Takanori Iriuchishima

Evaluation of the tunnel placement in the anatomical double-bundle ACL reconstruction: a cadaver study

The objective of this study was to investigate the accurate AM and PL tunnel positions in an anatomical double-bundle ACL reconstruction using human cadaver knees with an intact ACL. Fifteen fresh-frozen non-paired adult human knees with a median age of 60 were used. AM and PL bundles were identified by the difference in tension patterns. First, the center of femoral PL and AM bundles were marked with a K-wire and cut from the femoral insertion site. Next, each bundle was divided at the tibial side, and the center of each AM and PL tibial insertion was again marked with a K-wire. Tunnel placement was evaluated using a C-arm radiographic device. For the femoral side assessment, Bernard and Hertel’s technique was used. For the tibial side assessment, Staubli’s technique was used. After radiographic evaluations, all tibias’ soft tissues were removed with a 10% NaOH solution, and tunnel placements were evaluated. In the radiographic evaluation, the center of the femoral AM tunnel was placed at 15% in a shallow–deep direction and at 26% in a high–low direction. The center of the PL bundle was found at 32% in a shallow–deep direction and 52% in a high–low direction. On the tibial side, the center of the AM tunnel was placed at 31% from the anterior edge of the tibia, and the PL tunnel at 50%. The ACL tibial footprint was placed close to the center of the tibia and was oriented sagittally. AM and PL tunnels can be placed in the ACL insertions without any coalition. The native ACL insertion site has morphological variety in both the femoral and tibial sides. This study showed, anatomically and radiologically, the AM and PL tunnel positions in an anatomical ACL reconstruction. We believe that this study will contribute to an accurate tunnel placement during ACL reconstruction surgery and provide reference data for postoperative radiographic evaluation.

Impingement Pressure in the Anatomical and Nonanatomical Anterior Cruciate Ligament Reconstruction A Cadaver Study

Background: Although the literature has extensively discussed impingement after anterior cruciate ligament (ACL) reconstruction, the definition of impingement is vague, and impingement pressure has not been well investigated as a function of tunnel position. Purpose: To determine the amount of impingement pressure between the ACL and posterior cruciate ligament (PCL) and between the ACL and notch roof in the native ACL, the single-bundle ACL reconstruction with different tunnel placements, and the anatomical double-bundle ACL reconstruction. Study design: Controlled laboratory study. Methods: Fifteen fresh-frozen nonpaired human cadaver knees were used. In each knee, different femoral and tibial tunnels were created, which allowed different graft placements. A single graft was placed in 3 positions: tibial anteromedial (AM) to femoral AM (anatomical), tibial posterolateral (PL) to femoral high AM (nonanatomical/mismatch), and tibial AM to femoral high AM. Double grafts were placed in an anatomical fashion (AM to AM and PL to PL). In each case, pressure-measuring films were inserted between the ACL and roof, the ACL and PCL, and the AM and PL bundles (for double-bundle group only). Knees were then moved with 40 N of force and from full flexion to full extension, and the pressure pattern on the film was analyzed. Results: Compared with other groups, only the AM–high AM group showed significantly higher roof impingement pressure (P < .05). There was no significant difference in PCL impingement pressure between the intact ACL group and any of the reconstructed groups. No impingement pressure was observed between the grafts in the anatomical double-bundle ACL reconstruction. Conclusion: This study evaluated the effect of different tunnel placements on the impingement pressure after ACL reconstruction. Anatomical single- or double-bundle ACL reconstruction and nonanatomical tibial PL–femoral high AM ACL reconstruction do not cause roof, PCL, and interbundle impingement. Clinical relevance: Surgeons can perform the anatomical double-bundle ACL, anatomical single-bundle, and nonanatomical tibial PL–femoral high AM reconstructions as impingement-free reconstructions.

Morphology of the tibial insertion of the posterior cruciate ligament.

BACKGROUND It has been demonstrated that double-bundle reconstruction of the posterior cruciate ligament restores knee kinematics better than does single-bundle reconstruction. The objective of this study was to identify the tibial insertion site of the posterior cruciate ligament and the related osseous landmarks to help guide surgeons in the performance of an anatomical double-bundle reconstruction of the posterior cruciate ligament. METHODS Twenty-one unpaired human cadaver knees were evaluated. The geometric data and surface features of the tibial insertion site of the posterior cruciate ligament and its bundles were studied with macroscopic observation and with three-dimensional laser photography. RESULTS The mean surface areas (and standard deviations) of the anterolateral and posteromedial insertion sites were 93.1+/-16.6 mm2 and 150.8+/-31.0 mm2, respectively, and the distance between their centers was 8.2+/-1.3 mm. The mean length and width of the anterolateral insertion site were 7.8+/-1.5 mm and 9.2+/-1.6 mm, and the mean length and width of the posteromedial insertion site were 9.4+/-1.4 mm and 15.0+/-2.7 mm. The average distances from the anterior and medial margins of the tibial plane to the center of the anterolateral insertion, defined as percentage ratios of the anteroposterior and mediolateral dimensions, were 83.4%+/-3.4% and 47.1%+/-1.9%, respectively, and the average distances from the anterior and medial margins of the tibial plane to the center of the posteromedial insertion were 95.5%+/-1.9% and 43.8%+/-2.2%. A notable change in angle, of >10 degrees, was observed between the anterolateral and posteromedial slopes in sixteen of the twenty-one knees. The average angle between the anterolateral and posteromedial slopes was 14.5 degrees+/-6.4 degrees. CONCLUSIONS The tibial insertion site of the posterior cruciate ligament and its bundles is very complex. However, the shapes and positions of the insertion sites of the two bundles are consistent in that they are located in different planes on the posterior intercondylar fossa. We noted a consistent change in slope between the tibial insertion sites of the anterolateral and posteromedial bundles.

Intercondylar roof impingement pressure after anterior cruciate ligament reconstruction in a porcine model

Anterior cruciate ligament (ACL) graft impingement against the intercondylar roof has been postulated, but not thoroughly investigated. The roof impingement pressure changes with different tibial and femoral tunnel positions in ACL reconstruction. Anterior tibial translation is also affected by the tunnel positions of ACL reconstruction. The study design included a controlled laboratory study. In 15 pig knees, the impingement pressure between ACL and intercondylar roof was measured using pressure sensitive film before and after ACL single bundle reconstruction. ACL reconstructions were performed in each knee with two different tibial and femoral tunnel position combinations: (1) tibial antero-medial (AM) tunnel to femoral AM tunnel (AM to AM) and (2) tibial postero-lateral (PL) tunnel to femoral High-AM tunnel (PL to High-AM). Anterior tibial translation (ATT) was evaluated after each ACL reconstruction using robotic/universal force-moment sensor testing system. Neither the AM to AM nor the PL to High-AM ACL reconstruction groups showed significant difference when compared with intact ACL in roof impingement pressure. The AM to AM group had a significantly higher failure load than PL to High-AM group. This study showed how different tunnel placements affect the ACL-roof impingement pressure and anterior-posterior laxity in ACL reconstruction. Anatomical ACL reconstruction does not cause roof impingement and it has a biomechanical advantage in ATT when compared with non-anatomical ACL reconstructions in the pig knee. There is no intercondylar roof impingement after anatomical single bundle ACL reconstruction.

Evaluation of the intercondylar roof impingement after anatomical double-bundle anterior cruciate ligament reconstruction using 3D-CT

PurposeTo reveal the relationship between anatomically placed anterior cruciate ligament (ACL) graft and the intercondylar roof using three-dimensional computed tomography (3D-CT).MethodsTwenty-four patients undergoing anatomical double-bundle ACL reconstruction were included in this study. Anatomical double-bundle ACL reconstruction was performed with two femoral tunnels (antero-medial; AM and postero-lateral; PL) and two tibial tunnels. Hamstring autograft was used in all cases. Six to eight weeks after operation and when the subjects had obtained full extension of the knee, 3D-CT was performed with full knee extension. In the 3D-CT, the ACL graft was also reconstructed and visualized three dimensionally. Tunnel placement was evaluated with 3D-CT and intra-operative radiographs. The extension angle of the knee was also evaluated with 3D-CT.ResultsNo intercondylar roof impingement was observed. In 12 subjects, the ACL graft touched the roof (Touch group) but no graft deformation was observed. In 12 subjects, no roof-graft contact was observed (Non-touch group). No significant difference in femoral and tibial tunnel placement was observed between the Touch and Non-touch groups. All subjects attained full knee extension.ConclusionWe believe that 3D-CT is an effective means of evaluating impingement after ACL reconstruction. For the clinical relevance, when the grafts are positioned in an anatomical fashion, there is no risk of impingement, and surgeons can perform anatomical double-bundle ACL as an impingement-free reconstruction. Level of evidence: III (Case control study).

Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction Restores Patellofemoral Contact Areas and Pressures More Closely Than Nonanatomic Single-Bundle Reconstruction

PURPOSE To investigate the effects of anterior cruciate ligament (ACL) deficiency and nonanatomic single-bundle (SB) and anatomic double-bundle (DB) ACL reconstruction on the contact characteristics of the patellofemoral (PF) joint. METHODS By use of a materials testing system, 7 fresh-frozen human cadaveric knees were tested. The following states were tested: ACL-intact knee, nonanatomic SB ACL reconstruction, anatomic DB ACL reconstruction, and ACL-deficient knee. Hamstring autografts were used. PF contact pressures and areas were measured with pressure-sensitive film at 30°, 60°, and 90° of knee flexion with a constant 100-N load on the quadriceps tendon. RESULTS The total contact area of ACL-deficient and nonanatomic SB ACL-reconstructed knees (123.8 ± 63.9 and 149.6 ± 79.3 mm(2), respectively) significantly decreased when compared with those of the intact knee (206.1 ± 83.6 mm(2)) at 30° of knee flexion. The lateral-facet peak pressure of ACL-deficient and nonanatomic SB ACL-reconstructed knees (1.12 ± 0.52 and 1.22 ± 0.54 MPa, respectively) significantly decreased when compared with those of the intact knee (0.68 ± 0.38 MPa) at 90° of knee flexion. Anatomic DB ACL reconstruction restored the contact pressures and areas to values similar to those of the intact knee (no significant difference). CONCLUSIONS ACL deficiency resulted in a significant decrease in the total and medial PF contact areas and in an increase in the lateral PF contact pressure. Anatomic DB ACL reconstruction more closely restored normal PF contact area and pressure than did nonanatomic SB ACL reconstruction. CLINICAL RELEVANCE Our findings suggest that the changes in the PF contact area and pressures in ACL deficiency and after nonanatomic SB ACL reconstruction may be one of the causes of PF osteoarthritis or other related PF problems found at long-term follow-up. Anatomic DB ACL reconstruction may reduce the incidence of PF problems by closely restoring the contact area and pressure.

Graft impingement in anterior cruciate ligament reconstruction

Anterior cruciate ligament (ACL) graft impingement is one of the most troubling complications in ACL reconstruction. In the previous strategy of isometric “non-anatomical” ACL reconstruction, posterior tibial tunnel placement and notchplasty were recommended to avoid graft impingement. Recently, the strategy of ACL reconstruction is shifting towards “anatomical” reconstruction. In anatomical ACL reconstruction, the potential risk of graft impingement is higher than in non-anatomical reconstruction because the tibial tunnel is placed at a more anterior portion on the tibia. However, there have been few studies reporting on graft impingement in anatomical ACL reconstruction. This study will provide a review of graft impingement status in both non-anatomical and the more recent anatomical ACL reconstruction techniques. In conclusion, with the accurate creation of bone tunnels within ACL native footprint, the graft impingement might not happen in anatomical ACL reconstruction. For the clinical relevance, to prevent graft impingement, surgeons should pay attention of creating correct anatomical tunnels when they perform ACL reconstruction. Level of evidence IV.

Therapeutic effect of Photodynamic therapy using Na-Pheophorbide a on osteomyelitis models in rats

OBJECTIVE In this study, we examined the therapeutic effect of photodynamic therapy (PDT) using the photosensitizer Na-Pheophorbide a (Na-Phde a) on osteomyelitis models in rats. BACKGROUND Osteomyelitis is one of the most serious infectious problems in the orthopedic field. Recently, as a new clinical approach against septic arthritis, an experimental in vivo and in vitro model for the inactivation of methicillin-resistant-Staphylococcus aureus by PDT using Na-Phde a has been developed. METHODS Methicillin-sensitive Staphylococcus aureus (MSSA) was injected into the tibia of the rats to create osteomyelitis models (n = 10, 10 legs). A total of 560 μmol/l of Na-Phde a solution was injected into five of these tibial osteomyelitis models (five legs) 48 h after the initial MSSA infection. Sixty minutes after the Na-Phde a injection, a semiconductor laser (125 mW, 670 nm) was used to irradiate the models for 10 min with a total energy of 93.8 J/mm(2). As a control group, five rats (five legs) were treated with a phosphate buffered saline injection at 48 h after MSSA infection. Weight and leg perimeter changes were plotted. Bacterial growth, histological examination and radiological examination were evaluated at 14 days after initial treatment. RESULTS PDT with Na-Phde a significantly prevented leg swelling. In the PDT group, bone destruction owing to osteomyelitis was inhibited not only histologically but also radiographically. CONCLUSIONS The results in these experiments show that PDT using Na-Phde a improved osteomyelitis in rats. This suggests that PDT using Na- Phde a can be a useful treatment for osteomyelitis.

PCL to graft impingement pressure after anatomical or non-anatomical single-bundle ACL reconstruction

BackgroundAnterior cruciate ligament (ACL) graft impingement against the posterior cruciate ligament (PCL) has been postulated, but not thoroughly investigated.PurposeTo evaluate PCL impingement pressure and biomechanical stability with different tibial and femoral tunnel positions in ACL reconstruction.MethodsIn 15 porcine knees, the impingement pressure between ACL and PCL was measured using pressure sensitive film before and after ACL single-bundle reconstruction. ACL reconstructions were performed in each knee with three different tibial and femoral tunnel position combinations: (1) tibial antero-medial (AM) tunnel to femoral AM tunnel (AM–AM), (2) tibial postero-lateral (PL) tunnel to femoral High-AM tunnel (PL–High-AM) and (3) tibial AM tunnel to femoral High-AM tunnel (AM–High-AM). Anterior tibial translation (ATT) was evaluated after each ACL reconstruction using robotic/universal force-moment sensor testing system.ResultsThere was no significant difference of the impingement pressure between AM and AM, PL–High-AM reconstructed groups and intact ACL. Only AM–High-AM ACL reconstruction group showed significantly higher impingement pressure compared with intact ACL. With regard to ATT, AM–AM group had significantly higher stiffness than PL–High-AM group.ConclusionAnatomical ACL reconstruction does not cause PCL impingement and it has biomechanical advantage in ATT when compared with non-anatomical ACL reconstructions in porcine knee. For the clinical relevance, in the anatomical ACL reconstruction, no ACL–PCL impingement is found.

The prevalence of and factors related to calcium pyrophosphate dihydrate crystal deposition in the knee joint.

OBJECTIVES The purpose of this study was to reveal the accurate prevalence and related factors to the presence of calcium pyrophosphate dihydrate (CPPD) crystal deposition in cadaveric knee joints. DESIGN Controlled laboratory study. METHODS Six hundred and eight knees from 304 cadavers (332 male knees and 276 female knees, formalin fixed, Japanese anatomical specimens) were included in this study. The average age of the cadavers was 78.3 ± 10.7 years. Knees were macroscopically evaluated for the existence of CPPD, and the depth of cartilage degeneration of the femoro-tibial joint following the Outerbridges classification. CPPD crystal was confirmed under Fourier transform infrared spectroscopy (FTIR) analysis using light microscopy. Statistical analysis was performed to reveal the correlation between the occurrence of CPPD deposition in the knee joint and gender, age, and the depth of cartilage degeneration of the femoro-tibial joint. RESULTS The prevalence of grossly visible CPPD crystal was 13% (79 knees). In all of these knees, CPPD crystal was confirmed under FTIR analysis. Statistical analysis showed significant correlation between the occurrence of CPPD deposition and gender (P < 0.001), and depth of cartilage degeneration in the femoro-tibial joint (P < 0.001). In the cartilage degeneration positive knees (Over grade 3 in Outerbridges classification), average age of CPPD deposition knee was significantly higher than CPPD negative knees. CONCLUSIONS In this study, the prevalence of CPPD deposition disease was evaluated in a relatively large sample size of cadaveric knees. The prevalence of CPPD deposition disease was 13%, and was significantly correlated with the subjects age, gender, and severity of cartilage degeneration in the femoro-tibial joint.