Aims. The aim of this study was to determine whether patients with metal-on-metal (MoM) arthroplasties of the hip have an increased risk of cardiac failure compared with those with alternative types of arthroplasties (non-MoM). Patients and Methods. A linkage study between the National Joint Registry, Hospital Episodes Statistics and records of the Office for National Statistics on deaths was undertaken. Patients who underwent elective total hip arthroplasty between January 2003 and December 2014 with no past history of cardiac failure were included and stratified as having either a MoM (n = 53 529) or a non-MoM (n = 482 247) arthroplasty. The primary outcome measure was the time to an admission to hospital for cardiac failure or death. Analysis was carried out using data from all patients and from those matched by propensity score. Results. The risk of cardiac failure was lower in the MoM cohort compared with the non-MoM cohort (adjusted hazard ratio (aHR) 0.901; 95% confidence interval (CI) 0.853 to 0.953). The risk of cardiac failure was similar following matching (aHR 0.909; 95% CI 0.838 to 0.987) and the findings were consistent in subgroup analysis. Conclusion. The risk of cardiac failure following total hip arthroplasty was not increased in those in whom MoM implants were used, compared with those in whom other types of prostheses were used, in the first seven years after surgery. Cite this article: Bone Joint J 2018;100-B:20–7

Aims. Many case reports and small studies have suggested that cobalt ions are a potential cause of cardiac complications, specifically cardiomyopathy, after metal-on-metal (MoM) total hip arthroplasty (THA). The impact of metal ions on the incidence of cardiac disease after MoM THA has not been evaluated in large studies. The aim of this study was to compare the rate of onset of new cardiac symptoms in patients who have undergone MoM THA with those who have undergone metal-on-polyethylene (MoP) THA. Patients and Methods. Data were extracted from the Standard Analytics Files database for patients who underwent MoM THA between 2005 and 2012. Bearing surface was selected using International Classification of Diseases ninth revision codes. Patients with a minimum five-year follow-up were selected. An age and gender-matched cohort of patients who underwent MoP THA served as a comparison group. New diagnoses of cardiac disease were collected during the follow-up period. Comorbidities and demographics were identified and routine descriptive statistics were used. Results. We identified 29 483 patients who underwent MoM THA and 24 175 matched patients who underwent MoP THA. Both groups had a mean Charlson comorbidity index score of 4. There were no statistically significant differences in 30 of 31 pre-existing comorbidities. Patients undergoing MoM THA had a slightly lower incidence of cardiac failure compared with those undergoing MoP THA at three years (6.60% versus 7.06%, odds ratio (OR) 0.93, 95% confidence interval (CI) 0.87 to 0.99) and four years (8.73% versus 9.49%, OR 0.91, 95% CI 0.86 to 0.97) postoperatively, with no difference in the incidence of new cardiac failure in between the groups at five years. There was no statistically significant difference in the incidence of arrhythmia, myocardial infarction and cardiomyopathy at any time between the two groups. Conclusion. MoM THA is not associated with cardiac complications. Initial reports may have represented individual instances of cardiac disease in patients with a failing MoM articulation rather than an emerging epidemiological trend. Cite this article: Bone Joint J 2018;100-B:28–32

Elevated blood cobalt secondary to metal-on-metal (MoM) hip arthroplasties has been shown to be a risk factor for developing cardiovascular complications including cardiomyopathy. Published case reports document cardiomyopathy in patients with blood cobalt levels as low as 13µg/l (13ppb, 221nmol/l). Clinical studies have found conflicting evidence of cobalt-induced cardiomyopathy in patients with MoM hips. Global longitudinal strain (GLS) is an echocardiography measurement known to be more sensitive than ejection fraction at diagnosing early cardiomyopathies. The extent of cardiovascular injury, as measured by GLS, in patients with elevated blood cobalt levels has not previously been examined. Sixteen patients with documented blood cobalt ion levels above 13µg/l were identified from a regional arthroplasty database. They were matched with eight patients awaiting hip arthroplasty with no history of cobalt implants. All patients underwent electrocardiogram and echocardiogram assessment for signs of cardiomyopathy including GLS. Patients with MoM hip arthroplasties had a mean blood cobalt level of 29µg/l (495nmol/l) compared to 0.01µg/l (0.2nmol/l) in the control group. There was no difference or correlation in ejection fraction (EF), left ventricular (LV) end systolic dimension, LV end diastolic dimension, fractional shortening, ventricular wall thickness or E/e’ ratio. However, GLS was significantly reduced in patients with MoM hip arthroplasties compared to those without (−15.2% v −18%, (MoM v control) p= 0.0125). Pearson correlation demonstrated that GLS is significantly correlated with blood cobalt level (r= 0.8742, p=0.0009). For the first time, this study has demonstrated reduced cardiac function in the presence of normal EF as assessed by GLS in patients with elevated cobalt above 13µg/l. As GLS is a more sensitive measure of systolic function than EF, routine echocardiogram assessment including GLS should be performed in all patients with MoM hip arthroplasties and elevated blood cobalt above 13µg/l. Further work is recommended to assess if these cardiac changes are present in patients with elevated blood cobalt levels below 13µg/l

In a prospective, controlled study, we measured the effect on cardiac output of the introduction of methylmethacrylate during hemiarthroplasty for displaced fractures of the femoral neck. We treated 20 elderly patients who were similar in age, height, weight and preoperative left ventricular function with either cemented or uncemented hemiarthroplasty. Using a transoesophageal Doppler probe, we measured cardiac output before incision and at six stages of the procedure: during the surgical approach, reaming and lavage of the femoral canal, the introduction of cement, the insertion of the prosthesis, and in reduction and closure. We found that before the cement was introduced, there was no difference in stroke volume or cardiac output (p > 0.25). Cementation produced a transient but significant reduction in cardiac output of 33% (p < 0.01) and a reduction in stroke volume of 44% (p < 0.02). The introduction of cement did not affect the heart rate or mean arterial pressure. There was no significant difference in cardiac function on insertion of the prosthesis. Standard non-invasive haemodynamic monitoring did not detect the cardiovascular changes which may account for the sudden deaths that sometimes occur during cemented hemiarthroplasty. The fall in stroke volume and cardiac output may be caused by embolism occurring during cementation, but there was no similar fall during reaming or insertion of the prosthesis

Circulating cobalt and chromium from metal-on-metal implants cause rare but fatal autopsy-diagnosed cardiotoxicity. Concern exists that milder cardiotoxicity may be common and under-recognized. Unacceptably high failure rates of metal-on-metal hip implants have prompted regulatory authorities to issue worldwide safety alerts. Despite this, approximately 1 million patients continue to live with metal-on-metal implants, putting them at risk of systemic toxicity. Although blood cobalt and chromium levels are easily measured and track local toxicity, no non-invasive tests for organ deposition exist. We recently demonstrated the utilisation of a T2* protocol (cardiovascular MRI) to detect cobalt and chromium deposition within the liver of a patient with elevated blood cobalt levels (confirmed by liver biopsy tissue analysis and X-ray fluorescence spectroscopy). We sought to detect and constrain the correlation between blood metal ions and a comprehensive panel of established markers of early cardiotoxicity. In addition we applied T2* protocols with the aim of detecting cardiac metal deposition. 90 patients were recruited through RNOH clinics into this prospective single centre blinded study. Patients were divided into 3 age and gender-matched groups according to type of implant and blood metal ion levels as follows: [Group A] Non-metal bearing hip implants; [Group B] Metal-on-metal implants, low blood metal ion levels (<7ppb); and [Group C] Metal-on-metal implants, high blood levels (>7ppb). All underwent detailed cardiovascular phenotyping using cardiac MRI (with T2*, T1 and ECV mapping, in addition to LV size and ejection fraction), advanced echocardiography (LV size and ejection fraction), and cardiac blood biomarker (Troponin and BNP) sampling in the same sitting at the Heart Hospital London. Primary outcomes were pre-specified. See study flow diagram – figure 1. (The study was registered with . clinicaltrials.gov. : NCT02331264). Blood cobalt levels were significantly different between groups (0.17ppb (range 0·10–0·47, SD 0·08) vs. 2·47 (0·72–6·9, SD 1·81) vs. 30·0 (7·54–118.0, SD 29·1) respectively for groups A, B and C). No significant between-group differences were found for LV size, ejection fraction (CMR or echocardiography), LA size, T1, T2*, ECV, BNP or troponin, with all results within normal ranges. There was no relationship between blood cobalt levels and either left ventricular ejection fraction or T2* (r=-0·022 and r=-0·108 respectively). Although small, the study was sufficiently powered to detect, as a minimum, a difference in ejection fraction of 4.8% (Cohen's d effect size 0·8). Using best available technologies, exposure of patients with metal-on-metal hip implants to high (but not extreme) blood cobalt and chromium levels has no detectable effect on the heart. We believe these findings will offer reassurance to one million patients worldwide living with a metal-on-metal hip implant and will support clinicians caring for such patients. For any figures or tables, please contact the authors directly by clicking on ‘Info & Metrics’ above to access author contact details

Elevated blood cobalt secondary to metal-on-metal (MoM) hip arthroplasties has been shown to be a risk factor for developing cardiovascular complications including cardiomyopathy. Published case reports document cardiomyopathy in patients with blood cobalt levels as low as 13µg/l. Clinical studies have found conflicting evidence of cobalt-induced cardiomyopathy in patients with MoM hips. The extent of cardiovascular injury, measured by global longitudinal strain (GLS), in patients with elevated blood cobalt levels has not previously been examined. Sixteen patients with prospectively collected blood cobalt ion levels above 13µg/l were identified and matched with eight patients awaiting hip arthroplasty with no history of cobalt implants. Patients underwent echocardiogram assessment including GLS. Patients with MoM hip arthroplasties had a mean blood cobalt level of 29µg/l compared to 0.01µg/l in the control group. There was no difference or correlation in EF, left ventricular (LV) end systolic dimension, LV end diastolic dimension, fractional shortening, ventricular wall thickness or E/e’ ratio. However, GLS was significantly reduced in patients with MoM hip arthroplasties compared to those without (−15.2% v −18%, (MoM v control) p= 0.0125). Pearson correlation demonstrated that GLS is significantly correlated with blood cobalt level (r= 0.8742, p=0.0009). For the first time, this study has demonstrated reduced cardiac function in the presence of normal EF as assessed by GLS in patients with elevated cobalt above 13µg/l. As GLS is a more sensitive measure of systolic function than EF, routine echocardiogram assessment including GLS should be performed in all patients with MoM hip arthroplasties and elevated blood cobalt

The Canadian Cardiovascular Society (CCS) recommends performing daily troponin testing on postoperative days 0 through 3 for noncardiac surgical patients to decrease the mortality rate due to myocardial injury. Indications for testing include:. ->65 yo. -45-64 yo with significant cardiovascular disease. -a Revised Cardiac Risk Index score (RCRI) > 1. Troponin elevation > 30 ng/L is termed “myocardial injury after noncardiac surgery” (MINS). The study objective was to determine the prognostic relevance of applying CCS recommendations. 669 patients undergoing THA were included in the study. Based on the CCS recommendation there were 4 patient Groups depending on whether or not they met the MINS screening protocol criteria and whether or not it was applied:. -A - met & applied (n=181). -B - met & not applied (n=248). -C – not met & applied (n=10). -D – not met & not applied (n=230). 307 (45.8%) males and 363 (54.2%) females with an average age of 67.8 years were included. Group A- 24% incidence (43 patients) of troponin rise & 5% incidence (9 patients) of cardiac complications. Group B- 0.4% incidence (1 patient) of cardiac complications. Groups A + B – representing all patients who should have had the MINS screening protocol applied according to the CCS recommendations − 10 (2.3%) patients developed cardiac complication and one (0.2%) patient death. MINS screening protocol group (A & C) LOS was 4.0 days compared to 1.4 days for those not screened (p-value: <0.001). Applying the CCS MINS screening protocol to elective THA patients added no benefit in predicting/preventing postoperative cardiac events but was associated with a significant increase in LOS. Following current CCS recommendations without more specifications and clinical evidence is unwarranted

Aims. Cardiac magnetic resonance (CMR) was used to assess whether cardiac function or tissue composition was affected in patients with well-functioning metal-on-metal hip resurfacing arthroplasties (MoMHRA) when compared with a group of controls, and to assess if metal ion levels correlated with any of the functional or structural parameters studied. Patients and Methods. In all, 30 participants with no significant cardiac history were enrolled: 20 patients with well-functioning MoMHRA at mean follow-up of 8.3 years post-procedure (ten unilateral, ten bilateral; 17 men, three women) and a case-matched control group of ten non-MoM total hip arthroplasty patients (six men, four women). The mean age of the whole cohort (study group and controls) at the time of surgery was 50.6 years (41.0 to 64.0). Serum levels of cobalt and chromium were measured, and all patients underwent CMR imaging, including cine, T2* measurements, T1 and T2 mapping, late gadolinium enhancement, and strain measurements. Results. None of the MoMHRA patients showed clinically significant cardiac functional abnormality. The MoMHRA patients had larger indexed right and left end diastolic volumes (left ventricular (LV): 74 ml/m. 2. vs 67 ml/m. 2. , p = 0.045; right ventricular: 80 ml/m. 2. vs 71 ml/m. 2. , p = 0.02). There was a small decrease in T2 time in the MoMHRA patients (median 49 ms vs 54 ms; p = 0.0003). Higher metal ion levels were associated with larger LV volumes and with shorter T2 time. Conclusion. Although cardiac function is not clinically adversely affected in patients with well-functioning MoMHRA, modern imaging is able to demonstrate subtle changes in structure and function of the heart. As these changes correlate with systemic ion measurements, they may be consequences of wear debris deposition. Longer, longitudinal studies are necessary to determine whether cardiac function will become affected. . Cite this article: Bone Joint J 2019;101-B:540–546

Whilst total hip replacement (THR) is generally safe and effective, pre-existing medical conditions, particularly those requiring inpatient admission, may increase the risk of post-operative mortality. Delaying elective surgery may reduce the risk, but it is unclear how long a delay is sufficient. We analysed 958,145 primary THRs performed for solely osteoarthritis April 2003-December 2018, in the NJR linked to Hospital Episodes Statistics to identify inpatient admissions prior to elective THR for 17 conditions making up the Charlson index including myocardial infarction, congestive heart failure, cerebrovascular disease and diabetes. Crude analyses used Kaplan-Meier and adjusted analyses used Cox modelling. Patients were categorised for each co-morbidity into one of four groups: not recorded in previous five-years, recorded between five-years and six-months before THR, recorded six-months to three-months before THR, and recorded between three-months and day before surgery. 90-day mortality was 0.34% (95%CI: 0.33–0.35). In the 432 patients who had an acute MI in the three months before THR, this figure increased to 18.1% (95%CI 14.8, 22.0). Cox models observed 63 times increased hazard of death within 90-days if patients had an acute MI in the 3-months before their THR, compared to patients who had not had an MI in the five years before their THR (HR 63.6 (95%CI 50.8, 79.7)) This association reduced as the time between acute MI and THR increased. For congestive cardiac failure, the hazard in the same scenario was 18-times higher with a similar protective effect of delaying surgery. Linked NJR and HES data demonstrate an association between inpatient admission for acute medical co-morbidities and death within 90-days of THR. This association is greatest in MI, congestive cardiac failure and cerebrovascular disease with smaller associations observed in several other conditions including diabetes. The hazard reduces when longer delays are seen between the admission for acute medical conditions and THR in all diagnoses. This information will help patients with previous medical admissions and surgeons to determine optimal timing for surgery

Aims. Two-stage exchange revision total hip arthroplasty (THA) performed in case of periprosthetic joint infection (PJI) has been considered for many years as being the gold standard for the treatment of chronic infection. However, over the past decade, there have been concerns about its safety and its effectiveness. The purposes of our study were to investigate our practice, collecting the overall spacer complications, and then to analyze their risk factors. Methods. We retrospectively included 125 patients with chronic hip PJI who underwent a staged THA revision performed between January 2013 and December 2019. All spacer complications were systematically collected, and risk factors were analyzed. Statistical evaluations were performed using the Student's t-test, Mann-Whitney U test, and Fisher's exact test. Results. Our staged exchange practice shows poor results, which means a 42% mechanical spacer failure rate, and a 20% recurrent infection rate over the two years average follow-up period. Moreover, we found a high rate of spacer dislocation (23%) and a low rate of spacer fracture (8%) compared to the previous literature. Our findings stress that the majority of spacer complications and failures is reflecting a population with high comorbid burden, highlighted by the American Society of Anesthesiology grade, Charlson Comorbidity Index, and Lee score associations, as well as the cardiac, pulmonary, kidney, or hepatic chronic conditions. Conclusion. Our experience of a two-stage hip exchange revision noted important complication rates associated with high failure rates of polymethylmethacrylate spacers. These findings must be interpreted in the light of the patient’s comorbidity profiles, as the elective population for staged exchange has an increasing comorbid burden leading to poor results. In order to provide better results for this specific population, our conclusion suggests that comparative strategy studies are required to improve our therapeutic indication. Cite this article: Bone Jt Open 2022;3(6):485–494

Two-stage exchange revision total hip arthroplasty performed in case of infection has been considered during many years the gold standard for treatment of chronic infection. Nevertheless, during the last decade, concerns have risen regarding its safety and its efficiency. The purpose of our study was to, first investigate the spacer complications, then to analyze their risks factors. We retrospectively included 125 patients with chronic hip periprosthetic joint infection who underwent a two stage exchange revision arthroplasty performed between January 2013 and December 2019. All spacer complications were systematically collected and risk factors were analyzed. Statistical evaluation were performed using the Student and Mann-Whitney tests. Our study confirms the hypothesis of a high-risk strategy with 42% of patients who had a mechanical spacer failure and a 20% recurrence of infection during the average two years period of follow-up. We found a high rate of spacer migration (23%) and a low rate of spacer fracture (8%) compared to literature. The most important finding was that the majority of spacer complications and failures were found in a population with high medical comorbidities as highlighted by the ASA, Charlson and Lee score associations, as well as with the cardiac, pulmonary, kidney or hepatic chronic conditions. This study showed that a two-stage hip exchange revision is a high-risk procedure regarding complications and mechanical failures of PMMA spacers. In patients with high medical comorbidities, other strategies may be considered and interdisciplinary cooperation with other facilities are needed to identify and control each risk factor

Introduction. Total hip arthroplasty (THA) is gaining popularity as a treatment for displaced femoral neck fractures (FNF), especially in physiologically younger patients. While elective THA for primary osteoarthritis (OA) has demonstrated low rates of complications and readmissions, the outcomes of THA for FNF are less predictable. Additionally, these THA procedures are equally included in various alternative payment bundles. Therefore, the aim of this study is to assess postoperative complication rates after THA for primary OA compared with FNF. Methods. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2008 to 2016 was queried. Patients were identified using the Current Procedural Terminology (CPT) code for THA (27130) and divided into groups by diagnosis; OA in one group and FNF in another. Univariate statistics were performed. T-test compared continuous variables between groups, and Chi-square test compared categorical variables. Multivariate and propensity matched logistic regression analyses were performed to control for risk factors of interest. The primary outcomes for this study were death or serious morbidity (surgical site infection (SSI), infection, respiratory complication, cardiac complication, sepsis, or blood loss anemia requiring postoperative transfusion). Additional secondary outcomes included the incidence of specific complications, total operative time (time from incision to closure), length of hospital stay and proportion of patients that were discharged home. Results. Analyses included 139,635 patients undergoing THA. OA was the indication in 135,013 cases and FNF in 4,622 cases. Unadjusted analysis showed a significantly higher rate of mortality when THA was done for hip fracture (2.1% vs. 0.1%; p<0.001). There was also a significantly increased rate of serious morbidity for hip fracture patients; including cardiac complications (3.5% vs 0.96%; p<0.001), respiratory complications (1.3% vs 0.2%; p<0.001), postop transfusion (23.1% vs 9.36%; p<0.001), sepsis (0.95% vs 0.3%; p<0.001). There was a significantly higher percentage of patients requiring reoperation (4.5% vs 2.0%; p<0.001) and readmission (8.0% vs 3.5%; p<0.001) in the hip fracture group. There was a significantly higher percentage of patients in the hip fracture groups having operative time >90min (16.4% vs 10.1%; p<0.001), length of stay longer than 5 days (53.8% vs 7.5%; p<0.001), and a significantly lower percentage of patients who were discharged home (39.0% vs 78.0%; p<0.001). Propensity score matching resulted in a cohort of 6,968 patients; 3,484 in both the hip fracture and osteoarthritis groups. Mortality within 30 days was 530% higher, and major morbidity was 36% higher among FNF patients. Reoperation was 40% higher, readmission was 36% higher, operative length at the 90th percentile was 74% higher, prolonged length of stay was 838% higher, and discharge to home was 62% lower for the FNF group compared with OA patients. Logistic, reverse stepwise regression model () results were consistent with the propensity-matched analysis. Discussion and Conclusion. This large database study showed a higher risk of postoperative complications including mortality, major morbidity, reoperation, readmission, prolonged operative time, increased length of stay, and decreased likelihood of discharge home in patients undergoing THA for FNF compared with OA. Without risk adjustment, the bundled payment methods that are applied to THA procedures including those performed for FNF are at a disadvantage and likely inadequate to cover the more costly episode of care related to treating hip fracture patients

Background. 91% of blood loss in Total Hip Replacement (THR) occurs in the period after skin closure and the first 24 post-operative hours. TRAC-24 was established to identify if an additional 24-hour post-operative oral regime of Tranexamic acid (TXA) is superior to a once-only intravenous dose at surgery. Methods. This was a prospective, phase IV, single centered, open label, parallel group controlled trial on patients undergoing primary elective THR. A history of thromboembolic or cardiovascular disease were not exclusion criteria. The primary outcome was indirect calculated blood loss at 48 hours (IBL). 534 patients were randomized on a 2:2:1 ratio over three different groups. Group 1 received an intravenous dose of TXA at the time of surgery and an additional 24-hour post-operative oral regime, Group 2 only received the intra-operative dose and Group 3 did not receive any TXA. Results. 233, 235 and 66 patients were recruited to groups 1,2 and 3. All groups had comparable baseline characteristics. 3.2% of all patients had previous thromboembolism and 5.4% had previous cardiac stenting. Group 3 mean (SD) IBL was 1371 (630) ml whereas group 1 and 2 combined had a mean (SD) IBL of 846 (471), p<0.001. There was no overall difference in IBL between group 1 and group 2, but subgroup analysis observed 12% less blood loss in group 1 than group 2 in the 36 patients weighing >100kg. No differences in mortality or thromboembolic events were observed in any group. Conclusion. The use of a single, intravenous, peroperative, 1-gram dose of Tranexamic acid decreased the total blood loss associated with THA by 38%. The addition of another 24-hours oral tranexamic acid did not provide additional benefit but further study on the effect of patient weight is required. Tranexamic acid is safe in patients with history of thromboembolic and cardiovascular disease

Aims

To develop prediction models using machine-learning (ML) algorithms for 90-day and one-year mortality prediction in femoral neck fracture (FNF) patients aged 50 years or older based on the Hip fracture Evaluation with Alternatives of Total Hip arthroplasty versus Hemiarthroplasty (HEALTH) and Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trials.

Aims

Hip fractures are some of the most common fractures encountered in orthopaedic practice. We aimed to identify whether perioperative hypotension is a predictor of 30-day mortality, and to stratify patient groups that would benefit from closer monitoring and early intervention. While there is literature on intraoperative blood pressure, there are limited studies examining pre- and postoperative blood pressure.

Aims

Cementing in arthroplasty for hip fracture is associated with improved postoperative function, but may have an increased risk of early mortality compared to uncemented fixation. Quantifying this mortality risk is important in providing safe patient care. This study investigated the association between cement use in arthroplasty and mortality at 30 days and one year in patients aged 50 years and over with hip fracture.

Aims

Total hip arthroplasty (THA) is considered the preferred treatment for displaced proximal femoral neck fractures. However, in many countries this option is economically unviable. To improve outcomes in financially disadvantaged populations, we studied the technique of concomitant valgus hip osteotomy and operative fixation (VOOF). This prospective serial study compares two treatment groups: VOOF versus operative fixation alone with cannulated compression screws (CCSs).

Aims

Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI.

Studies describing the effect of body mass index (BMI) on the outcome of total hip replacement have been inconclusive and contradictory. We examined the effect of BMI on medium-term outcome in a cohort of 1617 patients who underwent a primary total hip replacement for osteoarthritis. These patients were followed prospectively for five years with the outcomes of dislocation, revision, duration of surgery and deep and superficial infection studied, as well as collecting Harris hip scores (HHS) and Short-Form 36 (SF-36) questionnaires pre-operatively and at review. A multivariate analysis was performed to see whether BMI is an independent predictor of poor outcome. We found that patients with a BMI of ? 35 kg/m. 2. have a 4.42 times higher rate of dislocation than those with a BMI < 25 kg/m. 2. Increasing BMI is also associated with superficial infection and poorer HHS and SF-36 scores at five years. These trends remain significant even when multivariate analysis adjusts for age, gender, prosthesis, operating consultant, pre-operative HHS and SF-36, and comorbidities including diabetes mellitus, cardiac disease and osteoporosis. Despite the increased risks, the five-year outcome scores indicate that obese patients have much to gain from total hip replacement. Thus total hip replacement should not be withheld from patients solely on the grounds of an elevated BMI. However, longer-term follow-up of this cohort is required to establish whether adverse outcomes become more evident with time

Aims

A recent report from France suggested an association between the use of cobalt-chrome (CoCr) femoral heads in total hip arthroplasties (THAs) and an increased risk of dilated cardiomyopathy and heart failure. CoCr is a commonly used material in orthopaedic implants. If the reported association is causal, the consequences would be significant given the millions of joint arthroplasties and other orthopaedic procedures in which CoCr is used annually. We examined whether CoCr-containing THAs were associated with an increased risk of all-cause mortality, heart outcomes, cancer, and neurodegenerative disorders in a large national database.