Anatomically oriented anterior cruciate ligament reconstruction with a bone-patellar tendon-bone graft via rectangular socket and tunnel: a snug-fit and impingement-free grafting technique

The arrangement and the attachment areas of three ACL bundles

PURPOSE

Normal anterior cruciate ligament (ACL) can be divided into three fiber bundles-i.e., anteromedial (AM), intermediate (IM), and posterolateral (PL) bundles. However, their arrangement and attachment areas had remained unclear. The purpose of this study was to clarify the arrangement of these three ACL fiber bundles and their attachment sites, and to provide information on the tunnel placement in anatomical triple bundle ACL reconstruction.

METHODS

Seven non-embalmed human frozen knees were used. ACL fibers were bluntly divided into three bundles. A different-colored thread was wound around each fiber bundle in a spiral. Macroscopical investigation was performed to clarify the arrangement of three ACL bundles. Each fiber bundle was carefully detached from the femur and tibia, and then the distribution of attachment sites of each fiber bundle was observed.

RESULTS

In knee extension, all bundles consisting of AM, IM and PL bundles ran parallel to each other in the lateral view from the medial side. The AM bundle overlapped with the IM bundle, whereas the PL bundle ran parallel to them on the distal aspects. As the knee flexion increased, the bundles became twisted around each other. On the tibial side, the attachment areas of three fiber bundles formed a triangular shape showing arrangements of AM, IM and PL bundles on the anteromedial, anterolateral and posterior aspects, respectively. On the femoral side, the PL bundle was attached on the distal-posterior areas; the IM bundle was attached distal-anterior to the AM bundle. They were arranged in a triangular shape on the tibia side as well.

CONCLUSION

This study clarified the arrangement of three fiber bundles of ACL and detailed geographical locations of their attachment sites. The detailed anatomic description of the natural ACL attachment might suggest to surgeons where to make tunnels during anatomical double/triple bundle ACL reconstruction.

Early integration of a bone plug in the femoral tunnel in rectangular tunnel ACL reconstruction with a bone-patellar tendon-bone graft: a prospective computed tomography analysis

PURPOSE

The purpose of this prospective study was to evaluate how early the bone plug was integrated into the rectangular femoral tunnel after anatomical ACL reconstruction using a bone-patellar tendon-bone (BTB) graft via a rectangular tunnel (RT BTB ACL-R).

METHODS

Twenty consecutive patients who had undergone the reconstruction procedure were evaluated by CT scans at 4 and 8 weeks postoperatively. In each scan, 30 slices for multiplanar reconstruction were collected parallel to the long axis of the parallelepiped femoral tunnel and perpendicular to the tendinous plane of the bone plug. Each slice was classified as "complete," indicating no visible gap between the plug and the tunnel wall or trabecular continuity or "incomplete," showing a visible gap. Bone plug-tunnel integration was evaluated as "excellent," "good," "fair," or "poor" for >20, 11-20, 5-10, and <4 "complete" slices, respectively.

RESULTS

In this evaluation, 55% of the patients were rated as "excellent" on the first scan, and 80% were "excellent" on the second scan, showing healing over time. The CT values at the anterior interface between the bone plug and the tunnel wall were also measured on both scans. The mean changes in CT value at 8 weeks were significantly lower than those at 4 weeks.

CONCLUSION

This study shows that bone plug-femoral tunnel integration was almost complete by 8 weeks after surgery using RT BTB ACL-R.

Anatomical placement of double femoral tunnels in anterior cruciate ligament reconstruction: anteromedial tunnel first or posterolateral tunnel first?

PURPOSE

The purpose of this study was to know which tunnel--the anteromedial (AM) bundle or the posterolateral (PL) bundle--should be prepared first to create the 2 femoral tunnels accurately in anatomic double-bundle (DB) anterior cruciate ligament (ACL) reconstruction.

METHODS

Thirty-four patients were divided into 2 groups of 17 depending on the sequence of preparation of the 2 femoral tunnels. In group A, the AM tunnel was prepared first, whereas the PL tunnel was prepared first in group P. ACL reconstruction was performed using a three-dimensional (3-D) fluoroscopy-based navigation system to place the double femoral tunnels through an accessory medial portal. The double femoral socket positioning was evaluated by 3-D computed tomography (CT) scan image.

RESULTS

The non-anatomical placement of the femoral sockets occurred in 5 patients (29%) in group A, whereas the 2 sockets were placed anatomically in all patients in group P (P < 0.05). Evaluation of the AM and the PL socket location on the 3-D CT images using the quadrant method showed more similar values to the laboratory data in a literature in group P than in group A. No complication occurred in group A, whereas complications such as socket communications or back wall blowout occurred in 5 patients (29%) in group P (P < 0.05).

CONCLUSION

The sequence of creating 2 femoral tunnels through accessory medial portal affected the resultant location of the sockets and the rate of the complications. When femoral tunnels are prepared with a transportal technique, PL tunnel first technique seems to be superior to AM first technique regarding anatomic placement. However, PL tunnel first technique accompanies the risk of socket communication.

The transtibial versus the anteromedial portal technique in the arthroscopic bone-patellar tendon-bone anterior cruciate ligament reconstruction

The transtibial (TT) drilling of the femoral tunnel in the bone-patellar tendon-bone (BPTB) anterior cruciate ligament (ACL) reconstruction was found to place the tunnel non-anatomically. The use of the anteromedial portal (AMP) for the femoral drilling would provide the surgeon with more freedom to anatomically place the tunnel in the real femoral ACL footprint. The purpose of this study was to compare the clinical outcomes of BPTB ACL reconstruction using the AMP or the TT technique for the femoral tunnel drilling. A Medline search was not able to identify any study directly comparing the clinical outcomes of the AMP and the TT techniques. The literature search identified experimental and quasi-experimental studies published from 1966 to March 2009 where at least one group underwent arthroscopic autologous BPTB ACL reconstructions using either the AMP or the TT technique for the femoral tunnel drilling. Overall IKDC, Lysholm score, activity level, range of motion, single-leg hoop test, Lachman test, Pivot shift sign test, KT-1000 arthrometer measurements, and radiographic assessments were indirectly compared between the two groups (AMP versus TT). Twenty-one studies, involving a total of 859 patients (257 in the AMP and 602 in the TT group), were included in this analysis. The AMP group demonstrated significantly earlier return to run and significantly greater range of motion, Lachman test values, and KT-1000 arthrometer measurements in the 1-2-year follow-up, although no differences were found for both the 3-5 and the 6-10-year follow-ups for any of these parameters. In contrast, the TT group demonstrated significantly higher activity level for the 3-5 and 6-10-year follow-up. The use of the AMP elicited greater knee stability and range of motion values, and earlier return to run compared to the TT technique. These results may indicate a potential benefit of the AMP over the TT technique. However, as the benefits of the AMP were not obtained in the mid and long-term follow-ups, overall there is no definitive evidence at this point to conclude that one technique is superior to the other. Randomized controlled trials directly comparing the use of both techniques with long-term follow-ups will help clarify which one, if any, provides best clinical outcomes.

The effect of intra-operative knee flexion angle on determination of graft location in the anatomic double-bundle anterior cruciate ligament reconstruction

Graft tunnel placement is the factor with most influence on the outcome of double-bundle anterior cruciate ligament (ACL) reconstruction. However the final decision for the graft location has to be decided subjectively under arthroscopy, and can be misplaced due to the effect of the knee flexion angle. The displacement of the estimated placement by surgeons from the ACL anatomical attachment is due to the knee's differing knee flexion angle. Eight cadaveric knees and an electromagnetic position recording system were employed. After digitizing the anatomical location of AM and PL bundle center, four experienced surgeons estimated the graft placement repeatedly at 70 degrees , 90 degrees and 110 degrees of knee flexion. The displacements between these two positions were calculated and analyzed separately in antero-posterior and disto-proximal directions. The displacements of the estimated AM bundle placements were 4.7 +/- 3.4 mm at 70 degrees , 4.3 +/- 2.2 mm at 90 degrees , and 6.0 +/- 2.6 mm at 110 degrees , while those of the PL bundle were 4.0 +/- 2.2 mm at 70 degrees , 3.4 +/- 1.9 mm at 90 degrees , and 4.2 +/- 2.5 mm at 110 degrees . The best results were obtained at 90 degrees of knee flexion. Additionally, the estimated placements for both AM and PL bundle were located more distally as the flexion angle increased. Our results imply that the knee should be set at 90 degrees when determining the graft placement in double-bundle reconstruction to prevent misplacement of the graft usually in a disto-proximal direction.

Biomechanical comparison of single-tunnel-double-bundle and single-bundle anterior cruciate ligament reconstructions

BACKGROUND

Anatomic double-bundle reconstruction has been thought to better simulate the anterior cruciate ligament anatomy. It is, however, a technically challenging procedure, associated with longer operation time and higher cost.

HYPOTHESIS

Double-bundle anterior cruciate ligament reconstruction using a single femoral and tibial tunnel can closely reproduce intact knee kinematics.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight fresh-frozen human cadaveric knee specimens were tested using a robotic testing system to investigate the kinematic response of the knee joint under an anterior tibial load (130 N), simulated quadriceps load (400 N), and combined torques (5 N.m valgus and 5 N.m internal tibial torques) at 0 degrees, 15 degrees, 30 degrees, 60 degrees, and 90 degrees of flexion. Each knee was tested sequentially under 4 conditions: (1) anterior cruciate ligament intact, (2) anterior cruciate ligament deficient, (3) single-bundle anterior cruciate ligament reconstruction using quadrupled hamstring tendon, and (4) single-tunnel-double-bundle anterior cruciate ligament reconstruction using the same tunnels and quadrupled hamstring tendon graft as in the single-bundle anterior cruciate ligament reconstruction.

RESULTS

Single-tunnel-double-bundle anterior cruciate ligament reconstruction more closely restored the intact knee kinematics than single-bundle anterior cruciate ligament reconstruction at low flexion angles (< or =30 degrees ) under the anterior tibial load and simulated muscle load (P < .05). However, single-tunnel-double-bundle anterior cruciate ligament reconstruction overconstrained the knee joint at high flexion angles (> or =60 degrees ) under the anterior tibial load and at 0 degrees and 30 degrees of flexion under combined torques.

CONCLUSION

This double-bundle anterior cruciate ligament reconstruction using a single tunnel can better restore anterior tibial translations to the intact level compared with single-bundle anterior cruciate ligament reconstruction at low flexion angles, but it overconstrained the knee joint at high flexion angles.

CLINICAL RELEVANCE

This technique could be an alternative for both single-bundle and double-tunnel-double-bundle anterior cruciate ligament reconstructions to reproduce intact knee kinematics and native anterior cruciate ligament anatomy.

Anterior cruciate ligament reconstruction associated with extra-articular tenodesis: A prospective clinical and radiographic evaluation with 10- to 13-year follow-up

BACKGROUND

This study was undertaken to prospectively analyze, at a mean 11-year follow-up, the clinical and radiographic outcomes in patients undergoing the authors' intra-articular anterior cruciate ligament reconstructive procedure with extra- articular augmentation, and to compare these data with those at 5-year follow-up.

PURPOSE

The clinical and radiographic outcomes in patients undergoing anterior cruciate ligament reconstruction were analyzed at a mean 11-year follow-up.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The authors studied 54 of 60 consecutive high-level sports patients who underwent their anterior cruciate ligament reconstruction technique between 1993 and 1995. The surgical technique uses the hamstring tendons with intact tibial insertions for intra-articular double-stranded reconstruction plus an extra-articular plasty (augmentation) performed with the remnant part of the tendons. Clinical and radiographic evaluations were performed.

RESULTS

After 11 years, the International Knee Documentation Committee score demonstrated good or excellent results (A and B) in 90.7% of patients. Ligament arthrometry using the KT-2000 arthrometer demonstrated that only 2 patients had >5 mm manual maximum side-to-side difference in laxity. The mean Tegner activity score was 4.5, while the mean Lysholm score was 97.3 and the mean subjective score was 90.0%. Radiographic evaluation demonstrated progressive joint narrowing only for the 20 patients having concomitant medial meniscal surgery.

CONCLUSION

The original technique demonstrates highly satisfactory results. Factors negatively affecting the outcomes are meniscectomy and laxity. In this series, anterior cruciate ligament reconstruction with lateral plasty shows maintenance of knee stability at long-term follow-up. Knee osteoarthritis after anterior cruciate ligament reconstruction with extra-articular tenodesis does not appear to be greater than after anterior cruciate ligament reconstructions without extra-articular augmentation as reported in historical controls.

Comparable results between lateralized single- and double-bundle ACL reconstructions

Patellar tendon autografts are not suitable for multibundle ACL reconstruction, a procedure that reportedly enhances postoperative knee stability. Biomechanical studies recommend lateral placement of the femoral tunnel for single-bundle reconstruction to improve postoperative knee kinematics. We asked whether a lateralized single-bundle patellar tendon graft (LSBP) would provide good short-term results of ACL reconstruction comparable to double-bundle hamstring tendon grafts (DBH). We prospectively followed 144 patients with unilateral ACL rupture treated with either LSBP or DBH in a nonrandomized fashion. Twenty-four female and 31 male patients with LSBP and 44 female and 26 male patients with DBH were followed for a minimum of 24 months (average, 38 months; range, 24-56 months). The patients with LSBP recovered knee extension better at 1 month compared with the patients with DBH, but extension was similar after 3 months. We observed no differences in the side-to-side difference of KT1000 measurement, pivot shift test, or anterior drawer test between LSBP and DBH. Although better recovery of hamstring strength in LSBP and better recovery of quadriceps strength in DBH were observed in the early postoperative period, these differences disappeared after 12 months. There was no difference in International Knee Documentation Committee objective evaluation between LSBP and DBH at the final followup.

LEVEL OF EVIDENCE

Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Intraoperative biomechanical evaluation of anatomic anterior cruciate ligament reconstruction using a navigation system: comparison of hamstring tendon and bone-patellar tendon-bone graft

BACKGROUND

Recently, more anatomic anterior cruciate ligament reconstructions have been developed to improve knee laxity.

PURPOSE

The objective of this study is to assess knee kinematics after double-bundle reconstruction with hamstring tendon and after anatomically oriented reconstruction with a patellar tendon using navigation during surgery.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Eighty knees received double-bundle reconstruction with a hamstring tendon graft, and 45 knees received anatomically oriented reconstruction with a patellar tendon graft. Before reconstruction, knee laxity was measured using a navigation system. After the posterolateral bundle or anteromedial bundle was temporarily fixed during double-bundle reconstruction, knee laxity was measured to assess the function of each bundle. After double-bundle reconstruction or anatomically oriented reconstruction with patellar tendon, knee laxity was measured in the same manner.

RESULTS

Both double-bundle reconstruction and anatomically oriented reconstruction similarly improved knee laxity compared with before reconstruction in all knee flexion angles. Regarding the function of the anteromedial and posterolateral bundles in double-bundle reconstruction, the 2 grafts showed contrasting behavior. The posterolateral bundle restrained tibial displacement mainly in knee extension, whereas the anteromedial bundle restrained it more in the knee flexion position. The posterolateral bundle has a more important role in controlling rotation of the tibia than the anteromedial bundle.

CONCLUSION

Although the posterolateral bundle has an important role in the extension position, the anteromedial bundle is more important in the flexion position. Therefore, both bundles should be reconstructed to improve knee laxity throughout knee range of motion. Even with single-bundle reconstruction using a patellar tendon, anatomic reconstruction might improve knee laxity similar to double-bundle reconstruction.

Radiologic evaluation of femoral and tibial tunnels created with the transtibial tunnel technique for anatomic double-bundle anterior cruciate ligament reconstruction

PURPOSE

The purpose of this study was to clarify femoral and tibial tunnel angles in anatomic double-bundle anterior cruciate ligament (ACL) reconstruction.

METHODS

A prospective study was performed in 50 consecutive patients who underwent anatomic double-bundle ACL reconstruction via hamstring tendon grafts for chronic ACL deficiency in the unilateral knee. For this procedure, 2 hamstring tendon grafts were secured with EndoButtons (Smith & Nephew Endoscopy, Andover, MA) on the femur and with 2 staples on the tibia. Each patient underwent radiologic examination 1 year after surgery.

RESULTS

The tibial tunnel angles of the posterolateral bundle averaged 40.7 degrees in the anteroposterior view and 35.4 degrees in the lateral view. The tibial tunnel angles of the anteromedial bundle averaged 15.6 degrees in the anteroposterior view and 41.4 degrees in the lateral view. The femoral tunnel angles of the posterolateral bundle averaged 44.0 degrees in the anteroposterior view and 52.0 degrees in the lateral view. The femoral tunnel angles of the anteromedial bundle averaged 18.0 degrees in the anteroposterior view and 49.8 degrees in the lateral view.

CONCLUSIONS

The given data will be useful for surgeons to evaluate the tunnel positions and standardization postoperatively in anatomic double-bundle reconstruction.

LEVEL OF EVIDENCE

Level II, development of diagnostic criteria on the basis of consecutive patients with universally applied reference gold standard.

Anatomic double bundle ACL reconstruction: a literature review

With the abundance of anatomic double bundle ACL reconstruction techniques that currently exist and limited patient outcome data, one has to ask whether or not they should be used and if so, which one, and what is the learning curve for the average knee surgeon to become competent with the technique that they select? The purpose of this literature review is to summarize existing anatomic double bundle ACL reconstruction surgical and rehabilitation techniques and the clinical and biomechanical study evidence that currently exists. In choosing to perform anatomic double bundle ACL reconstruction we suggest that the knee surgeon should look for evidence of: (1) control of the pivot shift phenomenon, (2) improved transverse plane rotatory knee control during the performance of sports type movements, (3) a decreased likelihood of revision procedures either for ACL reconstruction or for treatment of associated primary or recurrent meniscal injuries, (4) improved patient self-reports of perceived function, satisfaction, and quality of life, and (5) radiographic evidence of a lower incidence and/or magnitude of osteoarthritic changes compared to conventional single bundle ACL reconstruction.