半腱肌股薄肌腱横杆悬挂固定法重建膝关节前交叉韧带

目的介绍关节镜下横杆悬挂固定法(Arthrex TransFixⅡ法)固定移植的半腱肌腱、股薄肌腱重建膝关节前交叉韧带的方法。方法2003-01~2005-12,采用半腱肌、股薄肌腱横杆悬挂固定法重建膝关节前交叉韧带43例。其中,男性32例,女性11例。年龄19~67岁,平均年龄26.8岁。平均病程8.9个月。移植物股骨端行横杆悬挂法固定,胫骨端齿压钉固定。结果43例患者中,40例获得随访,随访时间6~18个月,平均12.3个月。随访病例术前Lysholm评分为(49.8±2.7)分,随访时Lysholm评分(91.7±1.8)分,两者相比有显著性差异(P<0.05)。结论关节镜下半腱肌、股薄肌腱横杆悬挂固定法重建膝关节前交叉韧带,是一种微创、疗效确切的方法。     

How Important is the Tunnel Position in Outcomes Post-ACL Reconstruction: A 3D CT-Based Study

BackgroundDrilling the femoral and tibial tunnels at their anatomical locations are critical for good outcomes and involve seeing the footprints well. We intended to compare two techniques of drilling the tunnels and the patient-reported outcomes and knee stability of patients undergoing single bundle ACL reconstruction using 3D CT to evaluate if the tunnels were anatomical or not.Materials and MethodsSixty single bundle ACL reconstructions were analyzed, 30 each with Technique A and B. Pre-operative and after a minimum 27 month follow-up Lysholm, IKDC, Tegner score, hop test, and Lachman test were noted. 3D CT was done to classify femoral tunnels positions as being well placed, slightly or grossly misplaced and tibial tunnels as optimal or suboptimal and compared.ResultsSixty ACL reconstructions had full follow-up with a mean follow-up of 34 months. There was no significant difference between tunnel positions between the two techniques. Well-placed femoral tunnel had better Lysholm score (62.2 ± 16.2 v/s 48.5 ± 17.2, p 0.002) and IKDC score (62.5 ± 14.3 v/s 52.7 ± 15.1, p 0.012).). Those who had their surgeries within 3 months of their injury had better hop test (4.4 ± 0.9 v/s 3.9 ± 1, p 0.034) and IKDC scores (62.5 ± 15.8 v/s 33.2 ± 13.8, p 0.026) as compared to those that had surgery done after 3 monthsConclusionTibial tunnel positions were optimal in most cases and did not differ between the two techniques. Well-placed femoral tunnels and surgeries done within 3 months of the injury produced best results.     

A Prospective Observational Study on Short-Term Functional Outcome of Arthroscopic Anterior Cruciate Ligament Repair of Proximal Tears Using Knotless Single Suture Anchor Technique

PurposeTo assess the clinical outcomes in patients with anterior cruciate ligament (ACL) proximal tears undergoing arthroscopic primary repair with knotless single suture anchor technique.MethodsThe first twenty-two consecutive patients with proximal ACL tears (Sherman types I and II and high-grade partial tears) treated with arthroscopic primary repair with single suture anchor technique were evaluated until 6 months post-operatively. Patients were evaluated with validated functional outcome measures (IKDC and Lysholm scores) and clinical tests for ACL stability.ResultsAt 6-month follow-up, 91% of patients (n = 20) achieved excellent outcome measures for IKDC and Lysholm scores and had complete stability of the ACL to clinical testing. Two patients with poor outcomes at six weeks; one with subjective instability and the other underwent revision surgery represented a failure rate of 9%. The median Lysholm score was 96 (IQ range, 96–100) and median IKDC subjective score was 87.40 (IQ range, 78.20–88.50) at 6-month follow-up. The improvement in Lysholm and IKDC scores over a period of six months post-operatively was statistically significant when compared to preoperative scores (p ≪ 0.0001). Maximum improvement in clinical outcomes is achieved in the first 6 weeks post-surgery with a slower increase thereafter, a time interval which may be considered as a figurative yield point for future work in this field.ConclusionArthroscopic ACL primary repair with knotless single suture anchor technique provides excellent short-term clinical outcomes in a carefully selected subset of patients with proximal ACL tears. More powered and longer duration studies are needed to understand longer term outcomes.Level of EvidenceLevel IV, therapeutic case series.     

Is there significant variation in the material properties of four different allografts implanted for ACL reconstruction

The aims of our study were to: (1) determine if there are differences in the material properties of tendon obtained from implanted tibialis anterior, achilles, bone-patella- bone and tibialis posterior allografts; (2) determine the variability in material properties between the implanted specimens. A total of 60 specimens were collected from fresh frozen allografts implanted at ACL reconstruction. Specimens collected included 15 tibialis anterior, 15 tibialis posterior, 15 achilles and 15 bone-patella-bone tendons. Each specimen was mounted in a custom made cryogrip. The mounted specimens were loaded onto a MTS Testline servo-hydraulic testing machine in a uni-axial tensile test configuration. Specimens were subjected to a strain rate of 5% per second until the ultimate tensile stress (UTS), failure strain and high strain modulus was calculated for each specimen after being normalized for specimen dimensions. Individual material properties were tested using one way analysis of variance (ANOVA) and post hoc Tukey’s B test with a P value of <0.05 considered significant. Homogeneity of variance was assessed using the Levene’s test. As a result, no significant difference was found between all four grafts with regards to UTS, failure strain or high strain linear modulus. The UTS was plotted against the modulus demonstrating a linear relationship which is typical of soft tissues. Significant variability in the results were observed. In conclusion, there was no significant statistical difference between the material properties of the four tendon allografts tested. But significant variability in results was observed within groups and between groups, which may provide one explanation for the range of results in allograft ACL reconstruction reported in the literature.     

自体髌腱、单双束腘绳肌腱重建ACL术后临床疗效比较

目的 探讨关节镜下不同术式重建前交叉韧带（ACL）后膝关节运动功能恢复情况,为临床术式选择提供依据.方法 144例ACL损伤患者应用自体骨-1/3髌腱-骨（B-PT-B）、单隧道单束腘绳肌腱（ST/G）和单隧道双束腘绳肌腱（ST/G）3种术式关节镜下行ACL重建,定期随访,应用Lysholm评分和Tegner活动水平评分进行膝关节功能评估,比较3种术式临床疗效.结果 ①各组患者膝关节Lysholm评分和Tegner活动水平评分在术后均较术前改善（P＜0.05）.②术后任何时间ST/G组Lysholm评分、Tegner评分高于B-PT-B组（P＜0.05）,但单隧道单束组、单隧道双束组组间比较差异无显著性（P＞0.05）.结论 ①3种术式均能明显改善膝关节运动功能,但在恢复膝关节稳定性及术后客观体征改善方面,近期ST/G组优于B-PT-B组.②单隧道单束和单隧道双束ST/G组术后恢复膝关节运动功能方面差异无显著性.③关节镜下自体ST/G单隧道单束重建ACL能够有效恢复膝关节前后向及旋转稳定性,缩短手术时间,减少创伤,节约成本,是一种相对安全有效的手术方法.     

一种虚拟企业访问控制模型

在分析了虚拟企业访问控制需求的基础上，扩展传统的基于角色的访问控制模型(RBAC)，定义了一种跨企业RBAC(CE—RBAC)模型，该模型能在虚拟企业环境中方便地实现跨企业的安全访问控制。     

膝关节韧带损伤的CT与MRI影像表现及诊断价值

目的探讨并对比CT和MRI在诊断膝关节前交叉韧带(ACL)撕裂的应用价值及影像学表现。方法回顾性分析我院63例膝关节损伤患者的CT和MRI检查资料,对比评价结果及影像学表现。结果以关节镜诊断为"金标准",MRI诊断ACL撕裂准确率为95.23%,显著高于CT诊断率82.54%,具有统计学意义(P0.05)。经MPR技术处理后,ACL撕裂CT表现为韧带挛缩、增宽,交叉韧带中断裂处呈低密度;ACL撕裂急性期MRI表现为T1低信号,T2高信号;慢性期为长T1长T2信号,韧带增粗、扭曲;断端边缘不清晰或有明显断痕,信号异常。结论 MRI诊断膝关节ACL撕裂中的准确性高于CT,可为临床诊治提供更丰富的信息。     

ACL Injury prevention in female athletes: review of the literature and practical considerations in implementing an ACL prevention program

Female athletes are at 3.5 times risk of sustaining a non-contact ACL injury compared with males. Research has shown that this gender discrepancy results from differences in neuromuscular adaptations and biomechanics related to landing techniques. Studies have examined the preventative effect of ACL prevention programs, which have been designed to address these risky neuromuscular and biomechanical patterns. We review the key studies on ACL prevention in female athletes and summarize the critical components of ACL prevention strategies that have been shown to successfully decrease ACL injury risk. We also discuss recommendations and practical considerations in the implementation of ACL prevention programs in various community settings.