Abstract:[Objective] To compare the clinical efficacy of 3-pair pedicle screws with or without placement in the injured vertebrae for flexion-distraction thoracolumbar fractures. [Methods] A retrospective study was performed on 43 patients who received pedicle screw fixa- tion of flexion-distraction thoracolumbar fractures in our department from January 2017 to December 2020. According to the preoperative doctor-patient communication, 20 cases underwent 3-pair pedicle screws with non-placement in the injured vertebrae (PSNIV) , while the remaining 23 cases received 3-pair pedicle screws with placement in the injured vertebrae (PSIV) . The two groups were compared regard- ing perioperative, follow-up and radiographic documents. [Results] All patients in both groups received successful surgery with no injury to nerves. The PSNIV group had significantly longer incision than the PSIV (P＜0.05) , despite no significant difference in terms of operative time, intraoperative blood loss, intraoperative fluoroscopy and hospital stay between the two groups (P＞0.05) . Patients in both groups were followed up for 16~23 months, with an average of (19.6±5.2) months. There was no significant difference in the time to return walking and the time to resume full-weight bearing activity between the two groups (P＞0.05) . The ASIA grade for neurological function, as well as VAS, ODI and JOA scores improved significantly in both groups over time (P＜0.05) , whereas which proved not significantly different between the two groups at any matching time points (P＞0.05) . Regarding to radiographic assessment, the anterior vertebral height and lumbar lordosis of the two groups was significantly increased (P＜0.05) , while the local kyphotic Cobb Angle decreased significantly immediately postopera- tively and at the latest follow-up compared with those preoperatively (P＜0.05) . There was no significant difference in the above imaging pa- rameters between the two groups before operation (P＞0.05) . The PSNIV proved significantly superior to the PSIV in term of correction of the anterior vertebral height, lumbar lordosis and local kyphosis Cobb angle immediately after operation and at the latest follow-up (P＜0.05) . [Conclusions] Three-pair pedicle screws with or without placement in the injured vertebrae do achieve satisfactory clinical outcomes for flexion-distraction thoracolumbar fractures. In contrast, the 3-pair pedicle screws with non-placement in the injured vertebrae is better than the 3-pair pedicle screws with placement in the injured vertebrae in correcting kyphosis and maintaining the anterior vertebral height.

Abstract:[Objective] To compare the clinical efficacy of two remnant preserved posterior cruciate ligament (PCL) reconstruction. [Methods] A retrospective study was conducted on 50 patients who received remnant preserved PCL reconstruction for PCL tear in our hos- pital from March 2012 to March 2020. According to the preoperative doctor-patient communication, 28 patients had the tibial tunnel locat- ed through the path under the axillary part of the anterior cruciate ligament (ACL) (subaxillary group) , while the other 22 patients were posi- tioned through the upper ACL and PCL gap path (conventional group). The perioperative period, follow- up and imaging data were com- pared between the two groups. [Results] All the patients in both groups got operation performed successfully, without complications such as injuries to vascular vessel and nerve during operation. The subaxillary group proved significantly less intraoperative blood loss than that in the conventional group (P＜0.05) . All patients were followed up for more than 2 years, and there was no significant difference in the time to return to full weight-bearing activity between the two groups (P＞0.05) . The Lysholm score, IKDC score, and knee flexion-extension range of motion (ROM) increased significantly (P＜0.05) , while VAS pain score and extent of posterior drawer test were significantly reduced in both groups over time (P＜0.05) . The subaxillary group proved significantly superior to the conventional group in terms of VAS pain score, Lysholm score, IKDC score, and posterior drawer test at 6 months and last follow-up (P＜0.05) . In terms of imaging, the subaxillary group got significantly better coronal position ratio (a/b) of the tibial tunnel intraarticular aperture than the conventional group (P＜0.05) , despite the fact that there was no significant difference in sagittal position ratio (c/d) between the two groups (P＞0.05) . The posterior tibial displace- ment in stress X-ray at 90° of knee flexion significantly reduced postoperatively in both group compared with that preoperatively (P＜0.05) , which in the subaxillary group was significantly less than the conventional group at 6 months and latest follow-up (P＜0.05) . [Conclusion] This arthroscopic remnant preserved PCL reconstruction by ACL subaxillary positioning of tibial tunnel is more conducive to accurate posi- tioning of the internal aperture of tibial bone tunnel, and does more effectively preserve the PCL remnant, and achieve better clinical outcome.

Abstract:[Objective] To evaluate the clinical efficacy of open reduction and internal fixation (ORIF) with preoperative simulation on 3D printed real model combined with Chinese herb soup for complex acetabular fractures. [Methods] From July 2019 to July 2021, a total of 86 patients received ORIF for complex acetabular fractures. According to doctor- patient communication, 43 patients had ORIF per- formed after preoperative simulation on 3D printed real pelvic model, while the remaining 43 patients received conventional ORIF. All pa- tients in both groups were administrated with Chinese herb soup, the Gushang Fuyuan Tang, after operation. The documents regarding to perioperative period, follow-up and images were compared between the two groups. [Results] All patients in both groups had ORIF finished successfully without serious complications. The 3D group proved significantly superior to the conventional group in terms of operation time, total incision length, intraoperative blood loss, postoperative walking time and hospital stay (P＜0.05) . In addition, the 3D group was also better than that of the conventional group in term of incision healing grade, but which was not statistically significant (P＞0.05) . All of them in both groups were followed up for more than 12 months, and the 3D group resumed full weight-bearing activity significantly earlier than the conventional group (P＜0.05) . The Mere D'Aubigne score, hip extension-flexion range of motion (ROM) and internal-external rotation ROM significantly increased, while VAS score for pain significantly decreased over time in both groups (P＜0.05) , which in the 3D group were significantly superior to the conventional group at all corresponding time points (P＜0.05) . Radiographically, the 3D group proved sig- nificantly superior to the conventional group in term of postoperative fracture reduction quality based on Matta's criteria (P＜0.05) , and frac- ture healing time on images as well (P＜0.05) . The T?nnis classification of hip degeneration deteriorated significantly over time in both groups (P＜0.05) , which in the 3D group were slightly eased compared with those in the conventional group at 6 months and the latest fol- low-up regardless of that the difference was not statistically significant (P＞0.05) . [Conclusion] This 3D printing simulation does consider-ably improve the efficiency and accuracy of ORIF for complex acetabular fractures, while the combined treatment with the Chinese herb soup is beneficial to postoperative rehabilitation.

Abstract:[Objective] To compare the clinical efficacy of robot-assisted (RA) versus traditional freehand (FH) percutaneous screw fix- ation for acetabular fractures. [Methods] A retrospective study was performed on 24 patients who had acetabular anterior column fracture fixed by percutaneous screws in our hospital from January 2018 to September 2021. According to the preoperative doctor-patient communi- cation, 12 patients received RA technique, while the remaining 12 patients underwent the traditional FH technique. The perioperative, fol- low- up and imaging consequences were compared between the two groups. [Results] All the patients in both groups had operation per- formed smoothly without neurovascular injury and other serious complications. Although there was no a significant difference in operation time between the two groups (P＞0.05) , the RA group proved significantly superior to the FH group in terms of screw placement time [(32.5± 7.2) min vs (57.6±11.9) min, P＜0.05] , guide pin adjustment times [(0.5±0.5) times vs (6.8±1.1) times, P＜0.05] , radiation exposure duration [(23.0± 7.6) sec vs (78.5 ±13.7) sec, P＜0.05] , intraoperative fluoroscopy times [(14.9±4.0) times vs (52.9±8.6) times, P＜0.05] and intraoper- ative blood loss [(32.0±9.0) ml vs (74.8±19.5) ml, P＜0.05] . However, there were no significant differences in incision healing grade and hos- pital stay between the two groups (P＞0.05) . All of them in both groups were followed up for more than 12 months, and there were no signifi- cant differences in time to return to walking and full weight-bearing activity between the two groups (P＞0.05) . As time went the VAS score for pain significantly decreased (P＜0.05) , while Majeed score significantly increased in both groups (P＜0.05) , which proved not statistical- ly significant between the two groups at any time points accordingly (P＞0.05) . Radiographically, no significant changes in Matta rating or implant position were observed in both groups at the last follow-up compared to those immediately postoperatively (P＞0.05) . In addition, there was no significant difference in the fracture healing time on images between the two groups (P＞0.05) . [Conclusion] Compared with the traditional freehand technique, the robot-assisted percutaneous anterograde acetabular screw fixation is more accurate, with less intra- operative radiation exposure, less tissue damage, and more stable clinical efficacy.

Abstract:[Objective] To evaluate the clinical outcome of cannulated screw combined with medial buttress plate (CSBP) for internalfixation of Pauwels type III femoral neck fractures. [Methods] A retrospective study was conducted on 72 patients who received open reduc-tion and internal fixation (ORIF) for Pauwels type Ⅲ femoral neck fractures from January 2015 to June 2021. According to the results ofpreoperative doctor- patient communication, 33 patients underwent CSBP, while the remaining 39 patients had conventional cannulatedscrew (CS) performed. The documents regarding perioperative period, follow-up and radiographs were compared between the two groups.[Results] All patients in both groups had corresponding surgical procedures performed smoothly without serious complications. Althoughthe CSBP group consumed significantly longer operation time, associated with significantly more intraoperative blood loss than the CS group(P＜0.05) , there were no significant differences between the two groups in terms of the total incision length, intraoperative fluoroscopytimes, guide needle placing times, ambulation time, incision healing, and hospital stay between the two groups (P＞0.05) . All patients werefollowed up for 12~24 months, and the CSBP group returned to full weight- bearing activity significantly earlier than the CS group (P＜0.05) . In the CSBP group, there was no bone nonunion or femoral head necrosis. Among the 39 cases in the CS group, there were 3 cases ofbone nonunion and 2 cases of femoral head necrosis. The incidence of late complications in the CSBP group was significantly lower thanthat in the CS group (P＜0.05) . The Harris score, hip extension -flexion range of motion (ROM) , and hip internal-external rotation ROM in-creased significantly over time postoperatively in both groups (P＜0.05) . The CSBP group proved significantly superior to the CS group interms of Harris score, hip extension- flexion ROM, and hip internal-external rotation ROM at all time points postoperatively (P＜0.05) .With respect of radiographic evaluation, the CSBP group was significantly superior to the the CS group in terms of Garden index, neckshaft angle, and Tonnis grade for hip degeneration at the latest follow-up (P＜0.05) . [Conclusion] This cannulated screw combined with me-dial buttress plate for internal fixation of Pauwels type Ⅲ femoral neck fractures does achieve considerably better clinical outcomes than the cannulated screw only.

Abstract:[Objective] To compare the clinical results of posterior triangle location technique versus conventional anteroposterior loca- tion method in arthroscopic posterior cruciate ligament (PCL) reconstruction. [Methods] A retrospective study was conducted on 60 pa- tients who received arthroscopic PCL reconstruction in our hospital. Among them, 32 patients were treated with posterior triangulation tech- nique (the posterior group) , and 28 patients were treated with conventional anteroposterior technique (the conventional group). The periop- erative, follow-up and imaging data of the two groups were compared. [Results] All the patients had PCL reconstruction performed success- fully without complications such as vascular and nerve injury. The posterior group proved significantly superior to the conventional group in terms of operation time, intraoperative fluoroscopy times (P＜0.05) . All the patients were followed up for (20.4±4.7) months, and the posteri- or group resumed full weight- bearing activity significantly earlier than the conventional group (P＜0.05) . The VAS, Lysholm and IKDC scores significantly improved in both groups at the last follow-up compared with those before surgery (P＜0.05) . Although there was no sig- nificant difference in VAS scores between 2 groups (P＞0.05) , the posterior group proved significantly superior to the conventional group in terms of Lysholm and IKDC scores at the latest follow up (P＜0.05) . Radiographically, there was no significant difference in tibial tunnel lo- cation (P＞0.05) . The posterior translation at 30° and 90° of knee flexion under stress on imaging was significantly reduced at the latest fol- low-up in both groups compared with those before operation (P＜0.05) , which were not statistically significant between the two groups at any matching time points (P＞0.05) . [Conclusion] The posterior triangle technique for tibial tunnel location in arthroscopic PCL reconstruc- tion has advantages of improving exposure of the surgical field, reducing the iatrogenic injury, saving the operation time, and preserving the residual posterior cruciate ligament and the meniscofemoral ligament, which is conducive to the functional recovery of the knee joint.

Abstract:[Objective] To evaluate the clinical efficacy of diamond- shaped (DS) versus inverted triangular (IT) cannulated screw placements for internal fixation of femoral neck fractures by meta-analysis. [Methods] Databases including CNKI, VIP, Wanfang Medical database, Sinomed, Pubmed, Embase, Web of Science, and the Cochrane Library were searched for all clinical studies on the comparison of the efficacy of DS versus IT cannulated screw placement for femoral neck fracture from the establishment of the database to March 2022. Af- ter literatures were screened by two researchers, the data were extracted with evaluation of the methodological quality to meet the inclusion and exclusion criteria. RevMan5.4 Software was used for meta-analysis. [Results] A total of 5 articles were enrolled in this study, involving 387 patients, including 178 patients in the DS group and 209 patients in the IT group. As results of the meta-analysis, the DS group had sig- nificantly greater intraoperative blood loss than the IT group (P＜0.05) , while the former had significantly higher Harris score at last followup than the latter (P＜0.05) . However, there were no significant differences in terms of operation time, fracture nonunion rate, femoral head necrosis rate, screw displacement rate and femoral neck shortening rate between the two groups (P＞0.05) . [Conclusion] Although the DS cannulated screw placement has considerably greater intraoperative blood loose, this screw placement configuration does achieve better out- come in term of Harris score than the inverted triangle configuration. There was no significant difference between the two configurations in fracture nonunion rate, femoral head necrosis rate, screw displacement rate, femoral neck shortening rate and other long-term complica- tions

Abstract:Due to complex anatomical structure of the pelvis and serious complications, the management of pelvic fracture is a compli- cated issue in orthopaedic practice. Different types of pelvic fractures have different treatment methods with considerable difficulty. The 3D printed real model might reveal the type and displacement of pelvic fractures clearly, which not only plays an important role in preoperative diagnosis and surgical planning of pelvic fractures, but also provides new ideas and methods for the personalized design of pelvic implants and the application of intraoperative navigation template. With the rapid development of 3D printing technology, the treatment of pelvic frac- tures has been improved to a great extent. In this review, we mainly summarize the progress on 3D printing use in the diagnosis and treat- ment of pelvic fractures.

Abstract:Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are among the most effective treatments for bone and joint diseases. Studies have proven that THA and TKA help patients correct deformities, reduce pain, and improve their quality of life. However, venous thrombus embolism (VTE) is a serious complication of the major joint replacements (MJR) . Pharmacological prophylaxis is essential to reduce thrombosis, of which aspirin (acetylsalicylic acid, ASA) not only has the advantages of low price, convenient administration, no need to blood monitoring, good tolerance and high safety, but also has the advantages of reducing the risk of periprosthetic infection, hetero- topic ossification and death. However, scholars are still uncertain whether ASA can replace other anticoagulants for thromboprophylaxis af- ter TJA. This paper reviews the application ASA in THA/TKA, and provides a reference for the selection of antithrombotic drugs after MJR.

Abstract:Total knee replacement (TKA) , an important surgical technique for end-stage osteoarthritis, has achieved good long-term results and prosthesis survival rate. Currently, cruciate retaining (CR) and posterior stabilized (PS) prostheses are the main types of TKA commonly used in clinical practice. However, the anterior cruciate ligament (ACL) must be removed during the implantation of both CR and PS prostheses in TKA. ACL is an important location of knee proprioception receptors. The removal of ACL will lead to changes in knee pro- prioception and motion mechanics, cause the subjective feelings inefficient. The bicruciate-retaining (BCR) knee can best simulate natural knee motion mechanics, has attracted renewed attention recently.

Abstract:[Objective] To explore the best lateral positioning angle to prevent deep pressure injury by a mechanical analysis with the three-dimensional finite element sacrococcygeal model at different lateral positioning angles. [Methods] The sacrococcygeal CT data of a healthy adult male volunteers in prone position were used to construct a three-dimensional finite element model, including skin adipose tis- sue, muscle tissue and bone at 0°, 15°, 30° and 45° lateral positioning angles. As boundary conditions were set and loads were applied, the Von Mises stress, shear stress and distribution characteristics of pressure to damage the sacrococcygeal soft tissues were measured. [Results] The Von Mises stress on the skin and adipose tissue were ranked in ascending order of 30° group ＜15° group ＜0° group ＜45 ° group with a statistically significant difference among them [(5.1±0.1) kPa, (5.6±0.2) kPa, (6.1 ± 0.1) kPa, (12.7±1.2) kPa, P＜0.001] , whereas the Von Mises stress on muscle tissue were down-up in order of 30° group ＜45° group ＜15° group ＜0° group, which was statistically significant [(17.6±0.8) kPa, (19.3±1.4) kPa, (20.6±0.5) kPa, (22.6±1.4) kPa, P＜0.001] . In addition, the shear stress on the skin and adipose tissue was in acending order as 30° group ＜15° group ＜0° group ＜45 ° group, which was statistically significant [(0.8±0.2) kPa, (0.9±0.1) kPa, (1.3± 0.2) kPa, (2.6±0.8) kPa, P＜0.001] , however, the shear stress on muscle tissue was ranked as 30° group ＜ 15° group ＜ 45° group ＜ 0 ° group with a statistically significant difference [(4.4±0.2) kPa, (4.4±0.2) kPa, (4.7±0.5) kPa, (5.1±0.3 ) kPa, P=0.02] . By comparison between tis- sues, both Von Mises stress and shear stress on the muscle tissue were significantly higher than those on the skin and adipose tissue under the 4 lateral positioning angles (P＜0.05) . [Conclusion] The Von Mises stress and shear stress on the sacrococcygeal soft tissue are the least at the lateral positioning angle of 30°, so it is recommended to use the lateral decubitus position at 30° to prevent the stress injury in the deep tissue.

Abstract:[Objective] To compare the mechanical properties of three kinds of internal fixation for femoral intertrochanteric fractures with lateral wall fracture. [Methods] The CT images of femur were obtained from a volunteer and processed by MIMICS14.0, Geomagic Stu- dio, CERO3.0, Hypermesh13.0 software to create the models of proximal femoral nail anti- rotation (PFNA) , PFNA enhanced by tension band and locking plate as internal fixation fore femoral intertrochanteric fractures with ruptured lateral wall respectively. The Von Mises stress and displacement of the implant and fractures were analyzed by using Abaqus6.12. [Results] All the Von Mises stresses of the three internal fixation modes were in descending order as the neck-trunk junction ＞ femoral head ＞ fracture site, with statistically significant dif- ferences (P＜0.05) . The Von Mises stress in femoral head was in descending order as PFNA ＞ PFNA-tension band ＞ locking plate with a statistically significant difference among them (P＜0.05) , whereas which proved not significantly different in the fracture site among the three groups (P＞0.05) , and were significantly ranked up-down in neck- trunk junction as PFNA ＞ Locking plate ＞ PFNA-tension band (P＜0.05) . Conversely, displacements of fracture ends were significantly arranged down- up in order of PNFA- tension band ＜ locking plate ＜ PFNA (P＜0.05) . [Conclusion] PFNA enhanced by tension band fixation does reduce the stress and displacement of femoral inter- trochanteric fracture complicated with lateral wall fracture, which is beneficial to the stability of fracture ends.

Abstract:[Objective] To introduce the surgical technique and preliminary clinical outcomes of total resection of schwannoma in lum- bar interforaminal area under a channel through Wiltse intermuscular space. [Methods] Two patients were treated by the abovementioned operation for lumbar interforaminal schwannoma. After location of the surgical approach and working channel according to the preoperative images, a working channel 14 mm in diameter was inserted through Wiltes muscle space to reach the outer surface of the laminae. The later- al laminae were partially resected, and the ligamentum yellow was removed, the responsible nerve roots and tumor membranous structures were fully exposed, the tumor envelope was cut longitudinally along the long axis of the tumor, and the tumor was totally excised along the boundary membrane. [Results] Both patients underwent complete tumor resection in one stage smoothly, got symptoms relief completely af- ter surgery, and resumed ambulation the next day. During the follow-up lasted for 17 months, no tumor recurrence or long-term surgical complications were found. [Conclusion] The surgical procedure by a channel through Wiltse intermuscular space does completely remove the lumbar interforaminal schwannoma in one stage, avoid postoperative spinal instability and paravertebral soft tissue injury.

Abstract:[Objective] To introduce the surgical technique and preliminary clinical results of Herbert screw via Ganz approach for fixa- tion of femoral head fracture. [Methods] Between January 2015 and September 2021, 10 patients underwent Herbert screw fixation of femo- ral head fractures via Ganz approach. After A 12~20 cm incision was made from about 5cm below the posterior superior iliac spine to the lateral midline of the thigh, longitudinal osteotomy of the greater trochanter was conducted with an oscillating saw from the posterior edge of the vastus lateralis, with 1.5cm greater trochanter bone block in thickness. The greater trochanter block with the gluteus medius and the vas- tus lateralis was pulled forward to expose the joint capsule, then the joint capsule was cut in a "Z" shape along the long axis of the femoral neck towards the lateral joint capsule. The femoral head was dislocated anterolaterally with flexion and external rotation maneuver. After de- bridement of the hip joint to remove blood clot the necrotic tissue, the fracture fragments of the femoral head were identified, reduced and fixed temporarily with Kirschner wires. Two to three countersunk cannulated screws with diameter of 2.4~3.5 mm were used to fix the femo- ral head bone fragments according to their size, with the screw tail buried under the cartilage. The femoral head was reduced by internal ro- tation and the greater trochanter osteotomy was fixed with two cortical screws. [Results] All patients had operation performed successfully with operation time of (139.5±30.5) min and intraoperative blood loss of (310.0±213.2) ml, and resumed full weight-bearing activity in 3~6 months after surgery. At 6 months after surgery, hip function was marked as excellent in 5 cases, good in 4 cases, and fair in 1 case accord- ing to Thompson-Epstein criteria. [Conclusion] Ganz approach for countersunk screw fixation of femoral head fracture dose fully expose the acetabulum and femoral head, and facilitate to reduce the fracture under direct vision, with low complication rate and good curative ef- fect.

Abstract:[Objective] To investigate the effect of tranexamic acid (TXA) on perioperative blood loss of thoracolumbar fracture and dis- location. [Methods] A retrospective study was performed on 63 patients who underwent surgical treatment for thoracolumbar fracture and dislocation in our hospital from January 2013 to June 2021, including 33 patients in the TXA group and 30 patients in the non-TXA group. The perioperative and blood test data of the two groups were compared. [Results] The TXA group proved significantly superior to the nonTXA group in terms of operation time, intraoperative blood loss and drainage 24 hours after operation (P＜0.05) . On the third day after oper- ation, no deep vein thrombosis was found by ultrasound in anyone of both groups. Compared with those preoperatively, the Hb, Hct and PLT significantly decreased (P＜0.05) , while the PT significantly increased (P＜0.05) , and APTT remained unchanged significantly 1 day postop- eratively in both groups (P＞0.05) . Although there was no significant difference in the above blood test parameters between the two groups before operation (P＞0.05) , the TXA group had significantly higher Hb, Hct and PLT than the non-TXA group 1 day postoperatively (P＜ 0.05) , whereas there was no significant difference in PT and APTT between the two groups (P＞0.05) . [Conclusion] Preoperative intrave- nous tranexamic acid does effectively reduce perioperative blood loss of thoracolumbar fracture and dislocation, which is safe and reliable.

Abstract:[Objective] To explore the clinical efficacy and safety of intra-articular injection of umbilical cord blood mononuclear cells (UCB-MNCs) for treatment of knee osteoarthritis (KOA) . [Methods] From February 2021 to September 2022, 30 patients received intraven- tricular injection of 2×108 (3 ml) UCB-MNCs twice with one month apart for early- and mid-stage KOA. The clinical and imaging data were evaluated. [Results] All the patients had the injection completed successfully, with the main adverse reactions of joint swelling and pain with- in a few days after injection, whereas which not affected functional activities of the joint. There were no significant changes in blood routine, erythrocyte sedimentation, C-reactive protein, liver function and kidney function before and after treatment. As time went during the followup lasted for 6 months, the VAS scores for pain and swelling, as well as WOMAC pain, stiffness, function, and overall scores significantly de- creased (P＜0.05) , while all KOOS subscores significantly increased (P＜0.05) . Radiographically, the Kellgren-Lawrence grades in the medi- al, lateral and patellofemoral compartments remained unchanged (P＞0.05) , the MRI Osteoarthritis Knee Score (MOAKS) of the medial com- partment was not changed either (P＞0.05) , while the MOAKS scores of the lateral and patellofemoral compartments significantly decreased 3 months after treatment compared with those before treatment (P＜0.05) . [Conclusion] Intra-articular injection of UCB-MNCs for KOA does effectively relieve pain and improve function in this trial.

Abstract:[Objective] To investigate the clinical outcomes of Ilizarov technique combined with hamstring lengthening for severe knee flexion deformities due to spastic cerebral palsy. [Methods] A retrospective study was done on 15 children who received the Ilizarov tech- nique and hamstring lengthening for bilateral severe knee flexion deformity due to spastic cerebral palsy in our hospital from August 2017 to April 2020 and the clinical consequences were evaluated. [Results] All patients had the surgical managements conducted successfully with- out serious complications such as vascular and nerve injury. Of them, 7 patients had hip and foot deformities corrected simultaneously, in- cluding hip adductor muscle release, obturator nerve constriction, Achilles tendon lengthening and gastrocnemius aponeurotomy. The frame was adjusted only within the first 28 days after operation and was carried up continuely. The duration of wearing the Ilizarov external fixator was 36~50 days, with an average of (41.1±3.5) days. All the patients were followed up for (1.6±0.3) years. The static flexion angle of the knee at 3 months after operation and at the last follow-up was significantly less than that before operation (P＜0.05) , while the passive range of mo- tion (ROM) and active ROM were significantly increased over time (P＜0.05) . The GMFCS was improved from grade Ⅳ preoperatively to grade Ⅲ at latest follow- up. According to Herzenberg's criteria, the clinical results were marked as excellent in 9 knees and good in 21 knees, with an excellent and good rate of 100.0%. [Conclusion] The Ilizarov technique combined with hamstring lengthening is an effective treatment for severe knee flexion deformity in spastic cerebral palsy.

Abstract:[Objective] To investigate the effect of pronator quadratus reattachment on the early clinical outcome of open reduction and internal fixation (ORIF) of distal radial fracture by Henry approach. [Methods] A retrospective study was conducted on 52 patients who re- ceived ORIF for AO type C distal radial fractures by Henry approach in our department from January 2018 to August 2019. According to the preoperative doctor-patient communication, 20 patients had the pronator quadratus reattached with suture (RA) following ORIF, while the other 32 patients remained the muscle in non-reattachment (NR) by suture. The perioperative and short-term follow-up data of the two groups were compared. [Results] All patients in both groups had the corresponding operations performed successfully, with no significant differences in terms of operation time, incision length, incision healing grade and hospital stay between the two groups (P＞0.05) . With time of the followed- up period lasted for more than 3 months after surgery, the VAS score for pain wrist flexion- extension range of motion (ROM) , radio- ulnar deviation ROM and forearm pronation- supination ROM significantly improved in both groups (P＜0.05) . The RA group proved significantly superior to the NR group in terms of VAS score at 1 week and 1 month postoperatively [(3.3±0.5) vs (5.3±1.3) , P＜ 0.001; (2.5±0.8) vs (3.2±1.0) , P=0.008] , as well as the forearm pronation-supination ROM 1 month after surgery [(90.3±15.9)° vs (79.6± 9.5)° , P=0.011] . According to Gartland-Werley criteria 3 months after surgery, the excellent and good rate of joint function was 18/2 (90.0%) in the RA group, while 24/4 (78.0%) in NR group, which was not statistically significant (P＞0.05) . [Conclusion] The pronator qua- dratus reattachment in open reduction internal fixation by Henry approach for distal radial fractures does effectively relieve postoperative pain and improve postoperative forearm rotational motion.

Abstract:[Objective] To investigate the clinical outcomes of percutaneous vertebroplasty (PVP) for severe osteoporotic vertebral com- pression fractures (sOVCF) . [Methods] A retrospective study was conducted on 39 patients who received PVP for sOVCF in our hospital from September 2018 to December 2020. The clinical and radiological data were evaluated. [Results] All patients were successfully operat- ed on with the mean operation time of (56.3±5.7) min and the mean bone cement injected of (5.2±2.2) ml. Bone cement leakage occurred in 9 cases (23.1%) , including paravertebral leakage in 3 cases and intervertebral leakage in 6 cases, all of which had no obvious clinical symptoms. All the patients were followed up for a mean of (12.7±3.8) months. With time elapsed preoperatively, 2 days postoperatively and the latest follow up, the VAS score [(6.5±0.2) , (2.4±0.8) , (2.5±0.8) , P＜0.05] and ODI score [(77.9±4.4) , (24.2±2.9) , (24.7±3.4) , P＜0.05] significantly reduced, while the JOA score [(14.3±2.7) , (21.3±1.9) , (20.7±1.7) , P＜0.05] significantly increased. Radiographically, the in- jured vertebral height [(6.7±1.7) mm, (16.5±4.0) mm, (14.4±3.3) mm, P＜0.05] increased significantly, while the local kyphotic Cobb angle [(24.1±13.0)°, (15.6±10.2)°, (19.0±1.5)°, P＜0.05] decreased significantly. [Conclusion] The PVP is safe and effective in the treatment of sOVCF. Preoperative position reduction and full filling of injured vertebral fissure are the key to successful treatment.

Abstract:[Objective] To investigate the clinical outcomes of cannulated screw fixation of distal tibial epiphysis fracture in children. [Methods] A retrospective study was performed on 70 children who had distal tibial epiphysis fractures fixed with cannulated screws follow- ing closed or open reduction from December 2018 to December 2021, and the clinical and imaging data were evaluated. [Results] All the 70 patients were operated on successfully without complications such as vascular and nerve injury during the operation. The follow-up peri- od lasted for (8.4±2.1) months on an average. Compared with those before operation, and the VAS score at 3 months and the last time signifi- cantly decreased [(5.9±1.0) , (1.3±0.3) , (1.2±0.2) , P＜0.001] , while AOFAS score [(34.8 ±7.92) , (82.7±8.9) , (94.1±4.1) , P＜0.001] , an- kle dorsal-plantar flexion range of motion (ROM) [(36.5±4.3)°, (63.8±10.4)°, (74.9±11.5)°, P＜0.001] and inversion-eversion ROM [(30.7± 6.9)°, (54.8±8.9)°, (65.8±9.0)°, P＜0.001] significantly increased. Radiographically, the fracture alignment was significantly improved after surgery compared to before surgery (P＜0.05) , additionally, the mLDTA angle and aADTA angle significantly improved postoperatively (P＜ 0.05) . Bony healing of the fractures was observed in all patients at about 10 weeks. [Conclusion] The cannulated screw fixation is a reli- able treatment for distal tibial epiphyseal fractures in children with satisfactory short-term outcomes.