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。     

Tunnel enlargement 5 years after anterior cruciate ligament reconstruction: a radiographic and functional evaluation

Purpose

The aetiology and clinical significance of enlargement of bone tunnels following anterior cruciate ligament (ACL) reconstruction remains controversial. This phenomenon has been attributed to biological factors and mechanical factors. We wanted to study the amount of femoral and tibial tunnel enlargement 5 years post-ACL reconstruction. By standardizing the type of femoral fixation, we also wanted to determine whether the type of tibial fixation had any bearing to the amount of tibial tunnel enlargement.

Methods

All patients who underwent arthroscopic hamstring autograft ACL reconstruction between January 2000 and December 2000 were identified. All grafts were fixed with close-looped endobutton proximally. The grafts were fixed on the tibial side with staples or bioabsorbable interference screws. At a minimum of 5 years after surgery, these patients were recalled. They were assessed with Lysholm knee, Tegner activity and the IKDC Subjective and Objective forms and a KT-1000 arthrometer. The diameter of the bone tunnels and tunnel positions in the anterior–posterior and lateral radiographs were measured using digital callipers by a two blinded researchers.

Results

We found that the femoral tunnel enlarged more than the tibial tunnel. At 5 years, the mean tibial tunnel enlargement was 2.46 mm and the mean femoral tunnel enlargement was 3.23 mm. All 54 patients had endobutton femoral fixation. Of them, 34 patients had tibial graft fixation with staples (extracortical fixation) and 20 patients had tibial graft fixation with bioabsorbable interference screws (aperture fixation). The mean enlargement as measured by the two independent observers in the extracortical group was 1.98 mm (24.7 %)* and 1.51 mm (18.2 %)**compared to 3.27 mm (40.4 %)* and 2.92 mm (30.0 %)** in the aperture fixation group. This difference in tibial tunnel enlargement between the groups was significant (p < 0.001, mean difference 1.29 mm). However, this was not correlated with any significant difference in clinical outcome at 5 years.

Conclusion

We, like some authors, have shown that the use of interference screws in tibial fixation despite being aperture fixation actually has a greater amount of tibial enlargement. This lends weight to the biological theory to tunnel enlargement.     

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.     

Comparative study of knee anterior cruciate ligament reconstruction with or without fluoroscopic assistance: a prospective study of 73 cases

INTRODUCTION: Correct placement of both tibial and femoral tunnels is one of the main factors for a favorable clinical outcome after anterior cruciate ligament (ACL) reconstruction. We used an original system of computer assisted surgery (CAS). The system, based on fluoroscopic guidance combined with special graphical software of image analyzing, showed to the surgeon, before drilling, the recommended placement of tibial and femoral tunnel centers. We compared the first anatomical and clinical results of this procedure to the usual one single incision technique. MATERIALS AND METHODS: We conducted a prospective study on 73 patients; 37 patients were operated on with CAS and 36 without CAS, by the same senior surgeon. The mean age was 27 years for both groups. Every patient was reviewed at an average of 2.2 years (range 1-4.5) by an independent observer, using IKDC scoring system, KT-1000, and passive stress radiographs. RESULTS: Time between ACL rupture and reconstruction averaged 30 months for both groups. CAS needed 9.3 min extra surgery time. Clinical evaluation was graded from A to C as per the IKDC scoring system: 67.6% A, 29.7% B, 2.7% C with CAS; and 60% A, 37.1% B, 2.9% C without CAS. IKDC subjective knee evaluation score averaged 89.7 with CAS and 89.5 without CAS. Pre operative KT-1000 maxi manual differential laxity averaged 7. At revision time, all the patients after CAS had a differential laxity less than 2 and 97.7% without CAS. Stress X-rays differential laxity averaged 2.4 mm with CAS and 3 mm without CAS. The area of dispersion of the tunnels' center was smaller on the femoral side using the CAS method. There was no statistically significant difference between both groups using IKDC score, KT-1000 and passive stress radiographs. CONCLUSIONS: The CAS method provided a more accurate and reproducible tunnels placement without clinical significant effect.     

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: a 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of < or =5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was < or =1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.     

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: A 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of ≤5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was ≤1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.     

Posterior wall blowout on computed tomography after anterior cruciate ligament reconstruction

BackgroundDuring anterior cruciate ligament (ACL) reconstruction, even when a posterior wall of the femoral bone tunnel is identified, computed tomography (CT) occasionally demonstrates a breach of the posterior femoral cortex of the femoral bone tunnel, i.e., posterior wall blowout, after ACL reconstruction (posterior wall blowout-like phenomenon). This study aimed to investigate the influence of the posterior wall blowout-like phenomenon on clinical outcomes after ACL reconstruction using hamstring tendon.MethodsA total of 105 patients who underwent CT examination two weeks after ACL reconstruction were enrolled. A cortical suspension device was used for femoral side fixation in all cases. Posterior wall was identified in all cases during the surgery. The side-to-side difference in anterior knee laxity, pivot shift test, Lysholm knee score, the International Knee Documentation Committee (IKDC) subjective form, and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were evaluated one year after the surgery. A second CT examination was performed 6–12 months after the surgery, if a posterior wall blowout-like phenomenon was identified in the first CT examination.ResultsTwo weeks after the surgery, 16 of the 105 patients showed a posterior wall blowout-like phenomenon. Twelve of the 16 cases demonstrated a regenerated posterior femoral cortex of the femoral bone tunnel on their second CT images. There were no significant differences between the posterior wall blowout-like phenomenon group and the normal posterior wall group in terms of a side-to-side difference in anterior knee laxity (0.4 ± 1.5 mm and 0.1 ± 1.6 mm, respectively), pivot shift test, Lysholm knee score, IKDC score, and KOOS at one year after surgery. The length and diameter of the femoral bone tunnel were not significantly different between the two groups.ConclusionsPosterior wall blowout-like phenomenon after ACL reconstruction using a cortical suspension device did not negatively influence clinical outcomes.Level of evidenceIII – retrospective comparative clinical study.     

Effect of compaction drilling during ACL reconstruction with hamstrings on postoperative tunnel widening

Type of study This study investigates whether the amount of tibial and femoral bone tunnel enlargement following anterior cruciate ligament (ACL) reconstruction with hamstrings can be reduced by compaction bone tunnel drilling. Methods Patients undergoing primary ACL reconstruction with four-strand hamstrings (n = 26) were matched to either extraction drilling (n = 13) or compaction drilling (n = 13). Extracortical femoral fixation was by means of a 20 mm Endobutton CL and tibial fixation was by resorbable interference screw. A CT scan was performed on the second postoperative day and an average of 4 months (range 3.8–5 months) postoperatively in all patients. Tunnel enlargement was determined by digitally measuring the widths perpendicular to the long axis of the tunnels on an oblique coronal and axial plane. The CT measurements were compared to the intraoperative drill diameter. Results With extraction drilling the average tibial tunnel diameter proximal to the interference screw increased from 8.5 to 10.4 mm (P < 0.0001) and the average femoral tunnel from 8.0 to 10.6 mm (P < 0.0001). With compaction drilling it increased from 8.2 to 10.0 mm (P < 0.0001) and from 7.6 to 9.7 mm (P < 0.002), respectively. Tunnel widening was 22% on the tibial side for both groups and 33 versus 28% on the femoral side (P = 0.09) for extraction versus compaction drilling. Conclusion There was a significant tibial and femoral tunnel widening on CT an average of only 4 months following ACL reconstruction with hamstrings. Compaction drilling with a stepped router did not prove to reduce the postoperative tunnel widening significantly. Tunnel widening was higher on the femoral side which could be related to the extracortical femoral fixation technique. Level of evidence Level 4. No benefits in any form have been received, or will be received, from a commercial party related directly or indirectly to the subject of this article.     

Tripled semitendinosus anterior cruciate ligament reconstruction with Endobutton fixation: A 2-3-year follow-up study of 35 patients

We evaluated the clinical outcome of tripled semitendinosus tendon ACL reconstruction with femoral Endobutton (Acufex, Smith&Nephew, Andover, MA) and tibial Suture Washer (Acufex, Smith&Nephew, Andover, MA) (n 29) or post screw fixation (n 6) in 35 patients on an average of 28 (20-37) months after surgery. On the basis of IKDC criteria, 22 patients showed a normal or nearly normal knee function and 25 patients had a KT 1000 maximal manual side-to-side difference of &#104 5 mm at follow-up. Subjectively, 28 patients graded their knee function as normal or nearly normal. The average Lysholm score was 88 points, average OAK score 90 points and average modified HSS score 93 points. 19 patients reached their preinjury level of activity at follow-up. The postoperative Lachman test was &#104 1+ in 24 patients and 24 patients also showed an absent pivot shift. Significant bone tunnel enlargement occurred in 26 patients on the femoral side and in 23 patients on the tibial side. We found no correlation between bone tunnel enlargement and clinical outcome. The clinical outcome of tripled semitendinosus tendon ACL reconstruction with Endobutton fixation on the femoral side was not entirely satisfactory. The procedure was associated with a high incidence of bone tunnel enlargement in this series.     

前交叉韧带重建术后骨道增宽的临床研究

目的分析前交叉韧带（ACL）重建术后骨道增宽的发生率、增宽程度、骨道形状、相关因素及其与临床效果的关系。方法回顾性研究应用胭绳肌腱重建ACL手术后骨道的变化,通过X线片测量ACL重建术后的骨道直径。对51例患者行ACL重建手术,其中男性30例,女性21例。所有患者均获随访,平均随访时间16个月。主要研究及观察指标：患者性别、年龄、身高等因素,移植物的固定方式,随访时的关节活动度、膝关节稳定性检查（KT2000）及肌力恢复情况,以及股骨和胫骨的骨道直径、骨道位置和角度等。数据分析采用统计学卡方检验及相关性分析。结果前交叉韧带重建术后的骨道增宽率股骨85％-94％,胫骨65％;增宽程度股骨51％-53％,胫骨40％～44％。胫骨骨道增宽的形态以O型（冠位片）及V型（矢位片）最常见。骨道增宽与年龄、身高及体重指数相关。股骨骨道位置偏前会引起股骨骨道的增宽,股骨骨道角或胫骨骨道角越小,则股骨骨道越容易增宽。结论以腘绳肌腱为移植物重建前交叉韧带手术,术后骨道增宽的发生率与程度,股骨骨道较胫骨骨道明显。骨道增宽与患者年龄、身高以及骨道定位相关,其中股骨和胫骨骨道的位置及角度是引起术后骨道增宽的主要因素之一。骨道增宽与KT2000结果和术后肌力恢复情况相关。     

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.     

Anterior cruciate ligament (ACL) reconstruction with quadriceps tendon autograft and press-fit fixation using an anteromedial portal technique

ABSTRACT: BACKGROUND: This article describes an arthroscopic anterior cruciate ligament (ACL) reconstruction technique with a quadriceps tendon autograft using an anteromedial portal technique. METHODS: A 5 cm quadriceps tendon graft is harvested with an adjacent 2 cm bone block. The femoral tunnel is created through a low anteromedial portal in its anatomical position. The tibial tunnel is created with a hollow burr, thus acquiring a free cylindrical bone block. The graft is then passed through the tibial tunnel and the bone block, customized at its tip, is tapped into the femoral tunnel through the anteromedial portal to provide press-fit fixation. The graft is tensioned distally and sutures are tied over a bone bridge at the distal end of the tibial tunnel. From the cylindrical bone block harvested from the tibia the proximal end is customized and gently tapped next to the graft tissue into the tibial tunnel to assure press fitting of the graft in the tibial tunnel. The distal part of the tibial tunnel is filled up with the remaining bone.All patients were observed in a prospective fashion with subjective and objective evaluation after 6 weeks, 6 and 12 months. RESULTS: Thirty patients have been evaluated at a 12 months follow-up. The technique achieved in 96.7% normal or nearly normal results for the objective IKDC. The mean subjective IKDC score was 86.1 [PLUS-MINUS SIGN] 15.8. In 96.7% the Tegner score was the same as before injury or decreased one category. A negative or 1+ Lachman test was achieved in all cases. Pivot-shift test was negative or (+) glide in 86.7%. The mean side-to-side difference elevated by instrumental laxity measurement was 1.6 [PLUS-MINUS SIGN] 1.1 mm. Full ROM has been achieved in 92.3%. The mean single one-leg-hop index was 91.9 [PLUS-MINUS SIGN] 8.0 at the follow-up. CONCLUSIONS: Potential advantages include minimum bone loss specifically on the femoral side and graft fixation without implants.     

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.

     

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.     

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.     

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.     

Double-bundle anterior cruciate ligament reconstruction with split Achilles allograft and single tibia tunnel for small ACL tibial footprint : technical note with clinical results

Purpose

We describe a surgical technique of double-bundle ACL reconstruction with a single tibia tunnel and report the clinical outcome.

Methods

The Achilles tendon portion was split longitudinally into two separate bundles, namely, an anteromedial (AM) bundle with 7–8 mm diameter and a posterolateral (PL) bundle with 4–6 mm diameter. The central portion of the calcaneal bone plug was prepared with a diameter of 10 mm and a length of 30 mm. For the femoral tunnel preparation, we preferred inside out target through an accessory anteromedial portal for an approach to native ACL footprint and outside in reaming through separate incision on the lateral aspect of distal thigh to prevent cartilage injury of medial femoral condyle. 10 mm diameter of single tibia tunnel was prepared at the central portion of ACL tibial footprint. After graft passage from tibia to femoral side, fixation of calcaneal bone plug within the tibia tunnel was performed using two bioabsorbable cross pins. Then, AM bundle was first fixed at 45° of flexion while the PL bundle was fixed at 10° of flexion using bioabsorbable interference screws and augmented staples. Clinical results of 22 patients (18 males and 4 females, average age 30.7 years) who underwent double-bundle anterior cruciate ligament (ACL) reconstruction with this technique were evaluated.

Results

At an average follow-up of 30 months, there was significant improvement of the Lysholm knee score, the 2,000 IKDC subjective knee score, the median Tegner activity score and the side-to-side difference. According to the 2,000 IKDC knee examination form, the grade rated as normal in seven patients, nearly normal in 14 patients and abnormal in one patient at the latest follow-up. There were no postoperative complications and revisional surgeries.

Conclusions

Split Achilles allograft and single tibia tunnel technique for double-bundle ACL reconstruction can be an alternative option for patients with small tibial insertion sites.

Level of evidence

Level IV, therapeutic study.     

Editorial Commentary: It is Never Wrong to Perform Anterior Cruciate Ligament Revision Reconstruction as a Two-Stage Procedure

Revision anterior cruciate ligament (ACL) reconstruction can be performed in a single surgery, but in some instances, it requires 2 stages to get it right. The most common reasons for staged reconstruction include dilated bone tunnels on the tibial or femoral side (>13 mm), imperfectly placed bone tunnels that cannot be reused but cannot be avoided, and/or the need to combine the revision ACL reconstruction with meniscus and/or cartilage allograft transplantation. In my practice, we use prefabricated bone dowels, sizing up 0.5 to 1 mm relative to the size of the tunnel (after debridement) for both the femoral side and tibial side. The benefits are efficiency and reproducibility, while the challenges include cost and the potential need for multiple dowels if the prefabricated dowels are not long enough. We will occasionally add demineralized bone matrix, particularly on the tibial side, in the event that there is <5 mm of unfilled tunnel using the bone dowel. We wait ∼3 months before proceeding to the second stage using only plain radiographs to assess healing (advanced imaging such as computed tomography scan is not routinely used). We have also begun to push the limits of single-stage revision reconstruction, using dowels in a single setting. No matter what, it is never wrong to perform ACL revision reconstruction as a 2-stage procedure. When performed for the appropriate indications, outcomes tend to be good, regardless of the chosen technique.     

Influence of the postoperative activity level on tibial bone tunnel enlargement and functional treatment results following anterior cruciate ligament reconstruction using a patellar tendon autograft

AIM: This study was performed to evaluate the influence of the postoperative activity level on tibial bone tunnel enlargement following anterior cruciate ligament reconstruction using a mid-third patellar tendon autograft. METHODS: A clinical and radiological assessment was performed on 50 patients (21 male, 29 female, mean age 32 years, range 18 to 57 years) following ACL reconstruction using a patellar tendon autograft. The average follow-up examination was performed 18 (12 to 30) months after the operation. RESULTS: 33 patients (66 %) developed a tibial bone tunnel enlargement > 1 mm. We found a positive correlation (+ 0.59) of the grade of activity and the muscle status (+ 0.56) to the tibial bone tunnel enlargement. Patients with a major tibial bone tunnel enlargement performed at a higher (p < 0.05) postoperative activity grade (5.2 versus 4.1 in the Tegner grading), rated higher in the Lysholm (88 versus 77 points) and IKDC scores (p < 0.05) and reported a better subjective functional outcome (p < 0.05). There was no significant correlation of the results of the knee stability tests and the age of the patients to the grade of tibial bone tunnel enlargement. CONCLUSIONS: In ACL reconstruction using a patellar tendon autograft we recommend early rehabilitation as the concomitant tibial bone tunnel enlargement does not significantly influence the clinical outcome or knee stability.