Assessing the Viability of the EQ-5D as Part of a Battery of Outcomes in Elderly Total Knee Arthroplasty Patients: A Comparison of Generic, Condition-Specific, and Preference-Based Patient-Reported Outcome Measures

Background In the current economic climate it has become increasingly important to evaluate the effectiveness of expensive procedures such as total knee arthroplasties (TKAs). Patient-reported outcome measures, such as generic and condition-specific profile measures, are popular ways of determining outcomes. However, these cannot be used reliably for the purpose of economic evaluations. The EQ-5D, designed for cost-utility analysis, could offer potential advantages to outcome measurement; however, little is known about the viability and performance of this measure in more elderly (_ 75 years) patient cohorts. Aims The aim of this study was to assess the viability of the EQ-5D for use in the evaluation of TKA and to provide justification for its continued inclusion in the clinical audit of patients undergoing arthroplasty in a large general hospital. Methods Seven-hundred and seventy-nine consecutive patients undergoing TKA participated in this study. Self-report audit questionnaire booklets were administered at baseline (during a pre-admission clinic appointment) and six months post-operatively (postally). Booklets comprised of the Oxford Knee Scale (OKS;), 12-dimension Short Form (SF-12;), and the EQ-5D (). Results Two-hundred and forty-six subjects completed both the baseline and follow-up audit surveys. Correlations were strongest between the EQ-5D and OKS instruments (baseline: Tb=-0.58; p0.01; follow-up: Tb=-0.41; p0.01),.. The EQ-5D displayed large effect sizes (d=0.94) and was able to detect clinically important HRQoL improvements (ROC P-value=0.65; CI0.08; p0.001), discriminate those patients who were experiencing poorer pre-operative health (p0.001), and detect those who deteriorated post-operatively (p0.001). Adequate reliability (Cronbach's =0.79) of the EQ-5D instrument was seen post-operatively as well. Conclusions Results from this study reveal that the EQ-5D instrument shows good responsiveness to health changes in elderly TKA patients post-operatively. Its correlations with the OKS, detection of poorer pre-operative health, and detection of deterioration post-operatively also suggest good validity for the EQ-5D in this cohort. Finally, the relatively large reliability statistic post-operatively supports the use of the EQ-5D in audits. Together, these findings support the continued use of the EQ-5D instrument in future arthroplasty audits and provide evidence that it is viable for the use in cost-utility analysis.sch_phyunpub2424unpu

Discovery of a Wolf-Rayet Star Through Detection of its Photometric Variability

We report the serendipitous discovery of a heavily reddened Wolf-Rayet star that we name WR142b. While photometrically monitoring a cataclysmic variable, we detected weak variability in a nearby field star. Low-resolution spectroscopy revealed a strong emission line at 7100 Ang., suggesting an unusual object and prompting further study. A spectrum taken with the Hobby-Eberly Telescope confirms strong HeII emission and a NIV 7112 Ang. line consistent with a nitrogen-rich Wolf-Rayet star of spectral class WN6. Analysis of the HeII line strengths reveals no detectable hydrogen in WR142b. A blue-sensitive spectrum obtained with the Large Binocular Telescope shows no evidence for a hot companion star. The continuum shape and emission line ratios imply a reddening of E(B-V)=2.2 to 2.5 mag. If not for the dust extinction, this new Wolf-Rayet star could be visible to the naked eye.Comment: 15 pages, 6 figures, submitted to the Astronomical Journa

The effect of COVID-19 restrictions on rehabilitation and functional outcome following total hip and knee arthroplasty during the first wave of the pandemic

Aims: The primary aim was to assess the patient-perceived effect of restrictions imposed due to COVID-19 on rehabilitation following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Secondary aims were to assess perceived restrictions, influence on mental health, and functional outcome compared to patients undergoing surgery without restriction. Methods: During February and March 2020, 105 patients underwent THA (n = 48) or TKA (n = 57) and completed preoperative and six-month postoperative assessments. A cohort of 415 patients undergoing surgery in 2019 were used as the control. Patient demographic data, BMI, comorbidities, Oxford Hip Score (OHS) or Knee Score (OKS), and EuroQoL five-domain (EQ-5D) score were collected preoperatively and at six months postoperatively. At six months postoperatively, the 2020 patients were also asked to complete a questionnaire relating to the effect of the social restrictions on their outcome and their mental health. Results: Nearly half of the patients (47.6%, n = 50/105) felt that the restrictions imposed by COVID-19 had limited their rehabilitation and were associated with a significantly worse postoperative OKS (p < 0.001), EQ-5D score (p < 0.001), and lower satisfaction rate (p = 0.019). The reasons for the perceived limited rehabilitation were: being unable to exercise (n = 32, 64%), limited access to physiotherapy (n = 30, 60%), and no face-to-face follow-up (n = 30, 60%). A quarter (n = 26) felt that their mental health had deteriorated postoperatively; 17.1% (n = 18) felt depressed and 26.7% (n = 28) felt anxious. Joint-specific scores and satisfaction for the 2020 group were no different to the 2019 group, however patients undergoing THA in 2020 had a significantly worse postoperative EQ-5D compared to the 2019 cohort (difference 0.106; p = 0.001) which was not observed in patients undergoing TKA. Conclusion: Half of the 2020 cohort felt that their rehabilitation had been limited and was associated with worse postoperative Oxford and EQ-5D scores, and lower rates of patient satisfaction, but relative to the 2019 cohort their overall outcomes were no different, with the exception of THA patients who had a worse general health score. Level of evidence: Prospective study, Level 2

Physical function following TKA compared to age matched healthy controls

Purpose: to explore whether physical and functional impairments exist in those who have undergone primary TKA compared to age matched healthy controls. Relevance: Many studies have suggested that although function generally improves following TKA, patients continue to experience significant functional limitations. Most of these studies however have assessed function using self-reported measures despite recommendations that both self-report and performance based measures are required to capture the full spectrum of functional ability. Furthermore, there have been no recent studies that have comprehensively compared outcomes in TKA with those who have no knee related pathology. Therefore, the evidence to suggest that functional limitations persist cannot be considered as robust. Participants: A group of patients (n = 15) were recruited who had undergone primary TKA for osteoarthritis between 10 and 14 months previously (median age = 71 years). A group of age matched health controls (n = 12, median age = 69.5 years) were recruited from local community groups. Methods: Self reported function (0-100 scale where 0 is best), timed-up-and-go, stair ascent/descent, walking speed, leg extensor power and range of motion were compared between groups. Analysis: Mann-Whitney U-tests were used to detect inter-group differences. The alpha level was set at 0.05. Results: Maximum flexion in the TKA group (median = 110o) was significantly less (p = 0.002) than the control group (median = 120o). The TKA group reported significantly worse function (median scores TKA = 10.0, control = 0.00, p = 0.028). No significant differences (p &gt;0.05) however were found between groups in any of the performance based measures of function (timed up and go, timed stair ascent/descent, walking speed) or in knee extensor strength. Conclusions: although individuals with TKA perceived their functional ability to be significantly worse than their healthy counterparts, there was no evidence to suggest that significant functional impairments existed in this small group. Implications: expectations of outcome in TKA have been shown to be an important factor in overall patient satisfaction with their surgery. The results of this study could help to provide improved information regarding functional ability following TKA.sch_phyunpub2310unpu

Standard versus short stem cemented Exeter^® when used for primary total hip arthroplasty:a survivorship analysis

Aims: The aims were to compare the survival of the cemented standard (150 mm) with the short (DDH [35.5 mm offset or less], number 1 short stem [125 mm options of 37.5 mm, 44 mm, 50 mm offset] and revision [44/00/125]) Exeter ® V40 femoral stems when used for primary total hip arthroplasty (THA). Methods: Patients were retrospectively identified from an arthroplasty database. A total of 664 short stem Exeter ® variants were identified, of which 229 were DDH stems, 208 number 1 stems and 227 revision stems were implanted between 2011 and 2020. A control group of 698 standard Exeter ® stems used for THA was set up, and were followed up for a minimum of 10 years follow-up (implanted 2011). All-cause survival was assessed for THA and for the stem only. Adjusted analysis was undertaken for age, sex and ASA grade. Results: The median survival time for the short stems varied according to design: DDH had a survival time of 6.7 years, number 1 stems 4.1 years, and revision stems 7.2 years. Subjects in the short stem group (n = 664) were significantly younger (mean difference 5.1, P &lt; 0.001) and were more likely to be female (odds ratio 1.89, 95% CI 1.50 to 2.39, P &lt; 0.001), compared to the standard group. There were no differences in THA (P = 0.26) or stem (P = 0.35) survival at 5 years (adjusted THA: 98.3% vs. 97.2%; stem 98.7% vs. 97.8%) or 10 years (adjusted THA 97.0% vs. 96.0 %; stem 96.7% vs. 96.2%) between standard and short stem groups, respectively. At 5 years no differences were found in THA (DDH: 96.7%, number 1 97.5%, revision 97.3%, standard 98.6%) or stem (DDH: 97.6%, number 1 99.0%, revision 97.3%, standard 98.2%) survival between/among the different short stems or when compared to the standard group. Conclusion: The Exeter ® short stems offer equivocal survival when compared to the standard stem at 5- to 10-year follow-up, which does not seem to be influenced by the short stem design.</p

Meaningful values in the Forgotten Joint Score after total knee arthroplasty: minimal clinical important difference, minimal important and detectable changes, and patient-acceptable symptom state

AimsThe aim of this study was to identify the minimal clinically important difference (MCID), minimal important change (MIC), minimal detectable change (MDC), and patient-acceptable symptom state (PASS) threshold in the Forgotten Joint Score (FJS) according to patient satisfaction six months following total knee arthroplasty (TKA).MethodsDuring a one-year period 484 patients underwent a primary TKA and completed preoperative and six-month FJS and OKS. At six months patients were asked, “How satisfied are you with your operated knee?” Their response was recorded as: very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied. The difference between patients recording neutral (n = 44) and satisfied (n = 153) was used to define the MCID. MIC for a cohort was defined as the change in the FJS for those patients declaring their outcome as satisfied, whereas receiver operating characteristic curve analysis was used to determine the MIC for an individual and the PASS threshold. Distribution-based methodology was used to calculate the MDC.ResultsUsing satisfaction as the anchor question, the MCID for the FJS was 16.6 (95% confidence interval (CIs) 8.9 to 24.3; p < 0.001) and when adjusting for confounding this decreased to 13.7 points (95% CI 4.8 to 22.5; p < 0.001). The MIC for the FJS for a cohort of patients was 17.7 points and for an individual patient was 10 points. The MDC90 for the FGS was 12 points; where 90% of patients scoring more than this will have experienced a real change that is beyond measurement error. The PASS was defined as 22 points or more in the postoperative FJS.ConclusionThe estimates for MCID and MIC can be used to assess whether there is clinical difference between two groups and whether a cohort/patient has had a meaningful change in their FJS, respectively. The MDC90 of 12 points suggests a value lower than this may fall within measurement error. A postoperative FJS of 22 or more was predictive of achieving PASS