Objective:The pain-relieving effect and safety of compound aminopyrine phenacetin tab-lets,tramcontin(tramadol hydrochloride sustained-release tablets)and dolantin in the early stage of au-tologous tendon reconstruction of the anterior cruciate ligament(ACL)of the knee joint were compared.Methods:Retrospective analysis of postoperative pain and drug analgesia in 45 patients performed by the same group from November 2018 to February 2019.The random area group design was divided into two groups according to whether ACL rupture was combined with meniscal injury,group A was 24 patients with ACL reconstruction of knee joint and group B was 21 patients with ACL fracture combined with me-niscus injury.The two groups were divided into three subgroups respectively according to the actual treat-ment of postoperative analgesic drugs received by the patients,including 4 cases of compound aminopy-rine phenacetin tablets,11 cases of oral tramcontin,9 cases of intramuscular dolantin combined with phenergan in group A;3 cases of compound aminopyrine phenacetin tablets,10 cases of oral tramcontin,and 8 cases of intramuscular dolantin combined with phenergan in group B.When the early postoperative patients complain about pain and actively ask for analgesia.When the patients complained about pain af-ter the operation and actively asked for analgesia,they were randomly given painkillers,tramcontin or do-lantin combined with phenergan to relieve pain.Pain visual analogue scale(VAS)was used to evaluate pain relief and observe the occurrence of adverse reactions.Results:There were no significant dif-ferences in gender,age,body mass index,and time of hospital stay between the two groups of patients(P＞0.05).In the patients who used tramcontin and dolantin combined with phenergan to relieve pain judging by VAS score before and 1 h after taking the drug,it was found that the pain situation of the pa-tient was significantly relieved,and the difference before and after taking the drug had statistical signifi-cance(P＜0.05).Pairwise comparisons of the three drugs applied in the two groups showed significantly greater pain relief in the dolantin combined with phenergan group than in the remaining two drugs.There was no significant difference(P＞0.05).Dolantin was prone to nausea and vomiting,but the application of phenergan was also used to reduce side effects.In terms of adverse reactions,only 1 case of nausea oc-curred in the tramcontin group for simple ACL reconstruction,and none of the patients in the other groups showed serious complications and allergic reactions.Conclusion:Whether in cruciate ligament recon-struction alone or combined with meniscus molding or suture,compound aminopyrine phenacetin tablets,tramcontin,dolantin combined with phenergan can effectively relieve pain.Among the three drugs,do-lantin caused the largest pain relief.At the same time,the combination of phenergan effectively reduced the adverse reactions,such as vomiting and nausea,and increased the drug safety.

Objective:To evaluate knee biomechanics of patients about 12 months after anterior cruciate ligament(ACL)reconstruction during cutting and determine the abnormal biomechanical characteristics.Methods:Sixteen males about 12 months after ACL reconstruction were recruited for this study.Three-dimensional kinematic and kinetic data were collected during cutting movement.Knee joint angles and moments were calculated.Paired t-tests were used to compare the differences in knee biomechanics be-tween the surgical leg and nonsurgical leg.Results:The peak posterior ground reaction force(surgical leg:0.380±0.071;nonsurgical leg:0.427±0.069,P=0.003)and vertical ground reaction force(surgical leg:1.996±0.202,nonsurgical leg:2.110±0.182,P=0.001)were significantly smaller in the surgical leg than in the nonsurgical leg.When compared with the uninjured leg,the surgical leg demonstrated a smaller knee flexion angle(surgical leg:38.3°±7.4°;nonsurgical leg:42.8°±7.9°,P＜0.001)and larger external rotation angle(surgical leg:10.3°±2.4°;nonsurgical leg:7.7°±2.1°,P=0.008).The surgical leg also demonstrated a smaller peak knee extension moment(surgical leg:0.092±0.031;nonsurgical leg:0.133±0.024,P＜0.001)and peak knee external rotation moment(surgical leg:0.005±0.004;nonsurgical leg:0.008±0.004,P=0.015)when com-pared with the nonsurgical leg.Conclusion:The individuals with ACL reconstruction mainly showed asymmetrical movements in the sagittal and horizontal planes.The surgical leg demonstrated a smaller peak knee flexion angle,knee extension moment,and knee external rotation moment,with greater knee external rotation angle.

Objective To analyze the risk factors of postoperative joint infection after arthroscopic an-terior cruciate ligament(ACL)reconstruction,so as to provide evidences for prevention.Methods This is a retrospective case control study.Among 20549 arthroscopic anterior cruciate ligament reconstruc-tion performed between year 2002 and 2018,62 was diagnosed as postoperative joint infection,includ-ing 54 males and 8 females,with an average age of 26.5 years.Another 638 without postoperative in-fection was selected using stratified sampling according to the number of operations per year.The gen-eral condition and surgery data of all patients were collected from the electronic medical record sys-tem.Then univariate Logistic regression analysis was conducted to screen risk factors and multivariate analysis was carried out to create a prediction model.Moreover,an artificial neural network(ANN)model was created to predict the probability and compared with Logistic regression model.Results The univariate Logistic regression analysis found 14 factors associated with postoperative joint infection,in-cluding gender,age,height,weight,body mass index(BMI),socioeconomic status,companioned pro-cedure,single or double bundle reconstruction,portal number,tourniquet time,drainage number,pro-phylactic antibiotics,previous knee surgery and companioned illness.The sensitivity,specificity,accura-cy and area under curve of Logistic regression model was 100%,55.6%,60%and 0.843.As for ANN model,the corresponding values were 80%,89.9%,90%and 0.917.Conclusion Risk factors associated with postoperative joint infection include gender,age,BMI,socioeconomic status,surgery date,tourni-quet time,drainage number and previous knee surgery.Both Logistic model and ANN model yield sat-isfying predicting efficacy,with ANN model showing higher accuracy.

The anterior cruciate ligament (ACL) injury is a common sports injury, which can lead to the knee unstable, make it difficult for the patient to return to sports, and cause post-traumatic osteoarthritis. The difficulty of its clinical diagnosis and treatment has always been the focus of sports medicine research. In August 2022, the American Association of Orthopaedic Surgeons updated and published "evidence-based clinical practice guideline on management of ACL injuries (2022 version)" based on the "evidence-based clinical practice guideline on management of ACL injuries (2014 version)". In the prevention, diagnosis and treatment of ACL injuries, the new guideline offers 8 recommendations and 7 options according to different evidence strength. To assist clinicians in the diagnosis and treatment of ACL injuries, this article provides an interpretation of the new guideline. In comparison to the 2014 version, the new guideline does not recommend allografts any more, shortens the time for reconstruction after ACL injury from 5 months to 3 months, adds advice that ACL reconstruction can be combined with anterolateral ligament reconstruction or lateral extra-articular tenodesis, and does not recommend ACL repair. The new guideline also shares many similarities with the domestic "clinical evidence-based guideline for the diagnosis and treatment of anterior cruciate ligament injury (2022 version)", both of which advocate history and physical examination at diagnosis, early reconstruction, the use of autologous bone-patellar tendon-bone or hamstring tendon, and either single-bundle or double-bundle ACL reconstruction. The new ACL guidelines of the American Association of Orthopaedic Surgeons lack specific recommendations on artificial ligaments, techniques for bone tunnel creation, and rehabilitation programs, all of which are of concern to domestic physicians because they are based on evidence-based research from abroad. Therefore, in order to improve the diagnosis and treatment of ACL injuries in China, clinicians should not only follow the new ACL guidelines of the American Association of Orthopaedic Surgeons, but also combine the characteristics of Chinese patients, clinical practice, and pertinent domestic guidelines when diagnosing and treating ACL injuries.

Background::Visual inputs are critical for locomotor navigation and sensorimotor integration in the elderly; however, the mechanism needs to be explored intensively. The present study assessed the gait pattern after cataract surgery to investigate the effects of visual restoration on locomotion.Methods::The prospective study recruited 32 patients (70.1 ± 5.2 years) with bilateral age-related cataracts in the Department of Ophthalmology at Peking University Third Hospital from October 2016 to December 2019. The temporal-spatial gait parameters and kinematic parameters were measured by the Footscan system and inertial measurement units. Paired t-test was employed to compare data normally distributed and Wilcoxon rank-sum test for non-normally distributed. Results::After visual restoration, the walking speed increased by 9.3% (1.19 ± 0.40 m/s vs. 1.09 ± 0.34 m/s, P=0.008) and exhibited an efficient gait pattern with significant decrease in gait cycle (1.02 ± 0.08 s vs. 1.04 ± 0.07 s, P=0.012), stance time (0.66 ± 0.06 s vs. 0.68 ± 0.06 s, P=0.045), and single support time (0.36 ± 0.03 s vs. 0.37 ± 0.02 s, P=0.011). High amplitude of joint motion was detected in the sagittal plane in the left hip (37.6° ± 5.3° vs. 35.5° ± 6.2°, P=0.014), left thigh (38.0° ± 5.2° vs. 36.4° ± 5.8°, P=0.026), left shank (71.9° ± 5.7° vs. 70.1° ± 5.6°, P=0.031), and right knee (59.1° ± 4.8° vs. 56.4° ± 4.8°, P=0.001). The motor symmetry of thigh improved from 8.35 ± 5.30% to 6.30 ± 4.73% ( P=0.042). Conclusions::The accelerated gait in response to visual restoration is characterized by decreased stance time and increased range of joint motion. Training programs for improving muscle strength of lower extremities might be helpful to facilitate the adaptation to these changes in gait.

Objective:To investigate the correlation of isokinetic thigh muscle asymmetry with gait asymmetry at one year after anterior cruciate ligament (ACL) reconstruction.Methods:A retrospective case series analysis was made on 25 patients treated by ACL reconstruction in Third Hospital of Peking University from January 2014 to January 2019. All the subjects were male, aged 17-47 years [(29.4±5.2)years]. Standard rehabilitation treatment procedures were conducted after surgery. The isokinetic muscle strength of the thigh was collected at one year after operation to evaluate knee extensor and flexor concentric strength at 60°/s, 180°/s and 300°/s, and knee extensor and flexor eccentric strength at 60°/s. The maximum concentric and eccentric strength of the knee extensor and flexor were analysed between the injured and intact side. The three-dimensional motion information and ground reaction force was collected during the stance phase of gait, and knee kinematic and kinetic parameters were calculated by inverse dynamics analysis, including the peak flexion moment, peak extension moment, first and second peak adduction moment, peak external and internal rotation moment, peak flexion angle, peak extension angle during the terminal stance phase, flexion angle at heel strike, peak abduction angle, and peak external rotation angle during terminal stance phase. Spearman correlation analysis was used to study the correlation between limb symmetry index (LSI) of isokinetic muscle strength and LSI of gait parameters.Results:One year after ACL reconstruction, the maximum concentric strength of the knee extensor and flexor at 60°/s, 180°/s and 300°/s and maximum eccentric strength of the knee flexor and extensor at 60°/s on the injured side were significantly lower than those on the normal side (all P<0.01). Compared with the intact side, the peak knee extension moment on the injured side was significantly lower during the stance phase of gait ( P<0.01), and the extension angle was insufficient during the terminal stance phase ( P<0.01). There were no significant differences between the injured and intact side in terms of peak flexion moment, first and second peak adduction moment, peak external and internal rotation moment, peak flexion angle, flexion angle at heel strike, peak abduction angle, and peak external rotation angle during terminal stance phase (all P>0.05). One year after ACL reconstruction, Spearman correlation analysis during gait stance phase showed that the LSI of 60°/s concentric strength of the isokinetic knee extensor was significantly related to LSI of peak internal rotation moment ( R=0.42, P<0.05), the LSI of 180°/s concentric strength of the isokinetic knee extensor was significantly related to LSI of peak flexion moment ( R=0.45, P<0.05), the LSI of 180°/s concentric strength of the isokinetic knee flexor was significantly correlated with LSI of peak flexion angle ( R=0.46, P<0.05), the LSI of 300°/s concentric strength of the isokinetic knee extensor was significantly correlated with LSI of peak knee flexion angle ( R=0.42, P<0.05), and the LSI of 60°/s eccentric strength of the isokinetic flexor was significantly correlated with LSI of peak knee flexion angle ( R=0.54, P<0.01). Conclusions:For patients following ACL reconstruction at one year postoperatively, a significant correlation of isokinetic thigh extensor strength asymmetry with peak knee flexion and rotation moment and peak knee flexion angle, and that of isokinetic thigh flexor strength asymmetry with peak knee flexion angle are observed during the stance phase of gait, which suggests that patients with ACL reconstruction still need systematic rehabilitation training one year postoperatively to improve muscle strength and motor function so as to reduce the risk of ACL reinjury and secondary injury.

Management of bone defects caused by fractures，bone tumors or infections is clinically difficult as well as a hot topic in current studies. With further researches over bone defects，the construction of tissue-engineered bone has played a great role in the treatment of bone defects. Blood vessels not only provide the necessary nutritional mineral salts，growth factors，hormones for bone formation，also are able to mediate the interaction among osteoblasts and osteoclasts，osteocytes，bone autonomic nerve and endothelial cells，since bone formation exist spatially and temporally connection with angiogenesis. Therefore，the authors make a systematic literature review on the research progress of the coupling mechanism of angiogenesis and osteogenic differentiation，blood vessels and related signal pathways on osteogenic differentiation and angiogenesis-related molecules in osteogenic differentiation during the process of traumatic bone defects，so as to provide new ideas for the treatment of bone defects.

Objective:To compare the clinical effects of arthroscopic lateral retinacular proximal release and "L" type release for lateral patellar compression syndrome.Methods:Sixty four lateral patellar compression syndrome (LPCS) patients were recruited who had arthroscopic surgery during September 2004 to January 2019 at Department of Sports Medicine,Peking University Third Hospital by the same group of doctors and a retrospective comparative study was conducted accordingly. Among them,24 cases underwent the traditional proximal release of lateral patellar retinaculum (traditional group),including 7 males and 17 females with an age of (42.9±14.6)years(range:23 to 72 years); 40 cases were treated with novel lateral retinacular release of "L" type release revised based on the previous experiences (novel group), consisting of 12 males and 28 females with an age of (54.9±13.1) years (range:28 to 76 years).All the patients participated surveys for the visual analogue scale (VAS),Lysholm score and International Knee Documentation Committee (IKDC) knee function subjective evaluation before and after the operation. The comparison of scores within groups was performed by Wilcoxon test,and comparison between groups was performed by Mann-Whitney U test and Chi-square test. Multivariate analysis was used to evaluate the related factors affecting each score. Results:The follow-up durations of traditional group and novel group were (12.6±1.0) years (range:11.7 to 15.3 years) and (2.2±1.0)years(range:1.0 to 4.4 years) respectively. At the last follow-up,VAS(0(1.0)to 6.0(2.0), Z=-5.471, P<0.01),Lysholm score(98.0(10.0)to 48.0(40.0), Z=-5.511, P<0.01),and IKDC score(82.8(11.2)to 37.4(18.5), Z=-5.444, P<0.01) in novel group were statistically significantly improved,and the postoperative excellent rate of Lysholm score was 97.5% in general. There was no significant difference in the changes of the three scores ( P>0.05) between the traditional group and the novel group. However,20.8% (5/24)patients in the traditional group reported significant weakness of the knee extension after surgery,while no such complain was received in the novel group ( P<0.01).The results of univariate analysis showed that surgical method was a related factor affecting the changes of VAS before and after surgery ( P<0.05).The results of multivariate analysis showed that whether or not with osteoarthritis and operation type were independent factors affecting the changes of Lysholm and IKDC scores ( P<0.05). Conclusions:The long-term effect of arthroscopic lateral retinacular release for the treatment of LPCS is satisfactory. Compared with the traditional proximal release surgery,the "L" type release can effectively avoid the complication of significant weakness of the knee extension significantly.

Objective:To compare the clinical effects of arthroscopic lateral retinacular proximal release and "L" type release for lateral patellar compression syndrome.Methods:Sixty four lateral patellar compression syndrome (LPCS) patients were recruited who had arthroscopic surgery during September 2004 to January 2019 at Department of Sports Medicine,Peking University Third Hospital by the same group of doctors and a retrospective comparative study was conducted accordingly. Among them,24 cases underwent the traditional proximal release of lateral patellar retinaculum (traditional group),including 7 males and 17 females with an age of (42.9±14.6)years(range:23 to 72 years); 40 cases were treated with novel lateral retinacular release of "L" type release revised based on the previous experiences (novel group), consisting of 12 males and 28 females with an age of (54.9±13.1) years (range:28 to 76 years).All the patients participated surveys for the visual analogue scale (VAS),Lysholm score and International Knee Documentation Committee (IKDC) knee function subjective evaluation before and after the operation. The comparison of scores within groups was performed by Wilcoxon test,and comparison between groups was performed by Mann-Whitney U test and Chi-square test. Multivariate analysis was used to evaluate the related factors affecting each score. Results:The follow-up durations of traditional group and novel group were (12.6±1.0) years (range:11.7 to 15.3 years) and (2.2±1.0)years(range:1.0 to 4.4 years) respectively. At the last follow-up,VAS(0(1.0)to 6.0(2.0), Z=-5.471, P<0.01),Lysholm score(98.0(10.0)to 48.0(40.0), Z=-5.511, P<0.01),and IKDC score(82.8(11.2)to 37.4(18.5), Z=-5.444, P<0.01) in novel group were statistically significantly improved,and the postoperative excellent rate of Lysholm score was 97.5% in general. There was no significant difference in the changes of the three scores ( P>0.05) between the traditional group and the novel group. However,20.8% (5/24)patients in the traditional group reported significant weakness of the knee extension after surgery,while no such complain was received in the novel group ( P<0.01).The results of univariate analysis showed that surgical method was a related factor affecting the changes of VAS before and after surgery ( P<0.05).The results of multivariate analysis showed that whether or not with osteoarthritis and operation type were independent factors affecting the changes of Lysholm and IKDC scores ( P<0.05). Conclusions:The long-term effect of arthroscopic lateral retinacular release for the treatment of LPCS is satisfactory. Compared with the traditional proximal release surgery,the "L" type release can effectively avoid the complication of significant weakness of the knee extension significantly.

Objective: To investigate the mid-term efficacy of extracapsular arthroscopic surgery for refractory tennis elbow and explore prognostic factors. Methods: A retrospective study of 38 patients suffered from refractory tennis elbow and underwent extracapsular arthroscopic surgery performed by the same group of doctors during March 2012 to January 2016 at Institute of Sports Medicine, Peking University Third Hospital. There were 15 males and 23 females with age of 44.2 years(range: 32-59 years). Fifteen cases on the left and 23 cases on the right. Visual analogue scale(VAS), Mayo elbow performance score and Disability of Army, Shoulder and Hand (DASH) score were collected preoperatively and postoperatively, and compared by paired-t test. Independent sample t test, χ² test, multivariate logistic regression were used to analyze the relationship between scores and various potential influencing factors. Results: All 38 patients were followed up for 24 months. There was no complication such as infection or nerve injury recorded. VAS decreased from 7.0(1.2) (M(Q_R)) preoperative to 0(1) (Z=-5.40, P=0.00), Mayo increased from 55(26) to 100(0) (Z=-5.38, P=0.00),DASH decreased from 56.7(27.3) to 0.8(5.8)(Z=-5.37,P=0.00). The Mayo elbow performance score was excellent in 36 cases (94.7%) and good in 2 cases (5.3%). Women was significantly associated with poor prognosis. Conclusions The mid-term effect of extracapsular arthroscopic treatment of refractory tennis elbow is satisfactory with few postoperative complications. Women was associated with poor prognosis.