Review on the origin of knee valgus deformity / 中华骨科杂志

The sources of common knee valgus deformities were classified in order to better plan the orthopedic methods, matching prostheses and soft tissue repair of knee valgus deformities.Based on the analysis of typical clinical cases and the operability of classification standards in practical clinical practice, it is of great significance to establish a reasonable morphological classification of knee valgus deformity, in order to grasp the characteristics and patterns of the onset of valgus deformity. According to the origin of the deformity and the tension of the medial and lateral collateral ligaments, the classification of the genu valgus deformity can be divided into the classification of the traditional Genu valgum deformity origin and the classification of the new Genu valgum deformity origin. Although both of them highlight the skeletal characteristics and soft tissue conditions of the valgus deformity, they are quite different. Traditional classification is based on femoral tibial angle, valgus angle, etc; The new classification is divided into mechanical angle, anatomical angle, distal condylar angle, etc. The origin of Genu valgum deformity is generally complex. The traditional classification cannot fully reflect the origin of valgus deformity and the tension state of soft tissue. The new classification, especially based on the classification of anatomical angle valgus deformity, can not only reflect the morphological and anatomical details of knee valgus deformity, but also reflect the tension state of the medial and lateral collateral ligaments and local soft tissue stress state that determine the stability of the knee joint. At present, the commonly used surgical methods for valgus deformity of the knee include periarticular osteotomy of the knee and total knee Joint replacement. The former focuses on correcting extraarticular deformity without over repairing ligaments, and the latter focuses on force line correction, which is the final treatment for terminal valgus deformity. The application of digital technology in clinical orthopedics can improve the accuracy of implant placement. Implant placement needs to be based on the patient's bone characteristics and degree of deformity. For patients with severe deformity, the application of digital technology can improve the accuracy of implant placement and assist in the treatment of knee valgus deformity.

The predictive function and application value of hip fracture scoring system in the elderly / 中华骨科杂志

Objective:To establish a risk assessment system focusing on surgical and anesthesian-related indicators for the incidence of complications and mortality of hip fracture surgery in senile patients, and to evaluate its prediction accuracy, sensitivity and specificity.Methods:From January 2020 to February 2021, a total of 1 086 elderly patients (493 males and 593 females) aged 76±5 years (ranging from 60 to 94 years) underwent hip fracture surgery in Tianjin Hospital were collected. A total of 543 patients were randomly selected for the establishment of the hip fracture scoring system in senile patients, including 253 males and 290 females, aged 75±6 years (ranging from 60 to 92 years). With the preoperative physiological factor score and surgical risk factor score as independent variables and the occurrence of complications and death as dependent variables, binary logistic regression analysis was performed to establish a surgical risk scoring system for hip fracture in senile patients. The remaining 543 patients, including 240 males and 303 females, aged 74±7 years (range 60-94 years), their data were used to compare AUC, sensitivity, specificity, and compliance of the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM), Daping orthopedics operative risk scoring system for senile patient (DORSSSP), and our surgical risk scoring system for hip fracture in senile patients through receiver operating characteristic (ROC) curves, and to compare the predictive value of these systems for complication incidence and mortality.Results:The predictive model equation of the elderly hip fracture scoring system is: ln R1/ (1- R1) =-7.13+0.112× PS+0.148× OS; ln R2/ (1- R2) =-6.14+0.124× PS+0.136× OS; [ R1 is the incidence of complications, R2 is the mortality, PS (physiology score) is the score of preoperative physiological factors, and OS (operation score) is the score of surgical risk factors]. Among the 543 patients whose data were used to compared with the hip fracture scoring system, POSSUM and DORSSSP, 72 actually developed complications and 36 died. The complication rate predicted by surgical risk scoring system for hip fracture in senile patients was 12.05%±6.34% (range 6.18%-61.29%), and 64 cases were predicted to have complications. The predicted mortality was 6.05%±3.26% (range 2.45%-58.36%), and 29 cases were predicted to die. The complication rate predicted by POSSUM was 25.36%±13.95% (range 9.16%-76.34%), and 126 cases were predicted to have complications. The predicted mortality rate was 10.46%±5.31% (range 6.23%-59.34%), and 54 deaths were predicted. The predicted complication rate of DORSSSP was 19.34%±9.67% (range 8.36%-70.85%), and 99 cases were predicted to have complications. The predicted mortality was 10.12%±5.16% (range 7.35%-57.54%), and 52 deaths were predicted. In predicting the incidence of complications, the AUC of surgical risk scoring system for hip fracture in senile patients, POSSUM and DORSSSP were 0.95, 0.82 and 0.75, the sensitivity was 0.89, 0.83 and 0.85, the specificity was 0.80, 0.86 and 0.92, and the compliance rate was 0.94, 0.93 and 0.94, respectively. In the prediction of mortality, the AUC of surgical risk scoring system for hip fracture in senile patients, POSSUM and DORSSSP were 0.87, 0.67 and 0.71, the sensitivity was 0.85, 0.69 and 0.75, the specificity was 0.73, 0.94, 0.95, and the compliance rate was 0.94, 0.93 and 0.94, respectively. Conclusion:Compared with POSSUM and DORSSSP, hip fracture scoring system in elderly patients has improved its ability to predict surgical risk, and can accurately predict the incidence of complications and mortality in elderly patients undergoing hip surgery.

Research progress in application of artificial intelligence to intraoperative navigation assisted by an orthopedic robot / 中华创伤骨科杂志

Orthopedic robots, as intelligent medical devices, have achieved good outcomes in clinical application in some orthopedic surgeries. Artificial intelligence (AI) has played an important role in the development of orthopedic robots due to its powerful capabilities of information processing and decision-making. The developing trends of orthopedic robotics are automation and intelligentization. Since AI has demonstrated great advantages in preoperative planning, an increasing number of researchers have been devoted to AI application in intraoperative navigation by an orthopedic robot. This paper outlines the exploratory efforts in applying AI technology to the intraoperative navigation assisted by an orthopedic robot, describes the advantages of AI in improving accuracy and reducing radiation, and forecasts research prospects in application of AI technology to orthopedic robots based on the current situation.

Kinematics and Plantar Pressure Analysis of Varus Femur and Varus Tibia / 医用生物力学

Objective To compare the differences in kinematic parameters and plantar pressures for two types of knee varus with tibial and femoral origins in gait analysis, so as to provide biomechanical theoretical basis for different types of genu varus. Methods Twenty-six patients with unilateral knee osteoarthritis (KOA) varus genu were enrolled, with 13 from femoral and 13 from tibial sources. Using Noraxon MyoMotion three-dimensional (3D) motion capture system and Footscan plantar pressure test system, the gait of the subjects during natural walking was measured, the temporal and spatial parameters of the gait, the kinematics parameters of lower limb joints and plantar pressures were collected, to make comparative analysis between the two groups. Results The range of knee flexion and extension of tibial varus, the peak of hip abduction, the range of motion (ROM) of hip adduction and abduction and the peak of ankle pronation were larger than those of femoral lateral genu varus. The peak of knee flexion and hip adduction was smaller than that of femoral lateral genu varus. Compared with femoral varus, subjects with tibial varus had increased stress time and peak pressure on the plantar of the 4th and 5th metatarsals (P<0.05). In the 3rd metatarsal region, the impulse of healthy femoral limb was greater than that of healthy limb with tibial deformity. While in the medial calcaneal region, the impulse of healthy femoral limb was smaller (P<0.05). Conclusions There are some differences in kinematic parameters and plantar pressures between two different types of unilateral genu varus patients. The results of this study are helpful to understand the abnormal gait caused by genu varus, and provide reliable reference for postoperative rehabilitation and limb exercise for different types of genu varus.

Stress Distributions Affected by Different Filling Blocks in Medial Opening Wedge High Tibial Osteotomy / 医用生物力学

Objective To analyze the influence from material and size of the filling block on stress distributions of the tibial osteotomy model. Methods The filling blocks with three different materials (iliac bone, cancellous bone and polyetheretherketone (PEEK)) and five different sizes were established and implanted to the tibial osteotomy models, respectively. The mechanical loads were applied on the model, the stress distribution and edge displacement of the model were analyzed. Results For three kinds of materials, the stress at proximal end of the tibia and the plate, as well as edge displacement in the model implanted with filling block by iliac bone material were lower than those of the cancellous bone and PEEK, but the filling block by iliac bone material had the highest stress. When the filling blocks with different sizes were implanted in osteotomy space, the stress distribution on each part of the tibial osteotomy and edge displacement were different. Especially when the width of the filling block was reduced from 30 mm to 10 mm, the peak stress of the proximal tibia, steel plate and filling block was increased by 49. 3% , 92. 7% and 54. 4% on average. Conclusions Different filling block parameters will affect the stress distribution in different parts of the tibial osteotomy. The research results provide the theoretical basis for parameter selection of the tibial osteotomy filling block in clinic.

Application of automatic injection device based on automatic hemostasis in injection of radiopharmaceutical bolus injection / 生物医学工程学杂志

In clinical practice, radiopharmaceutical dynamic imaging technology requires the bolus injection method to complete injection. Due to the failure rate and radiation damage of manual injection, even experienced technicians still bear a lot of psychological burden. This study combined the advantages and disadvantages of various manual injection modes to develop the radiopharmaceutical bolus injector, and explored the application of automatic injection in the field of bolus injection from four aspects: radiation protection, occlusion response, sterility of injection process and effect of bolus injection. Compared with the current mainstream manual injection method, the bolus manufactured by the radiopharmaceutical bolus injector based on the automatic hemostasis method had a narrower full width at half maximum and better repeatability. At the same time, radiopharmaceutical bolus injector had reduced the radiation dose of the technician's palm by 98.8%, and ensured more efficient vein occlusion recognition performance and sterility of the entire injection process. The radiopharmaceutical bolus injector based on automatic hemostasis has application potential in improving the effect and repeatability of bolus injection.

Research progress in influence of microstructure on performance of triply-periodic minimal surface bone scaffolds / 中国修复重建外科杂志

OBJECTIVE@#To summarize the influence of microstructure on performance of triply-periodic minimal surface (TPMS) bone scaffolds.@*METHODS@#The relevant literature on the microstructure of TPMS bone scaffolds both domestically and internationally in recent years was widely reviewed, and the research progress in the imfluence of microstructure on the performance of bone scaffolds was summarized.@*RESULTS@#The microstructure characteristics of TPMS bone scaffolds, such as pore shape, porosity, pore size, curvature, specific surface area, and tortuosity, exert a profound influence on bone scaffold performance. By finely adjusting the above parameters, it becomes feasible to substantially optimize the structural mechanical characteristics of the scaffold, thereby effectively preempting the occurrence of stress shielding phenomena. Concurrently, the manipulation of these parameters can also optimize the scaffold's biological performance, facilitating cell adhesion, proliferation, and growth, while facilitating the ingrowth and permeation of bone tissue. Ultimately, the ideal bone fusion results will obtain.@*CONCLUSION@#The microstructure significantly and substantially influences the performance of TPMS bone scaffolds. By deeply exploring the characteristics of these microstructure effects on the performance of bone scaffolds, the design of bone scaffolds can be further optimized to better match specific implantation regions.

Advances in peripatellar osteotomy for treating recurrent patellar dislocation / 中国修复重建外科杂志

OBJECTIVE@#To summarize the progress of research related to the surgical treatment of recurrent patellar dislocation by peripatellar osteotomy in clinical practice, in order to provide reference for clinical treatment.@*METHODS@#The recent literature on peripatellar osteotomy for recurrent patellar dislocation at home and abroad was reviewed, and the bony structural abnormalities, imaging diagnosis, and treatment status were summarized.@*RESULTS@#Abnormalities in the bony anatomy of the lower limb and poor alignment lead to patellofemoral joint instability through the quadriceps pulling force line and play an important role in the pathogenesis of recurrent patellar dislocation. Identifying the source of the deformity and intervening with peripatellar osteotomy to restore the biomechanical structure of the patellofemoral joint can reduce the risk of soft tissue surgical failure, delay joint degeneration, and achieve the target of treatment.@*CONCLUSION@#In the clinical diagnosis and treatment of recurrent patellar dislocation, the factors causing patellofemoral joint instability should be comprehensively evaluated to guide the selection of surgery and personalized treatment.

Research progress on the design of bone scaffolds with different single cell structures / 中国修复重建外科杂志

OBJECTIVE@#To review the research progress of design of bone scaffolds with different single cell structures.@*METHODS@#The related literature on the study of bone scaffolds with different single cell structures at home and abroad in recent years was extensively reviewed, and the research progress was summarized.@*RESULTS@#The single cell structure of bone scaffold can be divided into regular cell structure, irregular cell structure, cell structure designed based on topology optimization theory, and cell structure designed based on triply periodic minimal surface. Different single cell structures have different structural morphology and geometric characteristics, and the selection of single cell structure directly determines the mechanical properties and biological properties of bone scaffold. It is very important to choose a reasonable cell structure for bone scaffold to replace the original bone tissue.@*CONCLUSION@#Bone scaffolds have been widely studied, but there are many kinds of bone scaffolds at present, and the optimization of single cell structure should be considered comprehensively, which is helpful to develop bone scaffolds with excellent performance and provide effective support for bone tissue.

Application of micro-bolus injection and piezoelectric sensors to improve the safety of radiopharmaceuticals bolus injection / 生物医学工程学杂志

Radiopharmaceutical dynamic imaging typically necessitates intravenous injection via the bolus method. However, manual bolus injection carries the risk of handling errors as well as radiological injuries. Hence, there is potential for automated injection devices to replace manual injection methods. In this study, the effect of micro-bolus pulse injection technology was compared and verified by radioactive experiments using a programmable injection pump, and the overall bubble recognition experiment and rat tail vein simulation injection verification were performed using the piezoelectric sensor preloading method. The results showed that at the same injection peak speed, the effective flushing volume of micro-bolus pulse flushing (about 83 μL/pulse) was 49.65% lower than that of uniform injection and 25.77% lower than that of manual flushing. In order to avoid the dilution effect of long pipe on the volume of liquid, the use of piezoelectric sensor for sealing preloading detection could accurately predict the bubbles of more than 100 μL in the syringe. In the simulated injection experiment of rat tail vein, when the needle was placed in different tissues by preloading 100 μL normal saline, the piezoelectric sensor fed back a large difference in pressure attenuation rate within one second, which was 2.78% in muscle, 17.28% in subcutaneous and 54.71% in vein. Micro-bolus pulse injection method and piezoelectric sensor sealing preloading method have application potential in improving the safety of radiopharmaceutical automatic bolus injection.

Experimental study of alendronate sodium in the treatment of denervated skeletal muscle atrophy / 中华骨科杂志

Objective:To observe the effects of alendronate (ALN) on the expression of autophagy signaling pathway related proteins LC3, Beclin-1 and P62 in the muscle tissue of mice with denervated skeletal muscle atrophy, and to explore the potential molecular biological mechanism of ALN in the treatment of skeletal muscle atrophy.Methods:Thirty males C57BL/6 mice were divided into three groups with 10 mices in each group by random number method, including blank control group: sciatic nerve exposed without resection, model group: sciatic nerve exposed and resection, ALN group: sciatic nerve resection +ALN intervention. At the intervention stage, mices were given 1 mg/kg ALN by intragastric administration. The weight of gastrocnemius muscle was weighed by wet weight method. Atpase staining was used to distinguish muscle fiber types. HE staining was used to observe the arrangement and cross-sectional area of gastrocnemius muscle fibers in each group, and further quantitative analysis was performed by Image J 1.48 software. Western blotting and immunohistochemical staining were performed to detect the expressions of MHC and MuRF1 as well as LC3, Beclin-1 and P62 in gastrocnemius tissues of each group.Results:The weight of gastrocnemius muscle in the model group 137±7.80 mg was significantly lower than that in the blank control group 203±10.34 mg, which proved that the denervation muscle atrophy mouse model was successfully established. After intervention, the gastrocnemius muscle weight of ALN group 177±11.65 mg was significantly higher than that of model group, and the muscle mass was significantly improved. HE staining showed that muscle fibers in the model group were loosely arranged and the cross-sectional area was significantly smaller than that in the blank control group, and there were more blue stains among muscle fibers. Atpase staining showed that the distribution of type II muscle fibers in the model group was increased compared with that in the blank control group, and the distribution of type II muscle fibers in the ALN group was decreased compared with that in the model group, but higher than that in the blank control group. The results showed that the most widely distributed muscle fiber cross-sectional area was 600-800μm 2 in the blank control group, 200-400 μm 2 in the model group, and 400-600 μm 2 in the ALN group. The results of quantitative calculation of muscle fiber cross-sectional area by Image J 1.48 showed that the mean value of muscle fiber cross-sectional area in the model group was (352±18) μm 2, which was significantly reduced compared with the blank control group 794±20 μm 2. After ALN treatment, muscle fiber cross-sectional area recovered somewhat. The mean muscle fiber cross-sectional area of ALN group was 578±23 μm 2, which increased muscle fiber cross-sectional area by 29%. Western blotting results showed that the expressions of MHC, LC3 and Beclin-1 in model group were significantly lower than those in blank control group ( P<0.05), while MuRF1 and P62 proteins were significantly higher than those in blank control group ( P<0.05). The MHC, LC3 and Beclin-1 proteins in ALN group were significantly higher than those in model group (0.12±0.01 vs. 0.10±0.003, 0.15±0.02 vs. 0.10±0.02, 0.13±0.03 vs. 0.09±0.04). MuRF1 and P62 proteins in ALN group were significantly lower than those in model group (0.10±0.004 vs. 0.15±0.01, 0.16±0.03 vs. 0.20±0.03). MHC immunohistochemical staining showed that the expression of MHC in gastrocnemius of mice in model group was significantly lower than that in blank control group, and the expression of MHC in gastrocnemius of mice in ALN group was higher than that in model group ( P<0.05). Conclusion:ALN has a therapeutic effect on skeletal muscle atrophy, and its mechanism may be realized by moderately activating the LC3/Beclin-1 autophagy signaling pathway.

Anterior cage inserting for old thoracolumbar fractures with kyphosis through facet joint approach / 中华骨科杂志

Objective:To investigate the clinical effects of anterior cage inserting for old thoracolumbar fractures with kyphosis through facet joint approach.Methods:A retrospective analysis was conducted on 32 patients with old thoracolumbar fractures complicated with kyphosis admitted from January 2018 to December 2019, including 14 males and 18 females. The average age was 47.3±13.1 years (range, 26-70 years). Thoracolumbar injury classification (TLICS) scores of patients with initial injury were 3-5 points, with an average of 4.0 points. After 6.3±2.9 months (range, 3-16 months) conservative treatment, intractable thorax and lumbar or back pain still existed. Anterior cage inserting via articular protrusion was performed in 15 cases and posterior screw placement and bone grafting fusion of injured vertebrae was performed in 17 cases. Preoperative sagittal Cobb angle was 27.0°±3.9° and 26.8°±4.6° in the anterior cage inserting group and fixation on fractured vertebrae group ( t=0.07, P=0.946), respectively. Sagittal vertical axis (SVA) was 4.2±1.8 cm and 4.1±2.1 cm ( t=0.14, P=0.887), respectively. The number of patients with ASIA impairment scale (AIS) of the anterior cage inserting group before surgery was 1 in grade C, 4 in grade D and 10 in grade E. However, the number of that in fixation on fractured vertebrae group was 2 in grade C, 2 in grade D and 13 in grade E. There was no significant difference between the two groups (χ 2=1.34, P=0.520). Results:All 32 patients were followed up for 12.2±3.1 months in the anterior cage inserting group and 12.0±3.3 months in fixation on fractured vertebrae group. The operative duration of the anterior cage inserting group and fixation on fractured vertebrae was 128±24.5 min and 123±40.6 min ( t=0.42, P=0.681). The intraoperative blood loss was 485±12.6 ml and 478±16.3 ml ( t=0.13, P=0.894), respectively. At the last follow-up, the improvement rate of VAS score of the anterior cage inserting group was higher than that of fixation on fractured vertebrae group (90%±10% vs. 75%±20%, t=3.17, P=0.004). The height of anterior margin of injured vertebra in the two groups was increased by 1.02±0.10 cm and 0.29±0.14 cm, the change rate of anterior cage inserting group was higher than that of fixation on fractured vertebrae group (67.1%±31.5% vs. 19.0%±14.9%, t=16.29, P<0.001). The sagittal Cobb angle of the anterior cage inserting group was significantly lower than that of fixation on fractured vertebrae group (7.4°±1.5° vs. 11.6°±2.5°, t=-5.85, P<0.001). The SVA of anterior cage inserting group was lower than that of fixation on fractured vertebrae group (1.1±0.6 cm vs. 1.6±0.6 cm, t=2.35, P=0.025). There were 15 patients in AIS grade E in the anterior cage inserting group, while 1 patient in grade D and 16 patients in grade E in fixation on fractured vertebrae group without significant difference between the two groups (χ 2=0.83, P=0.706). Conclusion:The treatment of old thoracolumbar fractures with kyphosis through facet joint approach and anterior fixation could achieve satisfied effects and could relieve pain symptoms of thoracolumbar and back, compared with posterior fusion for injured vertebra with nail and bone grafting.

Research progress in the role of TRPV channel-induced Ca 2+ signal in osteoclast differentiation and bone resorption / 中华骨科杂志

Osteoclast is a type of multinuclear giant cell, which plays a role in bone resorption in the homeostasis of bone mass. Excessive bone resorption leads to osteoporosis and other diseases characterized by decreased bone mass. Ca 2+ metabolism plays an important role as a second messenger in the differentiation, migration, fusion and bone resorption of osteoclast. The transient receptor potential vanilloid (TRPV) ion channel is expressed in a variety of cells, including osteoclast. Current studies have found that the TRPV ion channel can participate in the production and bone resorption function of osteoclast by increasing intracellular Ca 2+ concentration and calcium oscillations. This article reviews the relationship between the TRPV ion channel and the changes of Ca 2+ concentration and the potential mechanisms involved in osteoclast activity, so as to provide a reference for further research on diseases characterized by abnormally increased activation of osteoclast in the future.

Morphology and distribution characteristics of subchondral bone cysts in the talus based on CT three-dimensional reconstruction / 中华创伤杂志

Objective:To analyze the morphology and distribution characteristics of subchondral bone cysts of the talus by CT three-dimensional reconstruction.Methods:A total of 176 patients diagnosed with subchondral bone cyst of the talus after CT scan of the ankle or foot from 2015 to 2020 were retrieved from the imaging report database of Tianjin Hospital, including 77 males and 99 females, aged 14-84 years［(56.1±14.0)years］. After three-dimensional reconstruction of the talus and cyst area by Mimics 20.0 software, an equal 2×2 grid configuration was constructed to divide the domed articular surface into four regions: anteromedial, anterolateral, posteromedial and posterolateral. For subchondral cyst of the talus, area involved under grid localization, gender, age and side of the onset were recorded. The anteroposterior diameter, transverse diameter, depth, surface area and volume of the subchondral bone cyst of the talus were measured.Results:Subchondral cyst of the talus was anteromedial in 131 patients (74.4%), anterolateral in 5(2.8%), posteromedial in 34(19.3%), and posterolateral in 6(3.4%). Subchondral cyst of the talus occurred in the older aged (≥60 years) for 78 patients (44.3%), in the middle aged (45-59 years) for 62(35.2%), in young adults for 32(18.2%), and in preadolescents for 4(2.3%). The age composition of the subchondral cyst of the talus involving the anteromedial, anterolateral, posteromedial and posterolateral regions was 59(49, 64)years, 44(39, 45)years, 61(54, 68)years and 40(22, 58) years, respectively (all P<0.01). There were no statistically significant differences in gender and side of the onset (all P>0.05). The anteroposterior diameter of the subchondral bone cysts located anteromedially, anterolaterally, posteromedially and posterolaterally was (9.7±4.4)mm, (3.5±1.1)mm, (10.3±4.4)mm and (2.1±0.8)mm, respectively; the transverse diameter was (5.4±1.7)mm, (3.9±1.8)mm, (5.9±2.2)mm and (3.4±1.1)mm, respectively; the depth was (7.1±2.4)mm, (3.2±2.2)mm, (8.2±3.0)mm and (3.9±1.9)mm, respectively; the surface area was 156.1(82.6, 198.2)mm 2, 23.0(21.4, 28.9)mm 2, 180.0(75.1, 230.4)mm 2 and 28.0(20.3, 36.7)mm 2, respectively; the volume was 77.1(37.1, 129.1)mm 3, 23.9(14.2, 37.8)mm 3, 104.6(37.7, 157.4)mm 3 and 13.0(10.4, 16.0)mm 3, respectively. When comparing the anteroposterior diameter, transverse diameter, depth, surface area and volume of the subchondral bone cysts in the anteromedial and posteromedial regions with the anterolateral and posterolateral regions, the differences were statistically significant (all P<0.01) except for the transverse diameter of the subchondral bone cysts in the anteromedial region and the anterolateral region ( P>0.05). In addition, the depth of subchondral bone cysts in the anteromedial region was significantly greater than that in the posteromedial region ( P<0.05). Conclusions:Subchondral bone cysts of the talar are commonly found in the middle- and old-aged population. Anteromedial lesions of the talar dome are the most commonly seen, with large and deeply involved cysts, followed by posteromedial lesions of the dome, while anterolateral and posterolateral lesions of the dome are less common and have smaller cyst sizes. An equal 2×2 grid configuration for talar cysts is useful in positioning and characterizing bone cysts, and can assist clinicians in accurately diagnosing and treating bone cysts.

Research progress in animal models of sarcopenia / 中华老年医学杂志

Sarcopenia, referred to as myopenia, is a systemic syndrome characterized by decreased muscle mass and muscle strength, and decline of motor function.The elderly are a high incidence group of myopenia.With the aging of the world's population becoming increasingly severe, the incidence rate of sarcopenia has also increased, which has brought a heavy burden to the elderly family and society, and has become an important social health problem for the elderly.At present, there are more and more researches on sarcopenia, but the pathogenic factors of sarcopenia are complex and diverse.The prevention and treatment of sarcopenia still need to be further explored and studied.The establishment of an ideal animal model is the key premise and basis for the related research of sarcopenia.In this paper, the different modeling methods, advantages and disadvantages as well as the scope of application of sarcopenia animal models are described, which can provide reference and help for the subsequent animal experimental research of sarcopenia.

Application of 3D printed patient-specific surgical guide plate in orthopedic surgery / 中华创伤骨科杂志

A 3D printed patient-specific surgical guide plate is an auxiliary device made with the help of computer-aided design and 3D printing technology according to a surgical plan. It is used in reduction and internal fixation of fracture and specific corrective osteotomy as well. It is very adaptive as it has been widely used in trauma surgery, joint surgery and spine surgery, as well as in surgical treatment of bone tumors. Digital orthopedic technology is an important means to realize orthopedic precision medicine. This paper reviews the technical advantages, applications, main problems and future prospects of 3D printed patient-specific surgical guide plates in the field of orthopedics based on the recent literature.

Analysis on Mechanical Characteristics of Femoral Neck Fracture with Different Reduction Qualities / 医用生物力学

Objective To investigate biomechanical characteristics of femoral neck fracture with different reduction qualities. Methods Three cases of Sawbones artificial femoral models were selected, and two cases of Pauwel III femoral neck fracture were modeled. Three cannulated screws were inserted into the models in the form of inverted triangle to fix the fracture. Two cases maintained different reduction qualities (defined as Model 1 and Model 2). In the 3 third case, no modeling operation was performed (defined as intact model). Then the strain gauges were respectively pasted on regions of interest of the 3 femoral models. Finally, the femur model was applied with the vertical load on mechanical testing machine. Results When the displacement of femoral head reached 4 mm, the average load of intact model, Model 1 and Model 2 was (236.30±5.35), (196.57±3.56), (69.50±2.95) N, showing significant differences. When the displacement of femoral head reached 5 mm, the average load of intact model, Model 1 and Model 2 was (276.7±3.40)，(232.93±2.64)，(80.83±4.54) N, showing significant differences. Conclusions The lower the reduction quality of the femoral neck fracture, the weaker the ability of the femur to bear stress, the higher the probability of nonunion, re-fracture and femoral head necrosis in the process of postoperative rehabilitation.

Clinical characteristics analysis of adult femoral neck fracture: a retrospective hospital-based study / 中华骨科杂志

Objective:To analyze the clinical characteristics of patients with femoral neck fracture in Tianjin Hospital.Methods:Data of femoral neck fracture patients discharged from Tianjin Hospital from January 1, 2016 to December 31, 2017 were retrospectively analyzed. The gender, age, fracture type, injury mechanism and treatment method were collected.Results:Total of 2,150 eligible patients including 736 males and 1414 females were selected. There were significant differences in the gender distribution in different age groups ( χ2=91.63, P<0.001). Among young patients, males were more than females, while among middle-aged and elderly patients, females were more than males. The main type of fracture was displaced type (75.56%, 1,646/2,150), the displaced rate was the lowest in young patients (55.17%, 64/116), while it was the highest in old patients (81.91%, 1,159/1,415). The main injury mechanism of the three age groups were falls [young 61.21% (71/116), middle 80.29% (497/619), eldly 91.24% (1,291/1,415)]. There was a significant difference in the treatment methods between different age groups ( χ2=1,057.11, P<0.001). The main treatment method for young and middle-aged patients was internal fixation, no matter whether the fracture was displaced or not. The proportion of undisplaced patients with internal fixation (86.22%, 169/196) was higher than that of displaced patients with internal fixation (62.88%, 266/423) in middle-aged group ( χ2=34.93, P<0.001). In the elderly, more patients used internal fixation in undisplaced group, while more patients used hemiarthroplasty in displaced group. The age of old femoral neck fracture (median age was 74) was older than that of fresh fracture (median age was 70) ( Z=-2.777, P=0.005). And the displaced rate of patients with old femoral neck fracture (92.41%, 73/79) was higher than that of the fresh ones (75.95%, 1,573/2,071)( χ2=11.48, P=0.001). The patients with old femoral neck fracture usually adopt total hip replacement, while the proportion of three kinds of operation (internal fixation, hemiarthroplasty, total hip replacement) were similar among the fresh ones, and the internal fixation was the most. Conclusion:Femoral neck fracture is the most common in elderly women. The patients with displaced fracture are more than that with undisplaced fracture. Falling is the main injury mechanism in both young and old people. Internal fixation is commonly used in young and middle-aged patients, while arthroplasty is often used in elderly patients.

Treatment of skin and soft tissue defect with Nice combination with elastic dressing and stretch / 中华骨科杂志

Objective@#To explore the clinical effects of Nice knot combined with elastic compress and stretch in treating skin and soft tissue defect.@*Methods@#From August 2017 to April 2019, a total of 23 patients, 10 males and 13 females, aged 36.5±5.3 years (range 26-76 years), were retrospectively analyzed. The defect size was 60±5.3 cm2 (28-96 cm2). Under local anesthesia, the wound was debrided thoroughly, sutured and fixed by Nice knot. The wound was fixed by elastic dressing and traction. The wound was retracted every 3 days during dressing change. The wound healing grade, healing rate, healing time, and postoperative Vancouver Scar Scale (VSS) were observed and recorded.@*Results@#All operations were performed successfully in the debridement room. The operation time was 42±10.5 min (range 30-50 min), intraoperative bleeding 30±2.5 ml (range 20-60 ml), and the operation cost 180±11.5 RMB (range 160-240 RMB). Twenty patients were followed up for 4±2.5 months (range 3-6 months). The wound healing rate of 23 patients was 50%±3.5% (range 40%-56%). For the 20 patients, the wound healing rate was 65%±4.3% (range 53%-75%), 74%±4.5% (range 65%-80%), 83%±1.8% (range 76%-85%), 90%±1.6% (range 84%-95%) and 95%±3.5% (range 94%-98%) at 3, 6, 9, 12 and 15 days, respectively. The wound healing rate of 20 patients was 100% at the 42nd days of follow-up. Wound healing rate of Grade A and grade B was 95% (19/20) with scar VSS score 4(3, 6). The excellent and good rate of grade B was 80% (16/20). Two cases were sutured and fixed with Nice knot after 10 days because of the partial loss of the sutures. One case was treated with vacuum sealing drainage (VSD) on-line junction because infection was not completely controlled. Local infection was controlled and the wound was contracted by Nice junction at 1 week.@*Conclusion@#The treatment of skin and soft tis sue defect with Nice combination with elastic dressing and traction has the advantages of simple operation, low operation condition, short operation time, less bleeding, low cost, high wound healing grade and healing rate, suitable for basic level hospital application and promotion.

Treatment of skin and soft tissue defect with Nice combination with elastic dressing and stretch / 中华骨科杂志

Objective To explore the clinical effects of Nice knot combined with elastic compress and stretch in treating skin and soft tissue defect.Methods From August 2017 to April 2019,a total of 23 patients,10 males and 13 females,aged 36.5±5.3 years (range 26-76 years),were retrospectively analyzed.The defect size was 60±5.3 cm2 (28-96 cm2).Under local anesthesia,the wound was debrided thoroughly,sutured and fixed by Nice knot.The wound was fixed by elastic dressing and traction.The wound was retracted every 3 days during dressing change.The wound healing grade,healing rate,healing time,and postoperative Vancouver Scar Scale (VSS) were observed and recorded.Results All operations were performed successfully in the debridement room.The operation time was 42±10.5 min (range 30-50 min),intraoperative bleeding 30±2.5 ml (range 20-60 ml),and the operation cost 180±11.5 RMB (range 160-240 RMB).Twenty patients were followed up for 4±2.5 months (range 3-6 months).The wound healing rate of 23 patients was 50％±3.5％ (range 40％-56％).For the 20 patients,the wound healing rate was 65％±4.3％ (range 53％-75％),74％±4.5％ (range 65％-80％),83％±1.8％ (range 76％-85％),90％±1.6％ (range 84％-95％) and 95％±3.5％ (range 94％-98％) at 3,6,9,12 and 15 days,respectively.The wound healing rate of 20 patients was 100％ at the 42nd days of follow-up.Wound healing rate of Grade A and grade B was 95％ (19/20) with scar VSS score 4(3,6).The excellent and good rate of grade B was 80％ (16/20).Two cases were sutured and fixed with Nice knot after 10 days because of the partial loss of the sutures.One case was treated with vacuum sealing drainage (VSD) on-line junction because infection was not completely controlled.Local infection was controlled and the wound was contracted by Nice junction at 1 week.Conclusion The treatment of skin and soft tissue defect with Nice combination with elastic dressing and traction has the advantages of simple operation,low operation condition,short operation time,less bleeding,low cost,high wound healing grade and healing rate,suitable for basic level hospital application and promotion.