Arthroscopic Posterolateral Corner Stabilization With Popliteus Tenodesis.
ABSTRACT: The injuries of the posterolateral corner (PLC) of the knee often remain misdiagnosed. Because most structures in this anatomical region have low potential to heal, the posterolateral rotational instability results in a deterioration in patient quality of life, impaired biomechanics of the knee, and increased tension on other ligaments and the meniscus. Many open and a few arthroscopic techniques have been developed to repair or reconstruct the damaged structures of the PLC. Creating an additional midlateral arthroscopic portal on the lateral side of the knee was the key to developing the technique to recreate a static stabilizer against external rotational instability of the PLC by fixing the popliteus tendon as a native, vascularized material to the tibia.
Project description:Injuries to the posterolateral corner (PLC) often result in lateral, rotational, and dorsal instability, which need appropriate and differentiated treatment. Besides posterior cruciate ligament reconstruction for posterior instability, the technique according to LaPrade et al. efficiently stabilizes posterolateral rotational and lateral instability as described in Fanelli type B or C injuries. This technique has been exclusively used as an open procedure. In this article, we present an all-arthroscopic technique for the posterolateral stabilization procedure. To achieve this, 5 different arthroscopic portals are needed. The PLC is visualized by a trans-septal approach. Directly posterior to the popliteal tendon, arthroscopic preparation is started and the medial part of the fibular head is exposed. Two anatomic drill channels are placed in the lateral femoral condyle, with one tibial channel in the distal third of the sulcus popliteus and one channel in the fibular head. The popliteal tendon, popliteofibular ligament, and lateral collateral ligament are reconstructed with autologous hamstring tendons. The advantages of an all-arthroscopic anatomic PLC reconstruction are the protection of the soft tissues and the precise anatomic tunnel placement under direct visualization. The described procedure is a safe and anatomic method for posterolateral stabilization.
Project description:Injuries of the posterolateral corner (PLC) of the knee lead to chronic lateral and external rotational instability. Successful treatment of PLC injuries requires an understanding of the complex anatomy and biomechanics of the PLC. Several open PLC reconstruction techniques have been published. It is understood that anatomic reconstruction is superior to extra-anatomic techniques, leading to better clinical results. An open, anatomic, fibula-based technique for reconstruction to address lateral and rotational instability has been described. However, when an open technique is used, surgeon and patient are faced with disadvantages, such as soft tissue damage or exposure of vulnerable structures. Few arthroscopic techniques for tibia- or fibula-based reconstruction of rotational posterolateral instability have been described. A complete arthroscopic stabilization of the combined lateral and posterolateral rotational instability of the knee has not yet been described. We therefore present the first all-arthroscopic technique for complete PLC reconstruction, based on an open technique described previously. All relevant landmarks of the PLC can be arthroscopically visualized in detail, allowing safe and effective treatment of PLC injuries.
Project description:Isolated posterolateral corner injury is an uncommon injury that could be a source of unexplained knee pain and dysfunction. Most of these patients present instability caused by concomitant ligament injuries. Numerous studies have shown open approach posterolateral repair or reconstruction surgeries to restore posterolateral rotational stability. Still, there is a certain population of patients who present posterolateral rotation instability without significant injury to the fibular collateral ligament, popliteal fibular ligament, and popliteus tendon. The posterolateral capsular ligament is critical to provide posterolateral rotation stability. In this Technical Note, with video, we show a completely arthroscopic approach to stabilize the posterolateral corner, by stabilizing the posterior lateral joint capsule with the lateral meniscus attached to the rim of the lateral tibial plateau.
Project description:As the anatomy and biomechanics of the posterolateral corner (PLC) of the knee have become better understood, the importance of the PLC's proper function has become a more frequently raised subject. Misdiagnosed chronic posterolateral instability may lead to serious consequences, including cruciate ligament reconstruction graft failure. It has been proved that high-grade PLC injuries need to be treated operatively. Surgical approaches vary, and techniques are still developing. Considering avoidance of an extended surgical approach and minimizing the risk of common peroneal nerve or popliteal artery injuries, we developed the minimally invasive, arthroscopic-assisted, anatomic PLC reconstruction.
Project description:The posterolateral corner (PLC) of the knee is the main restraint to varus forces of the knee as well as posterolateral rotation of the tibia relative to the femur. Primary PLC repairs have been associated with a high failure rate in past literature. However, with modern improved arthroscopic instrumentation and devices, there has been a renewed interest in repair of the ligaments around the knee. Internal bracing with suture tape augmentation encourages healing and allows early mobilization. This article describes, with video illustration, PLC repair with suture tape augmentation.
Project description:The posterolateral corner (PLC) is an important stabilizer of the knee. This complex of ligaments and tendons functions as the primary restraint to varus and posterolateral rotation of the knee. Injury to the PLC can result in chronic instability, a varus-thrust gait, and early arthrosis of the medial compartment of the knee if left untreated. Several techniques have been designed to address injuries of the PLC. Over the last 30 years, our understanding of the posterolateral corner as well as its operative reconstruction evolved. This evolution has attempted to refine what is an "anatomic" reconstruction. With more improved techniques and new, innovative fixation devices, we hope to make a more favorable repair for recreating the native stability of the posterolateral corner.
Project description:We orthopaedic surgeons are not familiar with the popliteus bursa. It is defined as the expansion in the synovial membrane of the posterolateral part of the knee that lies between the lateral meniscus and the tendon of the popliteus muscle. The popliteus bursa extends approximately 1 cm distal to the joint line and has 4 borders; the medial border is the peripheral margin of the lateral meniscus, the lateral border is the popliteus tendon, and the superior and inferior borders are formed by 2 fascicles. We very rarely observe cystic lesions that expand more distally, such as pigmented villonodular synovitis (PVNS) and synovial osteochondromatosis. We consider the distally expanded bursa as the pathologic expansion of the popliteus bursa. When this expansion is involved with PVNS, it may be the cause of recurrence of PVNS in the knee joint. Synovial osteochondromatosis in this expansion may cause pain in the posterolateral corner of the knee and may become a source of free bodies in the knee joint. In such conditions, these lesions should be surgically excised. The purpose of this Technical Note is to describe a surgical approach to the pathologic expansion of the popliteus bursa.
Project description:The posterolateral corner of the knee is composed of the fibular collateral ligament, popliteus tendon, and popliteofibular ligament, which provide varus and rotational stability to the knee. An anatomic technique reconstructs these structures through 2 femoral sockets and 1 tibial and 1 fibular tunnel. This reconstruction can be performed using a peroneus longus autograft that is prepared as a Y construct. The peroneus longus autograft is preferred because it provides adequate length and diameter for the entire reconstruction. Initially, the doubled loop of the Y is passed into the tibial tunnel and fixed with an adjustable cortical button. The shorter limb of the Y is used for reconstruction of the popliteus tendon. The longer limb of the Y is passed from posterior to anterior through the fibular tunnel and is fixed in the tunnel with an interference screw to re-create the popliteofibular ligament. The remaining graft is then shuttled deep to the iliotibial band and superficial to the popliteus tendon, into the femoral socket, to re-create the fibular collateral ligament.
Project description:Posterolateral corner (PLC) structures of the knee joint comprise complex anatomical soft tissues that support static and dynamic functional movements of the knee. Most previous studies analyzed posterolateral stability in vitro under static loading conditions. This study aimed to evaluate the contributions of the lateral (fibular) collateral ligament (LCL), popliteofibular ligament (PFL), and popliteus tendon (PT) to cruciate ligament forces under simulated dynamic loading conditions by using selective individual resection. We combined medical imaging and motion capture of healthy subjects (four males and one female) to develop subject-specific knee models that simulated the 12 degrees of freedom of tibiofemoral and patellofemoral joint behaviors. These computational models were validated by comparing electromyographic (EMG) data with muscle activation data and were based on previous experimental studies. A rigid multi-body dynamics simulation using a lower extremity musculoskeletal model was performed to incorporate intact and selective resection of ligaments, based on a novel force-dependent kinematics method, during gait (walking) and squatting. Deficiency of the PLC structures resulted in increased loading on the posterior cruciate ligament and anterior cruciate ligament. Among PLC structures, the PT is the most influential on cruciate ligament forces under dynamic loading conditions.
Project description:A more complete biomechanical understanding of a combined posterior cruciate ligament and posterolateral corner knee reconstruction may help surgeons develop uniformly accepted clinical surgical techniques that restore normal anatomy and protect the knee from premature arthritic changes. We identified the in situ force patterns of the individual components of a combined double-bundle posterior cruciate ligament and posterolateral corner knee reconstruction. We tested 10 human cadaveric knees using a robotic testing system by sequentially cutting and reconstructing the posterior cruciate ligament and posterolateral corner. The knees were subjected to a 134-N posterior tibial load and 5-Nm external tibial torque. The posterior cruciate ligament was reconstructed with a double-bundle technique. The posterolateral corner reconstruction included reattaching the popliteus tendon to its femoral origin and reconstructing the popliteofibular ligament. The in situ forces in the anterolateral bundle were greater in the posterolateral corner-deficient state than in the posterolateral corner-reconstructed state at 30 degrees under the posterior tibial load and at 90 degrees under the external tibial torque. We observed no differences in the in situ forces between the anterolateral and posteromedial bundles under any loading condition. The popliteus tendon and popliteofibular ligament had similar in situ forces at all flexion angles. The data suggest the two bundles protect each other by functioning in a load-sharing, codominant fashion, with no component dominating at any flexion angle. We believe the findings support reconstructing both posterior cruciate ligament bundles and both posterolateral corner components.