The 2022 Beijing Winter Olympic Games comes to the final stage of preparation. This paper reviews the incidence and distribution characteristics of sports injuries from studies of Winter Olympic Games. In view of their high incidence of injuries and high level of attention in China, the skiing, the speed skating, the figure skating, and the ice hockey are discussed in detail with regard to the history of development and the event characteristics, the incidence and the mechanism of injuries. Special focus is given to the winter sports induced head injuries, which received insufficient attention in the past.

The movement pattern and the corresponding biomechanical mechanisms of patients after the anterior cruciate ligament (ACL) reconstruction are essential factors for improving the postoperative effects and preventing secondary injuries. The three-dimensional kinematic, kinetic data, and the surface electromyography activity data are collected bilaterally (for surgical, intact limbs) during patients' level walking 6 to 12 months after the ACL reconstruction (7.4±1.3 months). The three-dimensional angles and moments of the knee joint are calculated. The activation levels of the bilateral rectus femoris, the vastus medialis, the vastus lateralis, the biceps femoris, and the semitendinosus are also evaluated. It is shown that for the surgical limb, the peak knee flexion angle and the knee flexion-extension range of motion are significantly smaller, during the loading response, while the peak external rotation angle is significantly larger, compared with the intact limb. The surgical limb has smaller peak knee extension moment during the loading response phase, smaller peak knee flexion moment, and external rotation moment during the terminal stance phase compared with the intact limb. The peak activation level of the rectus femoris during the loading response phase, and the peak activation levels of the biceps femoris and the semitendinosus during the pre-swing phase are significantly higher in the surgical limb as compared with the intact limb. Patients have a stiffer gait pattern with a significant smaller peak knee flexion angle during the early stance and swing phases in the surgical limb 6 to 12 months after the ACL reconstruction. Patients also have a higher activation level of the quadriceps and the hamstring in the surgical limb compared with the intact limb. The surgical limb also has a greater knee external rotation during the loading response phase and a smaller external rotation moment during the terminal stance phase compared with the intact limb. The rehabilitation protocol after the ACL reconstruction should focus on the abnormal changes in the muscle function and the gait characteristics for better postoperative outcomes.

To analyze the correlation of the preoperative serum biomarkers and the body mass index with the preoperative knee scoring and the pre/post-operative pain scores for patients with ACL rupture, the preoperative data of the serum bio-markers and the body mass index are collected from 52 patients, to make the correlation analysis for the preoperative knee scoring and the pre/post-operative pain scores by Shapiro-Wilk and Spearman tests. Positive correlations are found between the preoperative blood uric acid level and the pre/post-operative pain scores, between the body mass index and the preoperative Lysholm score and the postoperative pain score, and between the creatine kinase level and the postoperative pain score.

The anterior cruciate ligament (ACL) is an important structure of the knee, easily getting hurt. Currently, it is a common practice using the autologous tendon graft to reconstruct the ACL and to treat the ACL injury. However, the tendonbone interface heals slowly after the ACL reconstruction, which affects the early rehabilitation of the patients. The Panax Notoginseng Saponins (PNS), a blood-activating and blood-stasis drug, is often used for the treatment of fractures. Our previous experiments show that the PNS can significantly enhance the osteogenesis effect of the tendon autograft in the reconstruction of the ACL. Thus, this paper focuses on the effect of the PNS on the osteogenic differentiation of the tendon derived stem cells (TDSCs). The TDSCs of passage 3 are divided into two groups, the PNS group and the negative control group. The effect of the PNS on the cell activity is detected by the flow cytometry and the CCK8. After 72 hours of the PNS treatment, the TDSCs are cultured with the osteogenic medium, and the expression of the osteogenic marker ALP is detected by the ALP staining and the Elisa. The TDSCs are subcutaneously injected into nude mice after the PNS treatment, and then the micro-CT is used to detect the ectopic osteogenesis 4 weeks later. Compared with the negative control group, it is shown that the PNS could promote the osteogenic differentiation of the TDSCs and the ectopic osteogenesis in nude mice.

It is important to have a sufficient femoral tunnel length for the graft fix strength and the maturation in the anterior cruciate ligament reconstruction. The high resolution MRI is used on the knees of 6 young healthy volunteers. Based on the reconstructed MRI 3D models. two main observations are made:for the I.D.E.A.L. point as the fixed femoral tunnel location, the higher the tunnel outlet point, or the larger the femoral runnel angle, the longer tunnel would be achieved; and the outlet curves with the tunnel length of 30mm, 35mm, 40mm arranged from lower to upper in an ascending order on the lateral cortex of the lateral femoral condyle, with the mean maximum femoral runnel angle of 17.2°±8.6°, 31.6°±9.1° and 41.4°±8.8°. Therefore, beside the anatomy characteristics such as the sizes of the femur and the intercondylar notch, the length of the femoral tunnel in the trans-portal reconstruction is related with the anterior-medial portal position. For a fixed tunnel location, to get a longer tunnel length, the relative position of the skin portal to the tunnel location should be even lower, and using the accessory for the anterior-medial portal or increasing knee flexing angle, a longer femoral tunnel would be obtained.

Ski is an exciting and competitive sport. In view of the final preparation stage of Beijing 2022 Winter Olympics, this paper reviews the ski related injuries from the angle of the field-of-play (FOP) medical officer in the 2019 FIS World Cup, expecting to shed lights on the injury prevention and the athlete safeguard in the following competitive winter events.

This paper analyzes the ankle surgery and the rehabilitation program of a top-level badminton athlete. Multi-party consultation was held and an expert support team was set up for the treatment of this athlete's ankle joint injury. The therapist and the surgeon cooperated as a team for the comprehensive treatment plan from multiple angles. The treatment includes the modalities, the analgesia treatment, the use of joint protective devices, the joint mobility treatment, the muscle strength training, the weight-bearing training, the physical training and other treatment. Under a close supervision, the function of the athlete improved gradually. 4 weeks after the surgery, the athlete could bear the full body weight and had a normal gait. 8 weeks after the surgery he returned to training and 14 weeks after the surgery he returned to the competition successfully. In the first match he entered the final. Post-operation rehabilitation programs were practical, effective, and reached the guarantee goals.

The efficacy of the knee arthroscopic debridement for patients with degenerative osteoarthritis of the knee is still a controversial issue. In order to clarify the indications of the knee arthroscopic debridement, the effect of the arthroscopic debridement on the degree of the knee osteoarthritis is studied. A retrospective analysis is made for patients with knee osteoarthritis, after the arthroscopic debridement in the department of orthopedics of Beijing Tiantan Hospital from September 2011 to September 2016. According to the Kellgren-Lawrence (K-L) classification, the knee osteoarthritis patients are divided into four groups from degrees I to IV and are followed up after the surgery. It is found that the Oxford Knee Score (OKS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the Numeric Pain Rating Scale in the four groups are significantly improved post-operatively after 6 months and 1 year. After 3 years post-operatively, for patients of degrees I and II, the scores are also significantly improved. However, no significant difference is observed for patients of degree III and the scores are even decreased for patients of degree IV after 3 year post-operatively. Our study indicates that the arthroscopic knee arthroplasty has a good effect in the early and middle postoperative period for patients of knee osteoarthritis of K-L degrees I and II. For patients of severe osteoarthritis of K-L degrees III and IV, the clinical symptoms can be partially alleviated in the early stage, but the mid-term efficacy is not satisfactory.

The meniscus root tears are a specific type of the meniscal injury, and recently, received more and more attention of researchers. The meniscal root tears either are defined as an avulsion of the insertion of the meniscus attachment or the complete radial tears,located within 1 cm of the meniscus insertion. Biomechanical studies show that the meniscal root injuries interrupt the continuity of the circumferential fibers, and hence lead to failure of the normal meniscal function of converting the axial loads into the transverse hoop stresses. The meniscal root tears can be classified into 5 groups based on the tear morphology. The treatments of the meniscal root tears include the nonoperative therapy, the partial meniscectomy, and the meniscal root repair. The repair techniques have better clinic outcomes and become a research focus recently, including the transtibial pullout technique, the suture anchor repair and the anatomic reinforced medial meniscal root reconstruction with gracilis autograft. As a new technique for treatment of the osteoarthritis of Knee varus, the meniscus posterior root tear repair is combined with a high tibial osteotomy. In this review, we focus on the advances of the anatomy, the biomechanics, the classification system, and the treatment methods for the treatment of posterior meniscal root tears.

This paper is a retrospective study of the clinical outcomes of the arthroscopic acetabular labral repair with suture anchor. The clinical data of patients of the arthroscopic repair with wire anchors due to the acetabular labrum tears from January 2012 to January 2017 are retrospectively analyzed. Before and after the surgery, the patients are evaluated for the physical signs, the pain, the hip function and the degree of cartilage degeneration, with a total of 42 sets of complete clinical data, of an average age of 29 years and an average follow-up time of 31 months. The VAS and Harris scores are improved from the preoperative 4.5±0.92 to 1.6±1.2 and from 56.95±10.6 to 95.95±5.4, respectively. And the Harris score is greater than 90 points in 39 cases, with an excellent rate of 92.8%. The difference between the preoperative and postoperative VAS and Harris scores is statistically significant(P<0.001). However, there is no significant difference between the postoperative and preoperative cartilage degeneration (P=0.083). It is shown that the acetabular labrum arthroscopic repair with suture anchor is effective and has a critical therapeutic value for the acetabular labrum injury.