Bone tunnel enlargement after anterior cruciate ligament reconstruction with semitendinosus tendon using Endobutton fixation on the femoral side

We evaluated 29 knees with a minimum follow-up of 2 years after anterior cruciate ligament (ACL) reconstruction using doubled autogenous semitendinosus tendons. On the femoral side, a 5-mm Mersilene tape (Ethicon, Norderstedt, Germany) with an Endobutton (Acufex Microsurgical, Mansfield, MA) was used. The tendon was fixed on the tibial side with two staples. Regarding the IKDC score, 66% of the patients were graded as normal or nearly normal. The anterior laxity side-to-side difference (KT 1000, man-max-drawer) was under 3 mm in 55% and under 5 mm in 90%. Radiographs taken in the lateral and anteroposterior projections of the knee showed sclerotic bone tunnel margins. The diameter of the bone tunnels were measured, corrected for magnification, then compared with the original reamed diameter to determine any change in size. Enlargement of at least 2 mm was identified in 72% of the femoral tunnels and 38% of the tibial tunnels. No correlation was found concerning the enlargement of the tunnel and the IKDC score or the residual joint laxity. We conclude that using an Endobutton-Mersilene construct in ACL reconstruction leads to femoral and tibial bone tunnel enlargement at follow-up of 2 years. (Arthroscopy 1998 Nov-Dec;14(8):810-5.)     

Use of growth factors in ACL surgery: preliminary study

Abstract There is no general consensus on the use of growth factors (GF) in surgery. The aim of this study was to clarify if GF play a role in anterior cruciate ligament (ACL) surgery. Twenty patients with laxity caused by a torn ACL underwent arthroscopically assisted reconstruction with autologous hamstring tendons. We performed a prospective study with these patients randomized into 2 groups: GF-treated and control. Growth factors were obtained according to the GPS Biomet-Merck technique and are applied to femoral and tibial tunnels during surgical procedure. Patients were evaluated clinically and functionally. Computed tomography (CT) of the knee was performed in all the patients; a limited number of patients underwent magnetic resonance imaging (MRI). There were no significant differences concerning KOOS, IKDC, KT-1000, Tegner score rating and clinical examination between the two groups 6 months after ACL surgery. CT highlighted a significant difference (p<0.01) between ACL density of the two groups and showed that ACL density was similar to that of the posterior cruciate ligament in GF-treated group. In this group, however, one patient had a synovitic reaction: the new ACL was increased, hypertrophic and surrounded by a reaction of soft tissues. GF may accelerate the integration of the new ACL in the femoral and tibial tunnels, but further clinical studies are necessary to better understand the mechanism of action of GF, widely studied only in vitro and in animal models.     

胫骨-股骨单隧道双束解剖重建前交叉韧带

目的探讨胫骨-股骨单隧道双束重建前交叉韧带（ACL）的近期临床效果。方法对本组2009年4月至2011年4月收治的46例ACL损伤患者进行胫骨-股骨单隧道双束解剖重建ACL,先后钻取胫骨、股骨隧道,屈膝120。由前内侧入路建立股骨隧道,之后引入双束同种异体肌腱（或自体肌腱）,肌腱胫骨端、股骨端（沿肌腱间打入钉鞘形成双束）固定,术后随访,按照IKDC和Lysholm膝关节评分标准评价疗效。结果所有患者均获得1年以上随访。最后随访时,所有患者前抽屉试验阴性,45例患者（97．8％）Lachman试验阴性,1例患者Lachman试验I度阳性。KT-1000检查显示双侧膝关节前向松弛度差值平均为（-0．47±1．39）mm,手术前后有统计学差异（t=36．07,P〈0．01）;其中30例（65．2％）〈0mm,即患侧关节稳定度高于健侧;15例（32．6％）为0～2mm;1例（2．1％）〉2mm。所有患者轴移试验检查均为阴性。活动度检查发现42例伸屈活动度均正常,1例有5。屈膝欠缺,1例患者有10。屈膝欠缺,2例有5。过伸欠缺。从膝关节稳定性方面分析,45例（97．8％）IKDC评级为正常,1例（2．2％）评级为接近正常。综合分析,44例（95．7％）IKDC评级正常,2例（4．3％）为接近正常。术后IKDC膝关节主观评分为（94．9±3．7）分,Lysholm评分为（93．71±3．3）分。受伤前Tegner评分平均为7．3分,最后随访时为6．9分。结论对膝关节ACL断裂患者施行胫骨一股骨单隧道双束解剖重建,能够建立具有高度稳定性的膝关节,使所有患者获得IKDC评级正常或者接近正常的结果。     

Outcome of double bundle anterior cruciate ligament reconstruction using crosspin and aperture fixation

Background:

Double bundle anterior cruciate ligament (DBACL) reconstruction is said to reproduce the native anterior cruciate ligament (ACL) anatomy better than single bundle anterior cruciate ligament, whether it leads to better functional results is debatable. Different fixation methods have been used for DBACL reconstruction, the most common being aperture fixation on tibial side and cortical suspensory fixation on the femoral side. We present the results of DBACL reconstruction technique, wherein on the femoral side anteromedial (AM) bundle is fixed with a crosspin and aperture fixation was done for the posterolateral (PL) bundle.

Materials and Methods:

Out of 157 isolated ACL injury patients who underwent ACL reconstruction, 100 were included in the prospective study. Arthroscopic DBACL reconstruction was done using ipsilateral hamstring autograft. AM bundle was fixed using Transfix (Arthrex, Naples, FL, USA) on the femoral side and bio interference screw (Arthrex, Naples, FL, USA) on the tibial side. PL bundle was fixed on femoral as well as on tibial side with a biointerference screw. Patients were evaluated using KT-1000 arthrometer, Lysholm score, International Knee Documentation Committee (IKDC) Score and isokinetic muscle strength testing.

Methods:

Out of 157 isolated ACL injury patients who underwent ACL reconstruction, 100 were included in the prospective study. Arthroscopic DBACL reconstruction was done using ipsilateral hamstring autograft. AM bundle was fixed using Transfix (Arthrex, Naples, FL, USA) on the femoral side and bio interference screw (Arthrex, Naples, FL, USA) on the tibial side. PL bundle was fixed on femoral as well as on tibial side with a biointerference screw. Patients were evaluated using KT-1000 arthrometer, Lysholm score, International Knee Documentation Committee (IKDC) Score and isokinetic muscle strength testing.

Results:

The KT-1000 results were evaluated using paired t test with the P value set at 0.001. At the end of 1 year, the anteroposterior side to side translation difference (KT-1000 manual maximum) showed mean improvement from 5.1 mm ± 1.5 preoperatively to 1.6 mm ± 1.2 (P < 0.001) postoperatively. The Lysholm score too showed statistically significant (P < 0.001) improvement from 52.4 ± 15.2 (range: 32-76) preoperatively to a postoperative score of 89.1 ± 3.2 (range 67-100). According to the IKDC score 90% patients had normal results (Category A and B). The AM femoral tunnel initial posterior blow out was seen in 4 patients and confluence in the intraarticular part of the femoral tunnels was seen in 6 patients intraoperatively. The quadriceps strength on isokinetic testing had an average deficit of 10.3% while the hamstrings had a 5.2% deficit at the end of 1 year as compared with the normal side.

Conclusion:

Our study revealed that the DBACL reconstruction using crosspin fixation for AM bundle and aperture fixation for PL bundle on the femoral side resulted in significant improvement in KT 1000, Lysholm and IKDC scores.     

The incidence and significance of femoral tunnel widening after quadrupled hamstring anterior cruciate ligament reconstruction using femoral cross pin fixation

Purpose: The purpose of this study was to evaluate the amount of femoral tunnel widening that occurred after anterior cruciate ligament reconstruction using quadrupled hamstring autografts and to determine the clinical significance of any such tunnel enlargement. Type of Study: Retrospective clinical analysis. Methods: Twenty-nine patients who had undergone reconstruction of a torn anterior cruciate ligament with quadrupled hamstring autograft and cross pin femoral fixation were evaluated to determine the incidence and significance of postoperative femoral tunnel widening. A single surgeon performed all procedures, and average follow-up was 18.4 months (range, 12 to 31.5 months). All patients underwent flexion posteroanterior and lateral radiographs, an examination for determination of an International Knee Documentation Committee (IKDC) rating, had KT-1000 data collected, and completed Lysholm and Knee Outcome Survey functional questionnaires. Femoral tunnels were clearly seen in 27 patients. The tunnel diameters were measured at the opening of the tunnel, at the widest part of the tunnel, and just proximal to the cross pin. The amount of tunnel widening for each patient was then compared with the individual’s KT-1000 data, IKDC rating, and Lysholm and knee outcome survey scores to assess correlation. Results: Four different tunnel morphologies were noted, with the linear type being the most common. The widening at the greatest tunnel diameter was 65.5% on average. Side-to-side KT-1000 differences averaged 1.04 mm at 30 lb, and 1.10 mm at manual maximum. Eleven patients had IKDC overall ratings of normal, 13 had ratings that were nearly normal, and 2 had abnormal. Average Lysholm and knee outcome survey scores were 92.6 and 93.9, respectively. A significant correlation was found only between F2 and F3 widening with Lysholm scores. However, the significance was eliminated with removal of 2 outliers. Conclusions: The exact etiology of postoperative anterior cruciate ligament tunnel widening remains unknown. The present study reveals that significant tunnel widening occurs with quadrupled hamstring autografts and femoral cross pin fixation. However, the widening does not appear to have a significant effect on postoperative ligament laxity or functional knee scores, at least in the short term.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 19, No 5 (May-June), 2003: pp 470–476     

保留并牵张残留纤维的前十字韧带双束重建术

目的 评估在亚急性期进行保留并牵张残留纤维的前十字韧带双束重建的临床效果.方法 2006年1月至2006年6月,对56例前十字韧带损伤患者在亚急性期进行保留并牵张残留纤维的前十字韧带双束重建.前十字韧带双束重建采用四隧道八股肌腱移植的方法.使用PDS缝线穿缝胫骨侧残留纤维,经深束股骨隧道牵张固定.使用IKDC及Lysholm评分标准评估疗效.结果 53例随访2年以上.末次随访时所有患者Lachman试验均为阴性.屈膝25°KT-1000检测结果显示双侧膝关节松弛度差值为(-0.44±1.53)mm,与术前(8.01±1.83)mm比较差异有统计学意义(t=37.03,P=0.0001).29例(54.7%)双侧膝关节松弛度差值小于0mm,提示患膝相对于健侧更为稳定或紧张.24例(45.3%)双侧膝关节松弛度差值为0～2mm.所有患者轴移试验均阴性.48例膝关节活动度正常,2例有5°屈曲受限,1例有小于5°屈曲受限,2例有5°过伸受限.根据IKDC评估标准,51例(96.2%)正常,2例(3.8%)接近正常.IKDC主观评分为(95.6±3.1)分,Lysholm评分为(94.8±2.9)分.受伤前Tegner评分平均为7.3分,末次随访时为7.1分.结论 根据2年以上随访结果,以IKDC为评估标准,保留并牵张残留纤维的前十字韧带双束重建能够使96.2%的患者恢复正常,3.8%的患者接近正常.     

关节镜下保留残端五重折股薄肌腱重建前交叉韧带的疗效分析

目的 介绍一种单独应用股薄肌腱重建前交叉韧带(ACL)的方法,并评估其疗效.方法 2003年4月至2008年5月,前瞻性研究采用保留ACL胫骨侧残留部分单独应用股薄肌腱重建ACL的方法治疗40例ACL损伤患者,其中男22例,女18例;年龄17～43岁,平均30.7岁.急性损伤33例,陈旧性损伤7例.受伤至手术时间平均3.4周(1～12周).术中评价所取股簿肌腱的长度,移植腱的长度及直径.术后评价包括KT-2000的前方不稳定性患健差,膝关节活动度,屈膝肌力的患健差,手术前后的IKDC评分及VAS评分.结果 所取股薄肌腱的长度平均为239 mm;移植腱直径为7.6 mm,长度为41.4 mm.KT-2000的前方不稳定性患健差术前平均为5 mm,术后平均为1 mm,差异有统计学意义(P＜0.05).膝关节活动度与健侧最大相差不到5°,差异无统计学意义(P＞0.05).术后6个月患膝在60°/s伸膝时扭矩恢复到健侧的89%,术后1年恢复到92%,术后2年恢复剑95%;术后6个月患膝在90°/s屈膝时扭矩恢复到健侧的85%,术后1年恢复到86%,术后2年恢复到89%.术前IKDC评分平均为49.3分,术后2年平均为95.0分;VAS评分术前平均为30.3分,术后2年平均为85.4分,差异均有统计学意义(P＜0.05).结论 单独廊用股薄肌腱重建ACL,屈膝肌力恢复满意.保留残留韧带可促进重建韧带的血运和本体感觉的恢复,加速患者的康复.     

Radiological landmarks for placement of the tunnels in single-bundle reconstruction of the anterior cruciate ligament

There is little evidence examining the relationship between anatomical landmarks, radiological placement of the tunnels and long-term clinical outcomes following anterior cruciate ligament (ACL) reconstruction. The aim of this study was to investigate the reproducibility of intra-operative landmarks for placement of the tunnels in single-bundle reconstruction of the ACL using four-strand hamstring tendon autografts. Isolated reconstruction of the ACL was performed in 200 patients, who were followed prospectively for seven years with use of the International Knee Documentation Committee forms and radiographs. Taking 0% as the anterior and 100% as the posterior extent, the femoral tunnel was a mean of 86% (sd 5) along Blumensaat's line and the tibial tunnel was 48% (sd 5) along the tibial plateau. Taking 0% as the medial and 100% as the lateral extent, the tibial tunnel was 46% (sd 3) across the tibial plateau and the mean inclination of the graft in the coronal plane was 19 degrees (sd 5.5). The use of intra-operative landmarks resulted in reproducible placement of the tunnels and an excellent clinical outcome seven years after operation. Vertical inclination was associated with increased rotational instability and degenerative radiological changes, while rupture of the graft was associated with posterior placement of the tibial tunnel. If the osseous tunnels are correctly placed, single-bundle reconstruction of the ACL adequately controls both anteroposterior and rotational instability.     

Accuracy in tunnel placement for ACL reconstruction. Comparison of traditional arthroscopic and computer-assisted navigation techniques.

The purpose of this randomized, prospective study was to compare accuracy in tunnel placement as performed with a traditional arthroscopic anterior cruciate ligament (ACL) reconstruction technique and with KneeNavTM ACL, a computer-assisted surgical navigation technique. Two surgeons experienced in ACL reconstruction, but inexperienced in computer-assisted surgical navigation technique, each randomly used traditional arthroscopic guides or KneeNavTM ACL to drill a tunnel in twenty identical foam knees. Placement of the resulting tibial and femoral tunnels was measured with a computer-assisted digitizing method and compared to traditional biplanar radiographs. Statistical analysis with Student's t-test was used to compare the distance from the ideal tunnel placement to the femoral and tibial tunnels. Accuracy of tunnel placement with KneeNavTM ACL was significantly better than that obtained with the traditional arthroscopic technique. Distances from the ideal tunnel placement to the femoral and tibial tunnels were 4.2 +/- 1.8 mm (mean +/- SD) and 4.9 +/- 2.3 mm, respectively, for the traditional arthroscopic technique, and 2.7 +/- 1.9 mm (femur) and 3.4 +/- 2.3 mm (tibia) for KneeNavTM ACL. These differences were statistically different. Tunnel placement for ACL reconstruction with KneeNavTM ACL, an image-based, computer-assisted surgical navigation device with a simple and intuitive interface, was more accurate than with the traditional arthroscopic technique.     

Double bundle revision of a malplaced single bundle vertical ACL reconstruction: ACL revision surgery using a two femoral tunnel technique

Background  Several factors influence the outcome after ACL reconstruction. One of the most important factors influencing the resulting knee kinematics and subjective instability is femoral tunnel placement. Revision can be necessary if the femoral tunnel is drilled transtibial in the roof of femoral notch (mismatch). Hypothesis  Double bundle reconstruction using two femoral tunnels and one tibial tunnel technique can be used in revision of a primary vertical ACL reconstruction. Study design  Case series (level of evidence III). Methods  ACL revision was performed in five patients complaining instability after primary transtibial ACL reconstruction. Clinical examination, X-ray and CT analysis were performed to evaluate objective knee laxity, tunnel placement and widening. In all patients a technique using two femoral tunnels in a two medial portal technique and one tibial tunnel was used. Patients were reevaluated at a follow up of 24 months. Results  Preoperatively, pivot shift tests were 2+ in three and 1+ in the remaining two patients. Lachman test was found to be positive in all patients (4 patients, 2+ firm endpoint; 1 patient, 2+ soft endpoint). X-rays showed a femoral tunnel position at 11.30 (1 patient) and 12.00 o’clock (4 patients). In one patient significant tibial tunnel enlargement was to be found. At a follow up of 24 months, KT 1000 was <2 mm side to side difference and the pivot shift test was negative in all patients. Conclusion  Revision of a primary vertical ACL reconstruction can be safely performed using a double bundle reconstruction with two femoral tunnels in a two medial portal technique and one tibial tunnel technique. The femoral tunnel need to be located in the anatomic origin of the AM and PL bundle. Clinical relevance  Femoral tunnel placement in the notch of the intercondylar notch should be avoided. In these cases without significant tunnel enlargement, a primary double bundle revision with two femoral and one tibial tunnel can be performed.     

前交叉韧带单束重建中股骨椭圆隧道技术与圆隧道技术的比较研究

目的通过与传统圆隧道技术相比,探讨前交叉韧带(anterior cruciate ligament,ACL)单束重建中采用椭圆隧道技术制备股骨隧道的疗效及优势。方法回顾分析2016年3月-2018年2月125例采用自体肌腱单束解剖重建ACL且符合选择标准的患者临床资料,其中43例术中采用椭圆隧道技术制备股骨隧道(A组),82例采用圆隧道技术(B组)。两组患者年龄、性别、体质量指数、病程、损伤侧别、损伤原因以及术前Lysholm评分、国际膝关节文献委员会(IKDC)评分、Tegner评分、KT-1000测量值等一般资料比较,差异均无统计学意义(P>0.05)。记录两组患者术后3、6、12、24个月Lysholm评分、IKDC评分和Tegner评分,采用KT-1000评价关节稳定性。术后1d三维CT评估股骨和胫骨隧道位置。术后6、12、24个月MRI检查,测量ACL移植物近、中、远端信号/噪声比(signal/noise quotient,SNQ)。对行二次关节镜检查患者评价移植物完整性、滑膜覆盖以及张力情况。结果两组患者均获随访,随访时间12~26个月,平均23个月。A组2例、B组5例发生切口红肿,B组1例发生胫骨隧道裂纹骨折,A组1例发生膝关节屈曲活动度受限。除术后3个月Tegner评分外,其余各时间点A组Lysholm、IKDC、Tegner评分均明显高于B组(P<0.05)。术后各时间点A组KT-1000测量值亦明显小于B组(P<0.05)。术后1 d三维CT检查示两组股骨及胫骨隧道均位于ACL止点印迹内。MRI复查两组均无移植物断裂及明显松弛发生。术后6个月两组移植物中、远端SNQ差异无统计学意义(P>0.05),近端A组明显低于B组(P<0.05);术后12、24个月A组移植物近、中、远端SNQ均低于B组(P<0.05)。A组21例及B组38例患者进行二次关节镜检查,两组移植物完整性、滑膜覆盖及张力比较,差异均无统计学意义(P>0.05)。结论与传统圆隧道技术相比,ACL单束重建术中采用椭圆隧道技术制备股骨隧道,术后移植物成熟度更好,患者能获得更好膝关节功能。     

X线影像导航系统辅助关节镜下前交叉韧带重建术

目的 探讨X线影像导航系统辅助关节镜下前交叉韧带重建手术的可行性和隧道位置的精确性。方法 2005年12月至2006年2月共行X线影像导航系统辅助前交叉韧带重建手术30例（导航手术组）,同期使用传统关节镜手术技术重建前交叉韧带40例（传统手术组）,术前进行股骨、胫骨隧道理想位置的设计。术中C臂透视机获得正侧位影像后传输入计算机系统形成虚拟工作界面。膝关节周围分别固定股骨、胫骨追踪器。手术工具装配追踪器。经过注册及校准后,导航系统通过捕获追踪器发射的信号实时跟踪手术工具的位置方向,并叠加在工作界面上,达到导航的目的。本文对导航手术组进行总结,术后进行胫骨隧道位置测量,并与传统手术组进行比较。结果术后测量,导航手术组胫骨隧道位置平均值45．90％（41．00％～49．80％,标准差2．36％）,传统手术组胫骨隧道位置在41．05％（范围25．00％～54．00％,标准差6．01％）,两组结果差异有统计学意义（P〈0．05）。同时导航组的平均手术时间较传统组延长20min,透视次数为4次。术后短期随访（1-3个月）,两组膝关节稳定性无明显差异。结论 X线影像导航系统辅助关节镜下前交叉韧带重建手术是安全、可行的,通过术前规划,可以使股骨、胫骨隧道位置更精确。     

Blood loss in anterior cruciate ligament (ACL) reconstruction with and without intercondylar notchplasty: does it affect the clinical outcome?

Blood loss is associated with any surgical procedure and should be reduced wherever possible. It was our impression that notchplasty adds to the amount of postoperative bleeding after anterior cruciate ligament (ACL) reconstruction. With posterior placement of the tibial tunnel, notchplasty is optional in many cases. This study aimed to quantify blood loss with and without notchplasty after arthroscopically assisted ACL reconstruction using bone-patellar tendon-bone autografts. We performed a prospective clinical study of 58 patients, who had undergone arthroscopically assisted autogenous patellar tendon ACL reconstruction. In group I, a notchplasty was necessary according to the local anatomical criteria (intraoperative impingement test). In group II, ACL replacement could be performed without notchplasty. Single and total day drainage volume, serum and suction drain hemoglobin (Hb) and hematocrit (Hct) levels were monitored. One year after surgery, the patients were reviewed to assess the outcome according to the IKDC and Lysholm scores and the KT-1000 arthrometer. The total drainage volume was 448 ml (range 150–550 ml) in group I and 299 ml (range 50–420 ml) in group II (p < 0.001). The serum hematocrit (Hct) decrease was 9.7% in group I and 7.4% in group II (p < 0.001). At 12 months after surgery, the IKDC and Lysholm score evaluations and the KT-1000 arthrometer measurements revealed no clinical differences between the notchplasty and non-notchplasty groups. Despite a 30% increase in blood loss, notchplasty has been shown to be a useful procedure to prevent graft impingement without negative side-effects. Received: 7 December 2000     

Early tunnel enlargement after arthroscopic ACL reconstructions

The aim of this study was to evaluate the tunnel enlargement phenomenon after ACL reconstructions performed with hamstrings tendons fixed using the cross pin technique. Sixty-two knees in 62 patients were followed for two years to evaluate the possible clinical implications of the femoral and tibial tunnel enlargements noted after ACL reconstruction. The reconstructions were done with hamstring tendons using the cross-pin technique. Evaluation was based on calculated clinical scores (IKDC and Lysholm knee scores) and quantified by KT-1000 measurements. Sagittal and coronal plane computed tomography and conventional radiography were performed 3 days after operation and were repeated after 3 and 6 weeks, 6, 12 and 24 months, to assess early tunnel enlargement. Although it seems that tunnel enlargement after ACL reconstruction has no impact on the clinical results, long-term implications and potential need for revision surgery must be assessed. In this study, tunnel enlargement was noted fairly early after operation and was thought to be related with drilling of the tunnels. A possible solution to this problem may be drilling the tunnels to a diameter 1 mm smaller than the measured graft diameter, then to enlarge the tunnels to the graft diameter with the appropriate tunnel dilator.     

Bioabsorbable polyglyconate interference screw fixation in anterior cruciate ligament reconstruction: a prospective computed tomography-controlled study.

PURPOSE: It was the purpose of the study to evaluate a new polyglyconate bioabsorbable interference screw for graft fixation in anterior cruciate ligament (ACL) reconstruction. TYPE OF STUDY: Prospective randomized. MATERIALS AND METHODS: Forty patients who underwent endoscopic ACL reconstruction were included in the study and randomized intraoperatively. Group A consisted of 20 patients (6 women, 14 men; mean age, 29.6 years) who had femoral bone block fixation with a bioabsorbable interference screw and tibial fixation with a titanium interference screw. Group B included 20 patients (5 women, 15 men; mean age 29.6 years) who had fixation of both femoral and tibial bone blocks with titanium interference screws. There was no significant difference between the groups with regard to age, gender, height, weight, time from injury to surgery, activity level, and concomitant injuries. RESULTS: Clinical results (using IKDC, Lysholm, Tegner scores) of the 2 groups as well as instrumented laxity measurements (KT-1000) did not show significant (P >.05) differences at any stage of follow-up. No complications with respect to graft fixation could be found. Computed tomography scans, performed within the first postoperative week, at 6 weeks, and at 3, 6, 12, and 24 months postoperatively revealed a uniform picture for all patients within the groups, showing completed screw degradation at 12 months in group A. CONCLUSION: Polyglyconate interference screw fixation for patellar tendon grafts has not been found to be associated with increased clinical complications or significant osteolysis. It provided equivalent fixation and clinical results compared with titanium screws. However, replacement of the screw with bone did not take place for up to 3 years postoperatively.     

Editorial Commentary: Anteromedial Portal Drilling of the ACL Femoral Socket Avoids Transtibial Constraint Results in Anatomic Reconstruction and Superior Outcomes

Femoral and tibial tunnel locations for ACL grafts should be predicated on anatomy. Regarding femoral ACL socket or tunnel creation, multiple techniques have been debated. Network meta-analysis shows that the anteromedial portal (AMP) technique results in better anteroposterior and rotational stability than does the “standard” constrained, transtibial technique based on side-to-side differences in laxity and pivot-shift tests, as well as IKDC objective scores. The AMP provides a direct shot at the anatomic ACL origin on the femur. It avoids the osseous constraint of the reamer that hampers transtibial approaches. It avoids the extra incision required by the outside-in technique and the accompanying graft obliquity. Despite the need for knee hyperflexion and the potential for shorter femoral sockets, the AMP technique should be easily reproducible for an accomplished ACL surgeon to reproduce the patient’s anatomy.     

Comparing 2-year outcomes of anterior cruciate ligament reconstruction using either patella-tendon or semitendinosus-tendon autografts: a non-randomised prospective study

PURPOSE: To compare the results of anterior cruciate ligament (ACL) reconstructions using either a patella-tendon autograft or a semitendinosus-tendon autograft. METHODS: Based on surgeon experience and preference, 68 patients underwent ACL reconstruction using either a quadruple-strand semitendinosus autograft (n = 34) or a central one-third bone-patella tendon-bone autograft (n = 34). Each patient was assessed preoperatively and postoperatively at 3, 6, and 24 months using the International Knee Documentation Committee (IKDC) knee score, Biodex muscle strength and endurance testing, and the KT1000 instrumented arthrometer test of knee laxity to anterior translation. All assessments at the 2-year follow-up were performed by the same physician and physiotherapist. RESULTS: While ACL reconstruction improved knee stability and IKDC knee scores significantly, there was no statistically significant difference between semitendinosus- and patella-tendon autograft reconstructions in terms of long-term knee score or laxity to anterior translation. Semitendinosus graft reconstruction was associated with less donor-site morbidity and hamstring weakness. Meniscectomy was associated with poorer long-term knee scores. CONCLUSION: ACL reconstruction is associated with a significantly better IKDC knee score and laxity measurement at 2-year follow-up. However, we were unable to demonstrate a significantly better long-term outcome in knee score or laxity to anterior translation with either a patella-tendon autograft or a semitendinosus-tendon autograft.     

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.     

Anterior cruciate ligament tunnel placement: Comparison of insertion site anatomy with the guidelines of a computer-assisted surgical system

Purpose: With the development of computer-assisted surgery (CAS) systems, the surgeon’s ability to operate a CAS planning station will become essential. For example, default parameters in computed tomographic (CT) data are being used to place tunnels in anterior cruciate ligament (ACL) reconstruction. The goal of this study was to compare the location of the insertion sites in ACL reconstruction anatomically, via roentgenographic images and via CT scan data and to validate these tunnel placement parameters. Type of Study: Cadaveric analysis. Methods: Eight human cadaveric knees were marked with 6 copper wires 1 mm in diameter around the circumference of the insertions of the ACL. Using lateral roentgenograms and CT scans that were subsequently transferred to the CAS planning station, the tunnel locations were determined. These were based on a distance from the back of the condyle (location A) and from the roof of the notch (location B) on the femur and on a distance posterior from the tuberosity to the posterior margin along the tibial plateau, which is set as the CAS planning station’s default. Locations according to roentgenograms and CT scans were then compared and the accuracy of the CAS planning station was assessed. Results: Comparison of roentgenograms and CT revealed a femoral insertion at 27.5% ± 3.2% and 26.9% ± 3.5% (roentgenograms) and 26.6% ± 1.9% and 26.3% ± 2.4% (CT), respectively. The CAS planning station provided a tunnel location that was 1.3 ± 1.0 mm (0.3 to 2.5 mm) away from the actual femoral ACL insertion. The tibial tunnel was placed according to the copper wire markers and was found to be at 46.2% ± 2.8% (roentgenograms) and 45.4% ± 2.1% (CT). No statistical differences between position in CT and roentgenograms could be detected (P > .05). Conclusions: The compared methodologies showed similar locations of the ACL insertions, assuring accurate preoperative planning with the CAS system. However, the CAS system requires adjustment to each individual knee anatomy.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 19, No 2 (February), 2003: pp 154–160     

Bone tunnel enlargement after ACL reconstruction using autologous hamstring tendons: a CT study

Purpose: To evaluate prospectively the increase in the size of the tibial and femoral bone tunnel following arthroscopic anterior cruciate ligament (ACL) reconstruction with quadrupled-hamstring autograft. Methods: Twenty-five consecutive patients underwent arthroscopic ACL reconstruction with quadrupled-hamstring autograft. Preoperative clinical evaluation was performed using the Lysholm knee score, Tegner activity level, and International Knee Documentation Committee forms and a KT-1000 arthrometer (side to side). Computed tomography (CT) of the femoral and tibial tunnel was performed on the day after operation in all cases and at mean follow-up of 10 months (range 9–11 months).Results: All of the clinical evaluation scales performed showed an overall improvement. The postoperative anterior laxity difference was <3 mm in 16 patients (70%) and 3–5 mm in seven patients (30%). The mean average femoral tunnel diameter increased significantly (3%) from 9.04±0.05 mm postoperatively to 9.3±0.8 mm at 10 months; tibial tunnel increased significantly (11%) from 9.03±0.04 mm to 10±0.8 mm. There were no statistically significant differences between tunnel enlargement, clinical results, and arthrometer evaluation. Conclusions: The rate of tunnel widening observed in this study seems to be lower than that reported in previous studies that used different techniques. We conclude that an anatomical surgical technique and a less aggressive rehabilitation process influenced the amount of tunnel enlargement after ACL reconstruction with doubled hamstrings.

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Résumé But: évaluer prospectivement l’augmentation de taille des tunnels osseux après reconstruction arthroscopique du LCA par les ischio-jambiers. Méthode: 25 patients avaient été opérés. L’évaluation pré-opératoire avait été faite avec le score de Lysholm, les critères IKDC et de niveau d’activité Tegner et la mesure bilatérale avec l’arthromètre KT-1000. Un scanner des tunnels était réalisé dans tous les cas le jour suivant la chirurgie et à un suivi moyen de 10 mois (9–11). Résultats: Tous les scores cliniques montraint une amélioration globale. La différence de laxité antérieure après l’intervention était de moins de 3mm pour 16 patients (70%) et de 3 à 5 mm pour 7 (30%). Le diamètre moyen du tunnel fémoral augmentait significativement (3%) de 9,04±0,05 mm en post-opératoire à 9,3±0,8 mm à 10 mois ; le tunnel tibial augmentait (11%) de 9,03±0,004 à 10±0,8 mm. Il n’y avait pas de corrélation significative entre l’élargissement des tunnels, les résultats cliniques et les mesures à l’arthromètre. Conclusions: La proportion d’élargissement des tunnels observée dans cette étude semble plus faible rapportées avec des techniques différentes. Nous pensons qu’une technique très anatomique et une rééducation peu agressive influence l’élargissement des tunnels dans la reconstruction du LCA par les ischio-jambiers.