Postoperative evaluation of tibial footprint and tunnels characteristics after anatomic double-bundle anterior cruciate ligament reconstruction with anatomic aimers

Following anatomic double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring tendon autografts, 38 consecutive patients were evaluated with high-speed three-dimensional computed tomography. Scans were performed within 3 days following surgery. The length and width of the reconstructed ACL footprint were measured on axial images. Then, 3D images were converted into 2D with radiologic density for measurement purposes. Tunnel orientation was measured on AP and lateral views. In the sagittal plane, the center of the anteromedial (AMB) and posterolateral bundle (PLB) tibial attachment positions was calculated as the ratio between the geometric insertion sites with respect to the sagittal diameter of the tibia. In addition, the length from the anterior tibial plateau to the retro-eminence ridge was measured; the relationship of this line with the centers of the AM and PL tunnels was then measured. The AP length of the reconstructed footprint was 17.1 mm ± 1.9 mm and the width 7.3 mm ± 1.2 m. The distance from retro-eminence ridge to center of AM tunnel was 18.8 mm ± 2.8 mm, and the distance from RER to center of PL tunnel was 8.7 mm ± 2.6 mm. The distance between tunnels center was 10.1 mm ± 1.7 mm. There were no significant differences between the intra- and inter-observer measurements. The bone bridge thickness was 2.1 mm ± 0.8 mm. In the sagittal plane, the centers of the tunnel apertures were located at 35.7% ± 6.7% and 53.7% ± 6.8% of the tibia diameter for the AMB and PLB, respectively. The surface areas of the tunnel apertures were 46.3 mm² ± 4.4 mm² and 36.3 mm² ± 4.0 mm² for the AM and PL tunnels, respectively. The total surface area occupied by both tunnels was 82.6 mm² ± 7.0 mm². In the coronal plane, tunnel orientation showed the AM tunnel was more vertical than the PL tunnel with a 10° divergence (14.8° vs. 24.1°). In the sagittal plane, both tunnels were almost parallel (29.9° and 25.4° for the AM and PL tunnels, respectively). When using anatomic aimers, the morphometric parameters of the reconstructed tibial footprint in terms of length and distances to the surrounding bony landmarks were similar to the native ACL tibial footprint. However, the native footprint width was not restored, and the surface area of the two tunnel apertures was in the lower range of the published values for the native footprint area.     

Anatomical double-bundle anterior cruciate ligament reconstruction

A careful review of the literature suggests that a significant number of patients undergoing anterior cruciate ligament (ACL) reconstruction have less than optimal results. Although overall outcomes of ACL reconstruction are favourable, there remains considerable room for improvement. Anatomically, the ACL consists of two major functional bundles, the anteromedial and the posterolateral bundle. Biomechanically, both bundles contribute significantly to the anterior and the rotational stability of the knee. Therefore, anatomical double-bundle ACL reconstruction techniques may further improve the outcomes in ACL surgery. Our preferred technique for arthroscopic double-bundle ACL reconstruction includes the use of two femoral and two tibial tunnels to restore both the anteromedial and the posterolateral bundle of the ACL and their anatomical footprints at their tibial and femoral insertion site. We use two tibialis anterior tendon allografts for the restoration of the two ACL bundles. Clinical long-term outcome studies may focus on the evaluation of functional outcomes, restoration of anterior and rotational knee stability, and the risk of degenerative osteoarthritis of the knee joint following anatomical double-bundle ACL reconstruction versus single-bundle ACL reconstruction.     

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.     

Biomechanical analysis of a double-bundle posterior cruciate ligament reconstruction

The objective of this study was to experimentally evaluate a single-bundle versus a double-bundle posterior cruciate ligament reconstruction by comparing the resulting knee biomechanics with those of the intact knee. Ten human cadaveric knees were tested using a robotic/universal force-moment sensor testing system. The knees were subjected to a 134-N posterior tibial load at five flexion angles. Three knee conditions were tested: 1) intact knee, 2) single-bundle reconstruction, and 3) double-bundle reconstruction. Posterior tibial translation of the intact knee ranged from 4.9 +/- 2.7 mm at 90 degrees to 7.2 +/- 1.5 mm at full extension. After the single-bundle reconstruction, posterior tibial translation increased to 7.3 +/- 3.9 mm and 9.2 +/- 2.8 mm at 90 degrees and full extension, respectively, while the corresponding in situ forces in the graft were up to 44 +/- 19 N lower than those in the intact ligament. Conversely, with double-bundle reconstruction, the posterior tibial translation did not differ significantly from the intact knee at any flexion angle tested. This reconstruction also restored in situ forces more closely than did the single-bundle reconstruction. These data suggest that a double-bundle posterior cruciate ligament reconstruction can more closely restore the biomechanics of the intact knee than can the single-bundle reconstruction throughout the range of knee flexion.     

A new technique in double-bundle anterior cruciate ligament reconstruction with implant-free tibial fixation

Purpose

This case-series outcome study presents a surgical technique for anatomic double-bundle anterior cruciate ligament (ACL) reconstruction with 4-tunnel using two interference screws. There was a 2-year minimum follow-up.

Methods

From January to December 2009, an ACL 4-tunnel, anatomic, double-bundle reconstruction was performed on 27 patients. Double-strand hamstring tendon grafts were used in each femoral tunnel as well as two interference screws. Tibial fixation was insured through manual tension, by tying non-absorbable sutures on the bone bridge between the two tunnels at 20° of knee flexion. Clinical assessments included the International Knee Documentation Committee (IKDC) and Lysholm knee scores, range of motion (ROM), pivot-shift test, single-leg hop, and quadriceps-hamstrings strength tests using a hand-held dynamometer. Anterior knee laxity was also assessed using a rolimeter. A single examiner performed all testing pre-operatively at 6 months and during the 2-year follow-up.

Results

All patients were assessed during the 2-year follow-up. At that time, 92 % of the patients presented normal anterior laxity (average, 1.3 ± 0.5 mm) and rotational knee stability. No statistical side-to-side difference was found for ROM, muscle strength, single-leg hop, and function (n.s.). All patients presented a normal knee function according to the IKDC and the Lysholm score. In addition, no infection, graft failure, or pain were observed at the harvesting site.

Conclusion

The study shows that satisfactory results in relation to knee laxity, function, and strength can be achieved with the implant-free tibial fixation in the ACL double-bundle reconstruction with two interference screws.

Level of evidence

Therapeutic case series, Level IV.

     

Anatomical double-bundle anterior cruciate ligament reconstruction after valgus high tibial osteotomy: a biomechanical study

BACKGROUND: Although anatomical double-bundle anterior cruciate ligament reconstruction can successfully restore normal knee biomechanics for knees with typical varus-valgus alignment, the efficacy of the same reconstruction method for knees after a valgus high tibial osteotomy is unclear. HYPOTHESIS: Anatomical double-bundle anterior cruciate ligament reconstruction for valgus knees after a high tibial osteotomy cannot restore normal knee kinematics and can result in abnormally high in situ forces in the ligament graft. STUDY DESIGN: Controlled laboratory study. METHODS: Ten cadaveric knees were subjected to valgus high tibial osteotomy followed by an anatomical double-bundle anterior cruciate ligament reconstruction. The valgus knees were tested using a robotic/universal force-moment sensor system before and after the ligament reconstruction. The knee kinematics in response to anterior tibial load and combined rotatory loads, as well as the corresponding in situ forces of the anterior cruciate ligament bundles and grafts, were compared between the ligament-intact and ligament-reconstructed valgus knees. RESULTS: After reconstruction, the anterior tibial translation and internal tibial rotation for the valgus knee decreased approximately 2 mm and 2 degrees , respectively, at low flexion angles compared with those of the anterior cruciate ligament-intact knee (P < .05). The in situ forces in the posterolateral graft became 56% to 200% higher than those in the posterolateral bundle of the intact anterior cruciate ligament (P < .05). CONCLUSION: Performing an anatomical double-bundle anterior cruciate ligament reconstruction on knees after valgus high tibial osteotomy may overconstrain the knee and result in high forces in the posterolateral graft, which could predispose it to failure. CLINICAL RELEVANCE: Modifications of anterior cruciate ligament reconstruction procedures to reduce posterolateral graft force may be needed for valgus knees after a high tibial osteotomy.     

Intraoperative comparisons of knee kinematics of double-bundle versus single-bundle anterior cruciate ligament reconstruction

Purpose  

Based on biomechanical anatomical studies, double-bundle reconstruction of the anterior cruciate ligament (ACL) was introduced to achieve better stability in the knee, particularly in respect of rotatory loads. An in vivo, computer-assisted, double-bundle (DB) ACL reconstruction is superior to a single-bundle (SB) ACL reconstruction at reducing rotatory, and AP laxities of the tibia at 20 degrees of knee flexion and also during the pivot shift test.     

Magnetic resonance imaging of double-bundle anterior cruciate ligament reconstruction

Reconstruction of the anterior cruciate ligament (ACL) using the double-bundle technique is getting highly increasing attention. This surgical approach uses two separate tendon grafts with the intention to reconstruct both anatomic bundles in order to restore the full biomechanical function of the original ligament. With the increasing popularity of this technique, radiologists will be more frequently confronted with patients who underwent this surgical procedure. The aims of this essay are to briefly describe the basic biomechanical and surgical principles and to summarize the magnetic resonance imaging findings of the knee after double-bundle ACL reconstruction. Grants or Funding None.     

Clinical comparison of two suspensory fixation devices for anatomic double-bundle anterior cruciate ligament reconstruction

Purpose

The aim of this study was to compare the operation time required and the clinical outcome 2?years postoperatively, after anatomic double-bundle ACL reconstructions using hamstring tendon grafts fixed with either the EndoButton-CL-BTB^? (ECL-BTB) or the EndoButton-CL^? (ECL).

Methods

Forty-six patients, who underwent anatomic double-bundle ACL reconstruction, were non-randomly divided into 2 groups. Patients with a combined ligament injury or complete meniscal tear were excluded from this study. In group I, an ECL was used with 23 patients. In group II, an ECL-BTB was used with the remaining 23 patients. In groups I and II, the ECL or ECL-BTB was attached to the femoral ends of the hamstring tendon autografts. In both groups, a polyester tape was connected in series with the tibial ends of the grafts. The patients were examined with standard clinical evaluations at 2?years after surgery.

Results

The operation time in group II was significantly shorter than that in group I (P?=?0.0459). Concerning the intra- and postoperative complications, there were no serious complications in either group. No significant differences were found between the 2 groups in terms of knee laxity measurements, the peak muscle torque of quadriceps and hamstrings, the Lysholm score and the IKDC evaluation.

Conclusions

This study demonstrated that the usage of the ECL-BTB for graft preparation significantly shortens the total operation time in comparison with the ECL and that there were no significant differences in the 2-year clinical outcome and the intra- and postoperative complications between the 2 graft preparation procedures of the anatomic double-bundle ACL reconstruction. The ECL-BTB can be an alternative device for the hamstring tendon graft in double-bundle ACL reconstruction.

Level of evidence

Prospective comparative cohort study, Level II.     

The double-bundle technique for anterior cruciate ligament reconstruction: a systematic overview

In traditional anterior cruciate ligament reconstruction, there is a subset of patients complaining of knee instability, especially rotational instability, and athletes not able to return to their preinjury level of sports activity. Currently, controversy exists over the usefulness of the double bundle technique (DBT) in addressing these problems. In order to evaluate the DBT, we completed a literature review from 1969 to February 2006 focusing on anatomy, magnetic resonance imaging, graft incorporation, biomechanics, kinematics, surgical techniques, complications and outcome. The DBT is not a standardized technique, which makes it difficult to compare results. Cadaver studies have proven biomechanical advantages with respect to ap-stability, but assessing the rotational stability remains difficult. There is a lack of available outcome studies with sufficient follow-up to demonstrate the potential advantages of DBT. The theoretical advantages of DBT require careful evaluation with outcome, biomechanical and kinematic studies. In addition, studies are needed to address issues such as graft incorporation and complications. An advantage offered by DBT is the possibility to identify rupture patterns that can lead to surgical preservation of an intact and augmentation of an injured bundle. The approach of augmentating a single bundle technique reconstruction with adequate anterior-posterior but poor rotational stability is promising.     

Factors affecting anterior knee pain following anatomic double-bundle anterior cruciate ligament reconstruction

Purpose

The purpose of this study was to evaluate the prevalence of anterior knee pain in anatomic double-bundle anterior cruciate ligament (ACL) reconstruction and to identify critical factors affecting postoperative anterior knee pain development.

Methods

Subjects comprised 171 patients (171 knees) who underwent anatomic double-bundle ACL reconstruction with a follow-up period of ≥2?years. The procedure used bone-patellar tendon-bone plus gracilis tendon (BTB-G) in 56 knees, semitendinosus tendon (ST) in 71 knees, and ST-G in 44 knees. Clinical results and prevalence and severity of anterior knee pain were assessed at 3?months and 2?years postoperatively. Clinical variables influencing anterior knee pain development at each postoperative period were subjected to univariate analysis, followed by logistic regression analysis to identify risk factors for anterior knee pain.

Results

Overall prevalences of anterior knee pain at 3?months and 2?years postoperatively were 42.0 and 11.1%, respectively. Use of BTB-G graft represented the highest prevalence of anterior knee pain between the 3 different grafts (P?=?0.001); however, this statistical significance disappeared at 2?years postoperatively. Prevalence of postoperative extension deficit was significantly higher in anterior knee pain-positive cohort than in anterior knee pain-negative cohort at 3?months postoperatively. Level of quadriceps strength was significantly lower, and Lysholm score was significantly worse in anterior knee pain-positive cohort than in anterior knee pain-negative cohort at 2?years postoperatively. According to logistic regression analysis, knee extension deficit was a predisposing factor for the development of anterior knee pain at 3?months postoperatively (odds ratio, 2.76; P?=?0.004); however, there was no significant predisposing factor for anterior knee pain at 2?years postoperatively.

Conclusions

Knee extension deficit was an important predisposing factor for postoperative anterior knee pain in the early postoperative period, and anterior knee pain was associated with impaired quadriceps function and inferior subjective results over 2?years postoperatively. Early recovery of full extension may prevent postoperative development of anterior knee pain and achieve successful outcomes for ACL reconstruction.

Level of evidence

Retrospective comparative study, Level III.