Total knee arthroplasty (TKA) aims to alleviate pain and restore joint biomechanics to an equivalent degree to age-matched peers. Zimmer Biomet's
Aims. Total knee arthroplasty (TKA) is a common and safe orthopaedic procedure. Zimmer Biomet's
Abstract. Introduction. At our national explant retrieval unit, we identified an unusual pattern of backside-deformation on polyethylene (PE) inserts of contemporary total-knee-replacements (TKRs). The PE backside's margins were inferiorly deformed in TKRs with central-locking trays. We reported that this backside-deformation appeared to be linked to tray debonding. Moreover, recent studies have shown high-rate of tray debonding in PS
Patients planning to undergo total knee arthroplasty (TKA), especially in Asian and Middle Eastern countries, usually expect to be able to perform activities requiring knee flexion such as sitting cross-legged or kneeling with ease after the surgery. Postoperative range of motion (ROM) can be affected by multiple factors such as the patient's gender, age, preoperative ROM, diagnosis, the surgeon's technique, the pre- and post-operative rehabilitation program, and the design of the prosthesis. Among these, the choice of the prosthesis depends on the surgeon's preference. As a result, several trials and studies have been conducted to improve postoperative ROM by modifying prosthesis design. The present study aimed to examine the results of TKA with the
Introduction The NexGen-CR-Knee System ( Zimmer, Inc.) was developed for cruciate ligament retaining TKA, preserving as much of the function of the normal knee as possible. It was cleared by the FDA in 1995. Prerequisites are good bone quality and intact ligaments. It is part of a modular system for primary and some revision cases with a large selection of sizes, augmentation blocks and stem extensions. Material In the Orthopedic Center in Kassel about 1500
Aim of the study: The aim of our study is to provide a clinical and x-ray review of the
Purpose. The purpose of this study is toevaluate the clinical and radiologic results after high flexiontotal knee arthroplasty, Lospa. ®. (Corentec Inc.) with 10mm cutting of posterior femoral condyle and LPS-Flex. ®. (Zimmer Inc.) with 12.5mm cutting of posterior femoral condyle.(Fig. 1). Materials and Methods. We prospectively compared 205 knees in 128 patients who underwent arthroplasty usingLospa. ®. (groupA) and 63 knees in 48 patients who underwentarthroplasty using
INTRODUCTION. The specific factors affecting wear of the ultrahigh molecular weight polyethylene (UHMWPE) tibial component of total knee replacements (TKR) are poorly understood. One recent study demonstrated that lower conforming inserts produced less wear in knee simulators. The purpose of this study is to investigate the effect of insert conformity and design on articular surface wear of postmortem retrieved UHMWPE tibial inserts. METHODS. Nineteen
Aims. The mean age of patients undergoing total knee arthroplasty (TKA) has reduced with time. Younger patients have increased expectations following TKA. Aseptic loosening of the tibial component is the most common cause of failure of TKA in the UK. Interest in cementless TKA has re-emerged due to its encouraging results in the younger patient population. We review a large series of tantalum trabecular metal cementless implants in patients who are at the highest risk of revision surgery. Methods. A total of 454 consecutive patients who underwent cementless TKA between August 2004 and December 2021 were reviewed. The mean follow-up was ten years. Plain radiographs were analyzed for radiolucent lines. Patients who underwent revision TKA were recorded, and the cause for revision was determined. Data from the National Joint Registry for England, Wales, Northern Island, the Isle of Man and the States of Guernsey (NJR) were compared with our series. Results. No patients in our series had evidence of radiolucent lines on their latest radiological assessment. Only eight patients out of 454 required revision arthroplasty, and none of these revisions were indicated for aseptic loosening of the tibial baseplate. When compared to data from the NJR annual report, Kaplan-Meier estimates from our series (2.94 (95% confidence interval (CI) 1.24 to 5.87)) show a significant reduction in cumulative estimates of revision compared to all cemented (4.82 (95% CI 4.69 to 4.96)) or cementless TKA (5.65 (95% CI 5.23 to 6.10)). Our data (2.94 (95% CI 1.24 to 5.87)) also show lower cumulative revision rates compared to the most popular implant (PFC Sigma Cemented Knee implant fixation, 4.03 (95% CI 3.75 to 4.33)). The prosthesis time revision rate (PTIR) estimates for our series (2.07 (95% CI 0.95 to 3.83)) were lower than those of cemented cases (4.53 (95% CI 4.49 to 4.57)) from NJR. Conclusion. The
The high-flex total knee arthroplasty system was introduced to enhance knee flexion and to facilitate tibiofemoral articulation at high-flexion by the design modification of an increased thickness of the posterior wall of the femoral component by 2 mm compared with the standard total knee prosthesis. However, several clinical studies on the effectiveness of designs intended to provided high flexion following total knee arthroplasty have produced conflicting results. We performed a prospective, randomized study to compare the ranges of motion of the high-flex and standard total knee replacements in patients who were managed with simultaneous bilateral total knee arthroplasty. This study comprised of three independent groups of patients. The first group: Fifty patients (mean age, 68 years old) received a standard
Introduction. Long term data on the survivorship of cemented total knee arthroplasty (TKA) has demonstrated excellent outcomes; however, with younger, more active patients, surgeons have a renewed interest in improved biologic fixation obtained from highly porous, cementless implants. Early designs of cementless total knees systems were fraught with high rates of failure for aseptic loosening, particularly on the tibial component. Prior studies have assessed the bone ingrowth extent for tibial tray designs reporting near 30% extent of bone ingrowth . (1,2). While these analyses were performed on implants that demonstrated unacceptably high rates of clinical failure, a paucity of data exists on the extent on bone ingrowth in contemporary implant designs with newer methods for manufacturing the porous surfaces. We sought to evaluate the extent of attached bone on retrieved cementless tibial trays to determine if patient demographics, device factors, or radiographic results correlate to the extent of bone ingrowth in these contemporary designs. Methods. Using our IRB approved retrieval database, 17 porous tibial trays were identified and separated into groups based on manufacturer: Zimmer Natural Knee (1), Zimmer
Introduction. Ideally, standardized wear testing protocols replicate the in vivo motions and forces of TKR patients. In a previous study with 30 TKR patients, two distinct in vivo gait patterns emerged, one characterized as having low anteroposterior (AP-L) motion and the other high anteroposterior (AP-H) motion. The aim of this study was to determine the effect of the two in vivo-determined gait patterns on total and backside insert wear in comparison with the ISO standard 14243-3. In order to differentiate and accurately quantify topside and backside wear, a novel technique was employed where different lanthanide tracers are incorporated into the polyethylene during manufacture. Materials and Methods. Components from the Zimmer
Introduction. We compared standard
Aims. This study aimed to identify the effect of anatomical tibial component (ATC) design on load distribution in the periprosthetic tibial bone of Koreans using finite element analysis (FEA). Methods. 3D finite element models of 30 tibiae in Korean women were created. A symmetric tibial component (STC,
Introduction. Automated identification of arthroplasty implants could aid in pre-operative planning and is a task which could be facilitated through artificial intelligence (AI) and deep learning. The purpose of this study was to develop and test the performance of a deep learning system (DLS) for automated identification and classification of knee arthroplasty (KA) on radiographs. Methods. We collected 237 AP knee radiographs with equal proportions of native knees, total KA (TKA), and unicompartmental KA (UKA), as well as 274 radiographs with equal proportions of Smith & Nephew Journey and Zimmer
Total knee arthroplasty (TKA) is a common orthopaedic procedure with over 1,500 done in 2016 in Ireland alone. 96% of all TKAs are due to pain in the knee associated with osteoarthritis. According to the UK National Joint Registry (NJR), there is a 0.47%, 1.81%, 2.63% and 4.34% probability risk of undergoing a revision TKA within one, three, five and ten years respectively post-index surgery. A variety of reasons for failure of TKA have been described in the literature including infection, aseptic loosening, pain, instability, implant wear, mal-alignment, osteolysis, dislocation, peri-prosthetic fracture and implant fracture. The
[Introduction]. One of the modern design total knee arthroplasty (TKA) system, the
Introduction. Hip and knee replacements are being performed at increasing rates and currently account for one of the largest procedure expenditures in the Medicare budget. Outcomes of total knee replacement (TKR) depend on surgeon, patient and implant factors. The impact that the specific implants might have on patient-reported outcomes is unknown. The primary purpose of this study was to evaluate the patient-reported functional outcomes and satisfaction after primary total knee arthroplasty in patients with osteoarthritis who underwent TKR using five different brands of posterior-stabilized implants. Specifically, the aim was to evaluate for any difference in patient-reported outcomes based on implant brand used. The hypothesis was that there would be no difference in functional outcome that could be attributed to the implant used in primary TKR. Methods. Using our institution's total joint arthroplasty registry, we identified 4,135 patients who underwent total knee replacement (TKR) using one of the five most common implant brands used at our institution. These included Biomet Vanguard (N=211 patients), Depuy/Johnson&Johnson Sigma (N=221), Exactech OptetrakLogic (N=1,507), Smith & Nephew Genesis II (N=1,414), and Zimmer
Purpose: To investigate the stability of an uncemented Trabecular Metal (TM) tibial component we used maximum total point motion (MTPM) as determined with RSA to compare micromotion at the tibial component/bone interface between the uncemented
The purpose of this prospective study was to investigate the necessity of gender-specific design in total knee arthroplasty (TKA) for Korean women. One hundred and seventeen women (151 knees) who underwent primary TKA by one surgeon with