Harehiko Tsukada

Anatomical analysis of the anterior cruciate ligament femoral and tibial footprints

BackgroundThe current trend in anterior cruciate ligament (ACL) reconstruction has shifted to anatomical double-bundle (DB) reconstruction, which reproduces both the anteromedial bundle (AMB) and the posterolateral bundle (PLB) of the ACL. Navigation systems have also been recently introduced to orthopedic surgical procedures, including ACL reconstruction. In DB-ACL reconstruction, the femoral and tibial tunnel positions are very important, but a representation of the ACL footprint under an arthroscopic view has not been established even though navigation systems have been introduced. The purpose of this study was to evaluate the anatomical footprints of both the AMB and the PLB using the representation method for application to arthroscopic DB-ACL reconstruction using a navigation system, and to evaluate the validity of the currently determined footprint position compared with other representation methods.MethodsThirty-six cadaveric knees were used for an anatomical evaluation of footprints of the AMB and PLB. On the tibial side, the ACL footprints were evaluated using an original method. On the femoral side, the ACL footprints were evaluated using Watanabe’s method and three other methods: (1) the quadrant method, (2) Mochizuki’s method, and (3) Takahashi’s method.ResultsThe central points of the ACL footprints were represented almost constantly. The present data is in accordance with previous measurement data.ConclusionThis study showed that the anatomical data of the ACL femoral and tibial footprints determined with Watanabe’s method at the femoral side and our original method at the tibial side were both applicable to arthroscopic surgery with a navigation system.

Navigation Evaluation of the Pivot-Shift Phenomenon During Double-Bundle Anterior Cruciate Ligament Reconstruction: Is the Posterolateral Bundle More Important?

PURPOSE The purpose of this study was to assess the pivot-shift phenomenon during double-bundle anterior cruciate ligament (ACL) reconstruction using a navigation system. METHODS Ninety patients who received navigated double-bundle ACL reconstruction were included in this study. The mean age of the patients was 21.9 years. During reconstruction, pivot-shift tests were performed 4 times: before reconstruction, after the posterolateral bundle fixation, after the anteromedial bundle fixation, and after the double-bundle reconstruction. Both tibial internal rotation and anterior translation under the pivot-shift test were measured at each phase by the additional functions of the navigation. The navigation system used in this study was the image-free, which does not require preoperative or intraoperative images, OrthoPilot ACL (version 2.0; B. Braun Aesculap, Tuttlingen, Germany). RESULTS Before ACL reconstruction, average (+/- standard deviation) tibial internal rotation and anterior translation under the pivot-shift test were 23.7 degrees +/- 6.1 degrees and 5.2 +/- 2.4 mm. They were significantly decreased to 20.9 degrees +/- 6.4 degrees and 2.3 +/- 1.1 mm after the posterolateral bundle fixation, and also decreased to 22.2 degrees +/- 5.7 degrees and 2.4 +/- 1.1 mm after the anteromedial bundle fixation. There was no significant difference between the groups. After double-bundle reconstruction, they improved to 20.3 degrees +/- 6.3 degrees and 2.0 +/- 1.0 mm. CONCLUSIONS Our results indicate that both the posterolateral and the anteromedial bundle similarly control both anterior translation and internal rotation during pivot-shift testing. Double-bundle reconstruction may further improve knee stability. LEVEL OF EVIDENCE Level II, development of diagnostic criteria on basis of consecutive patients with universally applied reference gold standard.

Tunnel Position and Relationship to Postoperative Knee Laxity After Double-Bundle Anterior Cruciate Ligament Reconstruction With a Transtibial Technique

Background Several laboratory studies have pointed out a potential risk of femoral tunnel misplacement in anterior cruciate ligament reconstruction with a transtibial technique. The tunnel malposition away from the anatomic attachment may result in increased postoperative knee laxity in double-bundle reconstruction. Purpose This study was conducted to evaluate the femoral and tibial tunnel positions in transtibial double-bundle reconstruction, and to determine the relationship between the tunnel positions and the results of the postoperative knee laxity examinations. Study Design Case series; Level of evidence, 4. Methods Fifty-three of 71 patients who underwent transtibial double-bundle reconstruction from 2004 to 2005 were followed more than 24 months. The tunnel positions for the anteromedial and posterolateral grafts were measured using 3-dimensional computed tomography images applying the quadrant method. The postoperative knee laxity was examined with the KT-1000 arthrometer manual maximum test, anterior drawer test, and pivot-shift test. Results The deep-shallow position (parallel to Blumensaats line) and high-low position (perpendicular to Blumensaats line) of the femoral tunnels were 27.7% ± 5.6% from the most posterior condylar contour and 16.3% ± 5.2% from Blumensaats line for the anteromedial graft, and 35.5% ± 6.4% and 48.0% ± 5.4% for the posterolateral graft. The medial-lateral and anterior-posterior positions of the tibial tunnels were 46.1% ± 2.6% from the most medial contour and 36.5% ± 4.9% from the most anterior contour for the anteromedial graft, and 47.5% ± 3.1% and 51.6% ± 5.0% for the posterolateral graft. There was no statistical correlation between any parameters of the femoral or tibial tunnel position and the results of the knee laxity tests. Conclusion The femoral tunnels placed in transtibial double-bundle reconstruction were located appropriately in high-low and deep-shallow orientation, but had larger variability than the previously reported data of the anatomic femoral attachment. However, the variability of the femoral tunnel position was not so large as to result in graft insufficiency with increased postoperative knee laxity.

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.

Stability evaluation of single-bundle and double-bundle reconstruction during navigated ACL reconstruction.

Recently, anatomic double-bundle anterior cruciate ligament (ACL) reconstructions, which reproduce the anteromedial and posterolateral bundles, have been developed to improve knee laxity. However, there are little data on the in vivo biomechanics after such reconstructions. In this paper, we will review biomechanical and clinical studies that have compared single-bundle and double-bundle reconstruction, and introduce our intraoperative evaluation of double-bundle reconstruction using a navigation system. In the navigation evaluation, knee kinematics before and after ACL reconstruction were assessed, and functions of the anteromedial and posterolateral bundles were evaluated. Although the posterolateral bundle has an important role in the knee extension position, the anteromedial bundle improved knee laxity during the more knee flexion positions. Furthermore, double-bundle reconstruction improved knee laxity compared with either posterolateral or anteromedial bundle reconstruction throughout knee range of motion. Although traditional single-bundle reconstruction, reproducing the anteromedial bundle, is a reasonable procedure, double-bundle reconstruction has the potential to improve knee stability after ACL reconstruction.

Intraoperative Comparison of Knee Laxity Between Anterior Cruciate Ligament–Reconstructed Knee and Contralateral Stable Knee Using Navigation System

PURPOSE The objective of this study was to compare knee laxity between anterior cruciate ligament (ACL)-reconstructed knees and contralateral stable knees by use of intraoperative navigation. METHODS Five patients with ipsilateral ACL-deficient knees with contralateral stable knees without any ligament injuries were included in this study. Anteroposterior (AP) knee laxity during anterior drawer force applied manually and range of tibial rotation and AP knee laxity during internal and external rotational torque applied manually in both the ACL-deficient knee and the contralateral stable knee were measured by use of a navigation system from 15 degrees to 90 degrees of knee flexion. After the temporary fixation of the posterolateral bundle, anteromedial bundle (AMB), or double-bundle (DB) reconstruction, knee laxity was measured again and compared with that of the stable knee. RESULTS The mean laxities for PLB reconstruction were significantly greater than those of the contralateral stable knee at more than 75 degrees of knee flexion (P < .05). The mean laxities for AMB or DB reconstruction were not significantly different from those of the contralateral stable knee at all knee flexion angles. Those for AMB reconstruction were within +1.6 mm and those for DB reconstruction were within -2.0 mm of those of the contralateral stable knee. The mean rotations for all reconstructions were significantly less than those of the contralateral stable knee at less than 30 degrees of knee flexion (P < .05). CONCLUSIONS DB and AMB reconstructions could restore knee laxity closer to the level of the contralateral stable knee. Because normal knee laxity is different in each individual, evaluation of contralateral stable knee laxity during ACL reconstruction surgery would be helpful for restoration to the level of the specific preinjury knee laxity. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Biomechanical evaluation of an anatomic double-bundle posterior cruciate ligament reconstruction.

PURPOSE The purpose of this study was to evaluate the effect of the anatomic double-bundle reconstruction (ADBR) of the posterior cruciate ligament (PCL) with 2 femoral tunnels and 2 tibial tunnels. METHODS Eight fresh-frozen human knees were used. Bone tunnels were created based on the PCL anatomic footprints. A 9-mm looped semitendinosus and gracilis tendon for anterolateral bundle reconstruction (ALR), a 7-mm looped semitendinosus tendon for posteromedial bundle reconstruction (PMR), and the same grafts for the ADBR were used. Under a 100-N posterior tibial load and under a 100-N posterior tibial load and 5 Nm of external tibial torque, the posterior tibial translation (PTT) was measured. RESULTS Under posterior tibial load, at 0°, the PTT of the ALR was larger than that of the intact knee (P = .04) and the ADBR (P = .03); however, there were no significant differences between the PTT of the PMR and that of the ADBR (P = .28) and intact knee (P = .99). At 30°, the PTT of the ADBR was smaller than that of the ALR (P = .02) and PMR (P = .02). At 60°, the PTT of the PMR was larger than that of the ADBR (P = .02). At 90°, the PTT of the PMR was larger than that of the ADBR (P = .02). Under posterior tibial load and external tibial torque, at 0°, the PTT of the ALR was larger than that of the ADBR (P = .04). CONCLUSIONS Although the graft size of the ADBR was larger than other reconstructions, the ADBR was better than the ALR at 0° and 30° of knee flexion under the posterior tibial load and at 0° under the combination of posterior tibial load and external tibial torque, as well as better than the PMR at 30°, 60°, and 90° of knee flexion under the posterior tibial load. CLINICAL RELEVANCE The clinical outcome of PCL reconstruction might improve by reducing posterior knee laxity in knee extension with the ADBR.

Comparison between clinical grading and navigation data of knee laxity in ACL-deficient knees

BackgroundThe latest version of the navigation system for anterior cruciate ligament (ACL) reconstruction has the supplementary ability to assess knee stability before and after ACL reconstruction. In this study, we compared navigation data between clinical grades in ACL-deficient knees and also analyzed correlation between clinical grading and navigation data.Methods150 ACL deficient knees that received primary ACL reconstruction using an image-free navigation system were included. For clinical evaluation, the Lachman, anterior drawer, and pivot shift tests were performed under general anesthesia and were graded by an examiner. For the assessment of knee stability using the navigation system, manual tests were performed again before ACL reconstruction. Navigation data were recorded as anteroposterior (AP) displacement of the tibia for the Lachman and anterior drawer tests, and both AP displacement and tibial rotation for the pivot shift test.ResultsNavigation data of each clinical grade were as follows; Lachman test grade 1+: 10.0 mm, grade 2+: 13.2 ± 3.1 mm, grade 3+: 14.5 ± 3.3 mm, anterior drawer test grade 1+: 6.8 ± 1.4 mm, grade 2+: 7.4 ± 1.8 mm, grade 3+: 9.1 ± 2.3 mm, pivot shift test grade 1+: 3.9 ± 1.8 mm/21.5° ± 7.8°, grade 2+: 4.8 ± 2.1 mm/21.8° ± 7.1°, and grade 3+: 6.0 ± 3.2 mm/21.1° ± 7.1°. There were positive correlations between clinical grading and AP displacement in the Lachman, and anterior drawer tests. Although positive correlations between clinical grading and AP displacement in pivot shift test were found, there were no correlations between clinical grading and tibial rotation in pivot shift test.ConclusionsIn response to AP force, the navigation system can provide the surgeon with correct objective data for knee laxity in ACL deficient knees. During the pivot shift test, physicians may grade according to the displacement of the tibia, rather than rotation.

Mechanisms for anterior cruciate ligament injuries in badminton

Introduction A high incidence of anterior cruciate ligament (ACL) injuries related to sports activities has been reported; however, the injury situation of ACL injury in badminton has not been elucidated. This study investigated the mechanism of ACL injury in badminton using a questionnaire. Methods Information on injury mechanism was gathered from interviews with six male and 15 female badminton players who received a non-contact ACL injury playing badminton and underwent ACL reconstruction. Results The most common injury mechanism (10 of 21 injuries) was single-leg landing after overhead stroke. Nine of 10 players had injured the knee opposite to the racket-hand side. The second most frequent injury mechanism (eight of 21 injuries) was plant-and-cut while side-stepping or backward stepping. All eight players injured the knee of the racket-hand side. Eleven injuries occurred in the rear court, and six of the 11 injuries occurred during single-leg landing after an overhead stroke. Conclusion The knee opposite to the racket-hand side tended to sustain the ACL injuries during single-leg landing after a backhand overhead stroke, whereas the knee of the racket-hand side tended to be injured by plant-and-cut during side or backward stepping. These injury patterns appear to be due to specific movements during badminton.

Biomechanical comparison between single-bundle and double-bundle anterior cruciate ligament reconstruction with hamstring tendon under cyclic loading condition

PurposeThe purpose of this study was to compare the anterior tibial translation (ATT) of the anterior cruciate ligament (ACL) reconstructed-knee between single-bundle and double-bundle ACL reconstruction under cyclic loading.MethodsSingle-bundle and double-bundle reconstructions of the knee were performed sequentially in randomized order on the same side using eight human amputated knees. After each reconstruction, the reconstructed-knee was subjected to 500-cycles of 0 to 100-N anterior tibial loads using a material testing machine. The ATT before and after cyclic loading and “laxity increase”, which indicated a permanent elongation of the graft construct, was also determined.ResultsThe ATT after cyclic loading increased in both single-bundle and double-bundle reconstruction techniques compared to that without cyclic loading. Changes in ATT before and after cyclic loading were 3.9 ± 0.9 mm and 2.9 ± 0.6 mm respectively, and were significantly different. Laxity increase was also significantly different (4.3 ± 0.9 mm and 3.2 ± 0.8 mm respectively). Although no graft rupture or graft fixation failure was found during cyclic loading, the graft deviated into an eccentric position within the tunnel.ConclusionsAlthough ATT was significantly increased in both single-bundle and double-bundle reconstruction with hamstring tendon after cyclic loading test, there was significant difference. Double-bundle reconstruction might be superior to prevent increasing ATT under cyclic loading. Deformation of hamstring tendon after cyclic loading might result in deterioration of knee stability after ACL reconstruction, and is one of disadvantages of soft tissue graft.