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Computational models and inverse dynamic optimization methods are used to predict in-vivo spinal loading. Spinal force is conventionally predicted using the constant loading path method, which is based on the concept that the physiological directions of the spine loads follow the same path of the spinal curve. However, the global convergence optimization method, in which the instantaneous center of rotation of the joint should be also predicted, is necessary for accurate prediction of joint forces of the human body. In this study, we investigate the joint forces, instantaneous centers of rotation, and muscle forces of the human lumbar spine using both global convergence optimization method and constant loading path method during flexion, upright standing, and extension postures. The joint forces predicted using the constant loading path method were 130%, 234%, and 253% greater than those predicted using the global convergence optimization method for the three postures. The instantaneous centers of rotation predicted using the global convergence optimization method were segment level-dependent and moved anteriorly in the flexion and posteriorly in the extension, whereas those predicted using the constant loading path method moved posteriorly in both the flexion and extension. The data indicated that compared to the global convergence optimization method, the constant loading path method introduces additional constraints to the spinal joint model, and thus, it results in greater joint and muscle forces.

October 2021,《自然》杂志于2021年10月刊登“电针驱动迷走-肾上腺轴的神经解剖学机制”一文，引起了针灸学术界的广泛关注和讨论。在前期工作的基础上，该研究证实PROKR2-Cre神经纤维在躯体不同部位和层次的差异性分布是电针低强度刺激“足三里”或“手三里”穴，通过“迷走-肾上腺轴”产生抗炎效应的关键。该研究成果是针灸基础科研领域的里程碑事件，是针灸学科与神经-免疫学科交叉相互碰撞融合的代表作，揭示了针刺起效的部分因素构成和穴位结构相对特异性的神经解剖学基础，对未来针灸科研模式的变革和针灸科研成果的转化具有一定指导意义，其研究思路、方法和结论值得针灸科研工作者学习和借鉴。.

The purpose of this study is to evaluate the difference of patellofemoral kinematics between weightbearing and non-weightbearing conditions in the arthrofibrotic knee after anterior cruciate ligament (ACL) reconstruction.Twenty patients with arthrofibrosis after ACL reconstruction were included in the study. Computed tomography scanner and dual fluoroscopic imaging techniques were used to compare patellofemoral kinematics of the affected knee between weightbearing knee flexion and non-weightbearing knee flexion. In both positions, patellofemoral kinematics in six degrees-of-freedom (6 DOF) were measured respectively.The patellar lateral tilt angle (p = 0.007) and medial patellar translation (p = 0.043) under the weightbearing condition were significantly decreased compared to the non-weightbearing task between 5° and 15° of knee flexion. The lateral patellar translation during a non-weightbearing task was significantly decreased between 60° and 75° of knee flexion (p = 0.005), and the inferior patellar translation under the weightbearing condition was significantly increased between 45° and 75° of knee flexion (p = 0.040).These results indicate that patellofemoral kinematics during non-weightbearing positions do not sufficiently represent the patellar tracking during functional weightbearing activities. Our findings of this study establish the clinical relevance and significance of assessing the patellofemoral kinematics under the weightbearing condition when evaluating patients with arthrofibrosis after ACL reconstruction.Trial registration number: ChiCTR1900025977.

Professor成都中医药大学梁繁荣教授团队于2019年7月29日在

Context: Performance in strength and assessment of patellar tracking is important for patients with arthrofibrosis after anterior cruciate ligament (ACL) reconstruction. Objective: The study was to examine the difference of patellofemoral kinematics between the affected and the contralateral limb and to evaluate the relationship between knee extensor strength and patellofemoral kinematics in patients with arthrofibrosis after ACL reconstruction. Design: Cohort study (diagnosis); level of evidence, 3. Setting: Laboratory. Patients: A prospective cohort of 20 patients with arthrofibrosis after ACL reconstruction was recruited. Interventions: A total of 20 patients who underwent arthroscopic reconstruction of the double-bundle ACL with a hamstring tendon autograft received standardized patellofemoral kinematics testing and knee extensor strength testing within 6 months after primary ACL reconstruction. Computed tomography and dual fluoroscopic imaging were used to evaluate in vivo patellofemoral kinematics of affected and contralateral knees during a lunge task. Knee extensor mechanism strength was measured using a handheld dynamometer. Main Outcome Measures: A limb symmetry index of knee strength and patellar mobility was calculated and satisfactory performance defined as ≥90%. Results: There was a statistically significant decrease in the range of patellar inferior shift (P = .020; d = 0.81), flexion (P = .026; d = 0.95), lateral tilt (P = .001; d = 1.04), and lateral rotation (P d = 0.89) in the affected knee compared with the contralateral knee from 15° to 75° of knee flexion. There was a strong positive linear correlation between knee extensor strength and patellar inferior shift (r = .747; P = .008). A knee extensor strength limb symmetry index Conclusions: Patients with arthrofibrosis after ACL reconstruction presented decreased patellar mobility in the arthrofibrotic knee compared with the contralateral knee. The strong correlation between knee extensor strength and patellar inferior shift of the arthrofibrotic knee demonstrates the importance of knee extensor strength in the diagnosis and treatment of patients with knee arthrofibrosis. The knee extensor mechanism strength has high sensitivity but low specificity in identifying a decrease in patellar inferior shift in patients with arthrofibrosis after ACL reconstruction.

Ankle joint kinematics is mainly stabilized by the morphology of the talar dome and the articular surface of tibiofibular mortise as well as the medial and lateral ligament complexes. Because of this the bicondylar geometry of talus dome is believed to be crucial for ankle implant design. However, little data exist describing the precise anatomy of the talar dome and the talocrural joint axis. The aim of this study is to document the anatomy of the talar dome and the axis of the talocrural joint using three-dimensional (3D) computed tomographic (CT) modeling. Seventy-one participants enrolled for CT scanning and 3D talar model reconstruction. All the ankles were held in a neutral position during the CT scanning. Six points on the lateral and medial crest of the talar dome were defined. The coordinate of the six points; radii of lateral-anterior (R-LA), lateral-posterior (R-LP), medial-anterior (R-MA), and medial-posterior (R-MP) sections; and inclination angle of the talar dome were measured, and the inclination and deviation angles of the talocrural joint axis were determined. The mean values of R-LA, R-LP, R-MA, and R-MP were 19.23 ± 2.47 mm, 18.76 ± 2.90 mm, 17.02 ± 3.49 mm, and 22.75 ± 3.04 mm. The mean inclination angle of the talar dome was 9.86 ± 3.30 degrees. Gender variation was found in this parameter. The mean inclination and deviation angles were 8.60 ± 0.07 and 0.76 ± 0.69 degrees for the dorsiflexion axis and −7.34 ± 0.07 and 0.09 ± 0.18 degrees for the plantarflexion axis. Bilateral asymmetries between the medial and lateral crest of the talar dome were found, which resulted in different dorsiflexion and plantarflexion axes of the talocrural joint. Currently, no ankle implants replicate this talar anatomy, and these findings should be considered in future implant designs.

OBJECTIVE: To investigate the six degrees of freedom (6DOF) kinematics of anterior cruciate ligament (ACL) deficient knees during gait and to explore the clinical significance of a novel knee joint stability assessment system (Opti_Knee, Innomotion, Shanghai, China) in comparison with imaging and arthroscopic examination. METHODS: Three subjects diagnosed with ACL deficient knees on the basis of preoperative MRI and CT findings were subjected to treadmill gait analysis. Motion of both knees in 6DOF was measured and analyzed with an optical joint kinematics measurement system. Arthroscopic examination, the gold standard, was performed to confirm the final diagnosis and the clinical diagnosis of ACL deficiency by imaging and motion marker techniques compared with this gold standard. RESULTS: Only two of the three subjects diagnosed with ACL deficiency by imaging techniques were later confirmed to have this condition by arthroscopic examination; the third was found to have an intact ACL. When the kinematics of their injured and contralateral knees were compared, abnormalities were found in the two subjects confirmed by arthroscopy to be ACL deficient However, no kinematic difference between the two knees was found in the ACL intact subject. CONCLUSIONS: Opti_Knee (Innomotion) can detect abnormal kinematics in ACL deficient knees and thus provides an effective way of assisting the diagnosis of this condition and has potential for clinical application.

For a large aperture astronomical telescope, it is difficult to get the best performance design because there are so many design parameters need to be optimized. In the past, the optimization was carried out for each design parameter individually and the cross impact of different design parameters was neglected. To solve this problem, integrated optimum design was adopted to identify the interaction between parameters and to obtain an approximate explicit function by fitting those calculated design points, so the best design point can be determined. In this paper, an integrated optimum model was established to quest the optimized design of a honeycomb mirror. The individual and interactive impact of design parameters to the mirror’s surface error were analyzed based on this model. Through the optimized integrated design, the weight of mirror had been declined from 109.1 Kg to 74.1 Kg with a little increase of the mirror surface error.

To propose views and concepts on the degradation of cultivated Gastrodia populations.The differences between natural and cultivated Gastrodia populations were compared and discussed in terms of their biological features, qualities and yields.There were changes and degradation in biological features and some important properties of yield in cultivated Gastrodia.The direct reason of cultivated Gastrodia degradation is the ecological disturbace of forests and the decreasing amount of natural Gastrodia populations; The indirect reason is manual pollination and other changes of the natural growing environment.