股骨Blumensaat线的MRI测量及其对重建ACL的意义

目的应用MRI对股骨Blumensaat线的测量,为重建前交叉韧带(anterior cruciate ligament,ACL)提供参考。方法通过选择100例正常的膝关节伸直位磁共振检查结果,在适当的切面上绘制Blumensaat线延长线与胫骨平台的交点,测量其在胫骨矢状径位置及其与后交叉韧带(posterior cruciate ligament,PCL)的距离,并与ACL胫骨侧生理止点中心和PCL的距离比较。结果 Blumensaat线延长线与胫骨平台的交点在胫骨矢状径上距前缘(51.9±7.3)%,与PCL距离(14.2±2.5)mm,较ACL生理止点中心靠后。结论为避免髁间窝前方撞击,重建ACL胫骨侧止点定位于胫骨平台生理性止点中心后方或PCL前方8～10mm,个别人需更后方。     

膝关节伸直位X线片测量在前交叉韧带损伤诊断中的价值

目的探讨膝关节伸直位X线片在前交叉韧带(ACL)损伤诊断中的价值。方法51例单纯、单侧膝关节ACL损伤的病人,双膝关节侧位X线片并进行测量。①测量Blumensaats线的延长线与胫骨平台相交点B到胫骨平台前缘A的距离和胫骨平台前后缘的距离AC,并计算AB与AC的比值;②测量股骨髁间窝顶点Blumensaats线的延长线与胫骨平台的夹角(顶-平台角);③测量股骨干纵轴与胫骨平台的夹角(股骨-平台角)。结果①健侧Blumensaats线的延长线与胫骨平台相交点B到胫骨平台前缘A的距离为12.21mm±2.02mm,顶-平台相交率为22.17%±3.86%,患侧Blumensaats线的延长线与胫骨平台相交点B到胫骨平台前缘A的距离为18.09mm±3.56mm,顶-平台相交率为31.33%±5.34%,两者比较有显著的统计学意义(P<0.01);②顶-平台角健侧为56.06°±4.23°,患侧为60.10°±4.81°,有统计学意义(P<0.01);③股骨-平台角健侧为97.92°±3.68°患侧为98.19°±3.44°,经统计学处理,P>0.05,没有统计学意义。结论X线平片在ACL损伤诊断中有明显的实用价值。在动力位的膝关节X线侧位平片上,ACL损伤侧膝关节的顶-平台相交率和顶-平台角均高于健侧。X线片测量方法易于推广,因此可以作为ACL损伤病人的常规检查方法和诊断依据。     

CT在诊断膝关节交叉韧带断裂中的价值

目的　探讨CT对于确定交叉韧带断裂部位的价值。方法　对有膝关节外伤史、膝关节检查有可疑交叉韧带损伤者 ,分别摄双侧膝关节屈膝 90°前、后抽屉试验位X线侧位片。于X线片上 ,从股骨髁的中心点向胫骨平台前、后缘连线做垂线将后者分为前后两段 ,任何一段比健侧同段长 5mm以上则为阳性。即前段长者为前交叉韧带完全断裂 ,后段长者为后交叉韧带完全断裂。之后作膝关节部位的薄层CT扫描 (层厚、层距均为 1 5mm) ,观察胫骨上端前、后方有无撕脱性小骨块 ,以及股骨髁间窝处股骨外髁内侧或股骨内髁外侧有无撕脱性小骨块。结果　从 1994年 1月～ 1999年 11月按上述方法共诊断交叉韧带完全断裂者 18例。其中 ,前交叉韧带于胫骨止点处撕脱者 1例 ;后交叉韧带于胫骨止点处撕脱者 2例 ;前交叉韧带于股骨外侧髁起点处撕脱者 2例 ;后交叉韧带于股骨内侧髁起点处撕脱同时伴内侧副韧带股骨附着部撕脱性骨折 1例 ;1例膝关节脱位者伴腓骨小头撕脱性骨折及腓总神经损伤。其余病例自韧带实质部断裂。所有病例均经手术修复或重建 ,除 1例术前诊断为单纯前交叉韧带实质部完全断裂 ,而术中发现前交叉韧带实质部断裂约 90 %外 ,其余病例的术前诊断与术中所见均完全吻合。结论　CT对于确定交叉韧带断裂部位具有重要价值     

三维CT重建及MRI检查在复杂性胫骨平台骨折中应用的病例对照研究

目的:评价三维CT重建及MRI在复杂性胫骨平台骨折中的临床应用价值。方法:自2004年3月至2009年1月收治复杂性胫骨平台骨折71例,在常规行普通X线片检查的基础上,同时行MDCT扫描并三维重建及MRI检查,其中行双切口单钢板法治疗24例,男14例,女10例;年龄19～56岁,平均33.6岁;平均随访时间31.4个月;行膝内外侧双切口双钢板法治疗21例,男12例,女9例,年龄21～53岁,平均33.2岁,平均随访时间28.4个月;行膝前正中直切口双钢板法治疗26例,男17例,女9例,年龄22～57岁,平均35.3岁,平均随访时间23.6个月。对骨折定位、骨折粉碎程度、骨折移位程度、骨缺损程度显示的满意度及关节面塌陷、膝关节交叉韧带、侧副韧带及半月板损伤的阳性率进行比较。结果:X线片、MDCT及MRI的满意度评分分别为:骨折部位,(1.04±0.20)、(1.82±0.38)、(1.12±0.33)分;骨折粉碎程度,(0.81±0.51)、(1.92±0.26)、(0.83±0.60)分;骨折移位情况,(1.23±0.48)、(1.92±0.26)、(0.46±0.58)分;骨缺损程度,(0.36±0.51)、(1.55±0.79)、(0.26±0.53)分;关节面塌陷,16、61、12例;交叉韧带伤,3、10、17例;半月板伤,0、0、6例;侧副韧带伤,1、1、8例。MDCT在显示胫骨平台关节面是否塌陷、交叉韧带胫骨附着点撕脱骨折、胫骨平台骨折位置、骨折粉碎程度及骨折移位程度上较X线片及MRI满意。MRI在显示膝关节交叉韧带、侧副韧带、半月板损伤、关节面软骨是否剥脱及骨挫伤方面较X线片及CT满意。结论:MDCT并三维重建与MRI检查进一步丰富了基于X线片表现的胫骨平台骨折Schatzker分型,MDCT与MRI检查有助于复杂性胫骨平台骨折的精确诊断与合理治疗方案的确定,MDCT与MRI有助于发现膝关节及关节周围隐匿性损伤,减少误漏诊。     

前交叉韧带胫骨平台止点的MRI测量及临床意义

目的应用MRI测量前交叉韧带（ACL）胫骨平台止点,为临床生理等长重建ACL提供参考。方法选择100例正常的膝关节磁共振检查结果,在适当的切面上绘制并测量胫骨平台前缘至后交叉韧带（PCL）前缘之间直线距离（AP）、在该径线上ACL胫骨侧止点中心至胫骨平台前缘之间距离（IA）、ACL胫骨止点中心至PCL前缘切线距离（DL）,并计算IA/AP的比值。结果IA为（19.5±2.8）mm,AP为（38.5±3.6）mm,IA/AP为（50.6±4.8）%,DL为（16.3±2.0）mm。结论MR I可用于测量ACL胫骨侧止点,重建ACL胫骨侧止点定位于胫骨平台中点稍后方可能更为合理。     

MRI测量ACL与胫骨平台夹角改变对诊断“PCL止点愈合型”ACL断裂的意义

目的探讨MRI测量前交叉韧带(ACL)与胫骨平台夹角改变在诊断"后交叉韧带(PCL)止点愈合型"ACL断裂中的应用。方法纳入自2014-01—2018-12诊治的22例"PCL止点愈合型"ACL断裂作为观察组,纳入同期22例正常膝关节MRI影像资料作为对照组。比较2组MRI图像上ACL与胫骨平台的夹角。结果观察组中有16例在首次MRI诊断报告中未提及ACL断裂,6例首次MRI诊断为ACL可疑损伤,假阴性率高达72.7%。观察组ACL与胫骨平台的夹角为(17.3±5.6)°,对照组为(36.2±1.6)°;观察组ACL与胫骨平台夹角较对照组明显减小,差异有统计学意义(P 0.01)。结论MRI测量ACL与胫骨平台夹角变小提示存在"PCL止点愈合型"ACL断裂,可作为临床诊断的一种间接指标。     

前交叉韧带重建术中胫骨骨道定位的应用解剖研究

[目的]探究前交叉韧带(anterior cruciate ligament,ACL)于胫骨止点处的解剖形态以及测量髁间窝顶线与胫骨平台交汇点至后交叉韧带前缘的距离对胫骨骨道定位的解剖学意义,为ACL重建术提供理论依据。[方法]选取新鲜成人膝关节标本8例,仔细剔除关节周围肌肉、后关节囊等结构,保留前后交叉韧带及两侧侧副韧带,保证膝关节正常屈伸范围。在屈伸膝关节时按照ACL纤维张力区将其分为前内束和后外束,在胫骨附着处将ACL切断制备ACL损伤模型。用测量工具和Phontoshop软件获取ACL基本解剖参数以及髁间窝顶线与胫骨平台的交汇点、ACL前缘、ACL胫骨止点的中心点分别至后交叉韧带前缘的距离。[结果]ACL平均体部直径为(11.21±0.76)mm,ACL在胫骨止点处的平均最大横径为(11.34±0.79)mm,平均最大前后径为(16.54±0.82)mm。前内束和后外束在胫骨止点处的平均面积分别为(113.35±29.65)mm~2和(83.29±16.99)mm~2。髁间窝顶线与胫骨平台的交汇点、ACL前缘以及ACL胫骨止点的中心点至后交叉韧带前缘的距离分别为(12.13±0.96)mm,(21.14±0.83)mm和(8.82±0.77)mm。[结论]利用胫骨平台骨道定位ACL在股骨的解剖止点现实可行,在ACL重建术中具有重要意义。     

外踝骨折后三角韧带损伤程度的X线与MRI比较研究

目的 探讨急性外踝骨折后X线片与MRI评价三角韧带损伤程度的影像学诊断价值.方法 总结医院PACS系统中41例急性外踝骨折(排除合并内踝骨折病例)的X线片和MR影像资料,于踝穴位X线片上测量踝内侧间隙(medial clear space,MCS)宽度,应用MR影像对三角韧带深层(胫距后韧带)及浅层(胫弹簧韧带和胫跟韧带)损伤进行评价分级,统计分析MCS与三角韧带损伤程度的相关性;分别记录以X线片和MRI为参考的全部病例Lauge-Hansen分型.结果 MCS与三角韧带损伤等级呈正相关,经ROC曲线分析,判定三角韧带完全断裂(深层和浅层同时)的MCS最适临界值和深层单独完全断裂的MCS最适临界值均为7.85 mm;而判断浅层完全断裂的MCS最适临界值是6.48mm;以MRI为金标准,所有病例Lauge-Hansen分型的准确性为58.5％,但预测三角韧带断裂的准确性达82.9％,只是难以区分深层和(或)浅层断裂.结论 急性外踝骨折后即使未出现内踝骨折,也常伴有三角韧带损伤,X线片仍是踝关节骨折评价的首选检查技术,而MR检查是明确三角韧带损伤程度的敏感辅助检查技术.     

后交叉韧带胫骨止点骨折的手术治疗

2002年10月～2005年6月,我院共收治单纯后交叉韧带(PCL)胫骨止点撕脱骨折12例,均在早期采用后侧入路行PDLLA可吸收螺钉内固定术,疗效满意。1材料与方法1.1病例资料本组12例,男8例,女4例,年龄21～47岁。均为闭合性损伤。合并其它肢体骨折4例,另作相应处理。手术指征:抽屉试验( ),膝关节侧位X线片可见PCL胫骨止点骨折并向后移位,或膝关节MRI显示PCL胫骨止点骨折移位超过5mm。1.2手术方法连续硬膜外麻醉。于膝关节后方作“S”形切口,长8～10cm,探查可见PCL明显松弛,其胫骨止点撕脱骨折并向后移位,确认胫骨髁间隆突骨折面,骨折复位后用…     

腓骨头至后交叉韧带胫骨部高度差距的测量及其意义

[目的]通过MRI图像上测量腓骨头与后交叉韧带胫骨止点间的垂直距离,为术前评估全膝关节置换手术中后交叉韧带损伤的概率提供参考。[方法]随机选取86侧正常成人膝关节,行膝关节核磁共振扫描,获得图像经Photoshop CS5软件处理,测量腓骨头至后交叉韧带止点的距离,并分析年龄和性别因素对其影响。[结果]腓骨头与后交叉韧带胫骨部最高点的垂直距离为(8.6±3.5)mm,腓骨头至后交叉韧带胫骨部最低点的垂直距离为(2.8±2.8)mm,在不同年龄、性别之间均无明显差异。[结论]腓骨头是术前预测后交叉韧带胫骨止点位置的可靠参考标志,TKA术前应常规行膝关节X线片检查,评估后交叉韧带损伤概率。     

Single compared to double-bundle PCL reconstruction using allograft tissue

This study compares the results of arthroscopic transtibial tunnel single-bundle and double-bundle posterior cruciate ligament (PCL) reconstructions using allograft tissue in PCL-based multiple ligament injured knees. Ninety consecutive PCL reconstructions are evaluated: 45 single-bundle and 45 double-bundle reconstructions. All PCL reconstructions were performed using the arthroscopically assisted transtibial tunnel PCL reconstruction technique using fresh frozen allograft tissue from the same tissue bank. Achilles tendon allograft was used for the anterolateral bundle; tibialis anterior allograft was used for the posteromedial bundle. The knees were evaluated postoperatively, comparing the single-bundle results to the double-bundle results, with KT-1000 arthrometer (Medmetric Corporation, San Diego, CA) testing, three different knee ligament rating scales, and Telos stress radiography (Austin Associates, Fallston, MD). Both the single-bundle and the double-bundle PCL reconstruction surgical techniques using allograft tissue provide successful results in the PCL-based multiple ligament injured knee when evaluated with stress radiography, arthrometer measurements, and knee ligament rating scales.     

The axial view in evaluating tibial translation in cases of insufficiency of the posterior cruciate ligament.

The purpose of this report is to present a new radiological method of diagnosis and evaluation of posterior instability using the patellofemoral axial view. During a period of 22 months, we performed clinical and radiological assessments on 20 patients (6 acute and 14 chronic) with isolated posterior instability caused by posterior cruciate ligament (PCL) rupture and on 20 patients with normal knees. The radiological examination included stress radiographs using the Telos device (Telos, Griesheim, Germany) as well as a modification of the routine axial patellofemoral view. Both diagnosis and quantification of the posterior tibial translation was possible in all cases by measuring, on the axial view, the distance between the anterior edge of the tibial plateau and the center of the femoral groove (trochlea). Clinical examination, conventional radiography, KT-1000 arthrometry, stress radiography at 90 degrees and at 20 degrees of flexion, and magnetic resonance imaging all assist in diagnosing a PCL tear. This new radiographic technique is simple, fast, and consistently effective both in patients with acute and those with chronic PCL tears, as well as in those who have undergone PCL reconstruction.     

A comparison of arthroscopic single- and double-bundle posterior cruciate ligament reconstruction: review of 20 cases

In the study reported here, we evaluated postoperative outcomes of arthroscopic posterior cruciate ligament (PCL) reconstruction using hamstring tendons and compared single- and double-bundle reconstructions. Twenty patients with isolated PCL tears and multiligamentous knee injuries were enrolled. Single-bundle (group S) and double-bundle (group D) reconstructions were applied to 10 patients each. Posterior tibial translation was measured using stress radiography before surgery and 2 years after surgery. Second-look arthroscopy was also performed in each knee. Two years after surgery, mean side-to-side differences in posterior tibial translation of groups S and D were 3.4 mm (SD, 3.0 mm) and 4.9 mm (SD, 2.8 mm), respectively. There was no significant difference in short-term stability between the 2 groups. Second-look arthroscopy showed 3 ruptures of the posteromedial bundle in the double-bundle technique.     

Posterior cruciate ligament replacement with a two-strand quadriceps tendon-patellar bone autograft and a tibial inlay technique

BACKGROUND: Complete ruptures of the posterior cruciate ligament alter knee kinematics and may result in functional limitations with sports and daily activities. We prospectively evaluated the functional results and knee stability after posterior cruciate ligament replacement with use of a two-strand quadriceps tendon-patellar bone autograft and a tibial inlay technique. METHODS: Nineteen patients were followed for a mean of thirty-five months postoperatively. All had a chronic knee injury, and eight had additional ligament reconstructions. The results were measured with stress radiography, arthrometric testing, and two validated knee-rating instruments. RESULTS: Eighteen patients rated the knee condition as improved. Before surgery, eleven patients had pain with daily activities, but only one had such pain at the time of the latest follow-up. Significant improvements were noted for pain, swelling, giving-way, walking, climbing stairs, squatting, running, jumping, and twisting and turning (all p < or = 0.05). Eleven patients returned to low-impact sports, and two patients were able to participate in strenuous sports without problems. At the time of the latest follow-up, stress radiography revealed that fourteen knees had < or =5 mm of increased posterior tibial translation between the reconstructed and the contralateral side, three knees had 6 to 10 mm, and two knees had >10 mm. No knee had an infection, permanent limitation of knee motion, or patellar fracture. CONCLUSIONS: Posterior cruciate ligament replacement produced reasonable subjective, functional, and objective results in this group of complex, chronic knee injuries. The tibial inlay approach was useful in nine revisions in which prior tibial tunnels had to be avoided.     

Knee Kinematics in Anterior Cruciate Ligament-Substituting Arthroplasty With or Without the Posterior Cruciate Ligament

Few studies have compared functional kinematics in knees using identical prostheses with or without the posterior cruciate ligament (PCL). This study contrasted in vivo knee kinematics with an anterior cruciate ligament-substituting arthroplasty with and without PCL retention. We hypothesized that knees without PCLs would exhibit less femoral posterior translation, and consequently less maximum knee flexion. Fifty-six knees were studied using dynamic radiography at least one year post-surgery, with twenty-seven knees retaining the PCL and twenty-nine knees having the PCL sacrificed. Consistent with our hypothesis, PCL-sacrificing knees showed more anterior femoral condylar positions. Contrary to our hypothesis, PCL-sacrificing knees demonstrated greater knee flexion during kneeling (122° versus 115°). Contracted PCLs in severely deformed knees likely were the cause of limited flexion in some retaining knees.     

Arthroscopically assisted combined anterior and posterior cruciate ligament reconstruction in the multiple ligament injured knee: 2- to 10-year follow-up

Purpose: This study presents the 2- to 10-year results of 35 arthroscopically assisted combined anterior cruciate ligament and posterior cruciate ligament (ACL/PCL) reconstructions evaluated preoperative and postoperatively using Lysholm, Tegner, and Hospital for Special Surgery knee ligament rating scales, KT-1000 arthrometer testing, stress radiography, and physical examination. Type of Study: Case series. Methods: This study population included 26 men and 9 women with 19 acute and 16 chronic knee injuries. Ligament injuries included 19 ACL/PCL/posterolateral instabilities, 9 ACL/PCL/medial cruciate ligament (MCL) instabilities, 6 ACL/PCL/posterolateral/MCL instabilities, and 1 ACL/PCL instability. All knees had grade III preoperative ACL/PCL laxity and were assessed preoperatively and postoperatively with arthrometer testing, 3 different knee ligament rating scales, stress radiography, and physical examination. Arthroscopically assisted combined ACL/PCL reconstructions were performed using the single-incision endoscopic ACL technique and the single femoral tunnel–single bundle transtibial tunnel PCL technique. PCLs were reconstructed with allograft Achilles tendon (in 26 cases), autograft bone–patellar tendon–bone (BPTB) (in 7 cases), and autograft semitendinosus/gracilis (in 2 cases). ACLs were reconstructed with autograft BPTB (16 cases), allograft BPTB (12 cases), Achilles tendon allograft (6 cases), and autograft semitendinosus/gracilis (1 case). MCL injuries were treated with bracing or open reconstruction. Posterolateral instability was treated with biceps femoris tendon transfer, with or without primary repair, and posterolateral capsular shift procedures as indicated. Results: Postoperative physical examination revealed normal posterior drawer/tibial step-off in 16 of 35 (46%) knees. Normal Lackman and pivot-shift test results were found in 33 of 35 (94%) knees. Posterolateral stability was restored to normal in 6 of 25 (24%) knees, and tighter than normal knee results were found in 19 of 25 (76%) knees evaluated with the external rotation thigh foot angle test. In this group, 30° varus stress testing was normal in 22 of 25 (88%) knees, and grade 1 laxity was found in 3 of 25 (12%) knees. 30° valgus stress testing was normal in 7 of 7 (100%) surgically treated MCL tears, and in 7 of 8 (87.5%) brace-treated knees. Postoperative KT-1000 arthrometer testing mean side-to-side difference measurements were 2.7 mm (PCL screen), 2.6 mm (corrected posterior), and 1.0 mm (corrected anterior) measurements, a statistically significant improvement from preoperative status (P = .001). Postoperative stress radiographic side-to-side difference measurements measured at 90° of knee flexion and 32 lb posteriorly directed proximal force were 0 to 3 mm in 11 of 21 (52.3%) knees, 4 to 5 mm in 5 of 21 (23.8%), and 6 to 10 mm in 4 of 21 (19%) knees. Postoperative Lysholm, Tegner, and HSS knee ligament rating scale mean values were 91.2, 5.3, and 86.8, respectively, showing a statistically significant improvement from preoperative status (P = .001). Conclusions: Combined ACL/PCL instabilities can be successfully treated with arthroscopic reconstruction and the appropriate collateral ligament surgery. Statistically significant improvement is noted from the preoperative condition at 2- to 10-year follow-up using objective parameters of knee ligament rating scales, arthrometer testing, stress radiography, and physical examination. Postoperatively, these knees are not normal, but they are functionally stable. Continuing technical improvements will probably improve future results.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 18, No 7 (September), 2002: pp 703–714     

Inlay技术在后十字韧带和后外复合体损伤中的应用

目的 介绍inlay技术的手术适应证及早期临床疗效.方法 完成后十字韧带inlay重建及后外复合体重建手术24例,男18例,女6例;年龄19～52岁,平均33.8岁.在后十字韧带胫骨解剖附丽区制备20 mm×10 mm×8 mm骨槽,将移植物带骨块一端嵌入骨槽,用两枚空心螺钉垫片固定.关节镜监视下采用自外向内的方法制备后十字韧带股骨侧隧道,植入移植物的另一端,采用挤压螺钉固定.术前、后均行IKDC主、客观评分、查体、KT-1000测量、应力x线片测量.结果 24例患者获得随访,随访时间12～33个月,平均26.9个月.术前IKDC评分为C或D;后抽屉试验均＞2+,其中3+及4+者占83%(20/24),平均3+;KT-1000平均13.7 mm(10～29 mm);应力X线片测量平均13.9 mm(10～29 mm).术后IKDC评分为:A,5膝;B,18膝;D,1膝;后抽屉试验结果为:0(正常)5例,1+11例,2+7例,3+以上1例,平均1+,较术前平均改善2+;KT-1000平均4.8 mm(-4～18.2 mm),较术前平均改善8.9 mm;应力X线片测量平均5.3 mm(-1.7～18.2 mm),较术前平均改善8.6mm.1例失败.膝关节活动度屈膝受限平均7.5°(0°～25°).无伸膝受限的病例.结论 Inlay技术可用于重建损伤的后十字韧带和后外复合体.     

Multiple-ligament injured knee

Objective: To explore the clinical characteristic of the multiple-ligament injured knee and evaluate the protocol, technique and outcome of treatment for the multipleligament injured knee. Methods: From October 2001 to March 2005, 9 knees with combined anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears in 9 patients were identified with clinical and arthroscopic examinations. Of them, 5 knees were combined with ruptures of posteromedial corner (PMC) and medial collateral ligament (MCL), 4 with disruptions of posterolateral corner (PLC), 2 with popliteal vascular injuries and 1 with peroneal nerve injuries. Six patients were hospitalized in acute phase of trauma,2 received repairs of popliteal artery and 4 had repairs of PMC and MCL. Reconstructions of ACL and PCL with autografts under arthroscope were performed in all patients at 4 to 10 weeks after trauma, including reconstruction of PLC with the posterior half of biceps femoris tendon tenodesis in 4 patients and reconstructions of PMC and MCL with femoral fascia in 1 patient. Results: No severe complications occurred at early stage after operation in the 9 patients. All of them were followed up for 10-39 months with an average of 23. 00 months±9. 46 months. Lysholm score was 70-95 with an average of 85.00±8.29. International Knee Documentation Committee (IKDC) score was from severely abnormal (Grade D) in 9 knees at initial examination to normal (Grade A) in 2 knees, nearly normal (Grade B) in 6 knees and abnormal in 1 knee at the last follow-up. Of the 9 patients, 7 returned to the same activity level before injury and 2 were under the level. Conclusions:The multiple-ligament injured knee with severe instability is usually combined with other important structure damages. Therefore, careful assessment and treatment of the combined injuries are essential. Reconstructions of ACL and PCL under arthroscope, combined with repairs or reconstructions of the extraarticular ligaments simultaneously or in stages, have advantage of minimal trauma in surgery and satisfactory outcome.     

应力后沉征诊断单纯后交叉韧带损伤

目的　对 18例经手术证实为急性单纯后交叉韧带损伤行应力下胫骨后移的定量分析 ,以评价应力后沉征在诊断后交叉韧带损伤中的作用。方法　术前在麻醉和屈膝 90°行双膝应力 (15kg)下的摄片并定量分析 ,得出双膝应力前后的胫骨后移情况。结果　患膝较健侧有明显的胫骨后移 ,患膝应力下平均胫骨后移较非应力下提高 1+级。结论　在诊断急性后交叉韧带损伤时 ,麻醉下和屈膝 90°位应力后沉征较后沉征和后抽屉试验准确和灵敏 ,应力摄片示胫骨后移有明显意义的升高。要理解屈膝 90°位和麻醉下行后沉征和后抽屈试验的重要性     

Posterior cruciate ligament and coupled posterolateral instability of the knee

We wanted to investigate the role of the posterior cruciate ligament (PCL) in the knee's posterolateral stability and the magnitude of the coupled posterolateral instability with the knee examined at 90 degrees of flexion. The coupled posterolateral instability of the knee was studied by selective ligament cutting in cadaver knees set at 90 degrees. The coupled posterolateral displacement after cutting the PCL was 173% of the intact knee. With an intact PCL, the coupled posterolateral displacement after cutting the popliteus tendon and lateral collateral ligament with the knee at 90 degrees of flexion was 299% of the intact knee. When the PCL was cut together with the popliteus tendon and lateral collateral ligament, the coupled posterolateral displacement was 367%. The PCL plays an important role in the posterolateral stability of the knee, and its injury may cause mild (< 5 mm) to moderate (5-10 mm) posterolateral instability. Thus, in a knee with posterolateral instability, injury of the PCL must be considered. With an intact PCL, the posterolateral instability was very recognizable with the knee at 90 degrees of flexion, and injury to the PCL further increased the posterolateral instability and caused posterior translation of the knee. Therefore, examination for posterolateral instability of the knee should also be performed with the knee at 90 degrees of flexion, which is much easier to perform in a clinical setting. A positive posterior translation rather than posterolateral instability at different knee positions differentiates knees with combined PCL and posterolateral instability from knees with isolated posterolateral instability.