operation (

>0.05). MSOA score increased from 3.74±2.54 before operation to 7.04±2.51 at 24 months after opertaion (

<0.05).

Treatment of chronic lateral ankle instability with reconstruction of lateral ligament complex with single-tunnel pullout structure fixation could provide better tendon and bone healing conditions, improve surgical safety and could achieve satisfactory clinical outcomes.

Treatment of chronic lateral ankle instability with reconstruction of lateral ligament complex with single-tunnel pullout structure fixation could provide better tendon and bone healing conditions, improve surgical safety and could achieve satisfactory clinical outcomes.

To explore biomechanical characteristics of minimally invasive different screw fixations in treating Sanders typeⅡcalcaneal fractures.

Dicom data of calcaneus by CT scan were input into Mimics 21.0 software and Ansys15.0 software to construct three-dimensional finite element digital model of calcaneus;this model was input into UG NX 10.0 software, and calcaneus was cut according to Sanders classification to establish Sanders typeⅡ calcaneus model with posterior articular surface collapse;then simulated minimally invasive screw internal fixation after calcaneal fracturea screw from posterior articular surface was used to outside-in fix sustentaculum tali, other 4 screws were used to fix calcaneus by different methods through calcaneal tuberosity, and 4 different calcaneal models were obtained. Under the same conditions, 4 types of internal fixation models were loaded respectively, and nonlinear finite element analysis was performed to calculate the stress distribution of different internal fixation models.

Under the same condition of loading, the model 3 had smaller displacement value, maximum calcaneus displacement value and maximum equivalent stress value of the screw than other three internal fixation models, and the stress was more dispersed.

In minimally invasive screw internal fixation of calcaneus fracture, after 1 sustentaculum tali screw fixation, 2 screws crossed fix posterior articular surface from calcaneal tuberosity, 2 screws fix parallelly calcaneocuboid joint from calcaneal tuberosity are more suitable for biomechanical requirements, and could provide basic theory for clinical treatment.

In minimally invasive screw internal fixation of calcaneus fracture, after 1 sustentaculum tali screw fixation, 2 screws crossed fix posterior articular surface from calcaneal tuberosity, 2 screws fix parallelly calcaneocuboid joint from calcaneal tuberosity are more suitable for biomechanical requirements, and could provide basic theory for clinical treatment.

To analyze effect of accordion technique on bone mineralization of extended bone segment in treating tibial bone defect with bone transport.

From May 2017 to October 2019, 22 patients with tibial bone defects were treated with Ilizarov bone-transport technique, and divided into two groups after bone-transport was completed, 11 patients in each group. check details In observation group, there were 9 males and 2 females aged from 20 to 60 years old with an average of (42.6± 13.3) years old;the length of bone defect ranged from 3 to 13 cm with an average of(6.4±2.6) cm;2 patients were suffered from upper tibial bone defects, 3 patients were middle and 6 patients were lower;patients were treated with accordion technique for 35 days. In control group, there were 10 males and 1 female aged from 41 to 60 years old with an average of (51.6±6.4) years old;the length of bone defect ranged from 3 to 10.7 cm with an average of (6.6±2.5) cm;1 patient was suffered from upper tibial bone defects, 3 patients were middle and 7 patientslent results, and 1 good in observation group; while 9 patients got excellent results, 2 good in control group;and there was no differences between two groups (

=-0.607,

= 0.544).

Accordion technique and locking external fixator mineralization in prolonging bone segment healing after bone-transport have the equal clinical effect, while the accordion technique could significantly accelerate the growth rate of HAP and shorten the mineralization time and healing time.

Accordion technique and locking external fixator mineralization in prolonging bone segment healing after bone-transport have the equal clinical effect, while the accordion technique could significantly accelerate the growth rate of HAP and shorten the mineralization time and healing time.

To study mechanism of improvement of stress concentration on patellofemoral joint by stiletto needle releasing lateral patellar retinaculum guided by the theory of Jinshugu() and based on the finite element model of knee joint. and to elucidate the biomechanical mechanism of stiletto needle releasing changing patellar trajectory and reducing patellofemoral joint pressure.

CT data of knee joint from a normal male (aged 29, heighted 171 cm, weighted 58 kg) was selected. Starting with construction of three-dimensional model of knee joint by using finite element software, the finite element model of knee joint with complete tendonand bone structures were established through several steps, such as geometric reconstruction, reverse engineering, meshing, material assignment and loading analysis. The loading condition was set as 500 N load on knee joint, and the average tensile stress of quadriceps femoris tendon was about 200 N. To simulate the release of lateral patellar retinaculum by stiletto needle at 30 andith stiletto needle could effectively alleviate the stress concentration of patellofemoral joint and reduce local stress peak value, which it is helpful to improve patellar trajectory and make stress distribution more uniform.

To evaluate the clinical effects of tranexamic acid in arthroscope for femoroacetabular impingement.

Totally 34 patients (34 hips) with femoroacetabular impingement underwent hip arthroscopy from June 2016 to December 2018, were randomly divided into two groups named as tranexamic acid group and control group, 17 patients in each group. In TXA group, there were 10 males and 7 females, aged from 20 to 49 years old with an average of (32.1±7.6) years old;15 mg/kg TXA was intravenous drops before operation incision performed at 10 min. In control group, there were 11 males and 6 females, aged from 20 to 49 years old with an average of (30.9±6.2) years old;100 ml normal saline was intravenous drops before operation incision performed at 10 min. Introopertaive and total bloodloss between two groups were compared. Visual analogue scale (VAS) at 3 and 7 days after opertaion were used to evaluate pain relief of hip joint. Modified Harris Hip Score(mHHS) of hip joint at 3, 6, 9 and 12 weeks after oeprtaion were applied to evaluate clinical effects.