Background. Total knee arthroplasty (TKA) is an effective surgical procedure to alleviate excruciating pain and correct dysfunction due to severe knee deformity. The satisfaction rate with current TKA is 80%, While 20% of the patients report uncomfortable feeling during stair descending and deeply knee bending. Preserving the ligaments might allow a restoration close to the natural function, although sacrifice of the ACL is common with the conventional TKA technique. The current
Total knee arthroplasty (TKA) was primarily considered a successful procedure, several new knee implants were introduced in recent years that seek to obtain improved stability and higher flexion. One of the implant, Vanguard XPTM BiCruciate retaining (BCR), Zinmmer-Biomet, USA recreates a specific kinematic model through the principle of normal joint. An unselected consecutive series of sixty-two patients undergoing primary TKA using the cemented total knee system between August 2016 and April 2018 were studied. Twenty-seven knees was operated using Vanguard XP, subsequently thirty-five knees were received a TKA using cruciate retaining cemented total knee system FINETMCR, Nakashimamedical, Japan. Postoperatively standing AP hip-to-ankle radiographs were obtained, from which the lower extremity mechanical axis, component angle were measured. The alignment goals were a neutral mechanical axis defined as a hip-to-ankle angle of 0°with the femoral and tibial components aligned perpendicular to the mechanical axis. The total operating time were quantified utilising an operating room database. The total operating time between TKAs performed with Vanguard XP BCR and those performed with FINE CR was compared in each group. All patients postoperatively was evaluated of clinical results the Japan Orthopedics Association(JOA) Knee scores. We evaluated femoral component posterior offset (PFCO) in both of two group. The maximal protrusion of the posterior condyle, posteriorly to the extension line parallel to the tibial shaft from the edge of the posterior tibial component was measured on true lateral radiographs.Background
Patients and Method
Bicruciate ligament retaining total knee arthroplasty preserves all of the ligaments of the knee while still addressing the ligament balance and the flexion-extension gaps. The concept of cruciate ligament preservation is not new and both Townley and Cartier designed prostheses in the late 1980s that did preserve all of the ligaments. Their results were quite acceptable for that time in knee replacement surgery but the posterior stabilised and cruciate retaining designs controlled most of the market. The surgical technique for cruciate ligament preservation was more difficult, and without clear clinical benefit, most surgeons gravitated towards the cruciate retaining and posterior stabilised designs. In the late 1990s, evaluation of the total knee arthroplasty began to assess knee kinematics in addition to pain and functional outcomes. At the same time, studies on the unicondylar knee arthroplasty demonstrated impressive scores in motion and patient satisfaction with preservation of all of the ligamentous structures of the knee. Over the past two years, new designs that preserve all of the ligaments of the knee have returned to the market. The instruments have been improved and the prostheses have been changed to respect the kinematics of the knee. Fifteen to twenty percent of all total knee replacement patients are not completely satisfied with the surgery and the authors believe that complete ligament preservation may address this complaint.
The goals of a total knee arthroplasty include approximation of the function of a normal knee and achievement of balance post-surgery. Accurate bone preparation and the preservation of natural ligaments along with a functional knee design, holds the potential to provide a method of restoring close to normal function. Although conventional knee arthroplasty is considered a successful intervention for end-stage osteoarthritis, some patients still experience reduced functionality and in some cases, require revision procedures. With conventional manual techniques, accurate alignment of the tibial component has been difficult to achieve. Even in the hands of skilled knee surgeons, outliers beyond 2 degrees of the desired alignment may occur in as many as 40%-60% of cases using conventional methods, and the range of component alignment varies considerably. Similarly, for total knee replacement outliers beyond 2 degrees of the desired alignment may occur in as many as 15% of cases in the coronal plane, going up to 40% of unsatisfactory alignment in the sagittal plane. Robotics-assisted arthroplasty has gained increasing popularity as orthopaedic surgeons aim to increase accuracy and precision of implant positioning. With advances in computer generated data, with image free data, surgeons have the ability to better predict and influence surgical outcomes. Based on planned implant position and soft tissue considerations, robotics-assisted systems can provide surgeons with virtual tools to make informed decisions for knee replacement, specific to the needs of the patient. Here, for the first time in a live surgical setting, we assess the accuracy and technique of a novel imageless semiautonomous handheld robotic surgical technique in bi-cruciate retaining total knee arthroplasty (Navio, Smith and Nephew). The system supports image-free anatomic data collection, intraoperative surgical planning and execution of the plan using a combination of robotic burring and saw cut guides.
Many fluoroscopic studies on total knee arthroplasty (TKA) have identified kinematic variabilities compared to the normal knee, with many subjects experiencing paradoxical motion patterns. The intent of this study was to investigate the results of a newly designed PCR TKA to determine kinematic variabilities and assess these kinematic patterns with those previously documented for the normal knee. The study involves determining the in vivo kinematics for 80 subjects compared to the normal knee. 10 subjects have a normal knee, 40 have a Journey II PCR TKA and 40 subjects with the Journey II XR TKA (BCR). Although all PCR subjects have been evaluated, we are continuing to evaluate subjects with a BCR TKA. All TKAs were performed by a single surgeon and deemed clinically successful. All subjects performed a deep knee bend from full extension to maximum flexion while under fluoroscopic surveillance. Kinematics were calculated via 3D-to-2D registration at 30° increments from full extension to maximum flexion. Anterior/posterior translation of the medial (MAP) and lateral (LAP) femoral condyles and femorotibial axial rotation were compared during ranges of motion in relation to the function of the cruciate ligaments.Introduction
Methods
Introduction. A common problem for patients receiving total knee arthroplasty (TKA) is postoperative functional impairment of the joint. This is minimized in bicruciate-retaining (ACL preserving) knee replacements, due to the important role of the anterior cruciate ligament (ACL) in normal kinematic patterns of the knee. We explore ACL sparing TKA by estimating the fraction of osteoarthritic TKA patients with a compatible ACL (assessed intraoperatively), while also examining potential preoperative indicators of ACL status. Method. We retrospectively examined 498 patients with a primary diagnosis of osteoarthritis who underwent a TKA by one surgeon between September 2013 and March 2015. Exclusion criteria included a prior TKA, a unicompartmental knee replacement, or inflammatory arthritis. Extensive preoperative data (within four months of surgery) for each patient was collected (anatomical alignment, extension, flexion, range of motion (ROM), Lachman test, and BMI) in addition to de-identified demographic data. The intraoperative assessment of ACL status (normal/functionally intact, compromised/deficient, or absent) was then obtained from our local database and compared with the preoperative data. IRB exemption was obtained to retrospectively collect data. Results. Intraoperative assessment of ACL status found 73.5% normal ACL, 12.9% compromised ACL, and 13.6% absent ACL. A significant demographic predictor of ACL status was gender (female - more likely intact, male - more likely absent; χ2 = 12.43, P<0.002). Patients with an intact ACL were also shown to have significantly better preoperative extension (χ2=14.83, P<0.022), flexion (F. 2, 469. = 9.93, P < 0.001), and ROM (F. 2, 469. = 9.38, P < 0.001) than those with a compromised ACL. We had a very small number of positive Lachman test results, and therefore could not draw any valid conclusion for preoperative predictive ability of the test. There was no significant difference in age, ethnicity, BMI or preoperative alignment between ACL status groups. Conclusion. Our study found 73.5% of 498 osteoarthritic TKA patients have an intact ACL. The strongest preoperative indicators of ACL status were gender, flexion, and ROM. Taken together, our results highlight a significant percentage of patients who are potential candidates for a
Introduction.
