Orthopaedic Data Evaluation Panel Research Articles

Total knee arthroplasty: Quality assurance and improved longevity costs less

BackgroundThere is an accepted variation in the financial cost of total knee arthroplasty (TKA) implants but it is not known whether this cost is reflected by the evidence in support of their use. A cost analysis study was carried out to determine the total cost of consumables of a TKA, and whether this was related to the supporting evidence and survivorship data. MethodsIntra-operative data for all unilateral, cemented, primary TKA over a 13 month period at a high-volume Orthopaedic Centre was collected. Level of evidence for each model was taken from the Orthopaedic Data Evaluation Panel (ODEP) website, and data from the UK National Joint Registry was used to assign survivorship (failure rates). Correlation was calculated using the Spearman rank correlation (r). ResultsA total of 1301 TKA were performed at the study centre during the data collection period. The mean cost of consumables for a TKA with patella resurfacing (n = 816) was £1969.08 (range of £1061.46 and £5143.89), and without resurfacing (n = 485) was £1846.62 (range of £1118.98 and £4196.81). There was a negative correlation between price of implant and ODEP rating (r = −0.47), with increasing level of evidence being associated with a lower cost. There was a positive correlation between price of implant and rate of implant failure at the1-, 3- and 5-year time-points (r = 0.55, 0.44, 0.28 respectively), with increasing cost being associated with a higher failure rate. ConclusionHigher financial cost of TKA prostheses was associated with a weaker level of supporting evidence and a higher failure rate. The increased financial cost of new implants may be justified as more data and evidence becomes available to support an advantage in its use over currently established implants.

Does long-term follow-up and monitoring of primary shoulder arthroplasty identify failing implants requiring revision?

Published scoping review has identified evidence paucity related to long-term follow-up of shoulder arthroplasty. We aim to report effectiveness of elective primary shoulder arthroplasty surveillance in identifying failing implants requiring revision. A prospective database recording shoulder arthroplasty and subsequent follow-up surveillance in a shoulder unit was analyzed. Shoulder arthroplasty was performed by 4 fellowship-trained shoulder surgeons for accepted elective indications including the use of anatomic arthroplasty in arthritic shoulders with intact rotator cuff and a reverse prosthesis being used in rotator cuff-deficient shoulders and rotator cuff-competent arthritic shoulders when deemed preferable by the treating surgeon. All shoulder arthroplasty implants used had achieved a minimum 7A Orthopaedic Data Evaluation Panel (ODEP) rating. The included shoulder arthroplasties were performed between May 1, 2004, and December 31, 2021, with minimum 1-year follow-up. Surveillance program involves specialist physiotherapist review at 1, 2, 3, 5, 8, 10, and 15 years postoperatively, including clinical examination, outcome scoring, and radiographs. Patient-initiated review occurred between time points if a patient requested assessment because of symptoms. Outcome measures include ratio of failing implants identified by surveillance and patient-initiated review, with number of surveillance reviews offered and proportion that identified a failing implant requiring revision calculated. A total of 1002 elective primary shoulder arthroplasty with minimum 1-year follow-up were performed (547 reverse total shoulder arthroplasty [rTSA], 234 anatomic total shoulder arthroplasty [aTSA], and 221 hemiarthroplasty [HA]). A total of 238 patients died prior to December 31, 2022, resulting in 4019 surveillance appointments offered. Thirty-eight prostheses required revision ≥1 year postoperatively (6 rTSA, 9 aTSA, and 23 HA), with surveillance identifying requirement in 53% (33% rTSA, 56% aTSA, and 57% HA) and patient-initiated review in 47%. Mean years from implantation to revision was 5.2 (2.7 rTSA, 3.6 aTSA, and 6.6 HA). Revision indications included rotator cuff failure (56% aTSR and 43% HA) and glenoid erosion (57% HA). This is the first series reporting effectiveness of shoulder arthroplasty surveillance in identifying implants requiring revision. Surveillance identified more than half of implants requiring revision, although only 0.5% of appointments identified revision requirement. Surveillance enrolment may influence patient-initiated review utilization; therefore, similar studies using only patient-initiated follow-up would help inform recommendations.

Mid- to late-term follow-up of primary hip and knee arthroplasty: the UK SAFE evidence-based recommendations.

To review the evidence and reach consensus on recommendations for follow-up after total hip and knee arthroplasty. A programme of work was conducted, including: a systematic review of the clinical and cost-effectiveness literature; analysis of routine national datasets to identify pre-, peri-, and postoperative predictors of mid-to-late term revision; prospective data analyses from 560 patients to understand how patients present for revision surgery; qualitative interviews with NHS managers and orthopaedic surgeons; and health economic modelling. Finally, a consensus meeting considered all the work and agreed the final recommendations and research areas. The UK poSt Arthroplasty Follow-up rEcommendations (UK SAFE) recommendations apply to post-primary hip and knee arthroplasty follow-up. The ten-year time point is based on a lack of robust evidence beyond ten years. The term 'complex cases' refers to individual patient and surgical factors that may increase the risk for arthroplasty failure. For Orthopaedic Data Evaluation Panel (ODEP) 10A* minimum implants, it is safe to disinvest in routine follow-up from one to years post-non-complex hip and knee arthroplasty provided there is rapid access to orthopaedic review. For ODEP 10A* minimum implants in complex cases, or non-ODEP 10A* minimum implants, periodic follow-up post-hip and knee arthroplasty may be required from one to ten years. At ten years post-hip and knee arthroplasty, clinical and radiological evaluation is recommended. After ten years post-hip and knee arthroplasty, frequency of further follow-up should be based on the ten-year assessment; ongoing rapid access to orthopaedic review is still required. Complex cases, implants not meeting the ODEP 10A* criteria, and follow-up after revision surgery are not covered by this recommendation.

Implant brand portfolios, the potential for camouflage of data, and the role of the Orthopaedic Data Evaluation Panel in total knee arthroplasty.

Knee arthroplasty surgery is a highly effective treatment for arthritis and disorders of the knee. There are a wide variety of implant brands and types of knee arthroplasty available to surgeons. As a result of a number of highly publicized failures, arthroplasty surgery is highly regulated in the UK and many other countries through national registries, introduced to monitor implant performance, surgeons, and hospitals. With time, the options available within many brand portfolios have grown, with alternative tibial or femoral components, tibial insert materials, or shapes and patella resurfacings. In this study we have investigated the effect of the expansion of implant brand portfolios and where there may be a lack of transparency around a brand name. We also aimed to establish the potential numbers of compatible implant construct combinations. Hypothetical implant brand portfolios were proposed, and the number of compatible implant construct combinations was calculated. A simple knee portfolio with cemented cruciate-retaining (CR) and posterior-stabilized (PS) components, with and without a patella, has four combinations. If there are two options available for each component, the numbers double for each option, resulting in 32 combinations. The effect of adding a third option multiplies the number by 1.3. Introducing compatible uncemented options, with the effect of hybrids, multiplies the number by 4. An implant portfolio with two femoral components (both in CR and PS), with two insert options and a patella, all in cemented and uncemented versions leads to 192 possible compatible implant construct combinations. There are implant brands available to surgeons with many more than two options. This study demonstrates that the addition of multiple variants within a knee brand portfolio leads to a large number (many hundreds) of compatible implant construct combinations. Revision rates of implant combinations are not currently reviewed at this level of granularity, leading to the risk of camouflage of true outcomes. Cite this article: Bone Joint J2021;103-B(10):1555-1560.

Total knee arthroplasty: implant selection and surgical considerations

Choosing a total knee arthroplasty implant can be confusing, with implant manufacturers all providing a wide range of implants even within the same brand. These may vary by design philosophy, fixation, constraint, materials and construct. A surgeon will need to have considered the evidence before making a choice of implant, and this evidence can be in the form of large cohorts of registry-based data, that may lack detail, or small studies that may be too small to be valid or have wider application. This article reviews the sources of data available to surgeons and discusses the categories of implant available to the surgeon. Variations in patient anatomy and pathology may require a surgeon to be familiar with a range of implant options. Surgeons should be aware of how their chosen implant performs, not just in studies from the designer, but in independent series and on national registries, and should know the UK Orthopaedic Data Evaluation Panel (ODEP) rating of the specific detailed construct that they are regularly using.

Mortality and revision rate of cemented and uncemented hemiarthroplasty after hip fracture: an analysis of the Dutch Arthroplasty Register (LROI)

Background and purpose — Femoral neck fractures are commonly treated with cemented or uncemented hemiarthroplasties (HA). We evaluated differences in mortality and revision rates in this fragile patient group.Patients and methods — From January 1, 2007 until December 31, 2016, 22,356 HA procedures from the Dutch Arthroplasty Register (LROI) were included. For each HA, follow-up until death, revision, or end of follow-up (December 31, 2016) was determined. The crude revision rate was determined by competing risk analysis. Multivariable Cox regression analyses were performed to evaluate the effect of fixation method (cemented vs. uncemented) on death or revision. Age, sex, BMI, Orthopaedic Data Evaluation Panel (ODEP) rating, ASA grade, surgical approach, and previous surgery were included as potential confounders.Results — 1-year mortality rates did not differ between cemented and uncemented HA. 9-year mortality rates were 53% (95% CI 52–54) in cemented HA compared to 56% (CI 54–58) in uncemented HA. Multivariable Cox regression analysis showed similar mortality between cemented and uncemented HA (HR 1.0, CI 0.96–1.1). A statistically significantly lower 9-year revision rate of 3.1% (CI 2.7–3.6) in cemented HA compared with 5.1% (CI 4.2–6.2) in the uncemented HA was found with a lower hazard ratio for revision in cemented compared with uncemented HA (HR 0.56, CI 0.47–0.67).Interpretation — Long-term mortality rates did not differ between patients with a cemented or uncemented HA after an acute femoral neck fracture. Revision rates were lower in cemented compared with uncemented HA.

Custom made total knee arthroplasty : Review of current literature

Custom-designed total knee replacement has become astandard procedure in some orthopaedic centres worldwide. Due to the lack of literature, the discussion about the hypothetical advantages has remained controversial. It was the aim of this study to focus on the current literature on custom-made total knee arthroplasty. We can demonstrate that custom-made total knee arthroplasty is areproducible strategy with good clinical results in terms of leg-axis reconstruction, natural kinematics, patient-related outcomes and cost effectiveness. This has led to the fact that the Orthopaedic Data Evaluation Panel (ODEP) of the National Health Service in Great Britain rated the Conformis custom-designed knee replacement in 2017 with a3D rating.

Safety and Effectiveness of Shoulder Arthroplasties in Spain: A Systematic Review

The effectiveness and safety of shoulder arthroplasties in the general context of a Spanish patient population remains unclear. The aim of this study was to ascertain both the effectiveness and safety of primary shoulder arthroplasties and the prosthesis types used in Spain. A systematic review of all the available literature evaluating the effectiveness and safety of primary shoulder arthroplasties in Spain was performed. A narrative synthesis was performed, and evidence tables were created in four dimensions: study design, arthroplasty characteristics, safety, and effectiveness. Orthopaedic Data Evaluation Panel (ODEP) scores were used to evaluate prosthesis types. Twenty-one studies were selected that included a total of 1293 arthroplasties. The most common indication was fractures, while the prosthesis most frequently used was the Delta Xtend (ODEP 10A). The most common complication was scapular notching. Prosthesis revision rate was approximately 6% for follow-ups between 12 and 79 months. In addition, significant improvements were observed in the Constant–Murley test score after the intervention. Currently in Spain, shoulder arthroplasty can be considered a safe and effective procedure with functional recovery and pain reduction for eligible patients with humeral fracture, rotator cuff arthropathy, fracture sequelae and malunion of the proximal humerus, and degenerative disease. Future longitudinal research and population-based studies could serve to confirm these results and identify points of improvement.

Guidelines for the follow-up of total hip arthroplasty: do they need to be revised?.

The aim of this retrospective audit was to determine the route of referral or presentation of patients requiring revision following primary total hip arthroplasty (THA). A total of 4802 patients were implanted with an Orthopaedic Data Evaluation Panel (ODEP) 10A* cementless implant (Corail/Pinnacle) between 2005 and 2015; 80 patients with a mean age of 67.8 years (sd 10.8) underwent a subsequent revision. The primary outcome measure was route of referral for revision. Of the 80 revisions, 31 (38.8%) took place within the first year and 69 (86.3%) took place within six years. Only two of the 80 patients were picked up at a routine review clinic, one for infection and the other for liner dissociation. A total of 36 revised patients (45.0%) were reviewed following self-referral. Of the remaining 44 revised patients (55.0%), 15 (18.8%) were General Practitioner referrals, 13 (16.3%) were other hospital referrals, six (7.5%) were inpatients, six (7.5%) were Emergency Department referrals, and two (2.5%) were readmitted from their homes. No revisions were carried out on asymptomatic patients. Our experience suggests that if there is a robust system in place for self-referral, patients with an ODEP 10A* hip implant can, if asymptomatic, be safely discharged at the time of their first postoperative review. Cite this article: Bone Joint J 2019;101-B:536-539.

Hip hemiarthroplasty for fractured neck of femur; a freedom of information study to assess national variation in implant selection and procurement

IntroductionDuring 2016, according to the National Hip Fracture Database (NHFD), over 65,000 patients suffered a hip fracture of which approximately half underwent hemiarthroplasty. Clear guidelines exist on the usage of proven cemented implants. The Getting It Right First Time (GIRFT) Report highlighted the financial implications of ‘unwarranted variation’ and stressed the importance of rationalising and standardising service provision, in particular implant usage. The primary aims of this study were to investigate the variation in hip hemiarthroplasty implant usage and associated costs. We hypothesised there to be large variation in implants used and procurement costs. MethodsFreedom of Information Requests (FOI) were sent to all 177 hospitals listed in the 2017 NHFD Report as treating hip fracture patients. All hospitals were asked for their most commonly used hemiarthroplasty implant and the cost of this, per patient. ResultsOne hundred sixty six (94%) responses were received. Eighty four (51%) provided implant name and cost, 78 (47%) provided implant name but refused costs and 4 (3%) refused to provide any details. Nineteen different prostheses were used nationally with 20 hospitals using a non-ODEP (Orthopaedic Data Evaluation Panel) 10A implant. Average total cost was £725.00 (range £71-£1378). Significant cost variation was demonstrated for the same implants; one implant was £978.19 at it’s most costly and £285.59 at it’s cheapest. DiscussionThe aims of this study have been met. We have demonstrated huge variation in the implants used for hip hemiarthroplasty and their costs. Notwithstanding the nuances of departmental procurement processes, the financial implications for this variation are significant. ConclusionsThis article demonstrates a requirement for rationalisation of implant usage and procurement in order to potentially improve patient outcomes and provide opportunities for significant cost saving in an already overstretched health service.

Mid-term clinical results of the cementless R3 cup and Polarstem total hip arthroplasty.

There has been a shift from cemented to uncemented hip arthroplasty. One popular uncemented combination is the R3 acetabular cup with Polarstem, having the lowest revision rate in the UK National Joint Registry. However, there are no medium-term clinical outcomes on this combination in the literature. The aim of this study is to review our centre's outcomes with this combination using conventional bearings with a minimum of 7-year follow-up. Using our centre's arthroplasty database, we identified all patients that underwent a total hip arthroplasty using these implants from August 2009 to December 2010. One hundred and forty-four procedures were performed. The primary outcome was revision rate, and the secondary outcomes were clinical and radiological evaluation. The mean cohort age at surgery was 68.3years. There were three revisions, of which only one underwent a cup revision. The mean Oxford Hip Score at 7-year follow-up was 38. Radiological evaluation of both acetabular and stem component did not show any radiolucency at 7-year follow-up. Kaplan-Meier survivorship analysis showed an implant survival rate of 97.69% at 7years using revision for all causes as endpoint. The risk of revision was 1.47% at 7years. Our revision rates are comparable to the UK's National Joint Registry, with excellent clinical and radiological outcome. Our results correlate with the allocated rating of 7A* by the Orthopaedic Data Evaluation Panel for both R3 acetabular cup and Polarstem.

R3 Cup Does Not Have a High Failure Rate in Conventional Bearings: A Minimum of 5-Year Follow-Up

BackgroundThe R3 cementless acetabular system was first marketed in Australia and Europe in 2007. Previous papers have shown high failure rates of the R3 cup with up to 24% with metal-on-metal bearing. There are currently no medium term clinical results on this cup. The aim of the study is to review our results of the R3 acetabular cup with conventional bearings with a minimum of 5-year follow-up. MethodsPatients who were implanted with the R3 acetabular cup were identified from our center's arthroplasty database. A total of 293 consecutive total hip arthroplasties were performed in 286 patients. The primary outcome was revision. The secondary outcomes were the Oxford Hip Scores (OHS) and radiographic evaluation. ResultsThe mean age of the patients was 69.4 years. The mean preoperative OHS was 23 (range 10-34) and the mean OHS was 40 (range 33-48) at the final follow-up. Radiological evaluation showed an excellent ARA score in all patients at 5 years. None of the R3 cups showed osteolysis at the final follow-up. There were 3 revisions in our series, of which 2 R3 cups were revised. The risk of revision was 1.11% at 5 years. ConclusionOur experience of using the R3 acetabular system with conventional bearings showed high survivorship and is consistent with the allocated Orthopaedic Data Evaluation Panel rating of 5A* as rated in 2015 in the United Kingdom.

Primary total hip arthroplasty in Catalonia: What is the clinical evidence that supports our prosthesis?

IntroductionThe implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). Material and methodsA review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. ResultsA total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. ConclusionsThere was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period.

Artroplastias primarias de cadera implantadas en Cataluña: ¿qué evidencia clínica respalda a nuestras prótesis?

IntroductionThe implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). Material and methodsA review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. ResultsA total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. ConclusionsThere was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period.

Measuring knee arthroplasty outcomes

Outcome measures are increasingly used by clinicians, healthcare providers and implant manufacturers for a variety of reasons. Clinical outcome studies have traditionally been used but the level of evidence presented has been variable. In recent decades joint registries have provided useful data on implant survival, but implant revision as an outcome measure has restrictions as many factors contribute to it. Patient reported outcome scores have been introduced more recently and provide important information about health gain after surgical intervention. In response to guidelines from the National Institute for Clinical Excellence, the Orthopaedic Data Evaluation Panel assesses and rates implants, and Beyond Compliance advises implant manufacturers of the level of risk of newly introduced or modified prostheses.

Finding the right hip implant for patient and surgeon: the Dutch strategy--empowering patients.

We describe the implementation process of hip prostheses selection in the Netherlands. The recent problems with large head metal-on-metal hip prostheses resulted in substantial damage to the surgeons' credibility and reputation in the media. This led to a true sense of urgency among orthopaedic surgeons to increase their activities to secure patient safety. The board of the Dutch Orthopaedic Association (NOV) in the Netherlands established a Dutch Hip Task Force (DHTF) with the explicit assignment of formulating criteria to classify the quality of total hip implants on the Dutch market based on survivorship. The aim was to offer unequivocal information enabling a balanced choice of total hip prosthesis. The ultimate goal of the NOV is that all implanted total hip prostheses implanted in the Netherlands are based on reliable clinical evidence. The DHTF decided to adapt the principles of the National Institute for Health and Care Excellence (NICE, UK) (www.nice.org.uk). The taskforce uses data from the registries as well as the Orthopaedic Data Evaluation Panel (ODEP). If the ODEP guidelines had been chosen as standard alone, one quarter of our listed hip components would not have been included. In our view this underlines the strength in the Dutch approach where high quality registry data and ODEP ratings are complementary and result in a list of reliable hip prostheses. Most importantly we offer patients insights into the known quality of the implants by sharing the results of our implant review. This will facilitate shared decision making by empowering patients in their knowledge on available hip arthroplasties.

Primary hip replacement prostheses and their evidence base: systematic review of literature

Objective To determine the extent to which prostheses with no readily available evidence to support their use are being implanted in primary total hip arthroplasty.Design Systematic review of the literature.Data...

(i) Introduction and follow-up of new implants

The recent recall of Articular Surface Resurfacing implants (ASR, DePuy Orthopaedics, Warsaw, Indiana) has yet again triggered a debate on the regulation of introduction and follow-up of new/modified orthopaedic implants in the market. Although the National Joint Registry was helpful in identifying the failing ASR implant, it took almost seven years from the introduction of the implant to the market to finally recalling it from the market. A comprehensive review of the systems needs to be done to prevent poorly designed implants from making it to the market and also to minimize the delay in identifying any potentially failing implants in use. The pre-market approval process (the CE [Conformite Europeenne] marking in the United Kingdom [UK] and Europe) needs to be more stringent and be able to strike a balance between ensuring patient safety and promoting innovation. The post-market surveillance needs to be more effective to identify the failing implants early, and with the largest joint registry in the world, the UK is in an ideal position to provide this kind of surveillance. Better linkage with well-established regulatory authorities (The Orthopaedic Data Evaluation Panel and the Medicines and Healthcare products Regulatory Agency) and the use of Patient Reported Outcome Measures can make this process more effective.

Monitoring the Introduction and Performance of a Joint Replacement: The United Kingdom Metal-on-Metal Alert

Recent events have made us question our ability to monitor the introduction and performance of a new prosthetic joint replacement. These concerns are mirrored in many other countries, even those with joint registries and other systems for detecting poorly performing implants. In the United Kingdom, as is the case in most European Union countries, we have assessment processes in place, particularly the CE (Conformité Européenne) mark, the National Joint Registry, and the Orthopaedic Data Evaluation Panel. It is important to realize that these organizations can only react to poor performance; it is not within their power as monitoring agencies to prevent a poor implant from entering the market. When an implant has been shown to perform badly, it is referred to the Medicines and Healthcare products Regulatory Agency (MHRA), which then discusses the report with the manufacturer. When it is deemed that there is unequivocal evidence of a serious problem with the implant, the MHRA issues alerts to all hospitals and practitioners. We have continuing concerns about how to assess and monitor modifications to already existing devices. Suggestions are made for improvements to this system, and the authors will welcome feedback.

Critical Commentary toA Case Report of Early Idiopathic Portal Hypertension

Outcome measures are increasingly used by clinicians, healthcare providers and implant manufacturers for a variety of reasons. Clinical outcome studies have traditionally been used but the level of evidence presented has been variable. In recent decades joint registries have provided useful data on implant survival, but implant revision as an outcome measure has restrictions as many factors contribute to it. Patient reported outcome scores have been introduced more recently and provide important information about health gain after surgical intervention. In response to guidelines from the National Institute for Clinical Excellence, the Orthopaedic Data Evaluation Panel assesses and rates implants, and Beyond Compliance advises implant manufacturers of the level of risk of newly introduced or modified prostheses.