstract:[Objective] To investigate the clinical outcomes of tibia transverse transport (TTT) for diabetic foot ulcer (DFU) complicat- ed with chronic kidney disease (CKD) . [Methods] A retrospective study was conducted on the patients who underwent TTT for DFU in our department from February 2015 to August 2019. Among them, 67 patients with chronic kidney disease were fall into the CKD group, while the other 53 patients without kidney disease were termed as the non-CKD group. The clinical and auxiliary examination results were com- pared between the two groups. [Results] The CKD group consumed significantly longer operation time, hospital stay and external fixator wearing time than non-CKD group (P＜0.05) . All the patients were followed up for 4~24 months, with an average of (14.38±4.38) months. During the follow-up period, 7 patients in CKD group died of cardiovascular and cerebrovascular diseases, while no patients in the nonCKD group died (P＜0.05) . Although there was no significant difference in the healing rate of foot ulcers between the two groups at the last follow-up (P＞0.05) , the CKD group got ulcer healing significantly later than the non-CKD group (P＜0.05) . At the last follow-up, the CKD group had higher recurrence rate of foot ulcers and amputation than the non-CKD group, despite of the fact that no significant differences were noted between the two groups (P＞0.05) . Angiographically, the findings significantly improved in both groups after surgery(P＜0.05) , which in the non-CKD group proved significantly superior to the CKD group at 1 month postoperatively, and bacame not statistically signifi- cant between the two groups at 3 months after surgery(P＞0.05) . In terms of lab tests, CRP, Cr and HbA1c significantly decreased in both groups 1 month after operation compared with that before operation (P＜0.05) , whereas the Hb, Alb and Urea remained unchanged in both groups (P＞0.05) . At the corresponding time point, the CKD group had significantly lower Hb and Alb (P＜0.05) , while significantly higher Urea, Cr and CRP than the non-CKD group (P＜0.05) . [Conclusion] TTT for treatment of diabetic foot ulcer complicated with chronic kid- ney disease does achieve a higher chance of ulcer healing, with low amputation and recurrence rates.

Abstract:[Objective] To evaluate the clinical results of 3D printed guider assisted epiphyseal block plate placement in correction of lower limb deformities in children. [Methods] From January 2016 to December 2018, a total of 37 children with bilateral genu varus or genu varus were enrolled in this study, and randomly divided into two groups. Among them, 20 children had the plate inserted with assistance of the 3D printed guider, while the remaining 17 patients had the plate implanted with traditional free-hand technique. Perioperative, followup and imaging data of the two groups were compared. [Results] All the children were operated on successfully without serious complica- tions. The guider group proved significantly superior to the free-hand group in terms of operation time, plate placement time and fluoroscopy times (P＜0.05) . All patients were followed up for more than 12 months. The length of lower limbs significantly increased (P＜0.05) , whereas the knee range of motion (ROM) remained unchanged at the latest follow up compared with those preoperatively (P＜0.05) . At any corre- sponding time points, there were no significant differences in the length of lower limbs and the ROM between the two groups (P＞0.05) . In terms of imaging evaluation, the femorotibial angle (FTA) , mechanical medial proximal tibial angle (mMPTA) and mechanical lateral distal femoral angle (mLDFA) significantly improved in both groups at the latest follow-up compared with those preoperatively (P＜0.05) , while the discrepancy in bilateral lower limb length was slightly decreased without statistically significant differences (P＞0.05) . However, there were no significant differences in abovementioned radiographic items between the two groups at any corresponding time points (P＞0.05) . [Conclusion] The personalized 3D printed guider designed in this study does reduce the operation time and the number of intraoperative X-ray expo- sure during 8 shaped plate placement in epiphysiodesis for correction of lower limb deformities in children.

Abstract:[Objective] To investigate the management and factors related to closed reduction failure of humeral supracondylar fracture in children. [Methods] From June 2019 to December 2020, a total of 375 children with supracondylar fracture of humerus were treated in our hospital. All patients underwent closed reduction (CR) firstly. If the CR proved successful, the patients had percutaneous cross Kirsch- ner wire for internal fixation conducted (the CR group) , while the unsuccessful patients underwent open reduction (OR) and cross Kirsch- ner wire fixation (the OR group) . The clinical and imaging data were compared between the two groups. In addition, univariate comparison and binary logistic regression analysis of preoperative data based whether CR successful were performed to search the factors related to CR failure. [Results] Among 375 patients, 348 patients had CR performed successfully, accounting for 92.80%, whereas 27 patients got CR failed to change OR, accounting for 7.20%. Finally, all patients got fracture reduction and cross Kirschner wire fixation successfully in both groups. The CR group proved significantly superior to the OR group in terms of operation time, intraoperative fluoroscopy times, hospital stay, incidence of early complications and VAS score 1 day postoperatively (P＜0.05) . All the patients were followed up for 14~46 months, with an average of (23.40±4.59) months. There were no statistically significant differences between the two groups in the time to remove the plaster splint, the time to resume full weight-bearing activities, elbow flexion-extension ROM and Flynn's scales at the latest follow-up (P＞ 0.05) . Radiographically, satisfactory fracture reduction achieved in all children of both groups, with sound fracture healing, whereas no sig- nificant differences in carrying angle and Baumann angle between the two groups at the last follow-up (P＜0.05) . Regarding to univariate comparison, the CR group had significantly less BMI, fracture complexity, time elapsed between injury and surgery, as well as damage ener- gy extent than the OR group (P＜0.05) . As results of logistic regression, fracture complexity type (OR=8.251, P=0.037) , damage energy (OR=1.593, P=0.035) , and duration from injury to operation (OR=1.400, P=0.026) were independent risk factors for CR failure of supracon-dylar humeral fractures in children. [Conclusion] The children who fail to initial closed reduction of humeral supracondylar fracture should be changed to open reduction in time, and still archive satisfactory results eventually. The fracture complexity, high energy injury and long duration from injury to operation are the main risk factors for the failure of initial closed reduction.

Abstract:[Objective] To compare the clinical efficacy of two incisions for open reduction and internal fixation (ORIF) in the treat- ment of intraarticular calcaneus fractures. [Methods] From March 2016 to January 2020, a total of 35 patients received surgical treatment for calcaneal fractures in our department. The patients were divided into two groups by random number table method, and received ORIF. Of them, 16 patients in the minimally invasive group had ORIF performed through tarsal sinus incision, while the other 19 patients in the conventional group were through the conventional lateral L-shaped incision. The perioperative, follow-up and imaging data were compared between the two groups. [Results] The minimally invasive group proved significantly superior to the conventional group in terms of opera- tion time, blood loss, incision length, incision healing and hospital stay (P<0.05) , but the former had significantly greater number of intraop- erative fluoroscopy than the latter (P<0.05) . All the 35 patients were followed up for more than 12 months. There was no statistically signifi- cant difference in the time to return to full weight-bearing activity between the two groups (P>0.05) . The VAS scores decreased significant- ly (P<0.05) , whereas the AOFAS and Maryland scores increased significantly over time in both groups (P<0.05) . At any corresponding time points, there was no significant difference in the above scores between the two groups (P>0.05) . Radiographically, all patients in both groups got fracture healing well, with significant improvements of calcaneal width, height, and length as well as Gissane angle and Bohler angle at the latest follow-up compared with those preoperatively (P<0.05) . However, there was no significant difference in aforesaid imag- ing measures between the two groups at any matching time points (P>0.05) . [Conclusion] Both tarsal sinus incision and the conventional lateral L-shaped incision for ORIF of intra-articular calcaneal fractures achieve satisfactory clinical outcomes, by comparison, the tarsal si- nus incision has a benefit of minimizing iatrogenic trauma.

Abstract:[Objective] To compare the clinical efficacy of hip arthroscopy versus open surgery in the treatment of femoroacetabular im- pingement (FAI) . [Methods] The literatures of CNKI, Chinese Biomedical literature, Wanfang, VIP, PubMed, Embase, Web of Science and the Cochrane Library database were searched until April 30, 2021. The clinical study on comparison between hip arthroscopy and open sur- gery for FAI was collected. The quality assessment and then data extraction were conducted by two independent reviewers using Cochrane 5.1 risk bias software for the literatures searched, and an meta-analysis was conducted with RevMan 5.3 software by integrating the observa- tional items of each study. [Results] A total of 8 articles were included, involving 862 patients, including 427 patients in the arthroscopy group and 435 patients in the open group. As results of meta-analysis, the arthroscopy group proved significantly superior to the open group in terms of Non- arthritic Hip Score (NAHS) , Hip Outcome Score-Activities of Daily Living (HOS-ADL) , and complication rate at 3 months postoperatively (P＜0.05) . However, there were no significant differences in NAHS score, HOS-ADL score, Modified Harris Hip Score (mHHS) , Hip Outcome Score-Sport Specific Subscale (HOS-SSS) , femoral head-neck offset (HNO) and α angle between the two groups at 12 months postoperatively (P＞0.05) . [Conclusion] Both hip arthroscopy and open surgery do achieve satisfactory clinical out- comes for FAI, by comparison, hip arthroscopy takes obvious advantages over open surgery in the incidence of complications and initial treatment efficacy in term of NAHS and HOS-ADL scores.

Abstract:The chronic lateral ankle instability is a common kind of sports injuries. Using the term of internal brace (IB) AND ligament OR ankle, the literatures on IB applicated in surgical management of chronic lateral ankle instability were searched in PubMed, Embase and CNKI, involving biomechanical features, suitable indications, surgical methods and clinical performance. The biomechanical tests showed that enhancement of ankle lateral ligaments with IB has good performance to resume the immediate stability. Compared with modi- fied Brostr?m procedure, the IB only or combined application of IB provided excellent clinical and radiological outcomes, especially for pa- tients with general joint laxity, revision surgery and patients who need quick return to exercise or sports. The IB should be applied in actual- ly necessary patients, whereas should not overuse it in other patients without high risk of failure.

Abstract:Low back pain (LBP) is one of the most common disorders met in orthopaedic practice worldwide, resulting in severe soci- etal burden. It is believed highly associated with progression of intervertebral disc degeneration (IDD) , whereas its mechanism still needs to be further studied. In recent years, it has been shown that hypoxia inducible factor 1α (HIF1α) , one of the important genes leading to the occurrence and development of IDD, is widely involved in regulating the pathological process. In this paper, we review the progress of HIF1α role in IDD in previous studies, and summarize the potential mechanisms and research trends in focus.

Abstract:[Objective] To explore the effect of different postoperative activities on tendon-bone healing of anterior cruciate ligament (ACL) reconstruction in rabbits. [Methods] Sixty-four 6-month-old New Zealand white rabbits were randomly divided into 4 groups with 16 rabbits in each group, including the immobilized (IM) , free motion (FM) , low-intensity motion (LIM) , and high-intensity motion (HIM) groups. All the animals underwent right knee ACL resection followed by ACL reconstruction with autogenous semitendinosus tendon. The rabbits in the IM group had the knee fixed with plaster cast at 120° flexion after 2 weeks, those in the FM group were placed in free motion without restriction in the cage, whereas those in the LIM group and HIM group ran at 0.2 m/s and 0.5 m/s respectively on the running plat- form, once every 3 days for 0.5 hour each time. At 8 weeks after operation the animals were sacrificed for gross observation, histological ex- amination and biomechanical tests. [Results] Only 3 animals in HIM group showed mild claudication, with positive drawer test, which proved internal fixation failure that the tendon was partially pulled out, but certain length of tendon remained in the tunnel. In term of histo- logical observation, the tendon-bone interface in IM group still had more obvious boundaries and fissures, with more inflammatory cells and vascular tissues, while scanty chondrocytes compared with the FM group. Histological score was ranked from high to low as the LIM group ＞ the HIM group ＞ FM group ＞ IM group with statistically significant differences among them (P＜0.05) . In terms of biomechanical tests, the maximum strength to failure was ordered from high to low as LIM group ＞ the HIM group ＞ FM group ＞ IM group with statistically signifi- cant differences among them (P＜0.05) , whereas the maximum displacement was arranged from low to high as LIM group ＜ the HIM group ＜ FM group ＜ IM group with statistically significant differences among them (P＜0.05) . [Conclusion] In this study, appropriate activities after ACL reconstruction are conducive to tendon-bone healing, whereas complete immobilization or high intensity activities are harmful to ten- don-bone healing.

Abstract:[Objective] To introduce the surgical technique and preliminary clinical results of closed osteotomy by fracture line through posterior approach for ankylosing spondylitis stress fracture. [Methods] From January 2010 to June 2016, 16 patients with ankylosing spon- dylitis complicated with thoracolumbar stress fracture were treated by the above surgical procedures. A posterior midline incision was made to expose the fractured vertebra bilaterally to the anterior part, and then 2~3 pairs of pedicle screws were placed respectively on the seg- ments superior and inferior to the affected vertebra. After the corresponding lamina and facet process were removed, the fracture space on the vertebral body was identified and debrided, then a V-shaped osteotomy was performed beside the fracture line, followed by bone auto- graft or allograft implanted into the osteotomy space. Placing bilateral rods, the screw-rod systems were adjusted to close the osteotomy gap, eventually were fastened definitively. [Results] All the 16 patients had the operations performed successfully. Except one patient who was suffered from significant muscle weakness postoperatively, which well recovered 4 months later by rehabilitation, all the patients had no se- rious complications. The VAS and ODI scores significantly decreased at the latest follow-up compared with those before surgery (P＜0.05) . Radiographically, the thoracic kyphosis, global kyphosis, angle of the fusion levels, local kyphosis and sagittal vertical axis significantly im- proved at the latest follow-up compared with those preoperatively (P＜0.05) . Bony fusion achieved at all osteotomy sites without loosening of internal fixators. [Conclusion] This closed osteotomy by fracture line through posterior approach has benefits of complete debridement of the lesion between the fracture ends, obvious pain relief and effective correction of the deformity, is facilitated to fracture healing with high safety.

Abstract:[Objective] To introduce the surgical technique and preliminary clinical results of percutaneous retrograde cannulated screw for superior pubic ramus fractures by a curved guide wire. [Methods] From January 2019 to March 2020, 11 patients underwent abovesaid procedure for superior pubic ramus fractures of pelvic fractures. If the guide wire cannot pass through the fracture or impact the bone around the acetabulum, a cannulated screw 7.3 mm in diameter and length premeasured preoperatively was driven along the 2.5 mm guide wire to the inner side of the fracture, then a 2.0mm guide wire bended 5°~10° at 1cm away from the tip was used to replace the previ- ous wire through the cannulated screw. Handling the cannulated screw with a screwdriver to assist the reduction of the fracture site, and ad- just the tip of the guide needle to pass through the fracture aiming to the anterosuperior part of acetabulum, then the 7.3 mm cannulated screw was driven further along the 2.0 mm guide wire, and take out the guide wire before the tip of the cannulated screw reached the bend- ing point of the wire to prevent the screw from cutting the tip of the wire. [Results] A total of 13 patients had the retrograde superior pubic ramus screws placed smoothly with screw placement time of (23.77±4.79) minutes and number of fluoroscopies of (28.15±5.68) times. No complications, such as infection, nerve injury and lower extremity deep venous thrombosis, happened in anyone of them. All patients got fractures healing with the excellent and good rate of 100% in Majeed criteria at the latest follow-up. [Conclusion] This curved guide wire technique used in retrograde cannulated screw placement does reduce the risk of screw entering acetabulum, improve the quality of fracture reduction and shorten the operation time for superior pubic ramus fracture.

Abstract:[Objective] To introduce the surgical technique and primary clinical outcomes of navigation assisted lateral lumbar inter- body fusion in the unchanged lateral position. [Methods] From October 2017 to May 2019, 27 patients underwent abovementioned surgical procedures for degenerative lumbar spondylolisthesis. As the patients were placed in right lateral position, discectomy and cage implanta- tion of the involved disc were firstly conducted though a small incision on the left side. Subsequently, maintaining the position unchanged, the navigation reference fixed on the left iliac crest and the segmental three-dimensions images were obtained by O-arm fluoroscopy and transferred to navigator. Finally, percutaneous pedicle screw-rod placement was performed under real-time navigation guidance. [Results] All the 27 patients had operation performed smoothly without serious complications. A total 122 pedicle screws were placed in the 27 pa- tients with an average screw placement time of (9.22±3.84) min/screw and accuracy of pedicle screw placement of 93.4% based on Gertz- bein-Robbins criteria. At the latest follow-up ranged from 3 to 24 months, the ODI and VAS scores for low back pain and leg pain, as well as the slippage rate, intervertebral space height and cross-sectional of the dural sac measured on radiographs significantly improved com- pared with those preoperatively (P<0.05) . According to MacNab's criteria, the excellent and good rate of clinical outcome was 100%. [Conclusion] This navigation assisted lateral lumbar interbody fusion in the unchanged lateral position is a safe and high-efficient surgical tech- nique.

Abstract:[Objective] To evaluate the clinical outcomes of rod-screw fixation of the affected vertebra combined with bone autograft- ing of the pars defect for lumbar isthmic spondylolysis in adolescents. [Methods] From May 2013 to July 2016, a total of 31 patient who all were male and aged from 17 to 29 years with the main symptom of lumbago, underwent abovementioned surgical procedures for lumbar isth- mic spondylolysis in our department. The clinical and imaging consequences were evaluated. [Results] All patients were successfully oper- ated on without serious complications such as nerve and vascular injuries, whereas with operative time of (109.10±15.12) min, and the intra- operative blood loss of (133.55±58.12) ml. As time went during the follow-up lasted for 13~35 months, with an average of (17.65±4.22) months, the ODI and VAS scores decreased significantly (P＜0.05) . In terms of imaging evaluation, the lumbar lordosis (LL) decreased sig- nificantly (P＜0.05) , whereas the isthmic union ratio increased significantly over time (P＜0.05) . No loosening or breaking of the rod-screw system was noticed during follow-up in anyone of them, whereas bony union of the isthmus was achieved in all patients at the last followup. [Conclusion] This rod-screw fixation of the affected vertebra combined with bone autografting of the pars defect is a simple and effec- tive surgical method for lumbar isthmic spondylolysis in adolescents.

Abstract:[Objective] To investigate the clinical efficacy of debridement combined with antibiotic-loaded calcium sulfate implanta- tion in the treatment of sclerosing osteomyelitis. [Methods] A retrospective study was conducted on 28 patients who received surgical de- bridement combined with antibiotic-loaded calcium sulfate implantation for sclerosing osteomyelitis in our department from February 2016 to November 2020. The clinical and laboratory results were observed. [Results] All 28 patients were successfully operated on without seri- ous complications. One week after surgery, the swelling and pain disappeared gradually with well incision healing in all the patients. The VAS score significantly decreased at the latest follow-up lasted for (30.18±18.43) months on an average compared with that preoperatively (P＜0.05) . None of the patients had pathological fracture, whereas 2 patients had local recurrence after surgery, which were cured after re- vised debridement and antibiotic-loaded calcium sulfate implantation. Radiographically, the lesion healed with bone remodeling and com- plete absorption of the implant at the last follow-up. The CRP, ESR and WBC significantly declined at the latest follow-up compared with those preoperatively (P＜0.05) . [Conclusion] Debridement combined with antibiotic-loaded calcium sulfate implantation does effectively control infection and relieve pain for sclerosing osteomyelitis.

Abstract:[Objective] To evaluate the clinical outcomes of 3D printing-assisted percutaneous cannulated screw fixation of acute car- pal scaphoid fracture. [Methods] From January 2019 to December 2020, a total of 60 patients with carpal scaphoid fracture were enrolled in this study, and were divided into two groups by random number table method, with 30 patients in each group. Before surgery, mimics soft- ware and 3D printer were used to make 1:1 real fracture model and percutaneous guider, and then palmar percutaneous screw placement was conducted under the guider in the 3D group. By comparison, conventional percutaneous screw placement was performed in the free- hand group. The clinical and imaging data of the two groups were compared. [Results] Surgical procedures were successfully completed in both groups. The 3D group proved significantly superior to the freehand group in terms of operation time, fluoroscopic frequency and VAS score one day after surgery (P＜0.05) . The patients in both groups were followed up for 8~15 months, with an average of (10.14±2.35) months. The 3D group had significantly lower incidence of postoperative complications than the freehand group (P＜0.05) , despite no signifi- cant difference in VAS score and clinical outcome grades between the two groups at the latest follow-up (P＞0.05) . In terms of imaging, the 3D group proved significantly superior to the freehand group in accuracy of screw insertion point and screw length (P＜0.05) . [Conclusion] This 3D printing- assisted percutaneous cannulated screw internal fixation for acute carpal scaphoid fracture does shorten the operation time and reduce intraoperative fluoroscopic frequency.

Abstract:[Objective] To compare the healing of L-shaped lateral incision by figure-of-eight vertical tight suture versus Allg?werDonati vertical mattress suture for open reduction internal fixation (ORIF) of calcaneal fractures. [Methods] From January 2018 to Febru- ary 2021, 60 patients received ORIF for Sanders type III calcaneal fractures through L-shaped lateral incision. Of them, 31 patients had the incision closed by figure- of- eight vertical tight suture (the figure- 8 group) , while the remaining 29 patients were with traditional Allg?wer-Donati vertical mattress suture (the AD group) . The early local skin reaction and incision healing were compared between the two groups. [Results] The figure-8 group proved significantly superior to the AD group in terms of the incision closure time, the severity of ear- ly skin reaction and the area of early severe skin reaction (P＜0.05) . The incision skin temperature remained unchanged significantly over time in both groups (P＞0.05) , which were not statistically significantly different between the two groups at any matching time points (P＞ 0.05) . In the figure-8 group, 3 cases had partial necrosis of the epidermis at the arc site of the incision without infection and dehiscing, which healed delayed by dressing change. In contrast, in AD group, 6 cases had incision dehiscing at the "L" shaped corner, which healed after 4 weeks of dressing change, additionally other 3 cases had wound infection with internal fixation exposed, which healed by removal of internal fixation, wound dressing change for 8 weeks. The figure-8 group was significantly superior to the AD group in term of incision heal- ing (P＜0.05) . [Conclusion] This figure-of-eight vertical tight suture does reduce local adverse reactions and improve incision healing.

Abstract:[Objective] To investigate the influence of medial unicompartmental knee arthroplasty (UKA) on knee kinematics. [Methods] A total of 9 patients who were undergoing UKA for medial knee osteoarthritis were included into this study. A biplane X-ray device was used to collect the imaging data during walking before and after the operation, in addition, the three-dimensional model of the bone was established by CT scanning, and the 3D model of the bone was compared with the X-ray. The six-freedom movements between the femur and tibia and the position of the contact center point of the medial and lateral tibial plateau were measured. [Results] Before operation, there was no significant difference in flexion and extension angle between the involved and uninvolved knees (P＞0.05) , but significant dif- ference was found in internal and external varus and rotation and medial compartment contact center (P＜0.05) . After operation, the flexion and extension angle between the involved and uninvolved knees showed no significant difference as well (P＞0.05) , the internal and exter- nal varus and rotation and medial compartment contact center improved significantly (P＜0.05) , and no significant diffeence was found be- tween involved and uninvolved knees (P＞0.05) . The anterior displacement deformity of tibial medial compartment contact center improved significantly in the involved knee, however, significant difference was still noted compared to the uninvolved side (P＜0.05) . [Conclusion] UKA can effectively improve the inherent biomechanical indexes of knee gait cycle, especially in force line and rotation, but there is still a certain forward movement in the contact center of medial compartment.

Abstract:[Objective] To evaluate the clinical outcomes of femoral neck system (FNS) in the fixation of Pauwels type III femoral neck fractures. [Methods] From March 2020 to August 2020, 23 patients underwent reduction and internal fixation with FNS for Pauwels type III femoral neck fracture. The clinical and imaging consequences were evaluated. [Results] All patients were successfully operated on without neurovascular injury and other complications. During follow-up period lasted for (17.22±1.55) months, the Harris score, extension-flexion range of motion (ROM) and internal-external rotation ROM increased significantly over time (P＜0.05) . Among them, 22 patients resumed- full weight-bearing activity in 3~6 months, with an average of (4.42±0.95) months, while another patient who remained unable to walk with full weight-bearing until the last follow-up. Radiographically, all patients achieved satisfactory fracture reduction according to Garden in- dex on the anteroposterior and lateral radiographs. Femoral neck shortening increased significantly over time (P＜0.05) , with shortening oc- currence of 5/23 (21.74%) . By the latest follow-up, all patients got fracture healing except 1 case. [Conclusion] This FNS used for fixation of Pauwelstype III femoral neck fracture does significantly reduce postoperative complications and achieve satisfactory clinical results.

Abstract:[Objective] To compare the clinical outcomes of suture anchor versus loop plate used in coracoclavicular reconstruction for acromioclavicular dislocation. [Methods] A retrospective study was conducted on 65 patients who underwent coracoclavicular reconstruc- tion for Tossy type Ⅲ acromioclavicular dislocation. Of them, 32 patients had suture anchor used, while the remaining 33 patients had loop plate used for the reconstruction. The clinical and imaging results were compared between two groups. [Results] The anchor group proved significantly superior to the plate group in terms of operation time, blood loss and incision length (P＜0.05) . The VAS score significantly de- creased, whereas the Constant-Murley score significantly increased in both groups at 2 years postoperatively compared with those before op- eration (P＜0.05) , however there was no significant difference in abovesaid scores between two groups at any matching time points (P＞ 0.05) . Radiographically, the acromioclavicular distance and coracoclavicular distance significantly decreased in both groups postoperative- ly compared with those preoperatively (P＜0.05) . The anchor group had significantly greater coracoclavicular distance than the plate group at 2 years postoperatively (P＜0.05) . [Conclusions] Both suture anchor and loop plate used for coracoclavicaular reconstruction do alleviate shoulder pain and restore shoulder joint function. The suture anchor reconstruction is inferior to the loop plate in maintaining the coracocla- vicular distance, despite of advantages of less trauma and less operation time consumed.

Abstract:[Objective] To evaluate the outcomes during hospitalization of team resource management (TRM) used in total hip arthro- plasty (THA) for ankylosed hip secondary to ankylosing spondylitis (AS) . [Methods] A retrospective study was done on 37 patients (45 hips) who underwent THA for ankylosed hip after AS in our hospital from August 2018 to September 2021. According to doctor- patient communication, 20 patients (25 hips) received TRM intervention during hospitalization (TRM group) , while the remaining 17 patients (22 hips) received routine medical care intervention (routine group) . The clinical and blood test data during hospitalization were compared be- tween the two groups. [Results] All patients in both groups were successfully operated on without serious complications. The TRM group proved significantly superior to the routine group in terms of intra-operative anesthesia time and VAS score at 7 days postoperatively (P＜ 0.05) . Regarding to blood test, the TRM group was better than the routine group in Hb and Hct (P＜0.05) . [Conclusion] The TRM does im- prove preoperative preparation efficiency with considerably improved satisfaction of patient with ankylosed hip after AS.