Implant design influences patient outcome after total knee arthroplasty: a prospective double-blind randomised controlled trial (original) (raw)
Related papers
2013
Introduction Many prosthetic design changes have been introduced in attempt to improve outcomes following TKA; however there is no consensus as to whether these changes confer benefits to patients. This study aimed to assess whether patients treated with a modern implant design had an enhanced patient outcome compared to a traditional model in a double blind randomised controlled trial. Methods 212 consecutive patients were prospectively randomised to receive either a modern (Triathlon) or a traditional (Kinemax) TKA (both Stryker Orthopaedics). 6 surgeons at a single unit performed all procedures in a standardised manner. A single researcher, blinded to implant allocation, performed all assessments. Patients were assessed pre-operatively, and at 6, 26, 52 weeks post-surgery with the Oxford Knee Score (OKS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, goniometry, timed functional assessment, lower limb power (Leg Extensor Power Rig) and pain numeric...
Does design change in total knee arthroplasty implants affect patient-reported outcomes?
BMC Surgery
Purpose The purpose of this study is to compare the early results of patient-reported outcomes between two generations of a total knee system. Methods Between June 2018 and April 2020, 121 first-generation, cemented TKAs (89 patients) and 123 s-generation, cemented TKAs (98 patients) were performed by a single surgeon. Demographic and surgical data were collected from all patients. Starting at the 6-month follow-up, patient-reported outcome measures Knee Injury and Osteoarthritis Outcome Score, Joint Reconstruction (KOOS-JR) and Knee Society (KS) clinical and radiographic scores were prospectively recorded. This study represents a retrospective review of these prospectively collected data. Results There were no statistically significant differences between the two groups in terms of demographic variables such as age, body mass index, gender and race. KOOS-JR and Knee Society (KS) scores improved significantly (p < 0.001) from their preoperative values in both device generations. ...
Clinical outcome after total knee replacement
Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA, 2015
concept of resurfacing the distal femur and proximal tibia has not changed much, and the majority of implants is still placed perpendicular to the mechanical axis. However, numerous designs have been developed over the last 40 years with the aim of achieving more natural knee kinematics. How much does the implant design affect our clinical outcome? Should we use, for instance, a fixed or a mobile design? The prospectively designed study published in the current issue did not show any difference in clinical outcome between the two designs according to the Oxford Knee Score, American Knee Society Score, Short Form-12 and range of motion [3]. The finding is in line with the Cochrane Review published earlier this year [7]. The authors of the Cochrane Review also stated that there is still a lack of evidence because many of these studies are rather of low or moderate quality. Clinical research is very demanding for different reasons. First, the study needs to be very well designed in order to be able to answer the question of interest, which should be expressed in the author's hypothesis. Secondly, patients have to be selected and followed up for a long time. This requires good compliance by the patients. Some of them may drop out, which
Open Journal of Orthopedics, 2014
There are several prosthetic knee designs currently in use. There are however very few studies comparing long-term functional outcomes between patients using different models of knee prosthesis in elective knee replacement. In this study, we used the validated Oxford Knee Score (OKS) to retrospectively compare the outcomes of a total of 1635 patients who had an elective total knee replacement in a large District General Hospital, using fifteen different models of knee prosthesis, over a ten-year period. The average scores reported by all patient groups showed significant improvement by three months post-operatively (pre-operative mean score 15.8, post-operative mean score 39.4, p < 0.05), and remained similar for all models of prosthesis used over the total ten-year period. Based on the OKS as an assessment tool, we report no significant difference in long-term functional outcomes for this group of patients following an elective knee replacement, regardless of the type of prosthesis used.
Knee, 2016
BACKGROUND: Approximately 18% of the patients are dissatisfied with the result of total knee replacement. However, the relation between dissatisfaction and prosthetic alignment has not been investigated before. METHODS: We retrospectively analysed prospectively gathered data of all patients who had a primary TKR, preoperative and one-year postoperative Oxford Knee Scores (OKS) and postoperative computed tomography (CT). The CT protocol measures hip-knee-ankle (HKA) angle, and coronal, sagittal and axial component alignment. Satisfaction was defined using a five-item Likert scale. We dichotomised dissatisfaction by combining '(very) dissatisfied' and 'neutral/not sure'. Associations with dissatisfaction and change in OKS were calculated using multivariable logistic and linear regression models. RESULTS: 230 TKRs were implanted in 105 men and 106 women. At one year, 12% were (very) dissatisfied and 10% neutral. Coronal alignment of the femoral component was 0.5 degrees more accurate in patients who were satisfied at one year. The other alignment measurements were not different between satisfied and dissatisfied patients. All radiographic measurements had a P-value>0.10 on univariate analyses. At one year, dissatisfaction was associated with the three-months OKS. Change in OKS was associated with three-months OKS, preoperative physical SF-12, preoperative pain and cruciate retaining design. DISCUSSION: Neither mechanical axis, nor component alignment, is associated with dissatisfaction at one year following TKR. Patients get the best outcome when pain reduction and function improvement are optimal during the first three months and when the indication to embark on surgery is based on physical limitations rather than on a high pain score.
Knee, 2016
BACKGROUND: Approximately 18% of the patients are dissatisfied with the result of total knee replacement. However, the relation between dissatisfaction and prosthetic alignment has not been investigated before. METHODS: We retrospectively analysed prospectively gathered data of all patients who had a primary TKR, preoperative and one-year postoperative Oxford Knee Scores (OKS) and postoperative computed tomography (CT). The CT protocol measures hip-knee-ankle (HKA) angle, and coronal, sagittal and axial component alignment. Satisfaction was defined using a five-item Likert scale. We dichotomised dissatisfaction by combining '(very) dissatisfied' and 'neutral/not sure'. Associations with dissatisfaction and change in OKS were calculated using multivariable logistic and linear regression models. RESULTS: 230 TKRs were implanted in 105 men and 106 women. At one year, 12% were (very) dissatisfied and 10% neutral. Coronal alignment of the femoral component was 0.5 degrees more accurate in patients who were satisfied at one year. The other alignment measurements were not different between satisfied and dissatisfied patients. All radiographic measurements had a P-value>0.10 on univariate analyses. At one year, dissatisfaction was associated with the three-months OKS. Change in OKS was associated with three-months OKS, preoperative physical SF-12, preoperative pain and cruciate retaining design. DISCUSSION: Neither mechanical axis, nor component alignment, is associated with dissatisfaction at one year following TKR. Patients get the best outcome when pain reduction and function improvement are optimal during the first three months and when the indication to embark on surgery is based on physical limitations rather than on a high pain score.
The patient results and satisfaction of knee arthroplasty in a validated grading system
International Orthopaedics, 2019
Introduction The validated Knee Osteoarthritis Grading System (KOGS) was implemented and clinical results were compared with patient satisfaction data and implant survivorship in a multi-centre study with surgeons familiar with unicompartmental knee arthroplasty (UKA), patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA). This is also the first study to evaluate the prevalence of UKA and TKA in consecutive osteoarthritis (OA) knee arthroplasties assessed by this system.. Method A consecutive cohort of knees was gathered at three different institutions as categorized by KOGS and surgically treated with the recommended implant unless clinical reasons or patient preference precluded such an option. One thousand one hundred seventy-seven consecutive knees were evaluated including 311 TKA (26%), 695 medial UKA (59%), 154 lateral UKA (13%) and 17 PFA (2%) and the results of the categories evaluated with the Oxford Knee Score (OKS) and the complications reflected in the different categories. Results The failure rate of the UKA (3.5%) or TKA (1.6%) is not higher than accepted results in the literature and the difference in complications is negligible between the UKA (72%) and TKA (26%) cohorts. Revision of a UKA to a TKA as an endpoint was 0.58% with ipsilateral progression at 0.8% over a period of five to 84 months (mean follow-up of 36 months) despite the 'excessive' proportion of UKA in this cohort. The Oxford Score improvement is significant in TKA and UKA and contributes to the acceptable outcomes (The OKS for TKA improved from 20 pre-operatively to 36 post-operatively and the UKA improved from 22 pre-operatively to 39 postoperatively). Conclusion KOGS achieves acceptable early survival and functional results when implemented and is a suitable tool for identifying the preferred implant as was validated.