[Retrospective analysis and comparison of total internal disability preservation technique and standardized reconstruction technique].

OBJECTIVE: To investigate the efficacy and clinical results of total internal protection technique in anterior cruciate ligament reconstruction. METHODS: A total of 56 patients undergoing anterior cruciate ligament reconstruction treated from January 2018 to December 2019 were selected. According to the different surgical methods, they were divided into total internal reconstruction group and standard bone tunnel group. There were 21 patients in the total internal reconstruction group, including 15 males and 6 females, aged from 20 to 48 with an average of (35.6±6.7) years old, and 35 patients in the standard tibial tunnel group, including 26 males and 9 females, aged 22 to 51 years old with an average of (33.7±9.6) years old. Preoperative examination of Lachman test was positive, magnetic resonance indicated anterior cruciate ligament rupture. There were no significant differences between the two groups in age, sex, body mass index, time from injury to ACL reconstruction, combined meniscus injury and operation method, operation time, ligament diameter, ligament length and other general information. Postoperative evaluation included operation duration, length and diameter of transplanted tendon after braid. International Knee Documentation Committee (IKDC) score, Lysholm score, Tegner score and perioperative complications 2 years after surgery. RESULTS: Both groups were followed up, ranging from 24 to 30 months with an average of (26.9±3.4) months. Postoperative incision healing was good, and no failure or joint infection occurred at the last follow-up. There was no statistically significant difference between the two groups in IKDC score, Lysholm score and Tegner score before, 1 year and 2 years after surgery. However, IKDC score, Lysholm score and Tegner score at 1 year and 2 years after surgery. CONCLUSION: The same postoperative function and stability of knee joint can be obtained by both the residual whole technique and the standardized reconstruction technique. In the residual whole group, only the semitendinosus muscle is taken, and the femoral thin muscle is retained, with greater tibial bone mass preserved, which is safe and effective in clinical practice.

Biomechanical improvement of anterior talofibular ligament by augmentation repair of ligament advance reinforcement system: a cadaver study.

BACKGROUND: Ankle sprain are one of the most frequent sports injuries. Some individuals will develop chronic lateral ankle instability (CLAI) after ankle sprain and suffer from recurrent ankle sprain. Current surgical treatment of CAI with anterior talofibular ligament (ATFL) rupture fails to restore the stability of the native ATFL. Ligament Advance Reinforcement System (LARS) augmentation repair of ATFL was developed to improve its primary stability after repaired. METHODS: This study was performed to evaluate whether LARS augmentation repair of ATFL had similar stability as the modified Broström repair and the intact ATFL to maintain ankle construct stability. Standardized surgical techniques were performed on eighteen fresh frozen cadaver ankle specimens. The intact ATFL group has just undergone an ATFL exploratory surgery. The modified Broström procedure is based on anatomical repair of the ATFL with a 2.9 mm suture anchor, and the LARS procedure is an augmentation procedure of the ATFL using LARS ligaments based on the modified Broström procedure. A dynamic tensile test machine was used to assess load-to-failure testing in the three groups. The ultimate failure load and stiffness were calculated and reported from the load-displacement curve. A one-way analysis of variance was used to detect significant differences (p < 0.05) between the LARS augmentation repair, the modified Broström repair and the intact ATFL, followed by least significant difference (LSD) post-hoc tests. RESULTS: The LARS augmentation repair group showed an increased in ultimate failure to load and stiffness compared to the other two groups. There were no significant differences in ultimate failure to load and stiffness between the modified Broström and the intact ATFL, the LARS ligament for ATFL augmentation allows for improved primary stability after repair and reduced stress on the repaired ATFL, which facilitates healing of the remnant ligament. CONCLUSIONS: The LARS augmentation repair of ATFL represents a stable technique that may allow for the ankle stability to be restored in patients with CAI after surgery.

Timosaponin B-II alleviates osteoarthritis-related inflammation and extracellular matrix degradation through inhibition of mitogen-activated protein kinases and nuclear factor-κB pathways in vitro.

Osteoarthritis (OA), an inflammatory response in chondrocytes, leads to extracellular matrix (ECM) degradation and cartilage destruction. Timosaponin B-II (TB-II) is the main bioactive component of Rhizoma Anemarrhenae with reported antioxidant and anti-inflammatory effects. This study investigated the anti-OA function and mechanism of TB-II on IL-1ß-stimulated SW1353 cells and primary rat chondrocytes. We firstly screened the concentration of TB-II in SW1353 cells and primary rat chondrocytes using CCK-8 assay. Thereafter, SW1353 cells and chondrocytes were, respectively, pretreated with TB-II (20 and 40 µg/mL) and TB-II (10 and 30 µg/mL) for 24 h and then stimulated with interleukin 1ß (IL-1ß, 10 ng/mL) for another 24 hours. Results showed that TB-II suppressed the production of reactive oxygen species, the protein levels of inducible nitric oxide synthase and cyclooxygenase-2 in IL-1ß-stimulated SW1353 cells and chondrocytes. IL-1ß-induced high secretion levels of nitric oxide and prostaglandin 2, TNF-α, IL-6 and MCP-1 were down-regulated by TB-II treatment, indicating an anti-inflammatory effect of TB-II on OA in vitro condition. Moreover, TB-II weakened the mRNA and protein expression of (matrix metalloproteinase) MMPs including MMP-1, MMP-3, and MMP-13, indicating the protection of TB-II against ECM degradation. Mechanically, TB-II suppressed MAPKs and NF-κB pathways under IL-1ß stimulation evidenced by the down-regulated protein expression of p-ERK, p-p38, p-JNK, p-p65 and the reduced translocation of p65 subunit to the nucleus. The present study demonstrated that TB-II might become a novel therapeutic agent for OA treatment through repressing IL-1ß-stimulated inflammation, oxidative stress and ECM degradation via suppressing the MAPKs and NF-κB pathways.

Model-Aided Localization and Navigation for Underwater Gliders Using Single-Beacon Travel-Time Differences.

An accurate motion model and reliable measurements are required for autonomous underwater vehicle localization and navigation in underwater environments. However, without a propeller, underwater gliders have limited maneuverability and carrying capacity, which brings difficulties for modeling and measuring. In this paper, an extended Kalman filter (EKF)-based method, combining a modified kinematic model of underwater gliders with the travel-time differences between signals received from a single beacon, is proposed for estimating the glider positions in a predict-update cycle. First, to accurately establish a motion model for underwater gliders moving in the ocean, we introduce two modification parameters, the attack and drift angles, into a kinematic model of underwater gliders, along with depth-averaged current velocities. The attack and drift angles are calculated based on the coefficients of hydrodynamic forces and the sensor-measured angle variation over time. Then, instead of satisfying synchronization requirements, the travel-time differences between signals received from a single beacon, multiplied by the sound speed, are taken as the measurements. To further reduce the EKF estimation error, the Rauch-Tung-Striebel (RTS) smoothing method is merged into the EKF system. The proposed method is tested in a virtual spatiotemporal environment from an ocean model. The experimental results show that the performance of the RTS-EKF estimate is improved when compared with the motion model estimate, especially by 46% at the inflection point, at least in the particular study developed in this article.