ORCID Profile
0000-0001-6069-978X
Current Organisation
University of Oxford
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Publisher: British Editorial Society of Bone & Joint Surgery
Date: 10-2016
DOI: 10.1302/0301-620X.98B10.BJJ-2016-0483.R1
Abstract: The aim of this to study was to compare the previously unreported long-term survival outcome of the Oxford medial unicompartmental knee arthroplasty (UKA) performed by trainee surgeons and consultants. We therefore identified a previously unreported cohort of 1084 knees in 947 patients who had a UKA inserted for anteromedial knee arthritis by consultants and surgeons in training, at a tertiary arthroplasty centre and performed survival analysis on the group with revision as the endpoint. The ten-year cumulative survival rate for revision or exchange of any part of the prosthetic components was 93.2% (95% confidence interval (CI) 86.1 to 100, number at risk 45). Consultant surgeons had a nine-year cumulative survival rate of 93.9% (95% CI 90.2 to 97.6, number at risk 16). Trainee surgeons had a cumulative nine-year survival rate of 93.0% (95% CI 90.3 to 95.7, number at risk 35). Although there was no differences in implant survival between consultants and trainees (p = 0.30), there was a difference in failure pattern whereby all re-operations performed for bearing dislocation (n = 7), occurred in the trainee group. This accounted for 0.6% of the entire cohort and 15% of the re-operations. This is the largest single series of the Oxford UKA ever reported and demonstrates that good results can be achieved by a heterogeneous group of surgeons, including trainees, if performed within a high-volume centre with considerable experience with the procedure. Cite this article: Bone Joint J 2016 (10 Suppl B):22–7.
Publisher: Springer Science and Business Media LLC
Date: 08-2023
DOI: 10.1186/S13643-023-02290-6
Abstract: The aim of this systematic review was to summarise the evidence for the clinical effectiveness of revision knee arthroplasty (rKA) compared to non-operative treatment for the management of patients with elective, aseptic causes for a failed knee arthroplasty. MEDLINE, Embase, AMED and PsychINFO were searched from inception to 1st December 2020 for studies on patients considering elective, aseptic rKA. Patient-relevant outcomes (PROs) were defined as implant survivorship, joint function, quality of life (QoL), complications and hospital admission impact. No studies compared elective, aseptic rKA to non-operative management. Forty uncontrolled studies reported on PROs following elective, aseptic rKA (434434 rKA). Pooled estimates for implant survivorship were: 95.5% (95% CI 93.2–97.7%) at 1 year [seven studies (5524 rKA)], 90.8% (95% CI 87.6–94.0%) at 5 years [13 studies (5754 rKA)], 87.4% (95% CI 81.7–93.1%) at 10 years [nine studies (2188 rKA)], and 83.2% (95% CI 76.7–89.7%) at 15 years [two studies (452 rKA)]. Twelve studies (2382 rKA) reported joint function and/or QoL: all found large improvements from baseline to follow-up. Mortality rates were low (0.16% to 2% within 1 year) [four studies (353064 rKA)]. Post-operative complications were common (9.1 to 37.2% at 90 days). Higher-quality evidence is needed to support patients with decision-making in elective, aseptic rKA. This should include studies comparing operative and non-operative management. Implant survivorship following elective, aseptic rKA was ~ 96% at 1 year, ~ 91% at 5 years and ~ 87% at 10 years. Early complications were common after elective, aseptic rKA and the rates summarised here can be shared with patients during informed consent. PROSPERO CRD42020196922
Publisher: British Editorial Society of Bone & Joint Surgery
Date: 04-2021
DOI: 10.1302/0301-620X.103B4.BJJ-2020-1560.R1
Abstract: To estimate the measurement properties for the Oxford Knee Score (OKS) in patients undergoing revision knee arthroplasty (responsiveness, minimal detectable change (MDC-90), minimal important change (MIC), minimal important difference (MID), internal consistency, construct validity, and interpretability). Secondary data analysis was performed for 10,727 patients undergoing revision knee arthroplasty between 2013 to 2019 using a UK national patient-reported outcome measure (PROM) dataset. Outcome data were collected before revision and at six months postoperatively, using the OKS and EuroQol five-dimension score (EQ-5D). Measurement properties were assessed according to COnsensus-based Standards for the selection of health status Measurement Instruments (COSMIN) guidelines. A total of 9,219 patients had complete outcome data. Mean preoperative OKS was 16.7 points (SD 8.1), mean postoperative OKS 29.1 (SD 11.4), and mean change in OKS + 12.5 (SD 10.7). Median preoperative EQ-5D index was 0.260 (interquartile range (IQR) 0.055 to 0.691), median postoperative EQ-5D index 0.691 (IQR 0.516 to 0.796), and median change in EQ-5D index + 0.240 (IQR 0.000 to 0.567). Internal consistency was good with Cronbach’s α 0.88 (baseline) and 0.94 (post-revision). Construct validity found a high correlation of OKS total score with EQ-5D index ( r = 0.76 (baseline), r = 0.83 (post-revision), p 0.001). The OKS was responsive with standardized effect size (SES) 1.54 (95% confidence interval (CI) 1.51 to 1.57), compared to SES 0.83 (0.81 to 0.86) for the EQ-5D index. The MIC for the OKS was 7.5 points (95% CI 5.5 to 8.5) based on the optimal cut-off with specificity 0.72, sensitivity 0.60, and area under the curve 0.66. The MID for the OKS was 5.2 points. The MDC-90 was 3.9 points. The OKS did not demonstrate significant floor or ceiling effects. This study found that the OKS was a useful and valid instrument for assessment of outcome following revision knee arthroplasty. The OKS was responsive to change and demonstrated good measurement properties. Cite this article: Bone Joint J 2021 -B(4):627–634.
Publisher: Elsevier BV
Date: 09-2020
Publisher: Springer Science and Business Media LLC
Date: 17-12-2019
DOI: 10.1007/S11136-019-02381-9
Abstract: For patients with end-stage knee osteoarthritis, joint replacement is a widely used and successful operation to help improve quality-of-life when non-operative measures have failed. For a significant proportion of patients there is a choice between a partial or total knee replacement. Decision aids can help people weigh up the need for and benefits of treatment against possible risks and side-effects. This study explored patients’ experiences of deciding to undergo knee replacement surgery to identify information priorities, to inform a knee replacement decision aid. Four focus groups were held with 31 patients who were candidates for both partial and total knee replacement surgery. Two focus groups included patients with no prior knee replacement surgery (pre-surgery) two with patients with one knee already replaced and who were candidates for a second surgery on their other knee (post-surgery). Data were analysed using Framework Analysis. Participants described a process of arriving at ‘readiness for surgery’ a turning point where the need for treatment outweighed their concerns. Referral and personal factors influenced their decision-making and expectations of surgery in the hope to return to a former self. Those with previous knee surgery offered insights into whether their expectations were met. ‘Information for decisions’ details the practicality and the optimal timing for the delivery of a knee replacement decision aid. In particular, participants would have valued hearing about the experiences of other patients and seeing detailed pictures of both surgical options. Information priorities were identified to include in a decision aid for knee replacement surgery. Patients’ experiences of surgical decision-making have much in common with the Necessity-Concerns Framework. Whilst originally developed to understand drug treatment decisions and adherence, it provides a useful lens to understand decision-making about surgery. The use of a decision aid could enhance decision-making on knee replacement surgery. Ultimately, patients’ understanding of the risks and benefits of both surgical options could be improved and in turn, help informed decision-making. The knee replacement decision aid is perceived as a useful tool to be associated with other detailed information resources as recommended.
Publisher: Elsevier BV
Date: 11-2018
Publisher: Elsevier BV
Date: 03-2020
Publisher: BMJ
Date: 21-02-2019
DOI: 10.1136/BMJ.L352
Abstract: To present a clear and comprehensive summary of the published data on unicompartmental knee replacement (UKA) or total knee replacement (TKA), comparing domains of outcome that have been shown to be important to patients and clinicians to allow informed decision making. Systematic review using data from randomised controlled trials, nationwide databases or joint registries, and large cohort studies. Medline, Embase, Cochrane Controlled Register of Trials (CENTRAL), and Clinical Trials.gov, searched between 1 January 1997 and 31 December 2018. Studies published in the past 20 years, comparing outcomes of primary UKA with TKA in adult patients. Studies were excluded if they involved fewer than 50 participants, or if translation into English was not available. 60 eligible studies were separated into three methodological groups: seven publications from six randomised controlled trials, 17 national joint registries and national database studies, and 36 cohort studies. Results for each domain of outcome varied depending on the level of data, and findings were not always significant. Analysis of the three groups of studies showed significantly shorter hospital stays after UKA than after TKA (−1.20 days (95% confidence interval −1.67 to −0.73), −1.43 (−1.53 to −1.33), and −1.73 (−2.30 to −1.16), respectively). There was no significant difference in pain, based on patient reported outcome measures (PROMs), but significantly better functional PROM scores for UKA than for TKA in both non-trial groups (standard mean difference −0.58 (−0.88 to −0.27) and −0.29 (−0.46 to −0.11), respectively). Regarding major complications, trials and cohort studies had non-significant results, but mortality after TKA was significantly higher in registry and large database studies (risk ratio 0.27 (0.16 to 0.45)), as were venous thromboembolic events (0.39 (0.27 to 0.57)) and major cardiac events (0.22 (0.06 to 0.86)). Early reoperation for any reason was higher after TKA than after UKA, but revision rates at five years remained higher for UKA in all three study groups (risk ratio 5.95 (1.29 to 27.59), 2.50 (1.77 to 3.54), and 3.13 (1.89 to 5.17), respectively). TKA and UKA are both viable options for the treatment of isolated unicompartmental osteoarthritis. By directly comparing the two treatments, this study demonstrates better results for UKA in several outcome domains. However, the risk of revision surgery was lower for TKA. This information should be available to patients as part of the shared decision making process in choosing treatment options. PROSPERO number CRD42018089972.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 22-08-2023
Abstract: The purpose of this study was to investigate patient-relevant outcomes following first revision total knee arthroplasties (rTKAs) performed for different indications. This population-based cohort study utilized data from the United Kingdom National Joint Registry, Hospital Episode Statistics Admitted Patient Care, National Health Service Patient-Reported Outcome Measures, and the Civil Registrations of Death. Patients undergoing a first rTKA between January 1, 2009, and June 30, 2019, were included in our data set. Patient-relevant outcomes included implant survivorship (up to 11 years postoperatively), mortality and serious medical complications (up to 90 days postoperatively), and patient-reported outcome measures (at 6 months postoperatively). A total of 24,540 first rTKAs were analyzed. The patient population was 54% female and 62% White, with a mean age at the first rTKA of 69 years. At 2 years postoperatively, the cumulative incidence of re-revision surgery ranged from 2.7% (95% confidence interval [CI], 1.9% to 3.4%) following rTKA for progressive arthritis to 16.3% (95% CI, 15.2% to 17.4%) following rTKA for infection. The mortality rate at 90 days was highest following rTKA for fracture (3.6% [95% CI, 2.5% to 5.1%]) and for infection (1.8% [95% CI, 1.5% to 2.2%]) but was .5% for other indications. The rate of serious medical complications requiring hospital admission within 90 days was highest for patients treated for fracture (21.8% [95% CI, 17.9% to 26.3%]) or infection (12.5% [95% CI, 11.2% to 13.9%]) and was lowest for those treated for progressive arthritis (4.3% [95% CI, 3.3% to 5.5%]). Patients who underwent rTKA for stiffness or unexplained pain had some of the poorest postoperative joint function (mean Oxford Knee Score, 24 and 25 points, respectively) and had the lowest proportion of responders (48% and 55%, respectively). This study found large differences in patient-relevant outcomes among different indications for first rTKA. The rate of complications was highest following rTKA for fracture or infection. Although rTKA resulted in large improvements in joint function for most patients, those who underwent surgery for stiffness and unexplained pain had worse outcomes. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.
Publisher: Elsevier BV
Date: 12-2022
DOI: 10.1016/J.JOCA.2022.08.016
Abstract: To investigate trends in the incidence rate and the main indication for revision knee replacement (rKR) over the past 15 years in the UK. Repeated national cross-sectional study from 2006 to 2020 using data from the National Joint Registry (NJR). Crude incidence rates were calculated using population statistics from the Office for National Statistics. Annual total counts of rKR increased from 2,743 procedures in 2006 to 6,819 procedures in 2019 (149% increase). The incidence rate of rKR increased from 6.3 per 100,000 adults in 2006 (95% CI 6.1 to 6.5) to 14 per 100,000 adults in 2019 (95% CI 14 to 14) (122% increase). Annual increases in the incidence rate of rKR became smaller over the study period. There was a 43.6% reduction in total rKR procedures in 2020 (during the Covid-19 pandemic) compared to 2019. Aseptic loosening was the most frequent indication for rKR overall (20.7% procedures). rKR for aseptic loosening peaked in 2012 and subsequently decreased. rKR for infection increased incrementally over the study period to become the most frequent indication in 2019 (2.7 per 100,000 adults [95% CI 2.6 to 2.9]). Infection accounted for 17.1% first linked rKR, 36.5% second linked rKR and 49.4% third or more linked rKR from 2014 to 2019. Recent trends suggest slowing of the rate of increase in the incidence of rKR. Infection is now the most common indication for rKR, following recent decreases in rKR for aseptic loosening. Infection was prevalent in re-revision KR procedures.
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Abtin Alvand.