Objective To evaluate the clinical outcome of lateral malleolar's anatomical hook-plate in treating ankle fracture including distal fibular fracture. Methods Nineteen patients of ankle fracture including distal fibular fracture were treated from January 2006 to January 2009. There were 12 males and 7 females with an average age of 36 years (range, 18-72 years). The fractures were classified by Danis-Weber system. There were A type in 8 cases, B type in 11 cases. The average time of duration between injury and operation was 6 days (ranged from 6 hours to 16 days). The distal fibular fracture were treated with lateral malleolar's anatomical hook-plate. The medial malleolus was fixed with cancellous bone screw. The posterior malleolus was fixed with screw or plate according to the pattern of fracture. Results The mean follow-up period was 18.8 months with a range from 6 to 32 months. No obvious fracture line could be seen on the radiographs 4-6 weeks after operation. Bone healing was achieved in 10 cases 12 weeks after operation and in 9 cases 20 weeks after operation. All surgical incisions healed adequately. There were no instances of infection, instability of ankle and other complications. According to Mazur ankle joint scoring scale system, the fiual result was scored from 67 to 92 (average 86.3). There were excellent in 12 cases, good in 4, fair in 2,and poor in 1 case. The excellent and good rate was 84.2%. Conclusion The lateral malleolar's anatomical hook-plate represents a definite biomechanical superiority in treating fracture of the external malleolus, with advantage of restoring anatomic structure, joint activity effectively and firm fixation.

Objective To investigate the clinical effects of tibiotalocalcaneal arthrodesis (TTCA) using a retrograde intramedullary nail with a valgus curve.Methods At our department,22 patients underwent TTCA using a retrograde intramedullary nail with a valgus curve from June 2009 to January 2014 and were available for complete follow-up.They were 12 men and 10 women,aged from 46 to 79 years (average,62.2 years).There were 3 cases of primary ankle osteoarthritis,9 ones of traumatic arthritis,one of ankle arthritis secondary to severe talar avascular necrosis,3 ones of progressive subtalar arthritis following failed ankle replacement,5 ones of progressive subtalar arthritis following failed ankle arthrodesis,and one of arthritis secondary to equinovarus.The outcome measurements included the American Foot and Ankle Society (AOFAS) ankle-hindfoot scale,EQ-5DTM functional score,radiologic assessment and clinical examination.Results The mean follow-up was 21.3 months (range,from 14 to 38 months).A plantigrade foot and bony union were achieved in all the patients after a mean time of 3.9 months (range,from 2.4 to 6.2 months).Postoperative radiologic results showed a good hindfoot alignment in all the patients.Superficial infection occurred in one patient and loosening of the distal screw in another who asked for removal.The mean postoperative EQ-5DTM functional score and AOFAS ankle-hindfoot score were 69.3 (range,from 20 to 90) and 69.9 (range,from 45 to 85),respectively.Conclusion TTCA using a retrograde curved intramedullary nail may lead to solid fusion and good hindfoot alignment.

Objective:To investigate the effect of robot-assisted percutaneous retrograde screw fixation in the treatment of acetabular fractures involving the posterior column.Methods:A retrospective case series study was conducted to analyze the clinical data of 13 patients with acetabular fractures involving the posterior column admitted to Wuhan Fourth Hospital from January 2019 to December 2020. There were 8 males and 5 females，aged 62-78 years［（69.7±1.5）years］. According to Judet-Letournel classification，fractures involved the posterior column in 4 patients，anterior column plus posterior semi-transverse column in 3 and double column in 6. According to AO classification，type 62-A2.1 was found in 2 patients，62-A2.2 in 2，62-B3 in 3 and 62-C in 6. All patients were treated with retrograde percutaneous screws assisted by orthopaedic surgery robot. The operation time，intraoperative blood loss，length of hospital stay and time of bone healing were recorded. The incision healing and complications were detected. Matta reduction standard was used to evaluate the fracture reduction quality at 2 days after operation，and Majeed function score was used to evaluate the functional recovery preoperatively，at 3 months after operation and at 6 months after operation.Results:All patients were followed up for 6-12 months［（9.3±1.7）months］. The operation time was 1.1-1.5 hours［（1.3±0.2）hours］. The intraoperative blood loss was 110-200 ml［（161.3±21.1）ml］. The length of hospital stay was 8-13 days［（10.7±1.3）days］. The time of bone healing was 14-18 weeks［（15.4±1.1）weeks］. All incisions were healed by first intention. One patient with sciatic nerve injury was treated with mecobalamin and recovered 3 months later. One patient with advanced heterotopic ossification had no obvious clinical symptoms. All patients had no complications such as incision infection，deep venous thrombosis of lower limbs，fat embolism，screw penetration into hip joint，fracture displacement after failure of internal fixation，traumatic arthritis，or necrosis of femoral head，etc. According to Matta reduction standard，there were 10 patients with anatomical reduction and 3 with satisfactory reduction. Majeed function score was（15.0±1.3）points before operation，（76.5±2.0）points at 3 months after operation and（85.1±1.9）points at 6 months after operation（ P<0.01），and there were 9 patients with excellent results，2 with good results and 2 with fair results，showing the excellent and good rate of 85%. Conclusion:For acetabular fractures involving the posterior column，robot-assisted percutaneous retrograde screw fixation has advantages of less surgical trauma，higher fracture healing rate，fewer complications，satisfactory anatomical reduction and good functional recovery.

Objective:To investigate the accuracy of infra-acetabular screw implantation assisted by a 3D-printed personalized screw guide in vitro. Methods:The imaging data were collected of the 10 patients with acetabular fracture involving the anterior column who had been treated at Department of Orthopaedics, The Fourth Hospital of Wuhan from June 2015 to October 2021. There were 8 males and 2 females, with an average age of (42.6±2.1) years. According to the Letournel-Judet classification, there were 2 anterior column fractures, 4 anterior column + posterior semi-transverse fractures, 3 double column fractures, and 1 T-shaped fracture. The thin-slice CT scan data of the patients’ pelves were imported into the E3D software to generate digital 3D fracture models in which fracture reduction and post-reduction were simulated and personalized screw guides for infra-acetabular screw implantation were generated. After the above models were printed by a 3D printer, the fracture models were reduced in vitro and the infra-acetabular screws were implanted assisted by the personalized guide on the affected and healthy acetabulum models. After operation, the printed models were scanned by CT again, and the CT data were imported into the E3D software again to generate the postoperative digital 3D models. The position relationships were observed between the screws and the cortex around the corridor on the postoperative CT scan images. The consistency of the position parameters was compared between pre- and post-operation for each screw in the digital models. Results:Ten personalized screw guides were generalized respectively for the affected and healthy sides of the 10 patients in this group. Anatomical reduction was achieved in vitro in all the 3D printed fracture models. A total of 20 infra-acetabular screws were implanted with the assistance by the screw guide. According to the Andrew's CT grading for pedicle screw positions, 19 infra-acetabular screws were rated as grade Ⅰ and 1 was rated as grade Ⅱ. The linear distance from the midpoint of the pubic symphysis to the point of insertion, and the angles between the axis of the screw and the horizontal, sagittal and coronal planes on the health side before operation were respectively (60.65±5.55) mm, 23.96°±5.59°),2.88 °±1.25°, and 65.06°±5.48°, showing insignificant differences from the postoperative values [(60.91±5.73) mm, 24.00°±6.15°, 3.20°±1.13°, and 65.74°±5.57°] ( P>0.05); the above screw position parameters on the affected side before operation were respectively (60.76±4.41) mm, 24.77°±2.97°, 3.06° (2.66°, 3.68°), and 63.70° (62.70°, 65.60°), showing insignificant differences from the postoperative values [(60.71±4.56) mm, 24.67°±2.73°, 3.04° (2.64°, 3.51°), and 64.40°(63.20°, 65.90°)] ( P>0.05). Conclusion:In the models in vitro, implantation of infra-acetabular screws assisted by a 3D printed personalized screw guide can be highly accurate, owing to insignificant differences in all the position parameters between the simulated operations and the operations in vitro.

Objective To evaluate euthyphoria reduction combined with percutaneous iliosacral screw fixation in the treatment of irreducible sacroiliac dislocation.Methods From March 2012 to May 2015,29 patients with irreducible sacroiliac dislocation were treated using euthyphoria reduction followed by percutaneous iliosacral screw fixation.They were 18 men and 11 women,aged from 25 to 68 years (average,37.9 years).According to the Tile classification,there were 7 cases of type Cl,9 cases of type C2,and 13 cases of type C3.The intervals from injury to surgery ranged from 6 to 32 days (average,11.3 days).Results The operation time for this cohort ranged from 40 to 125 minutes (average,76.2 minutes).The intraoperative bleeding ranged from 50 to 360 mL (average,148.6 mL).Their follow-ups ranged from 24 to 41 months (average,28.9 months).According to the Matta criteria for reduction,20 cases were rated as excellent and 9 as good,yielding an excellent to good rate of 100％.Their Majeed scores at the final follow-up averaged 90.1 points (range,from 67 to 100 points),giving 20 excellent,7 good and 2 fair cases (with an excellent to good rate of 93.1％).No screw loosening or lameness of the affected limb was observed during follow-ups.Conclusions Euthyphoria reduction combined with percutaneous iliosacral screw fixation can lead to satisfactory outcomes in the treatment of irreducible sacroiliac dislocation.Additionally it may improve operative safety.

Objective To compare the biomechanical performance of Kangli hollow screws with sliding compression locking plate system (KHS) and conventional cannulated lag screws for fixation of type Pauwels Ⅲ femoral neck fracture.Methods 7 cadaveric femurs were selected,vertical fractures (Pauwels Ⅲ fracture,at 70° to the horizontal) were artificially conducted in these cadaveric proximal femurs by an orthopaedic surgeon and fixed by KHS screws with plate system or conventional cannulated lag screws.Samples were positioned at 75° of the femoral shaft to the horizontal,embedded in the mould and fixed in the experimental console.Optical sensors were set at the femoral neck around the osteotomy line.Then the loading were input in the vertical,horizontal lateral direction and rotating direction around the femoral neck axis,the maximal and minimal values between the fractured fragments and the corresponding values of the loading were recorded.The values of stiffness in three directions were calculated and compared.The CT data of the left femur of a 25 year-old healthy male volunteer was input into the co(m)esponding software and vertical femoral neck fracture model was generated.Two finite element analysis models were obtained after the fracture being fixed using these two different implants,and the Von Mises stress distribution on the femur,implants and the interface between the fractured fragments and the relative motion between the fractured fragments were compared.Results In the vertical,horizontal lateral direction and rotating direction around the femoral neck axis,the stiffness of the KHS were 3 904±1 148 N/mm,4 324±1 234 N/mm and 11.45±4.95 N · m/° respectively,higher than those of the CSs method with the values of 3 020±1 150 N/mm,3 020± 854 N/mm.and 6.53±4.83 N· m/° respectively.The differences between the two groups were statistically significant (t=2.7194,4.7694 and 2.9424;P=0.0347,0.0050 and 0.0423).In the finite element analysis test,the maximal Von Mises stress values distributing on the femur and the screws in the KHS group were 40.1 MPa and 126.4 MPa,and those in the CSs group were 98.1 MPa and 145.5 MPa respectively,and both values of the former were lower than the latter.But the Von Mises stress value on the interface between the fractured fragments in the KHS group was 14.37 MPa,which was much higher than that in the CSs groupwhich was 9.39 MPa.The gap at the fracture site of the CSs fixation model was dramatically larger than that of KHS fixation model.Conclusion The KHS screws and plate system could provide better immobilization effect for vertical femoral neck fracture compared to the cannulated lag screws.The risk of the screws failure was lower and the fracture union would be easier to obtained by the fixation of KHS screws with plate system.

Objective:To evaluate antegrade interlocking intramedullary nails combined with less invasive stabilization system (LISS) in the treatment of femoral fractures (Lambiris type Ⅲ or Ⅳ).Methods:The clinical data of 27 patients were retrospectively analyzed who had been treated for femoral fractures of Lambiris type Ⅲ or Ⅳ at Department of Orthopedic Surgery, Wuhan Fourth Hospital from February 2015 to May 2019. They were 21 males and 6 females, aged from 22 to 57 years (average, 41.3 years). According to the Lambiris classification, 24 cases were classified as type Ⅲ (17 as type Ⅲa, 5 as type Ⅲb and 2 as type Ⅲc) and 3 cases as type Ⅳ. The time from injury to operation ranged from 2 to 9 days (average, 4.3 days). All the fractures were fixated with anterograde femoral interlocking nails and femoral LISS. Recorded were operation time, intra-operative blood loss, hospital stay, bone healing time, and Harris hip score, Hospital for Special Surgery (HSS) knee score and complications at the final follow-up.Results:In this cohort, operation time averaged 2.1 h (from 1.8 to 2.5 h), intraoperative blood loss 361 mL (from 310 to 480 mL), and hospital stay 15.1 d (from 11 to 18 d). All the 27 patients were followed up for 13 to 38 months (average, 25.3 months) after operation. All the fractures united well after an average duration of 29.2 weeks (from 28 to 36 weeks). By the Harris hip scores at the final follow-up, the hip function was evaluated as excellent in 18 cases, as good in 6 and as acceptable in 3, giving an excellent and good rate of 88.9%(24/27); by the HSS knee scores at the final follow-up, the knee function was excellent in 16 cases, good in 7 and acceptable in 4, giving an excellent and good rate of 85.2%(23/27). Follow-ups observed no fracture nonunion, malunion, refracture, internal fixation failure or other complications.Conclusion:In the treatment of femoral fractures of Lambiris type Ⅲ or Ⅳ, antegrade interlocking intramedullary nails combined with LISS has advantages of rigid fixation, a high rate of fracture union, limited complications, and good functional recovery.

Objective: To evaluate Kangli hollow screws with sliding compression locking plate system (KHS) in the treatment of femoral neck fractures. Methods: From February 2015 to October 2016, 47 femoral neck fractures were treated at Department of Orthopaedics, Wuhan Fourth Hospital, Wuhan Puai Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology. They were 30 men and 17 women, aged from 26 to 68 years (average, 43.5 years). According to the Pauwels classification, there were 24 cases of type Ⅰ, 16 cases of type Ⅱ and 7 cases of type Ⅲ; according to the Garden classification, there were 23 cases of type Ⅱ, 19 cases of type Ⅲ and 5 cases of type Ⅳ. All the fractures were immobilized with KHS after closed reduction or open reduction (3 cases). The fracture union time, femoral head necrosis and femoral neck shortening were observed after operation. The Harris scores were used to evaluate therapeutic effects at the final follow-up. Results: All the patients were followed up for an average of 29.7 months (from 22 to 39 months). All the fractures obtained solid bony union after 9 to 15 weeks(average, 12.2 weeks). Femoral head necrosis occurred in one case (2.1%). Femoral neck shortening ≤ 5 mm was observed in 6 cases and femoral neck shortening >5 mm <10 mm in 2 cases, giving a total shortening rate of 17.0%. The Harris scores at the final follow-up ranged from 77 to 98 points, averaging 92.2 points. There were 42 excellent, 3 good and 2 moderate cases, giving an excellent and good rate of 95.7%. Conclusion KHS can lead to excellent therapeutic effects in the treatment of femoral neck fractures.