Knee Meniscus Posterior Root Repair with FiberTak.

Repair of medial meniscal root tear is nowadays a validated procedure in order to restore knee biomechanics and to prevent early development of arthritis. There are various techniques described, without any being considered superior. This article describes a technique with a knotless suture anchor design, using a high posteromedial portal to insert the anchor and a meniscal suture passer device from the anteromedial portal. The technique eliminates the need for transtibial drilling and knot tying, and it certifies a strong reproducible tension.

Quadruple Semitendinosus Graft Construct With Double Cortical Suspensory Fixation for Anterior Cruciate Ligament Reconstruction: A Biomechanical Study.

The purpose of this study was to evaluate the biomechanical properties of a graft construct with quadrupled Semitendinosus and two cortical buttons with adjustable loops concerning elongation, stiffness and resistance. A total of 15 fresh human cadaveric semitendinosus tendons were quadrupled over the two adjustable loops and stitched at the tibial tip with a cerclage type suture. They underwent pre-tensioning at 300 N for 2 minutes followed by cyclic loading (1000 cycles between 50-250 N) and finally a load-to-failure test. Statistical analysis was performed using SPSS Statistics software and groups were compared using a paired t-test, with a significance level set at α = 0.05. Graft construct elongation after pre-tensioning at 300 N was 12.8 mm (9.3 mm-16.5 mm) and mean cyclic elongation 0.4 mm (0.2 mm-0.9 mm), considered significant (p < 0,001). The resistance and stiffness values were respectively 849.46 N (649.30 N-1027.90 N) and 221.49 N (178,30 N - 276.10 N). Quadruple ST graft construct using two cortical buttons and adjustable loops showed a high stiffness and resistance with a very low elongation after cycling.

Rotational alignment in patient-specific instrumentation in TKA: MRI or CT?

PURPOSE: To compare CT-guided and MRI-guided patient-specific instrumentation in total knee arthroplasty (TKA). METHODS: Forty-four patients underwent primary TKA using either CT-guided or MR-guided Signature™ patient-specific instrumentation. They were prospectively assigned into two groups: 23 patients into the MR-guided instrumentation (group A) and 21 patients into the CT-guided patient-specific instrumentation (group B). All patients underwent computed tomography of the operated knee in the first week after the surgery to measure the components rotation. RESULTS: The femoral component rotation was 0.0° (0.0, 1.0) in group A and 0.0° (-2.0, 1.0) in group B. The tibial component rotation was -16.0° (-19.0, -14.0) in group A and -15.0° (-18.0, -8.0) in group B. In both components, there were no significant differences between the two groups. The difference between the tibial component rotation and the neutral tibial rotation was similar in both groups [2.0° (-1.4, 4.0) in group A and 3.0° (-0.5, 5.0) in group B], but the dispersion around the median was different between the two groups, with the amplitude of the difference between tibial rotation and neutral position 9° (-3.0, 6.0) in group A and 27° (-9.0, 18.0) in group B. CONCLUSIONS: MRI may be more accurate than CT using the Signature™ system when planning the surgical guides for TKA, with fewer patients with malrotation of the tibial component. LEVEL OF EVIDENCE: II.

Quadruple Semitendinosus Graft Construct and Suspensory Button Fixation for Anterior Cruciate Ligament Reconstruction.

Surgical techniques for anterior cruciate ligament reconstruction are evolving, becoming less invasive, with fewer and smaller incisions, preservation of knee bone stock and tendons at the donor site, and better graft positioning and fixation. We describe an anterior cruciate ligament reconstruction technique that aims to preserve bone stock and spares the gracilis. The semitendinosus graft construct is prepared in a quadruple way and fixed with a cortical button in both tunnels, with increased stiffness and resistance of the graft construct. The tibial tunnel is filled at the end of the operation with a bone dowel, keeping the bone stock intact. This technique is safe, with a short learning curve; preserves the gracilis; saves bone; and increases the stiffness and resistance of the tibial fixation.

Patient-specific instrumentation improves tibial component rotation in TKA.

PURPOSE: To compare the femoral and tibial components rotational alignment in total knee arthroplasty (TKA) performed either with conventional or with patient-specific instrumentation. METHODS: Forty-five patients underwent primary TKA and were prospectively randomized into two groups: 22 patients into the conventional instrumentation group (group A) and 23 patients into the Signature™ patient-specific instrumentation group (group B). All patients underwent computed tomography of the operated knee in the first week after surgery to measure the components rotation. RESULTS: The femoral component rotation was 0.0° (-0.25, 1.0) in group A, and 0.0° (0.0, 1.0) in group B. The tibial component rotation was -16.0° (-18.5, 11.8) in group A, and -16.0° (-19.0, -14.0) in group B. There were no significant differences between the two groups in tibial and femoral components rotation. The difference between the tibial component rotation and the neutral tibial rotation was similar in both groups [2.0° (-0.5, 6.3) in group A and 2.0° (-1.0, 4.0) in group B], but the dispersion around the median was different between the two groups. The amplitude of the difference between tibial rotation and neutral position was 27° (-13, 14) in group A and 9° (-3, 6) in group B. CONCLUSIONS: There is a smaller chance of internal malrotation of the tibial component with the Signature™ patient-specific instrumentation system, with less dispersion and amplitude of the tibial component rotation around the neutral position. LEVEL OF EVIDENCE: II.

Is there a role for adult non-cultivated bone marrow stem cells in ACL reconstruction?

PURPOSE: To assess by magnetic resonance imaging (MRI) if adult non-cultivated bone marrow stem cells accelerate tendon-to-bone healing in the femoral tunnel, after hamstring anterior cruciate ligament (ACL) reconstruction. METHODS: Forty-three patients underwent ACL reconstruction and were prospectively randomized into two groups: 20 patients in the experimental group (group A) with adult non-cultivated bone marrow stem cells and 23 patients in the control group (group B) without adult non-cultivated bone marrow stem cells. All patients underwent MRI of the knee at three months after surgery to evaluate the signal-to-noise ratio of the interzone. RESULTS: There was no difference in the signal-to-noise ratio of the interzone on MRI between the experimental and the control group. CONCLUSIONS: Adult non-cultivated bone marrow stem cells do not seem to accelerate graft-to-bone healing in ACL reconstruction. The clinical relevance of this finding is that adult non-cultivated bone marrow stem cells apparently have a limited role in ACL reconstruction.

ACL reconstruction: effect of bone dowel on tibial tunnel enlargement.

PURPOSE: To evaluate prospectively if the impaction of a bone dowel in the tibial tunnel prevents the tunnels from enlarging beyond their original diameter. METHODS: Seventeen patients underwent arthroscopically assisted ACL reconstruction with hamstring autologous graft. All patients underwent CT of the knee on the day of surgery, at 3 months and 12 months post-op. RESULTS: On the day of surgery, the median cross-sectional areas of the tunnels were 77.0 and 79.0mm(2), respectively at 15 mm and 20mm from the tip of the posterior wall of the tunnel. At 3 months, the median cross-sectional areas of the tunnels were 70.0 and 65.0mm(2), at 15 mm and 20mm. At 12 months post-op, the median cross-sectional areas of the tunnels were 69.0 and 69.0mm(2). The median enlargement of the tunnels between 3 months and 12 months post-op was 0.0mm(2) at 15 mm and -2.0mm(2) at 20mm. CONCLUSIONS: The impaction of an autologous bone dowel in the tibial tunnel during hamstring ACL reconstruction keeps the tunnels from enlarging beyond their original diameter, and there is no further enlargement of the tunnels after 3 months post-op.

ACL reconstruction: comparison between transtibial and anteromedial portal techniques.

PURPOSE: The purpose of this study was to compare the transtibial reconstruction technique of the anterior cruciate ligament (ACL) with the anteromedial (AM) portal technique in their ability to place the femoral and tibial tunnels within the ACL footprints. METHODS: Forty patients were sequentially enrolled in two different surgical techniques, 20 patients in the transtibial and 20 patients in the AM portal technique. All patients underwent computed tomography scan of the operated knee. The center of the femoral tunnel aperture on the lateral femoral condyle was measured according to the quadrant method. On the tibial side, the center of the tibial tunnel was measured in the sagittal plane. These measurements were compared with the center of the normal AM and PL bundles. RESULTS: There were no differences in the center of the femoral tunnels on the Blumensaat's line between the two groups (mean 23.5% (4.2) for the transtibial technique and 26.0% (4.3) for the AM portal technique (P = n.s.). In the height of the femoral condyle, the center of the tunnels was significantly lower in the AM portal technique group [mean 34.7% (3.8) vs. 24.0% (7.9) (P < 0.001)]. In the tibia, the center of the tunnel in the sagittal plane was significantly posterior in the transtibial technique (mean 55.4% (4.9) vs. 44.4% (3.7) (P < 0.001). CONCLUSIONS: The AM portal technique places the femoral and tibial tunnels more centrally in the ACL footprint when compared with the transtibial technique. LEVEL OF EVIDENCE: II.

Anterior lateral meniscofemoral ligament with congenital absence of the ACL.

PURPOSE: to describe agenesis of the anterior cruciate ligament (ACL) with an anterior lateral meniscofemoral ligament. METHODS AND RESULTS: case report of a 13-year-old girl with an absent ACL and with an anterior lateral meniscofemoral ligament instead, as well as absence of the anterior insertion of the lateral meniscus in the tibia and a discoid ring-like lateral meniscus, with hypoplasia of the lateral femoral condyle. At arthroscopy, the anterior lateral meniscofemoral ligament was found to arise from the anterior horn of the lateral meniscus and insert into the posterolateral aspect of the intercondylar notch, mimicking the course of the native ACL on magnetic resonance imaging (MRI). CONCLUSION: ACL agenesis may be associated with an anomalous anterior lateral meniscofemoral ligament that may mimic a normal ACL on MRI.

Placement of femoral tunnel between the AM and PL bundles using a transtibial technique in single-bundle ACL reconstruction.

Two different approaches for drilling the femoral tunnel are commonly used in single-bundle anterior cruciate ligament (ACL) reconstruction: creating the femoral tunnel through the tibial tunnel or drilling the tunnel through a low anteromedial arthroscopy portal. When using a transtibial drilling technique, the location of the femoral tunnel is restricted by the angulation of the tibial tunnel in the coronal plane and may lead to a high placement of the femoral tunnel in the intercondylar notch. However, some authors refer that the femoral tunnel can be positioned correctly in the center of the femoral ACL footprint by means of a transtibial technique if the tibial tunnel forms an angle between 60 degrees and 65 degrees to the medial joint line of the tibia in the coronal plane. The purpose of this study was to evaluate prospectively with CT scans whether a femoral tunnel drilled through a tibial tunnel at an angle of 60 degrees-65 degrees in the coronal plane is created between the AM and PL bundles in the lateral femoral condyle. Our results showed that the median difference of the distance between the center of the femoral tunnel and the center of the AM and PL bundles along the Blumensaat's line was 6 and 5%, respectively. In the height of the femoral condyle, the median difference of the distance between the center of the femoral tunnel and the center of the AM and PL bundles was 0 and 31%, respectively. In conclusion, when drilling the femoral tunnel via a transtibial technique with the tibial tunnel angled 60 degrees-65 degrees in the coronal plane, the center of the femoral tunnel is created in the AM bundle footprint in the height of the femoral condyle.

Femoral tunnel enlargement after anatomic ACL reconstruction: a biological problem?

Tunnel enlargement after anterior cruciate ligament (ACL) reconstruction may compromise revision surgery. The cause of this tunnel enlargement is not yet fully understood, but it is thought to be multifactorial, with biomechanical and biological factors playing a role. Tunnel enlargement has been described particularly in patients who underwent ACL reconstruction with hamstring tendons with extracortical fixation devices. The purpose of our study was to evaluate prospectively with magnetic resonance imaging (MRI) the changes in femoral tunnel diameter following arthroscopic anatomic ACL reconstruction with hamstring tendons. At 3-month post-op, all tunnels had enlarged compared to the diameter of the drill and most tunnels enlarged more in the midsection than at the aperture. In the posterolateral tunnels, the entrance increased 16% in diameter and the middle of the tunnel increased 30% in diameter. In the anteromedial femoral tunnels, the tunnels enlarged 14% at the aperture and 35% in the midsection. All femoral tunnels enlarged and most of them enlarged in a fusiform manner. The biological factors explain better our findings than the mechanical theory, although mechanical factors may play a role and the cortical bone at the entrance of the tunnel may modify the way tunnels respond to mechanical stress.

Anatomic ACL reconstruction: does the platelet-rich plasma accelerate tendon healing?

Recently, the use of hamstring tendons in anterior cruciate ligament repair has been increasing. However, tendon-to-bone healing occurs slowly, which can be a problem to an early return to sport activities. The use of growth factors from platelets seems to improve tissue healing. We enrolled 40 patients in a prospective study that were submitted to an anatomic reconstruction of the anterior cruciate ligament. Patients were sequentially enrolled into four groups: group A without platelet-rich plasma (PRP); group B with PRP in femoral tunnels at the end of surgery; group C with PRP in femoral tunnels at the end of surgery and intra-articular at 2- and 4 weeks after surgery; group D with PRP activated with thrombin in the femoral tunnels. All patients underwent magnetic resonance imaging of the knee 3 months after surgery to evaluate the signal intensity of the fibrous interzone (FIZ) in the femoral tunnels. We did not find any difference among the groups when comparing the signal intensity of the FIZ on magnetic resonance imaging.