Aims. Meeting preoperative expectations is known to be of major influence on postoperative satisfaction after total knee arthroplasty (TKA). Improved management of expectation, resulting in more realistic expectations can potentially lead to higher postoperative satisfaction. The objective of this study was to assess the effect of an additional preoperative education module, addressing realistic expectations for long-term functional recovery, on postoperative satisfaction and expectation fulfilment. Methods. In total, 204 primary TKA patients with osteoarthritis were enrolled in this randomized controlled trial (RCT). Patients were allocated to either usual preoperative education (control group) or usual education plus an additional module on realistic expectations (intervention group). Primary outcome was being very satisfied (numerical rating scale for satisfaction ≥ 8) with the treatment result at 12 months' follow-up. Other outcomes were change in preoperative expectations and postoperative expectation fulfilment. Results. A total of 187 patients (91.7%) were available for analysis at follow-up. In the intention-to-treat analysis, 58.5% (55/94) of patients were very satisfied with the treatment result in the control group, and 69.9% (65/93) of patients in the intervention group (adjusted odds ratio (AOR) 1.72, 95% confidence interval (CI) 0.90 to 3.29). A per-protocol analysis for patients who attended the education session (92.0%, n = 172) showed that 56.9% (49/86) of patients were very satisfied in the control group and 74.4% (61/86) in the intervention group (AOR 2.44, 95% CI 1.21 to 4.91). After preoperative education, the expectation scores in the intervention group were significantly lower (mean difference -6.9 (95% CI -10.2 to -3.6)) and did not alter in the control group (mean difference 0.5 (95% CI -2.9 to 3.9)). Overall, fulfilment of expectations at 12 months was significantly higher in the intervention group (mean difference 11.4% (95% CI 2.3 to 20.5)). Conclusion. Improved preoperative patient education can modify patient expectations, resulting in higher postoperative fulfilment of expectation and higher satisfaction in the group that attended the preoperative education. This is the first RCT to confirm the potential of improved expectation management on satisfaction after TKA. Cite this article: Bone Joint J 2021;103-B(4):619–626

Aims

This study investigated the influence of body mass index (BMI) on patients’ function and quality of life ten years after total knee arthroplasty (TKA).

Aims. The primary aim was to assess whether robotic total knee arthroplasty (rTKA) had a greater early knee-specific outcome when compared to manual TKA (mTKA). Secondary aims were to assess whether rTKA was associated with improved expectation fulfilment, health-related quality of life (HRQoL), and patient satisfaction when compared to mTKA. Methods. A randomized controlled trial was undertaken, and patients were randomized to either mTKA or rTKA. The primary objective was functional improvement at six months. Overall, 100 patients were randomized, 50 to each group, of whom 46 rTKA and 41 mTKA patients were available for review at six months following surgery. There were no differences between the two groups. Results. There was no difference between rTKA and mTKA groups at six months according to the Western Ontario and McMaster Universities osteoarthritis index (WOMAC) functional score (mean difference (MD) 3.8 (95% confidence interval (CI) -5.6 to 13.1); p = 0.425). There was a greater improvement in the WOMAC pain score at two months (MD 9.5 (95% CI 0.6 to 18.3); p = 0.037) in the rTKA group, although by six months no significant difference was observed (MD 6.7 (95% CI -3.6 to 17.1); p = 0.198). The rTKA group were more likely to achieve a minimal important change in their WOMAC pain score when compared to the mTKA group at two months (n = 36 (78.3%) vs n = 24 (58.5%); p = 0.047) and at six months (n = 40 (87.0%) vs n = 29 (68.3%); p = 0.036). There was no difference in satisfaction between the rTKA group (97.8%; n = 45/46) and the mTKA group (87.8%; n = 36/41) at six months (p = 0.096). There were no differences in EuroQol five-dimension questionnaire (EQ-5D) utility gain (p ≥ 0.389) or fulfilment of patient expectation (p ≥ 0.054) between the groups. Conclusion. There were no statistically significant or clinically meaningful differences in the change in WOMAC function between mTKA and rTKA at six months. rTKA was associated with a higher likelihood of achieving a clinically important change in knee pain at two and six months, but no differences in knee-specific function, patient satisfaction, health-related quality of life, or expectation fulfilment were observed. Cite this article: Bone Joint J 2023;105-B(9):961–970

Aims. The aim was to assess whether robotic-assisted total knee arthroplasty (rTKA) had greater knee-specific outcomes, improved fulfilment of expectations, health-related quality of life (HRQoL), and patient satisfaction when compared with manual TKA (mTKA). Methods. A randomized controlled trial was undertaken (May 2019 to December 2021), and patients were allocated to either mTKA or rTKA. A total of 100 patients were randomized, 50 to each group, of whom 43 rTKA and 38 mTKA patients were available for review at 12 months following surgery. There were no statistically significant preoperative differences between the groups. The minimal clinically important difference in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score was defined as 7.5 points. Results. There were no clinically or statistically significant differences between the knee-specific measures (WOMAC, Oxford Knee Score (OKS), Forgotten Joint Score (FJS)) or HRQoL measures (EuroQol five-dimension questionnaire (EQ-5D) and EuroQol visual analogue scale (EQ-VAS)) at 12 months between the groups. However, the rTKA group had significantly (p = 0.029) greater improvements in the WOMAC pain component (mean difference 9.7, 95% confidence interval (CI) 1.0 to 18.4) over the postoperative period (two, six, and 12 months), which was clinically meaningful. This was not observed for function (p = 0.248) or total (p = 0.147) WOMAC scores. The rTKA group was significantly (p = 0.039) more likely to have expectation of ‘Relief of daytime pain in the joint’ when compared with the mTKA group. There were no other significant differences in expectations met between the groups. There was no significant difference in patient satisfaction with their knee (p = 0.464), return to work (p = 0.464), activities (p = 0.293), or pain (p = 0.701). Conclusion. Patients undergoing rTKA had a clinically meaningful greater improvement in their knee pain over the first 12 months, and were more likely to have fulfilment of their expectation of daytime pain relief compared with patients undergoing mTKA. However, rTKA was not associated with a clinically significant greater knee-specific function or HRQoL, according to current definitions. Cite this article: Bone Joint J 2024;106-B(5):450–459

Aims. While patients with psychological distress have poorer short-term outcomes after total knee arthroplasty (TKA), their longer-term function is unknown. We aimed to 1) assess the influence of preoperative mental health status on long-term functional outcomes, quality of life, and patient satisfaction; and 2) analyze the change in mental health after TKA, in a cohort of patients with no history of mental health disorder, with a minimum of ten years’ follow-up. Methods. Prospectively collected data of 122 patients undergoing primary unilateral TKA in 2006 were reviewed. Patients were assessed pre- and postoperatively at two and ten years using the Knee Society Knee Score (KSKS) and Function Score (KSFS); Oxford Knee Score (OKS); and the Mental (MCS) and Physical Component Summary (PCS) which were derived from the 36-Item Short-Form Health Survey questionnaire (SF-36). Patients were stratified into those with psychological distress (MCS < 50, n = 51) and those without (MCS ≥ 50, n = 71). Multiple regression was used to control for age, sex, BMI, Charlson Comorbidity Index (CCI), and baseline scores. The rate of expectation fulfilment and satisfaction was compared between patients with low and high MCS. Results. There was no difference in the mean KSKS, KSFS, OKS, and SF-36 PCS at two years or ten years after TKA. Equal proportions of patients in each group attained the minimal clinically important difference for each score. Psychologically distressed patients had a comparable rate of satisfaction (91.8% (47/51) vs 97.1% (69/71); p = 0.193) and fulfilment of expectations (89.8% vs 97.1%; p = 0.094). The proportion of distressed patients declined from 41.8% preoperatively to 29.8% at final follow-up (p = 0.021), and their mean SF-36 MCS improved by 10.4 points (p < 0.001). Conclusion. Patients with poor mental health undergoing TKA may experience long-term improvements in function and quality of life that are comparable to those experienced by their non-distressed counterparts. These patients also achieved a similar rate of satisfaction and expectation fulfilment. Undergoing TKA was associated with improvements in mental health in distressed patients, although this effect may be due to residual confounding. Cite this article: Bone Joint J 2020;102-B(7):845–851

We aimed to document the pre-operative expectations in Korean patients undergoing total knee replacement using an established survey form and to determine whether expectations were influenced by sociodemographic factors or pre-operative functional status. Expectations regarding 17 items in the Knee Replacement Expectation Survey form were investigated in 454 patients scheduled for total knee replacement. The levels and distribution patterns of summated expectation and of five expectation categories (relief from pain, baseline activity, high flexion activity, social activity and psychological well-being) constructed from the 17 items were assessed. Univariate analyses and multivariate logistic regression were performed to examine the associations of expectations with the sociodemographic factors and the functional status. The top three expectations were relief from pain, restoration of walking ability, and psychological well-being. Of the five expectation categories, relief from pain was ranked the highest, followed by psychological well-being, restoration of baseline activity, ability to perform high flexion activities and ability to participate in social activities. An age of < 65 years, being employed, a high Western Ontario and McMaster Universities osteoarthritis index function score and a low Short-form 36 social score were found to be significantly associated with higher overall expectations

Abstract. Aims. Whilst short and mid-term activity levels after a Total Knee Replacement (TKR) have been reported in the literature; there is an over simplification of the reporting and longer-term activity levels are unknown. The aim of this study was to map the long-term trajectories of patients’ physical activity levels postoperatively to identify meaningful subgroups and explore associations with preoperative variables. Methods. This was a secondary analysis of a single centre longitudinal cohortstudy using group-based trajectory modelling (GBTM) of the University of California, Los Angeles (UCLA) physical activity score over ten years. Multinomial logistic regression models (both adjusted and unadjusted) were used to test associations between preoperative variables and trajectory group membership. Results. 266 of the 904 eligible patients were recruited (29%). Data from 260 patients was available for analysis. Four trajectory groups were identified with good fit of the model (average posterior probability 0.79 to 0.93). Of the four groups, the two more active groups had a peak activity level between two-three years postoperatively; the less active groups had a peak activity level at between three months and one year. Preoperative UCLA, participation in sports in the three years prior to surgery and male gender showed trends towards association with a higher activity group. Conclusions. Four trajectory groups were identified giving a more detailed understanding of temporal trends in physical activity levels post TKR. There was weak evidence to show an association between patient expectation, preoperative UCLA score and participation in sports in the prior three years and group membership

We explored the outcome of staged bilateral total knee replacement (TKR) for symmetrical degenerative joint disease and deformity in terms of patient expectations, functional outcome and satisfaction. From 2009 to 2011, 70 consecutive patients (41 female) with a mean age of 71.7 years (43 to 89) underwent 140 staged bilateral TKRs at our institution, with a mean time between operations of 7.8 months (2 to 25). Patients were assessed pre-operatively and at six and 12 months post-operatively using the Short Form-12, Oxford knee score (OKS), expectation questionnaire and satisfaction score. The pre-operative OKS was significantly worse before the first TKR (TKR1), but displayed significantly greater improvement than that observed after the second TKR (TKR2). Expectation level increased from TKR1 to TKR2 in 17% and decreased in 20%. Expectations of pain relief and stair-climbing were less before TKR2; in contrast, expectations of sporting and social activities were greater. Decreased expectations of TKR2 were significantly associated with younger age and high expectations before TKR1. Patient satisfaction was high for both TKR1 (93%) and TKR2 (87%) but did not correlate significantly within individuals. We concluded that satisfaction with one TKR does not necessarily translate to satisfaction following the second. . Cite this article: Bone Joint J 2014;96-B:752–8

Introduction. Robotic-arm total knee arthroplasty (RTKA) was developed to potentially improve accuracy of bone cuts, component alignment, soft tissue balance, and patient outcomes. There is a paucity of data demonstrating that RTKA is superior to conventional total knee arthroplasty (CTKA) in terms of any of these metrics. This prospective comparative multicenter study was designed with these purposes in mind. Methods. Patients were enrolled between June 1st, 2016 and March 31st, 2018 in a prospective, non-randomized, open-label, multicenter, consecutive comparative cohort study comparing RTKA and CTKA. Only patients who satisfied the following inclusion criteria were included: body mass index (BMI) ≤ 40kg/m2, primary unilateral TKA procedure, at least 18 years of age, and no joint infection. The following data were collected for analysis:. Preoperative data on component size prediction from CT scans. Intraoperative data on bone resection levels and joint line maintenance. Functional activity scores, patient-reported symptoms, satisfaction and expectation scores using The New Knee Society Scoring System. Radiographic results, specifically coronal alignment. Results. For femoral components implanted, 82% were the exact size as predicted by the robotic-software and the remaining 18% were within 1 size (100% within 1 size). For tibial implants, 69% were the exact size of what the robotic-software predicted and 29% were within 1 size (98% within 1 size). RTKAs had significantly less distal lateral femoral resection (5.55 vs. 7.11 mm), distal medial femoral resection (6.89 vs. 7.97 mm), lateral tibial resection (7.76 vs. 8.54 mm), and medial tibial resection (4.11 vs. 5.56 mm, p<0.05) compared to CTKA. Joint line restoration was comparable between RTKA and CTKA, but required less tibial bone removal when using robotic techniques. Pre-operatively, all demographic, functional, symptom, satisfaction, and expectation measures were similar between treatment groups (all p<0.05, Tables 1–5). Those who underwent RTKA had significantly higher mean functional activity walking and standing score improvements from baseline to 4–6 weeks (1.4 vs. −1.2 points; p=0.019) and to 6 months (9.6 vs. 6.9 points; p=0.017) after surgery compared to CTKA. The mean overall functional activity score improvement from baseline to 1-year post-surgery was also higher for RTKA compared to CTKA (36.8 vs. 15.0 points; p=0.020). For all other parameters (standard activities, advanced activities, pain with walking, pain with stairs, satisfaction and expectation scores), score changes from baseline were not significantly different between groups, though many trended slightly higher for RTKA. Radiographic evaluation of RTKA demonstrated that varus deformity was corrected to neutral in 96% of cases and valgus deformity was corrected in 100%. Conclusion. To the best of our knowledge, this is the first study to prospectively evaluate outcomes of RTKA patients compared to CTKA. A number of positive early effects were seen with RTKA. This patient cohort will continue to be followed, and these findings may translate into longer-term patient reported outcomes improvement, longer component survivorship and cost savings. For any figures or tables, please contact authors directly

Introduction. In November 2017, the Center for Medicare and Medicaid Services (CMS) finalized the 2018 Medicare Outpatient Prospective Payment System rule that removed total knee arthroplasty (TKA) procedures from the Medicare inpatient-only (IPO) list of procedures. This action had significant and unexpected consequences. For several years, CMS has utilized a rule called the “Two-Midnight Rule” to define outpatient status for all procedures not on the IPO list. CMS made TKA subject to the “Two-Midnight Rule” in conjunction with the decision to move TKA off the IPO list. According to the “Two-Midnight Rule,” a hospital admission should be expected to span at least two midnights in order to be covered as an inpatient procedure. If it can be reliably expected that the patient will not require at least two midnights in the hospital, the “Two-Midnight Rule” suggests that the patient is considered an outpatient and is therefore subject to outpatient payment policies. Under prior guidance related to the “Two-Midnight Rule;” however, CMS also states that Medicare may treat some admissions spanning less than two midnights as inpatient procedures if the patient record contains documentation of medical need. The final rule was clear in stating CMS's expectation was that the great majority of TKAs would continue to be provided in an inpatient setting. Methods. We looked at 3 different levels of the IPO rule impact on TKA for Medicare beneficiaries: a national comparison of fee for service (FFS) inpatient and outpatient classification for 2017 vs 2018; a survey of AAHKS surgeons completed in April of 2019; and an in-depth analysis of a large academic medical center experience. An analysis of change in inpatient classification of TKA patients over time, number of Quality Improvement Organization (QIO) audits, compliance solutions of organizations for the new rule and cost implications of those compliance solutions were evaluated. Results. Hospital reimbursement averages $10,122 in an outpatient facility (includes implant, other supplies, ancillary staff, etc.) but does NOT include the physician payment. Average hospital reimbursement in the inpatient setting is $11,760. The difference in reimbursement to hospitals varies widely however due to nuances in the CMS reimbursement formula (90. th. percentile decrease, $6,725 vs 10th percentile $2,048). Physician payments are the same in both settings (avg $1,403). TKA patients not designated for in-patient admissions are not eligible for bundle payment programs thus removing the healthiest, most predictable patients from the program. Patients designated as outpatients are subject to higher out of pocket expenses. Patients may have an annual Medicare Part B Deductible ($185) and a 20% copay as well as prescription and durable medical equipment costs. A survey of AAHKS surgeons demonstrated that 44.74% were doing inpatient designation only, 17.89% were doing outpatient designation only, 25.53 % designated patients as necessary, and 10% were designated by the hospital. This survey showed that 66/374 (17.65%) of AAHKS responders had undergone a QIO audit as a result of issues with the IPO rule. An evaluation of a large academic medical center demonstrated that since January 1, 2018, 470/690 (68.1%) of CMS TKA patients left the institution in less than 2 midnights. During this time period the institution was subjected to 2 QIO audits. All CMS patients had been designated as inpatients prior to May 2019. Conclusions. There are many unintended consequences to the IPO rule application to TKA. Clearly, more study is needed to provide better guidelines to knee replacement surgeons. A well-defined outpatient TKA bundle would allow CMS and TKA surgeons to better serve their patients. For figures, tables, or references, please contact authors directly

Introduction. Despite the demonstrated success of total knee arthroplasty (TKA) and higher rates of arthritis and disability from arthritis among minorities, these populations utilize TKA at lower rates than non-Hispanic white patients in the United States. In addition, women present for TKA with more advanced disease prior to TKA than their male counterparts. In order to explore potential reasons for this, we examined the relationship between race, gender, and pre-operative expectations on postoperative outcomes among patients undergoing TKA. Methods. 134 patients scheduled for primary unilateral TKA secondary to moderate to severe osteoarthritis were enrolled in this two-institution prospective study. All patient demographics were collected and recorded in an electronic data registry. In addition, patient reported outcome (PRO) questionnaires, including the Knee Injury and Osteoarthritis Outcome Score (KOOS), HSS Patient Expectation Questionnaire, Social Support Survey, Pain Catastrophizing Scale, Visual Analogue Pain Scale (VAS), Geriatric Depression Scale and European Quality (EQ) of Life 5-Dimensions with EQ VAS were prospectively collected at 4 time points (baseline, 4–8 weeks, 9–14 months, 20–26 months postoperative). Statistical analysis was then conducted among patients of different gender and ethnic background to assess for the effect of these demographic variables on patient expectations and outcomes. Results. Female sex was associated with worse preoperative KOOS scores in symptoms (p=0.021), pain (p=0.019), and activities of daily living (p=0.020). African American race was associated with worse preoperative KOOS scores in pain (p=0.009), activities of daily living (ADLs) (p=0.004), and quality of life (QOL) (p=0.003). However, despite worse pre-operative scores, no statistically significant differences were noted in the aforementioned categories between the groups at any point post-operatively. Conclusion. Our results indicate that female and African American patients undergoing TKA presented with worse pre-operative KOOS scores compared with white male patients. However, outcomes were good among all groups postoperatively, and neither race nor gender was associated with compromised post-operative outcomes in relation to pain, ADLs or QOL. These findings may be valuable in counseling patients and surgeons regarding the value of increase utilization of TKA in these patient populations. Further study is necessary to better understand the lower utilization or later presentation observed in these populations

Aims

A novel enhanced cement fixation (EF) tibial implant with deeper cement pockets and a more roughened bonding surface was released to market for an existing total knee arthroplasty (TKA) system.This randomized controlled trial assessed fixation of the both the EF (ATTUNE S+) and standard (Std; ATTUNE S) using radiostereometric analysis.

Purpose. Patient expectations of total knee arthroplasty (TKA) can be managed through education. E-learning is the application of information technology to education. Providing information to patients at the place and time of their choosing, e-learning has the potential to broaden the reach of existing services for patients. This study evaluated whether an e-learning tool could affect whether patients felt their expectations were met and whether they were satisfied with surgery one year following primary TKA. Method. We recruited consecutive patients with osteoarthritis and randomized them to either standard patient education (n=207), or to our standard patient education plus a new e-learning tool (n=209). Preoperative measures were completed following the patients’ Pre-Admission clinic (PAC) visit and prior to accessing the e-learning tool. Postoperative patient reported outcome measures (PROMs) were completed at six weeks, three months and one year after TKA. We used the Postoperative Expectation Questionnaire to measure the degree to which patient expectations had been met and the Patient Acceptable Symptom State (PASS) question to measure patient satisfaction at one year postoperative. We collected several PROMs for descriptive purposes including: new Knee Society Knee Scoring System (KSS); (Pre-Op and Post-Op versions), Knee injury and Osteoarthritis Outcome Score (KOOS), the Medical Outcomes Study 12-Item Short Form Health Survey, version 2 (SF-12), Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS), University of California at Los Angeles (UCLA) Activity Score, and the Social Role Participation Questionnaire (SRPQ). Results. Both groups were similar with respect to their preoperative PROMs. Preoperative patient satisfaction was low, with few patients satisfied with their present state prior to TKA and similar between groups (14% intervention group, 11% control group). At one year postoperatively, the risk that expectations of patients were not met was 21.8% in the control group and 21.4% in the intervention group for a risk difference of 1.3% (95% CI −7.8% to 10.4%, p = 0.78). The proportion of patients satisfied with their TKA at one year postoperative was similar in the intervention group 78.6% and the control group 78.2%, and the risk difference 0.6% (95% CI −8.4% to 9.6%) was not statistically significant (p = 0.78). At one year postoperative we found significant postoperative between-group differences in favour of the control group for the new KSS symptoms score and the functional activities score. We also found that control patients had less anxiety, lower scores for rumination, magnification, and helplessness than intervention patients on the PCS. Conclusion. Patients randomized to the e-learning tool had significantly better KSS symptom scores and functional activities scores as well as lower anxiety and helplessness scores but they did not have a reduced risk of expectations not being met or an improved overall satisfaction with their TKA

Aims

With up to 40% of patients having patellofemoral joint osteoarthritis (PFJ OA), the two arthroplasty options are to replace solely the patellofemoral joint via patellofemoral arthroplasty (PFA), or the entire knee via total knee arthroplasty (TKA). The aim of this study was to assess postoperative success of second-generation PFAs compared to TKAs for patients treated for PFJ OA using patient-reported outcome measures (PROMs) and domains deemed important by patients following a patient and public involvement meeting.

Aims

The primary objective of this registry-based study was to compare patient-reported outcomes of cementless and cemented medial unicompartmental knee arthroplasty (UKA) during the first postoperative year. The secondary objective was to assess one- and three-year implant survival of both fixation techniques.

Satisfaction is increasingly employed as an outcome measure for a successful total knee replacement (TKR). Satisfaction as an outcome measure encompasses many different intrinsic and extrinsic factors related to a person’s experience before and after TKR. The Swedish Knee Arthroplasty Registry has previously demonstrated on a large population study that 17% of TKR recipients are not satisfied with their TKR outcome. This finding has been replicated in other countries. Similar significant factors emerged from these registry studies that are related to satisfaction. It would appear that satisfaction is better after more chronic diseases and whether the TKR results in pain relief or improved function. Importantly, unmet pre-operative expectations are a significant predictor for dissatisfaction following a TKR. It may be possible to improve rates by addressing the issues surrounding pain, function and expectation before embarking on surgery. Cite this article: Bone Joint J 2013;95-B, Supple A:148–52

Aims

The aims of this study were to investigate the ability to kneel after total knee arthroplasty (TKA) without patellar resurfacing, and its effect on patient-reported outcome measures (PROMs). Secondary aims included identifying which kneeling positions were most important to patients, and the influence of radiological parameters on the ability to kneel before and after TKA.

Introduction. The Signature system has been hailed as a new way to perform arthroplasty of the knee. It combines the accuracy in restoring mechanical axes of navigation with the convenience and familiarity of classical surgical techniques. With this comes the expectation that they should produce better functional results. In the literature, thus far, there is little data to corroborate this. The aim of this paper is to compare the early functional outcomes of this with the cemented AGC knee replacement system. Methods. Since April 2010, based on requirement, 25 patients underwent Signature knee replacements during this period for symptomatic degenerative or inflammatory arthritis with varying levels of deformity. Oxford functional scores were taken pre-operatively, at 6 weeks, 3 months and 6 months. These were then matched to an equal number of patients that had undergone an AGC knee replacement by the same surgeon. They were matched by pre-operative functional Oxford scores, age and gender. Results. The mean age for our patients was 63.4 years at the time of surgery. The mean follow-up period was 6.9 months. There have been no revision procedures required or complications in either group so far. The mean pre-operative Oxford score was 44.4, 26.3, 25 and 19 pre-operatively, at 6 weeks, 3 months and 6 months respectively for the Signature knee group. No link was seen between pre-operative function and post-operative scores. The AGC group has had comparable results thus far at scores 43.2, 28.4, 20.1 and 19.7 respectively. More results are to follow. Conclusions. To our knowledge this is one of the earliest reports of functional results following the new technique of knee mechanical axis restoration for arthroplasty surgery. The system showed comparable results at similar post-operative time periods with the conventionally performed AGC knee replacement system

Aims

Neither a surgeon’s intraoperative impression nor the parameters of computer navigation have been shown to be predictive of the outcomes following total knee arthroplasty (TKA). The aim of this study was to determine whether a surgeon, with robotic assistance, can predict the outcome as assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain (KPS), one year postoperatively, and establish what factors correlate with poor KOOS scores in a well-aligned and balanced TKA.

Aims

The aim of this study was to measure the effect of hospital case volume on the survival of revision total knee arthroplasty (RTKA).