负荷条件下前交叉韧带的股骨重建位置

目的　探讨模拟生理负荷条件下前交叉韧带股骨等距重建位置。方法　 7具新鲜冷冻膝关节标本 ,在前交叉韧带股骨附着区取 5点以及胫骨附着区中点分别钻骨隧道 ,通过钢丝和等距测量器施加初负荷 ,检测膝关节屈曲过程中胫骨和股骨隧道间的距离变化。结果　膝关节 0°～ 90°屈曲过程中 ,股骨韧带附着区中点、后点和下点与胫骨附着区中点间呈等距变化 ,而股骨韧带附着区前点和上点与胫骨附着区中点间距离变化超过生理等距界限。结论　股骨韧带附着区后点和下点是理想的前交叉韧带股骨等距重建点。股骨韧带附着区中点、后点和下点的连线构成了前交叉韧带的股骨等距重建区。     

前交叉韧带重建术中隧道定位对移植物等距特性影响的研究

目的探讨前交义韧带(ACL)重建术中股骨和胫骨隧道定位变化对移植物等距特性的影响。方法选用10具正常新鲜冷冻尸体膝关节标本,在股骨取3个定位点,第一个定位点位于右膝11点(左膝1点)过顶点前方5～6 mm处,作为前束点；第二点位于前束点前5 mm处,作为误差点；第三点位于屈膝90°时,ACL附着区长轴与经股骨-胫骨接触点的垂直线的交点,作为后束点。在ACL胫骨附着区的前后径上取3个定位点,一个位于原ACL附着区中心,称为中心点；一个位于中心点后5 mm处,称为5 mm后点；一个位于中心点后10 mm处,称为10 mm后点。模拟ACL重建步骤,经各个股骨和胫骨定位点分别钻直径为2 mm的骨隧道,通过测量钢丝和等距测量仪来检测膝关节屈曲过程中各个股骨隧道内口相对于各个胫骨隧道内口的距离变化。结果相对于某一个固定的股骨隧道内口,胫骨隧道内口的前后移位变化对移植物等距特性的影响差异无显著性意义(P＞0．05)；相对于某一个固定的胫骨隧道内口,股骨隧道内口位置的变化对移植物等距特性的影响差异有极显著性意义(P＜0．01)。从膝关节完全伸直到极度屈曲的过程中,如果股骨隧道内口选择在前束点,则两内口间移植物长度变化在生理等距范围内；若选择在误差点,则两内口间移植物长度变化表现为超出生理等距范围的延长；若选择在后束点,则两内口间移植物长度变化表现为超出生理等距范围的短缩。结论ACL重建时,胫骨隧道内口在ACL附着区中心与棘间区后缘之间的前后移位对移植物等距特性无明显影响,股骨隧道内口的移位对移植物的等距特性有明显影响。     

前交叉韧带重建术中胫骨侧止点无撞击区的定位研究

目的探讨前交叉韧带(ACL)重建术中胫骨隧道无撞击重建区的定位。方法选用10具正常新鲜冷冻尸体膝关节标本,膝关节完全伸直时,标记髁间窝顶延长线和ACL胫骨附着处的交点。膝关节屈曲90°时,测量ACL胫骨附着处上标记点与ACL前缘间的距离及标记点与胫骨棘间区后缘间的距离。然后,再测量标记点前部分的前后径、后部分的前后径和内外径,并计算后部分的面积。结果由ACL胫骨附着处前缘到胫骨棘间区后缘的前后径平均为(21.40±1.17)mm。ACL胫骨附着处标记点前部分的前后径平均为(8.90±0.74)mm(占总前后径的41.59%)。胫骨附着处标记点后部分的前后径平均为(12.50±0.85)mm(占总前后径的58.41%),内外径平均为(10.65±0.97)mm,面积平均为(133.80±21.01)mm2。结论ACL胫骨附着处上标记点的后部分是胫骨隧道无撞击区,位于胫骨棘间区的后缘中点与该点前12.50mm之间,在该区域行ACL重建可以避免移植物与髁间窝顶部的撞击。绝对撞击区位于ACL胫骨附着部前缘与其后8.90mm之间,应尽量避免在此区域内定位胫骨隧道。     

前交叉韧带重建术的精确定位

目的探讨前交叉韧带（ＡＣＬ）重建的定位方法。方法取２０例新鲜或冷冻保存的尸体膝关节,通过做骨道至股骨和胫骨的ＡＣＬ附丽区,穿以钢丝并被动屈曲膝关节,测得其长度参数。用自行研制的等距测尺,连续观察测值的变化。结果在３０°～１２０°屈曲过程中,前上区纤维由短变长,前方制约作用逐渐增加;后上及中心区纤维的长度变化很小;前下区及后下区纤维由长变短,前方制约作用逐渐减少。结论股骨附丽区后上区和中心区应视为ＡＣＬ的重建位置。在陈旧损伤附丽区标志不明时,可使用等距测尺来决定重建位置中心。     

X线动态测量膝前交叉韧带长度变化

目的 在侧位X线片下分别测定膝关节屈曲90°及过伸位时前交叉韧带(ACL)股骨等距点(i点)到胫骨等距点(T点)的距离,并比较在2种体位下其长度的变化,评估关节镜结合X线透视双监视法行ACL等距解剖重建的影像学效果.方法 门诊随机抽取50名志愿者,行膝关节侧位X线片检查,在PX电子系统下找到屈曲90°及过伸位ACL的i点和T点,测量两点间距离,并比较在屈伸过程中两点长度的变化.结果 屈曲90°时i点到T点距离的95%可信区间为(25.43±0.455)mm,最大值为29.22 mm,最小值为20.29 mm;过伸位时i点到T点距离的95%可信区间为(26.90±0.436)mm,最大值为29.76 mm,最小值为23.10 mm;过伸位与屈曲90°时两点间距离之差的95%可信区间为(1.47±0.204)mm,最大值为3.33 mm,最小值为0.47 mm.结论 术前X线片测量及术中关节镜结合X线透视双监视法可根据不同个体的差异对ACL的股骨等距点及胫骨等距点行准确定位,可达到生理性等距重建的要求,同时对设备的要求不高,可在大多数医院开展.     

单束单隧道与双束双隧道重建膝前交叉韧带的生物力学对比研究

[目的]研究双束股骨双隧道法重建前交叉韧带(ACL)恢复膝关节前后方向稳定性的能力,并与单束单隧道重建法进行生物力学性能的比较。[方法]应用跟腱分别采用双束股骨双隧道、单前内侧束和单后外侧束三种方法对10个新鲜尸体膝关节进行前交叉韧带重建。术后分别于膝关节屈曲0°、15°、30°、60°及90°时对胫骨施行±100 N的作用力,测量胫骨相对于股骨移动的距离。[结果]在屈膝角度较小(0°~30°)的情况下,单前内侧束重建法术后胫骨的移动距离与完整标本接近(P>0.05);但屈曲超过30°,特别是超过60°后,单前内侧束重建法术后胫骨移动的距离明显大于完整标本(P<0.05)。在屈膝角度<60°的情况下,单后外侧束重建法胫骨移动的距离明显大于完整标本(P<0.05):但屈曲超过60°胫骨移动的距离与完整标本接近(P>0.05);在膝关节的整个屈曲范围(0°~90°)内,双束股骨双隧道重建法术后胫骨移动的距离与完整标本接近(P>0.05)。[结论]双束股骨双隧道重建法,在膝关节的整个屈曲范围(0°~90°)内,比单束股骨单隧道重建法能更有效的恢复膝关节的稳定性。     

膝后交叉韧带双束重建术中股骨隧道定位的计算机辅助设计研究

目的 :采用现实虚拟互动技术及有限元分析法,探讨膝关节后交叉韧带双束重建术中股骨隧道合理定位及重建术后移植物固定膝关节力学响应。方法:取新鲜冰冻膝关节标本5具,用实验与计算机仿真相结合的方法,重建膝关节三维计算机模型,以实验获得的外部结构运动指标操纵此模型,真实再现人体膝关节屈伸运动。分析模型内部股骨与胫骨关节面在此运动过程中的空间位置变化情况,分别在后交叉韧带前外侧束(ALB)和后内侧束(PMB)股骨端附丽区选取前、后、中、近、远10个测试点,选取胫骨端止点中点,利用软件Geomagic计算连接两关节面各两点间的长度变化。将模型导入软件Ansys,采用四面体单元建立起股骨-胫骨复合体的有限元模型,模拟人体行走中单腿着地情况对模型施加自身体重冲击载荷,分析关节面的受力情况。结果:计算机还原出各运动角度下膝关节骨性结构的空间形态,软件Geomagic的几何计算功能能准确测量股骨各点与胫骨止点间在关节内的长度变化,ALB和PMB相同测试点在不同角度所得关节面两点间长度变化平均值间有显著性差异(P<0.05);且同一角度不同测试点所得数据间亦有显著性差异(P<0.05)。ALB各点中以A2变化最小(1.35±0.19)mm,A1变化最大(5.41±1.22)mm,A2和A3点比较,差异无统计学意义(P=0.913>0.05);PMB各点中以B3点变化最小(1.95±0.04)mm,B1变化最大(5.23±2.21)mm,只有A2、A3和B3点变化范围在2 mm以内。结论 :通过计算机技术能够建立可供分析测量的膝关节模型,能准确的对交叉韧带的长度进行测量。在后交叉韧带双束重建中,前外侧束应以其股骨附丽区上缘的中点(即近测试点)为中心钻孔;后内侧束应以其股骨附丽区上缘(即近测试点)为中心钻孔建立股骨骨隧道。模型为进一步评价重建等长点偏差对术后移植物固定力学环境影响的研究提供基础。     

双股腘绳肌腱重建解剖学形态的前交叉韧带

目的探讨经双股骨和3个胫骨隧道用双股腘绳肌腱移植,重建解剖学形态前交叉韧带的可行性和效果。方法使用关节镜技术准确的确立出前交叉韧带起止点位置,并钻取2个股骨和3个胫骨隧道,将双股腘绳肌腱分为3束重建解剖学形态的前交叉韧带。结果所有病例随访8~15个月,膝关节功能恢复满意。结论前交叉韧带重建技术更能发挥膝关节生物力学性能,具有广泛的应用前景。     

胫骨隧道位置对前交叉韧带重建术后膝关节稳定性的影响

<正>关节镜前交叉韧带(anterior cruciate ligament,ACL)重建是骨科常见手术之一,生理性等长重建使移植物在膝关节屈伸过程中所受的张力相近。隧道制备中关于股骨隧道定位等距性及生物力学的研究较多,但有关胫骨隧道定位对生物力学影响的报道较少。     

虚拟现实互动技术在交叉韧带等长重建计算机辅助设计中的应用

目的 利用虚拟现实技术还原膝关节骨性结构在屈伸运动过程中的三维空间形态，为观测膝关节面交叉韧带附丽区的相对位置变化和进一步研究前、后交叉韧带等长重建最佳等长点提供计算机辅助设计新方法。方法 采用实验与计算机仿真相结合的方法，对新鲜人体膝关节标本进行屈伸运动实验，并通过激光三维扫描方法记录、计算膝关节的空间活动指标，然后重建膝关节计算机三维模型。通过实验中的空间活动指标控制此模型虚拟运动，再现膝关节各屈伸角度下股骨、胫骨和腓骨的空间位置。结果 计算机还原出各运动角度下膝关节骨性结构（股骨、胫骨及关节面）的空间形态，利用软件Geomagic的几何计算功能可分别测量模型中各个运动状态交叉韧带附丽区两点间的三维空间距离。讨论本研究方法可以真实地记录和再现膝关节三维运动过程，从空间结构上更精确、合理地寻找重建等长点，对膝关节交叉韧带手术重建有重要临床意义。     

Measurement of changes in distance between the femoral and the tibial drill holes for the anterior cruciate ligament reconstruction

We have developed an experimental system in which a new Gallium-Indium containing transducer can continuously measure the changes of separation distances between the femoral and tibial points. The measurements provides information for the attachment location in the anterior cruciate ligament (ACL) reconstruction and used for various combinations of extra-articular and intra-articular methods. At the first experiment, the distance between each pair of points at the level of the capsule for fifteen combinations during simple flexion-extension knee motion were measured on six cadaveric knees. At the next experiment, in an ACL-deficient knee the distances of ten combinations in the intra-articular method were measured. These results indicated that for an isometric placement the combination of the center of tibial insertion and the postero-proximal of the femoral origin of the ACL appeared to furnish a better location for intraarticular reconstruction. No combination was recommended for extraarticular reconstruction.     

Femoral tunnel placement in anterior cruciate ligament reconstruction: rationale of the two incision technique

Endoscopic anterior cruciate ligament (ACL) reconstruction can be performed through one-incision or two-incision technique. The current one-incision endoscopic ACL single bundle reconstruction techniques attempt to perform an isometric repair placing the graft along the roof of the intercondylar notch, anterior and superior to the native ACL insertion. However the ACL isometry is a theoretical condition, and has not stood up to detailed testing and investigation. Moreover this type of reconstruction results in a vertically oriented non-anatomic graft, which is able to control anterior tibial translation but not the rotational component of the instability. Femoral tunnel obliquity has a great effect on rotational stability. To improve the obliquity of graft, an anatomical ACL reconstruction should be attempt. Anatomical insertion of ACL on the femur lies very low in the notch, spreading between 11 and 9–8 o'clock position and the center lies lower than at 11 o'clock position. Femoral aiming devices through the tibial tunnel aim at an isometric placement, and they do not aim at an anatomic position of the graft. Also, a placement of tunnel in a position of 11 o'clock is unable to restore rotational stability. The two-incision technique, with the possibility to position femoral tunnel independently by tibial tunnel, allows us to place femoral tunnel entrance in a position of 10 'clock that can most accurately reproduce the anatomic behaviour of the ACL and can potentially improve the response of the graft to rotatory loads. This positioning results in a more oblique graft placement, avoiding problem related to PCL impingement during knee flexion. Further studies are required to understand if this kind of reconstruction can ameliorate proprioception as well as clinical outcome at a long-term follow-up.     

ACL reconstruction by patellar tendon

In 50 knees the length of the anterior cruciate ligament (ACL), the patellar tendon, and the distance between the tibial tuberosity and the femoral origin of the ACL were evaluated by means of three-dimensional magnetic resonance imaging (MRI), which permits subsequent reconstruction of any sectional view. The measurements showed that the patellar tendon was always markedly longer than the ACL (mean 14.4 mm), but always shorter than the distance between the tibial tuberosity and the femoral insertion of the ACL (mean 19.2 mm). The mean lengths of the ACL and the patellar tendon were 38.2 mm and 52.6 mm, respectively. The mean distance between the femoral ACL origin and the tibial insertion of the patellar tendon was 71.8 mm. These results demonstrate that a distally based patellar tendon autograft alone (with the patellar bone block but without extension into the periosteum of the patella or the quadriceps tendon) cannot be placed anatomically correctly to the isometric femoral insertion of the ACL. When the patellar tendon is used for ACL reconstruction, it must be implanted as a free autograft. Nevertheless, considerable variations of length must be taken into account.     

Effects of femoral tunnel placement on knee laxity and forces in an anterior cruciate ligament graft.

The purpose of this study was to measure the effects of variation in placement of the femoral tunnel upon knee laxity, graft pretension required to restore normal anterior-posterior (AP) laxity and graft forces following anterior cruciate ligament (ACL) reconstruction. Two variants in tunnel position were studied: (1) AP position along the medial border of the lateral femoral condyle (at a standard 11 o'clock notch orientation) and (2) orientation along the arc of the femoral notch (o'clock position) at a fixed distance of 6-7 mm anterior to the posterior wall. AP laxity and forces in the native ACL were measured in fresh frozen cadaveric knee specimens during passive knee flexion-extension under the following modes of tibial loading: no external tibial force, anterior tibial force, varus-valgus moment, and internal-external tibial torque. One group (15 specimens) was used to determine effects of AP tunnel placement, while a second group (14 specimens) was used to study variations in o'clock position of the femoral tunnel within the femoral notch. A bone-patellar tendon-bone graft was placed into a femoral tunnel centered at a point 6-7 mm anterior to the posterior wall at the 11 o'clock position in the femoral notch. A graft pretension was determined such that AP laxity of the knee at 30 deg of flexion was restored to within 1 mm of normal; this was termed the laxity match pretension. All tests were repeated with a graft in the standard 11 o'clock tunnel, and then with a graft in tunnels placed at other selected positions. Varying placement of the femoral tunnel 1 h clockwise or counterclockwise from the 11 o'clock position did not significantly affect any biomechanical parameter measured in this study, nor did placing the graft 2.5 mm posteriorly within the standard 11 o'clock femoral tunnel. Placing the graft in a tunnel 5.0 mm anterior to the standard 11 o'clock tunnel increased the mean laxity match pretension by 16.8 N (62%) and produced a knee which was on average 1.7 mm more lax than normal at 10 deg of flexion and 4.2 mm less lax at 90 deg. During passive knee flexion-extension testing, mean graft forces with the 5.0 mm anterior tunnel were significantly higher than corresponding means with the standard 11 o'clock tunnel between 40 and 90 deg of flexion for all modes of constant tibial loading. These results indicate that AP positioning of the femoral tunnel at the 11 o'clock position is more critical than o'clock positioning in terms of restoring normal levels of graft force and knee laxity profiles at the time of ACL reconstruction.     

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。     

Reconstructive interventions of the posterior cruciate ligament--experimental studies of isometric aspects. Part II: Studies of the posterior cruciate ligament replacement model]

Isometric positioning of the posterior cruciate ligament (PCL) graft is important for successful reconstruction of the PCL-deficient knee. This study documents the relationship between graft placement and changes in intra-articular graft length during passive range of motion of the knee. In eight cadaveric knees the PCL was identified and cut. The specimens were mounted in a stabilizing rig. PCL reconstruction was performed using a 9-mm-thick synthetic cord that was passed through tunnels 10 mm in diameter. Three different femoral graft placement sites were evaluated: (1) in four specimens the tunnel was located around the femoral isometric point, (2) in two specimens the tunnel was positioned over the guide wire 5 mm anterior to the femoral isometric point, (3) in two specimens the tunnel was positioned over the guide wire 5 mm posterior to the isometric femoral point. In all knees only one tibial tunnel was created around the isometric tibial point. The location of the isometric points was described in part I of the study. The proximal end of the cord was fixed to the lateral aspect of the femur. Distally the cord was attached to a measuring unit. The knees were flexed from 0 degree to 110 degrees, and the changes in the graft distance between the femoral attachment sites were measured in 10 degrees steps. Over the entire range of motion measured the femoral tunnels positioned around the isometric point produced femorotibial distance changes of within 2 mm. The anteriorly placed tunnels produced considerable increases in femorotibial distance with knee flexion, e.g. about 8 mm at 110 degrees of flexion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Anterior cruciate ligament reconstruction with preservation of remnant bundle using hamstring autograft: technical note

During an arthroscopic examination for an anterior cruciate ligament (ACL) reconstruction, there is a relatively thick remnant ACL tibial stump attached to the posterior cruciate ligament (PCL) or rarely remained between the femur origin and the tibia insertion. We thought that preservation of the remnant ACL original bundle might promote graft healing or be helpful in preserving the proprioception and function to stabilize the knee. Therefore, we established a remnant preservation procedure without additional instruments during an ACL reconstruction using a bio-cross pin (RIGIDfix system: Mitek, Johnson & Johnson, USA) for the femoral tunnel fixation. The remnant ACL was sutured (usually three stitches) using a suture hook (Linvatec, Largo, FL), and both ends of the sutures were pulled to the far anteromedial (AM) portal. These sutures protected the remnant tissue during the ACL reconstruction because medial traction of these sutures can provide a wide view during the reconstruction. After the femoral and tibial tunnel formation, these sutures were pulled out to the inferior sleeve of the cross pin using a previously inserted wire loop via an inferior sleeve. After graft passage, a superior cross pin was first fixed and tibial fixation was then performed. Finally, inferior cross pin fixation was performed and ties were made at the entrance of the inferior cross pin.     

Definitive landmarks for reproducible tibial tunnel placement in anterior cruciate ligament reconstruction

The purpose of this prospective study was to define constant anatomic intraarticular and extraarticular landmarks that can be used as definative reference points to reproducibly create a tibial tunnel for anterior cruciate ligament (ACL) reconstruction that (1) results in an impingement-free graft in full extension without an intercondylar roofplasty; (2) positions the tibial tunnel's intraarticular orafice sagittally central in the original ACL insertion without visually guessing; (3) positions the tibial tunnel such that the sagittal tunnel-plateau angle is parallel with the sagittal intercondylar roof-plateau angle in full extension to minimize shear seen by the graft at the tibial tunnel inlet, and by doing so; (4) maximizes tunnel length to avoid patellar tendon graft-tunnel length mismatch allowing for endosteal interference screw fixation on both sides of the joint. Anatomic dissections in 50 knees showed the ACL sagittal central insertion point on the intercondylar floor averages 7 mm (range 7 to 8 mm) sagittally anterior to the anterior margin of the posterior cruciate ligament (PCL) with the knee flexed 90° such that the PCL may be used as a reliable reference landmark for locating the ACL sagittal central insertion. This constant relationship was found to be independent of knee size. Extraarticularly, beginning the tibial tunnel sagittally 1 cm above the superior (sartorial) border of the pes anserinus insertion and coronally 1.5 cm posteromedial from the medial margin of the tibial tubercle along the superior surface of the pes, directed toward the sagittal central ACL insertion, led to a sagittal tunnel-plateau angle that averaged 68°(range 64° to 72°) with a corresponding tunnel length that averaged 58 mm (range 50 to 65 mm) in 23 knees. This data correlated well with data obtained clinically in a series of 50 consecutive ACL reconstructions using intraarticular PCL and extraarticular pes anserine-medial tibial tubercle referenced tibial tunnels in which postoperative full extension lateral radiographs confirmed a sagittal tunnel-plateau angle parallel or near parallel with the intercondylar roofplateau angle in all cases averaging 68° ± 3.8°. Tibial tunnel length averaged 60 mm (range 52 to 66 mm) and in no case was there a patellar tendon autograft-tunnel length mismatch.