关节镜下单骨道双束和单骨道单束重建前交叉韧带疗效的初步对比研究

目的:前瞻性对比研究单骨道双束和单骨道单束腘绳肌腱重建前交叉韧带的疗效差异。方法:2011年10月至2012年3月,共48例初次前交叉韧带断裂患者入选本研究,随机分为单骨道双束组(n=24)和单骨道单束组(n=24),分别采取关节镜下单骨道双束和单骨道单束重建前交叉韧带手术技术,移植物均使用自体腘绳肌腱。两组胫骨骨道均用Tibial Intrafix固定,单骨道双束组股骨骨道用Femoral Intrafix固定,而单骨道单束组股骨骨道用Endobutton固定。术后随访分别采用IKDC、Lysholm和Tegner评分进行主观膝关节功能评价,采用KT-2000测量客观评估稳定性。结果:48例患者均获随访,平均随访时间(14.71±1.69)个月。两组功能评分显示,术后IKDC、Lysholm和Tegner评分较术前均显著改善,但组间无显著性差异。两组术后客观稳定性评估较术前均显著提高,但组间无显著差异。在134N拉力下KT-2000测量侧侧差值:单骨道双束组屈膝30°时为(1.44±1.28)mm,屈膝90°为(1.15±1.30)mm;单骨道单束组屈膝30°时为(1.63±1.15)mm,屈膝90°为(1.31±1.26)mm。结论:单骨道双束腘绳肌腱重建前交叉韧带能够很好恢复膝关节前向稳定性,手术操作简便,固定牢固,近期疗效满意;但与单骨道单束重建前交叉韧带相比,膝关节主观功能评分和客观稳定性评估均无明显差别,需进一步研究。     

后内束减张经胫骨骨道双束重建后交叉韧带

目的:评估采用后内束减张技术经胫骨骨道双束重建后交叉韧带的初步临床效果。方法:2005年7月至2008年6月,关节镜下后内束减张技术经胫骨骨道双束重建后交叉韧带的24名患者纳入本研究。围手术期观察止血带时间和手术并发症。所有患者平均随访37.0个月(至少24个月),随访内容包括术后膝关节IKDC功能评分、Lysholm评分以及KT-2000膝关节后向松弛度检查。结果:手术平均止血带时间为92分钟,未出现并发症。术后膝关节检查IKDC标准分级结果:A级8例、B级13例、C级3例;Lysholm评分平均89.8±2.8(85～95);双侧膝关节后向KT-2000差值为(2.1±1.3)mm。结论:后内束减张技术经胫骨骨道双束重建后交叉韧带可有效改善膝关节后向稳定性并获满意临床效果。     

胫骨后倾角对前交叉韧带及膝关节稳定性影响的三维有限元分析

目的:探讨胫骨平台后倾角对前交叉韧带及膝关节稳定性的生物力学影响。方法:选择一名健康志愿者行左侧膝关节CT及MRI扫描,测量胫骨平台后倾角为7°。将扫描数据导入Mimics软件,获得骨、软骨、半月板、韧带等结构的三维模型,然后利用Geomagic对图像进行修饰,再导入Solidworks软件中建立伸直位膝关节三维模型。利用Solidworks软件建立2°和12°两种不同后倾角的膝关节三维模型。在建立三组膝关节伸直位模型后,每组模型再分别建立屈膝30°和90°的模型。将膝关节不同三维有限元模型导入ANSYS有限元分析软件中,给予加载负荷进行计算分析:伸直位模型胫骨固定,股骨侧给予施加1150 N的垂直负荷;屈膝30°模型胫骨固定,股骨施加750 N垂直负荷及10 N·m的外旋负荷;屈膝90度模型股骨侧固定,胫骨侧施加134 N的前向负荷。在各模型中分析ACL及胫骨-股骨的相对位移。结果:计算机三维有限元分析显示,在伸膝状态下,ACL承受的张力随着胫骨后倾角的增加而增加:PTS为2°时ACL张力为12.195 N,7°时为12.639 N,12°时为18.658 N;胫骨-股骨相对位移:PTS为2°时为2.735 mm,7°时为3.086 mm,12°时为3.881 mm。在屈膝30°的模型中,前叉韧带所承受的最大张力如下:2°时为24.585 N,7°时为25.612N,12°时为31.481 N;胫骨-股骨位移为:2°时为5.590 mm,7°时为6.721 mm,12°时为6.952 mm。在屈膝90°的模型中,前叉韧带所承受的最大张力如下:2°时为5.119 N,7°时为8.674 N,12°时为9.314 N;胫骨-股骨位移为:2°时为0.276 mm,7°时为0.577 mm,12°时为0.602 mm。结论:在膝关节承受应力时,随着PTS的增加,ACL承受的张力和胫骨-股骨之间相对位移都随之增大,较大的PTS可能是ACL损伤的危险因素。     

前交叉韧带缺损的放射学评价

屈膝20度时,膝关节可产生最大的矢向移位。前交叉韧带缺损时,屈膝20度,利用大腿的重量可产生股骨髁相对胫骨平台的后移位,可在X线照片上证实。作者通过正常膝关节与有前交叉韧带缺损关节的X线照片,确定该方法的价值。病人仰卧,小腿吊高30cm,屈膝大约20°,大腿悬空,并在大腿上近髌骨处放一3kg重的沙袋,以增加膝关节移位的力量。这个位置重要的是保持髌骨向上,以避免过度旋转,病人尽可能保持肌肉松弛,防止肌痉挛。暗盒放在膝关节外侧,距管球1m,射线从内侧垂直投照膝关节。完成这一“应力位”后,改标准侧位,靶-片距仍为1m,屈膝20度,射线自上     

自体半腱和股薄肌腱移植双束重建膝关节后外侧角

目的:观察采用自体半腱和股薄肌腱移植双束重建膝关节后外侧角韧带结构的近期临床效果。方法:对21例膝关节后外侧角韧带结构损伤患者(23个膝关节),采用自体半腱和股薄肌腱移植,双束重建膝关节后外侧角韧带结构。自体半腱肌腱移植物经胫骨骨道和腓骨骨道返折分别重建腘肌腱和腘腓韧带,于腘肌腱股骨外侧髁解剖止点处钻孔固定重建的腘肌腱和腘腓韧带;股薄肌腱移植物经腓骨骨道返折重建腓侧副韧带,于腓侧副韧带股骨外侧解剖止点处钻孔固定重建的腓侧副韧带。对于合并交叉韧带损伤者,同期行关节镜下韧带重建术。术后对患者膝关节内翻稳定性和外旋活动度进行至少1年(12~31个月,平均26.7个月)随访,通过Lysholm膝关节评分法评价膝关节术前、术后功能。结果:术后1年以上的回顾性随访中,膝关节完全伸直位无膝内翻不稳定者;屈膝30°位,无膝内翻不稳定者19例,膝内翻Ⅰ度不稳定伴硬性终止点者2例;俯卧位膝关节屈膝30°,所有患者小腿外旋活动均与对侧相同;Lysholm膝关节评分术前平均54.3分,术后平均89.2分。结论:自体半腱和股薄肌腱移植双束重建膝关节后外侧角韧带结构具有移植腱割取创伤小、移植材料理想、解剖等长重建及固定强度高的特点,近期疗效理想。     

核磁图像上后交叉韧带止点位置的测量及临床应用

目的:在核磁共振图像(MRI)上观察和测量后交叉韧带(PCL)止点位置,为PCL重建骨道定位和术后骨道评估提供帮助。方法:选择102例PCL完整的患者,在MRI的SE T1WI序列矢状位图像上,分别测量PCL股骨和胫骨的止点位置和大小,以及胫骨止点中点到胫骨平台的垂直距离。利用术前MRI测量结果指导12例PCL断裂患者重建术中的骨道定位,术后利用CT评估骨道位置。结果:PCL股骨止点位于Blumensaat线的前下二分之一,止点长度为(11.08±1.51)mm,占Blumensaat线的37.55%;胫骨止点位于胫骨斜坡的后下二分之一,止点长度为(12.37±1.98)mm,占斜坡长度的44.48%。从胫骨止点中心点到胫骨平台最高点的垂直距离为(15.21±2.203)mm。利用术前测量结果指导术中骨道定位和术后骨道位置评估,骨道位置正确。结论:术前MRI测量结果,可以指导术中骨道定位,帮助术后骨道位置的评估。     

三维重建CT与X线测量前交叉韧带重建后骨道位置对比研究

目的:探讨三维重建CT(3D-CT)和X线测量前交叉韧带(ACL)重建后骨道位置的准确性。方法:2005年5月至10月,15例ACL损伤患者采用单切口股骨和胫骨单骨道方法重建ACL。术后采用3D-CT观察骨道口与临近骨性解剖标志;观察Endobutton、Endopearl、骨块、可吸收界面挤压螺钉和骨道位置,以及重建后ACL是否与髁间窝撞击。分别使用X线和3D-CT测量骨道位置,胫骨骨道位置测量采用Klos推荐的方法,股骨骨道测量采用Bernard的"四格法"。结果:3D-CT可直观地观察到ACL重建后骨道及相关情况。3D-CT测量胫骨骨道内口位置为43.53%±2.16%(30.0%~59.1%),X线测量胫骨骨道内口位置为41%±6.25%(25%~62%),两种测量结果差异有统计学意义(P<0.05)。3D-CT测量股骨骨道内口位置为37%±4.56%(23.3%~48.1%),X线测量股骨骨道内口位置为34%±7.31%(21%~54%),两种测量结果差异有统计学意义(P<0.05)。提示:3D-CT与X线骨道位置测量结果有差异。     

关节镜下应用LARS人工韧带同时重建前、后交叉韧带

目的 探讨关节镜下应用LARS人工韧带重建前交叉韧带(ACL)、后交叉韧带(PCL)同时损伤的方法及疗效. 方法 关节镜下同时重建13例ACL、PCL损伤的患者,重建材料采用LARS人工韧带.术后随访12～36个月,采用国际膝关节文件编制委员会(IKDC)韧带标准评价表和Lysholm膝关节功能评分表评估患膝功能,通过KT-1000检查膝关节前后松弛度.结果 术后无膝关节感染发生;均无伸膝受限,屈膝活动度105°～125°,平均117°.术后随访时IKDC评分:A类10例(77%),B类3例(23%).屈膝25°位KT-1000检查:双侧膝关节前向松弛度差异＜2 mm 12例,3～5 mm 1例;屈膝70°位检查:＜2 mm 12例,2～4 mm 1例.术前Lysholm膝关节功能评分为(63.8 ±2.9)分(49～69分),终末随访时为(91.1±2.7)分(88～95分),差异有统计学意义(P＜0.01). 结论 关节镜下同时重建膝关节ACL、PCL是目前治疗ACL、PCL同时损伤的一种微创、安全、有效的手术方法,近期疗效佳.     

前交叉韧带重建术移植物止点对术后膝关节屈伸活动影响的临床研究

目的通过研究移植物止点对术后膝关节屈伸活动的影响,寻求前交叉韧带重建中移植物在股骨和胫骨上的最佳止点.方法对39例关节镜下前交叉韧带重建术后的病人摄膝关节正侧位片,测量移植物止点的位置.以术后3周膝关节的主动活动度进行分组.结果①术后3周有30例病人主动屈曲达90°,其股骨止点位于Blumensaat's线后15.62～48.48%(平均31.51%);未达90°的9例病人的止点位于29.03～75.76%(平均57.32%),两组比较差异显著(P＜0.001).②术后3周有7例主动伸直未达0°,其胫骨止点位于胫骨平台的前18.87～34.50%(平均24.14%),32例伸直达0°者的止点位于25.81～44.83%(平均36.03%),两组比较差异显著(P＜0.001).结论术后膝关节的屈曲功能与移植物的上止点关系密切,伸直与下止点相关.最佳股骨止点位于Blumensaat's线后20～40%,髁间窝顶点的外侧部;胫骨止点位于胫骨平台的前30～40%,两个髁间棘之间.     

前交叉韧带重建术中经胫骨的股骨隧道足迹定位方法改进及术后骨道评估

 目的 探讨前交叉韧带重建术中经胫骨的股骨隧道足迹定位方法的改进及术后骨道位置评估。 方法 分析2007 -06至2010-01于武警总医院行自体半腱肌腱和股薄肌腱单束重建前交叉韧带手术患者196例,应用改进的方法进行关节镜下经胫骨的股骨隧道足迹定位,并应用国际膝关节文献委员会（international knee documentation commitee, IKDC）评分及术后MRI行骨道位置评估的资料。 结果 经随访10～36个月,患者的前抽屉试验及Lachman试验均为阴性,IKDC评分情况均较术前差异有统计学意义( P <0.05) ,采用矢状位上关节线与移植肌腱的夹角(the angle between the joint line and the graft on the sagittal view,JGS)和冠状位上关节线与移植肌腱的夹角(the angle between the joint line and the graft  on the coronal image,JGC) ,对术后6个月及正常侧膝关节MRI行骨道位置评估,重建的前交叉韧带的位置与正常对照组的位置差异无统计学意义（ P >0.05）。 结论 单束重建前交叉韧带时,改进的经胫骨的股骨隧道的足迹定位方法是理想的股骨隧道定位方法,患者关节稳定性与功能均得到显著改善;采用JGS和JGC对骨道位置进行评估可较客观、准确地反映股骨隧道定位情况,骨隧道位置与临床效果相关。     

The accuracy of bone tunnel position using fluoroscopic-based navigation system in anterior cruciate ligament reconstruction

Purpose

The first purpose of this study was to examine whether fluoroscopic-based navigation system contributes to the accuracy and reproducibility of the bone tunnel placements in single-bundle anterior cruciate ligament (ACL) reconstruction. The second purpose was to investigate the application of the navigation system for double-bundle ACL reconstruction.

Methods

A hospital-based case–control study was conducted, including a consecutive series of 55 patients. In 37 patients who received single-bundle ACL reconstruction, surgeries were performed with this system for 19 knees (group 1) and without this system for 18 knees (group 2). The positioning of the femoral and tibial tunnels was evaluated by plain sagittal radiographs. In 18 patients who received double-bundle ACL reconstruction using the navigation system (group 3), the bone tunnel positions were assessed by three-dimensional computed tomography (3D-CT). Clinical assessment of all patients was followed with the use of Lysholm Knees Score and IKDC.

Results

Taking 0% as the anterior and 100% as the posterior extent, the femoral tunnels were 74.9?±?3.0% in group 1 and 71.5?±?5.8% in group 2 along Blumensaat’s line, and the tibial tunnels were 42.3?±?1.4% in group 1 and 42.5?±?4.6% in group 2 along the tibia plateau. The bone tunnel positions in group 1 were located significantly closer to the position planned preoperatively and varied less in both femur and tibial side, compared with those without navigation (group 2). (Femur: P?P?Conclusion The fluoroscopic-based navigation system contributed to the more reproducible placement of the bone tunnel during single-bundle ACL reconstruction compared with conventional technique. Additionally, this device was also useful for double-bundle ACL reconstruction.

Level of evidence

Case–control study, Therapeutic study, Level III.     

Rotational and translational laxity after computer-navigated single- and double-bundle anterior cruciate ligament reconstruction

Based on biomechanical cadaver studies, anatomic double-bundle reconstruction of the anterior cruciate ligament (ACL) was introduced to achieve better stability in the knee, particularly in respect of rotatory loads. Previously, the success of ACL reconstruction was believed to be mainly dependent on correct positioning of the graft, irrespective of the number of reconstructed bundles for which computer-assisted surgery was developed to avoid malpositioning of the tunnel. The aim of the present study is to compare rotational and translational stability after computer-navigated standard single-bundle, and anatomic double-bundle ACL reconstruction. The authors investigated 55 consecutive patients who had undergone the single-bundle or double-bundle ACL reconstruction procedure with the use of autogenous hamstring tendon grafts and EndoButton^® fixation, and the patients had been followed for a minimum period of 24 months. Intraoperative, anteroposterior and rotational laxity was measured with the computer navigation system, and compared between groups. Both surgical procedures significantly reduced anteroposterior displacement (AP) and internal rotation (IR) of the tibia compared to the pre-operative ACL-deficient knee (P < 0.05). No significant differences were registered between groups with regard to anteroposterior displacement of the tibia. A significantly greater reduction in internal rotation was noted in the double-bundle group (15.6°) compared to the single-bundle group (7.1°). The IKDC and Lysholm score were significantly higher in the double-bundle group. However, the results were excellent in both groups. The use of a computer-assisted ACL reconstruction, which is a highly accurate method of graft placement, could be useful for inexperienced surgeons to avoid malposition. Whether double-bundle ACL reconstruction, which was associated with improved rotational laxity and significantly better IKDC and Lysholm scores compared to the standard single-bundle ACL reconstruction procedure, provide an influence in terms of avoiding osteoarthritis or meniscus degeneration, long-term results of at least 5 years are needed.     

Transtibial ACL reconstruction technique fails to position drill tunnels anatomically in vivo 3D CT study

Purpose

The purpose of this study was to visualize and quantify the positions of femoral and tibial tunnels in patients who underwent traditional transtibial single-bundle ACL reconstruction, as performed by multiple surgeons, utilizing 3D CT models, and to compare these positions to our previously reported anatomical tunnel positions.

Methods

Fifty-eight knee computed tomography (CT) scans were performed on patients who underwent primary or revision transtibial single-bundle ACL reconstruction, and three-dimensional reconstructions of the CT scans were aligned within an anatomical coordinate system. The position of femoral tunnel aperture centers was measured with (1) the quadrant method and (2) in the anatomic posterior-to-anterior and proximal-to-distal directions. The position of tibia tunnel aperture centers were measured similarly, in the anterior-to-posterior and medial-to-lateral dimensions on the tibial plateau. Comparisons were made to previously established anatomical tunnel positions, and data were presented as “mean value?±?standard deviation (range).”

Results

The location of tibial tunnels was at 48.0?±?5.4% (35.6–59.5%) of the anterior-to-posterior plateau depth and at 47.9?±?2.9% (42.2–57.4%) of the medial-to-lateral plateau width. The location of femoral tunnels was at 55.8?±?8.0% (41.5–79.5%) in the anatomic posterior-to-anterior direction and at 41.2?±?10.4% (15.1–67.4%) in the proximal-to-distal directions. Utilizing a quadrant method, femoral tunnels were positioned at 37.4?±?5.1% (24.9–50.6%) from the proximal condylar surface, parallel to Blumensaat line, and at 11.0?±?7.3% (?6.0–28.7%) from the notch roof, perpendicular to Blumensaat line. In summary, tibial tunnels were positioned medial to the anatomic PL position (p?p?p?Conclusion ACL reconstruction via traditional transtibial technique fails to accurately position femoral and tibial tunnels within the native ACL insertion site. To achieve anatomical graft placement, other surgical techniques should be considered.

Level of evidence

IV.     

Intraoperative evaluation of anteroposterior and rotational stabilities in anterior cruciate ligament reconstruction: lower femoral tunnel placed single-bundle versus double-bundle reconstruction

Twenty-six patients with anteroposterior (AP) laxity of the knee, associated with torn anterior cruciate ligament (ACL), were prospectively randomized for arthroscopic lower femoral tunnel placed single- or double-bundle reconstruction using hamstring tendons. We evaluated AP and rotational stabilities under regular loads (a 100-N anterior load and a 1.5-N m external–internal load) before and after ACL reconstruction, comparing single- and double-bundle reconstruction with our original device for applying quantitative tibial rotation and the navigation system intraoperatively. No significant differences were found between the two groups in AP displacement and total range of tibial rotation at 30° and 60° of knee flexion. We found that a lower femoral tunnel placed single-bundle reconstruction reproduced AP and rotational stability as well as double-bundle reconstruction after reconstruction intraoperatively.     

Long-term results of arthroscopically assisted anatomical single-bundle anterior cruciate ligament reconstruction using patellar tendon autograft: are there any predictors for the development of osteoarthritis?

Purpose

The primary purpose of our study was to analyse the long-term outcome of patients treated for anterior cruciate ligament (ACL) tears by anatomical single-bundle ACL reconstruction with patellar tendon autograft. The secondary purpose was to identify predictive factors for good outcome and occurrence of osteoarthritis.

Methods

Sixty-three patients (m:f = 54:9; mean age at surgery, 27 ± 7 years) treated by ACL reconstruction were evaluated with a mean follow-up of 16 ± 1 years using IKDC2000, the SF36, Lysholm and Tegner score, Knee Society score, visual analogue scale for pain and satisfaction and KOOS. The femoral tunnel position was evaluated according to Sommer. It was also assessed in percentage of the Blumensaat line and the tibial tunnel position in percentage of the total anterior–posterior plateau length. The extent of osteoarthritis was graded according to the Kellgren–Lawrence score.

Results

The total IKDC2000 was normal in 20 (32 %), nearly normal in 29 (46 %), abnormal in 12 (19 %) and severely abnormal in 3 (5 %) of patients. The mean total SF-36 was 89 ± 13, the Lysholm score 95 ± 12, the Knee Society score 191 ± 16 and the total KOOS 84 ± 19. The Tegner score decreased from pre-injury 7(4–10) to 6 (2–10) at follow-up. The Kellgren–Lawrence score was normal in 17 (27 %), suspected osteoarthritis in 25 (40 %), minimal osteoarthritis in 5 (8 %), moderate osteoarthritis in 9 (14 %) and severe osteoarthritis in 3 patients (5 %). The femoral tunnel was in zone A in 43 patients (68 %), in zone B in 16 (25 %) and in zone C in 4 patients (7 %). The femoral tunnel position in percentage of the Blumensaat line was 49 ± 3 (range, 44–57), and the tibial tunnel position in percentage of the total anterior–posterior plateau length was 32 ± 6 (range, 21–46). Patients with meniscal lesion at the time of ACL tear showed significantly less favourable outcomes than those without.

Conclusions

Patients treated by the proposed ACL reconstruction technique showed on average good to excellent long-term results. A meniscal lesion at the time of ACL tear was highly predictive for less favourable outcome.

Level of evidence

IV.     

Tunnel placement in anterior cruciate ligament (ACL) reconstruction: quality control in a teaching hospital

Correct placement of the femoral and tibial bone tunnels is decisive for a successful anterior cruciate ligament (ACL) reconstruction. Our method of tunnel placement was evaluated as part of quality control at a teaching hospital. The emphasis was placed mainly on investigating the influence of surgical experience on tunnel placement, and the effect of tunnel position on the clinical outcome. Seventeen surgeons with different levels of experience (between 0 and >150 ACL reconstructions) performed endoscopic ACL repair in uniform technique from August 2000 to August 2003 on 50 patients (18 women, 32 men, age range 18–43 years). The patients were available to clinical and radiological follow-up after an average of 19 months. The clinical outcome was classified according to the International Knee Documentation Committee (IKDC) standard evaluation form. The femoral tunnel was evaluated according to the quadrant method of Bernard and Hertel; the position of the tibial bone tunnel was assessed according to the criteria of Stäubli and Rauschnig. The IKDC score revealed 47 (94%) patients with a normal (A) or nearly normal (B) knee joint at follow-up. According to the quadrant method, the femoral canal was situated on average at 29% in the saggital plane. The tibial tunnel was situated on average at 43% of the a.p. diameter of the tibial condyle. Statistical analysis of our data showed no significant correlation between tunnel placement and surgical expertise. However, a highly significant correlation was found (α<0.01) between the femoral position of the tunnel in the sagittal plane and the IKDC score. The more anterior the femoral canal, the poorer the IKDC score. The method of tunnel placement in ACL reconstruction being investigated here only showed slight dependence on surgical experience, whereby good short-term clinical outcomes were achieved. Therefore, the method is suitable for application at a teaching hospital. A far too anterior femoral tunnel placement will probably lead to a decline in the clinical result.     

Causes for failure of ACL reconstruction and influence of meniscectomies after revision

The purpose of this multicenter retrospective study was to analyze the causes for failure of ACL reconstruction and the influence of meniscectomies after revision. This study was conducted over a 12-year period, from 1994 to 2005 with ten French orthopaedic centers participating. Assessment included the objective International Knee Documenting Committee (IKDC) 2000 scoring system evaluation. Two hundred and ninety-three patients were available for statistics. Untreated laxity, femoral and tibial tunnel malposition, impingement, failure of fixation were assessed, new traumatism and infection were recorded. Meniscus surgery was evaluated before, during or after primary ACL reconstruction, and then during or after revision ACL surgery. The main cause for failure of ACL reconstruction was femoral tunnel malposition in 36% of the cases. Forty-four percent of the patients with an anterior femoral tunnel as a cause for failure of the primary surgery were IKDC A after revision versus 24% if the cause of failure was not the femoral tunnel (P?=?0.05). A 70% meniscectomy rate was found in revision ACL reconstruction. Comparison between patients with a total meniscectomy (n?=?56) and patients with preserved menisci (n?=?65) revealed a better functional result and knee stability in the non-meniscectomized group (P?=?0.04). This study shows that the anterior femoral tunnel malposition is the main cause for failure in ACL reconstruction. This reason for failure should be considered as a predictive factor of good result of revision ACL reconstruction. Total meniscectomy jeopardizes functional result and knee stability at follow-up.     

No difference in graft healing or clinical outcome between trans-portal and outside-in techniques after anterior cruciate ligament reconstruction

Purpose

The purpose of this study was to compare femoral tunnel geometry including tunnel position, length, and graft bending angle between trans-portal and outside-in techniques in anterior cruciate ligament (ACL) reconstruction and discover whether such differences in tunnel geometry could influence graft healing or clinical outcome.

Methods

Sixty-four patients with anatomical single-bundle ACL reconstruction performed with either trans-portal technique (32 patients, one centre) or outside-in technique (32 patients, the other centre) were included in this retrospective study. Femoral tunnel location and length, and graft bending angle at the femoral tunnel were analysed on 3D CT knee model. The location and length of the femoral tunnel and graft bending angle were compared between the two techniques. All patients underwent MRI scans at around 1 year following ACL reconstruction. It was found that all patients had intact ACL graft on MRI images. On oblique axial image taken after ACL reconstruction to determine graft healing at femoral and tibial tunnels and the intra-articular portion, graft signal intensity ratio was calculated by dividing signal intensity (SI) of the reconstructed ACL by that of posterior cruciate ligament (PCL) in the region of interest selected with Marosis software. Clinical outcomes regarding Tegner activity scores, the International Knee Documentation Committee (IKDC) evaluation scores, Lachman test, and pivot shift test results were also compared between the two groups.

Results

While the location of femoral tunnel was similar to each other in both groups, the femoral tunnel length was longer in the outside-in technique (37.0 vs. 32.4 mm, p = .02). Meanwhile, the outside-in technique showed significantly more acute graft tunnel angle than the trans-portal technique (106.7° vs. 113.8°, p = .01). However, signal intensity ratios of grafts (compared with SI of PCL) were similar in femoral and tibial tunnels and intra-articular portions. Moreover, there were no statistically significant differences in terms of IKDC scores (89.4 vs. 90.5, n.s.) or Tegner activity scores (6.2 vs. 6.4, n.s.) between the two groups. There was no significant difference in measurement of Lachman or Pivot shift test either between the two groups.

Conclusion

Even though the outside-in technique in ACL reconstruction created a more acute femoral graft bending angle and a longer femoral tunnel length than the trans-portal technique, these had no negative effect on graft healing. In addition, trans-portal and outside-in techniques in ACL reconstruction showed similar femoral tunnel positions and clinical outcomes. Acceptable graft healing and clinical outcomes can be obtained for both trans-portal and outside-in techniques in ACL reconstruction.

Level of evidence

III.

     

Calcium phosphate-hybridized tendon grafts reduce femoral bone tunnel enlargement in anatomic single-bundle ACL reconstruction

Purpose

This study aimed to clarify the effect of calcium phosphate (CaP)-hybridized tendon grafting versus unhybridized tendon grafting on the morphological changes to the bone tunnels at the aperture 1 year after anatomic single-bundle anterior cruciate ligament (ACL) reconstruction.

Methods

Seventy-three patients were randomized to undergo the CaP (n = 37) or the conventional method (n = 36). All patients underwent computed tomography (CT) evaluation 1 week and 1 year post-operatively. The femoral and tibial tunnels at the aperture were evaluated on reconstructed 3D CT images. Changes in the cross-sectional area (CSA) and diameters of the femur and the tibia, and the translation rate of the tunnel walls and the morphological changes of both tunnels were assessed.

Results

There was a significant reduction in the increase in the CSA and the anterior–posterior and proximal–distal tunnel diameters on the femoral side in the CaP group as compared with the conventional group. On the femoral side, the translation rate of the posterior wall was significantly larger in the CaP group than in the conventional group, whereas the translation rate of the distal wall was significantly smaller in the CaP group than in the conventional group.

Conclusions

As compared with the conventional method, the CaP-hybridized tendon graft reduced bone tunnel enlargement on the femoral side 1 year after anatomic single-bundle ACL reconstruction due to an anterior shift of the posterior wall and reduced distal shift in the femoral bone tunnel. Clinically, the CaP-hybridized tendon grafts can prevent femoral bone tunnel enlargement in anatomic single-bundle ACL reconstruction.

Level of evidence

I.