The effect of a manufacturer recall on the threshold to revise a metal-on-metal hip

Purpose

Management of the unexplained, painful large diameter metal-on-metal (MOM) hip replacement is difficult. Although there are guidelines for surgeons, there is no clear documented evidence describing the overall threshold for revision surgery. The 2010 product recall of the DePuy Articular Surface Replacement (ASR) and subsequent media coverage may have increased patient and surgeon apprehension, resulting in earlier intervention, i.e. at a greater Oxford hip score (OHS) than expected. Our aim was to investigate whether the threshold for revision using known parameters was affected by the ASR recall. These parameters include poor clinical results (persistent pain or mechanical symptoms), pseudotumour or other progressive soft tissue involvement, osteolysis and high or rising metal ion levels.

Methods

We used our national referral database of MOM hips, which were revised between 2008 and 2012. Once inclusion and exclusion criteria were applied, we identified 240 patients—71 patients in the pre-recall group and 169 patients in the post-recall group.

Results

The ASR product recall did not seem to affect the threshold for revision of a MOM hip, with no significant difference between the two groups in terms of the functional (median OHS = 17 pre-recall and 20 post-recall; p?=?0.2109) and radiological (median inclination angle = 50 pre-recall and 48 post-recall; p?=?0.3221) markers used to guide management. We did however discover that blood metal ion levels were higher in the post-recall group.

Conclusion

Issue of a product recall did not change the hip function threshold for revision surgery. The decision to revise a metal-on-metal hip is complex and should follow published guidelines, encompassing metal ion measurement and cross-sectional imaging where appropriate.     

Hip arthroplasty with the articular surface replacement (ASR) system: survivorship analysis and functional outcomes

Background

The articular surface replacement (ASR) hip resurfacing system, now withdrawn, has the highest all-cause revision rate (24.2 % at 7 years) compared with other resurfacing brands. We present our experience with the ASR articulation and the implant recall process.

Methods

We reviewed the medical records and examined all 55 patients (57 hips) who had THA by the senior author between March 2005 and November 2008. We recorded the Oxford Hip scores, metal ion levels, need for revision, the indication for revision, and the intra-operative findings. Radiographs were performed at the time of recall to detect component failure.

Results

Survival at 5 years with revision for any reason as the endpoint was 85.1 % for all patients. At the time of recall, 10 (17.5 %) of fifty-seven THAs were already revised. Four (40 %) of the ten revisions were performed within 1 month of the operation due to a periprosthetic fracture. Three other revisions were due to avascular necrosis at a mean time of 3.6 years. One patient was revised due to infection. The two remaining revisions were due to ongoing groin pain, in one of whom the cup was found to be loose.

Conclusions

Our data indicate an overall high revision rate, comparable with recently published studies. Even though most of our revisions were attributed to causes that are not specific to the metal-on-metal articulation, we do expect to find more cases of failures in the future. Therefore, continued close clinical surveillance and laboratory monitoring of these patients is warranted.     

Impact of Raised Serum Cobalt Levels From Recalled Articular Surface Replacement Hip Prostheses on the Visual Pathway

Background

The articular surface replacement (ASR) was recalled in 2010 because of higher than expected revision rates. Patients reported symptoms of neurologic dysfunction including poor vision. This cohort study, using objective measurements, aimed to establish whether a higher incidence of visual function defects exists in ASR patients.

Metal-on-metal surface hip arthroplasty in patients with abnormal Coxanatomy: preliminary results

The purpose of this study was to evaluate early to intermediate results of metal-on-metal (MoM) hip resurfacing arthroplasty in patients with abnormal hip anatomy. We evaluated nine MoM hip resurfacing arthroplasty in eight patients with abnormal coxanatomy performed at a district general hospital in the UK between March 1999 and November 2002. One patient had undergone bilateral sequential hip resurfacing procedure. These patients were defined to have abnormal coxanatomy by virtue of previous dysplastic disease of hip in three cases, previous Legg-Calve-Perthes disease, multiple epiphyseal dysplasia, T cell acute lymphoblastic leukaemia, trauma and sepsis in one case each. The mean follow-up was 40.8 months. The mean age at primary operation was 35 years (range: minimum 21 years; maximum 44 years). There were six male and two female patients. There were six right-sided and three left-sided procedures. All patients had satisfactory outcomes. There were no deep infections, dislocations, or femoral neck fractures. Although this is a short series, MoM resurfaced hips with appropriate case selection can yield satisfactory short-term to intermediate-term results in the young and active patients with abnormal hip anatomy.     

Interstitial cystitis/painful bladder syndrome: the influence of modern diagnostic criteria on epidemiology and on Internet search activity by the public

Interstitial cystitis/painful bladder syndrome (IC/PBS) is a chronic debilitating condition that is characterised by suprapubic pain and urinary symptoms such as urgency, nocturia and urinary frequency. The prevalence of the condition is increasing due to more inclusive diagnostic criteria. Herein, we review the evolving epidemiology of IC/PBS and investigate health seeking behaviour for the condition through Internet search activity. Study selection was performed in accordance with PRISMA. In addition, global search trends for the terms ‘Interstitial Cystitis’ and ‘Painful Bladder Syndrome’ from 2005 to 2015 were also evaluated using the ‘Google Trends’ search application. The mean search activity per month was recorded and mean activity at annual intervals calculated. Regional search activity by country and city was also measured. Prevalence rates for IC/PBS vary according to diagnostic criteria and range from 2% to 17.3% among the general population. Increased prevalence is associated with female gender and females with one first-degree relative affected. There has been an increase in global mean search activity for IC/PBS on an annual basis since 2005. The greatest increase in search activity was in USA, Canada, United Kingdom, Australia, Ireland and India respectively. The top five cities for search activity for IC/PBS were in the USA. As diagnostic criteria for IC/PBS continues to become more inclusive it is likely that the prevalence will continue to increase. This is particularly true for the USA and Canada as these regions have demonstrated the greatest increase in Internet search activity for IC/ PBS.     

Attitudes of anaesthetists to awareness and depth of anaesthesia monitoring in the UK

BACKGROUND AND OBJECTIVE: Awareness with postoperative recall of intraoperative events is a rare but serious complication of general anaesthesia. This survey investigated the attitude of anaesthetists in the UK to awareness and depth of anaesthesia monitoring. METHODS: Questionnaires were sent to 4927 consultant anaesthetists in 285 hospitals in the UK in September 2004. The responses were recorded in an electronic database, summarized and compared with the results of studies performed in Australia and the USA. RESULTS: The response rate was 44%. When judged against published awareness rates, anaesthetists underestimated the incidence of awareness in their own practice (median 1: 5000). One-third of respondents have dealt with patients who have experienced intraoperative recall. The majority of anaesthetists perceived awareness as a minor problem on an 11-point scale (modal score 2, median score 3, IQR 2-5). Eighty-six percent of anaesthetists considered clinical signs unreliable but 91% felt that measurement of end-tidal anaesthetic agent concentration reduces the likelihood of awareness. The majority of anaesthetists would use a monitor at least some of the time if one was available to them. Overall, the attitudes of anaesthetists in the UK, USA and Australia are remarkably similar. CONCLUSIONS: Anaesthetists tend not to view awareness as a serious problem. Although most accept that clinical signs are unreliable indicators of awareness, few believe that monitors of anaesthetic depth should be used for routine cases.     

A systematic review and meta-analysis evaluating the role of laparoscopic surgical resection of transverse colon tumours

Objectives

A meta-analysis of published literature comparing outcomes after laparoscopic resection (LR) with open resection (OR) for transverse colon tumours.

Methods

Medline, PubMed, CINAHL, EMBASE and Cochrane were searched from inception to October 2013. The text words “minimally invasive”, “keyhole surgery” and “transverse colon” were used in combination with the medical subject headings “laparoscopy” and “colon cancer”. Outcome variables were chosen based upon whether the included articles reported results. A meta-analysis was performed to obtain a summative outcome.

Results

Six comparatives involving 444 patients were analysed. Of them 245 patients were in the LR group and 199 in the OR group. There was a significant increase in operative time in the LR group compared with the OR group [random effects model: SMD = ?0.65, 95 % CI (?1.01, ?0.30), z = ?3.60, p < 0.001] but there was significant heterogeneity amongst trials (Q = 15.51, df = 5, p = 0.008, I ² = 68). There was less blood loss in the LR group [fixed effects model: SMD = 0.70, 95 % CI (0.47, 0.93), z = 6.01, p < 0.001] and patients returned to oral diet earlier [random effects model: SMD = 0.78, 95 % CI (0.40, 1.16), z = 4.01, p < 0.001] and had a reduced time to functioning bowel [fixed effects model: SMD = 0.86, 95 % CI (0.60, 1.11), z = 6.63, p < 0.001]. No difference was seen for overall morbidity (p = 0.76) or mortality (p = 0.58).

Conclusions

LR of transverse colon tumours is a safe and effective technique. Although there is an increase in operating time, operative and clinical outcomes of intraoperative blood loss and faster recovery are seen with laparoscopic procedures.     

Excess risk of hip fractures attributable to the use of antidepressants in five European countries and the USA

Summary

The association between antidepressant use and hip fracture remains unclear. We conducted a systematic review to estimate Population Attributable Risks (PAR) for France, Germany, Italy, Spain, UK, and the USA. We report a heterogeneous prevalence of antidepressant use and related PARs, both lowest for Italy and highest for the USA.

Introduction

Antidepressant use has been associated with an increased hip fracture risk in observational studies. However, the potential contribution of antidepressant consumption on the population rate of hip fractures has not been described. Our aim was to estimate the impact of the use of different classes of antidepressants on the rate of hip fracture at a population-level in France, Germany, Italy, Spain, the UK, and the USA.

Methods

We conducted a systematic literature review to estimate the pooled relative risk (RR) of hip fracture according to use of antidepressants. Prevalence rates of antidepressant use (Pe) in 2009 were calculated for each country using the The Intercontinental Medical Statistics database and three public databases from Denmark, the Netherlands, and Norway. Both the RR and Pe were used to calculate PAR of hip fractures associated with antidepressant use.

Results

The literature review showed an increased risk of hip fractures in antidepressant users (RR, 1.7; 95 % confidence interval (CI), 1.5–2.0). Rates of antidepressant use showed considerable differences between countries, ranging from 4.4 % (Italy) to 11.2 % (USA) in the year 2009. The estimated PAR of antidepressants on hip fracture rates were 3.0 % (95 % CI, 2.0–4.1; Italy), 3.1 % (95 % CI, 2.1–4.3; Germany), 3.8 % (95 % CI, 2.6–5.3; France), 4.8 % (95 % CI, 3.3–6.5; Spain), 4.9 % (95 % CI, 3.4–6.8; UK), and 7.2 % (95 % CI, 5.0–9.9; USA). PARs differed for different types of antidepressants, with highest attributable risks for selective serotonin reuptake inhibitors.

Conclusions

These findings suggest that the potential contribution of antidepressant use to the population rate of hip fractures in the five large EU countries and the USA varies between 3 and 7 %.     

Indications for MARS-MRI in Patients Treated With Metal-on-Metal Hip Resurfacing Arthroplasty

Background

Currently, there are no universally accepted guidelines on when to obtain metal artifact reduction sequence magnetic resonance imaging (MARS-MRI) in metal-on-metal (MoM) hip resurfacing arthroplasty (HRA) patients. Our primary aims were to identify which patient and clinical factors are predictive of adverse local tissue reaction (ALTR) and create an algorithm for indicating MARS-MRI in patients with Articular Surface Replacement (ASR) HRA. The secondary aim was to compare our algorithm to existing guidelines on when to perform MARS-MRI in MoM HRA patients.

Methods of abdominal wall expansion for repair of incisional herniae: a systematic review

Aim

To systematically review the available literature regarding methods for abdominal wall expansion and compare the outcome of primary fascial closure rates.

Methods

A systematic search of Pubmed and Embase databases was conducted using the search terms “Abdominal wall hernia”, “ventral hernia”, “midline hernia”, “Botulinum toxin”, “botox”, “dysport”, “progressive preoperative pneumoperitoneum”, and “tissue expanders”. Study quality was assessed using the Methodological Index for Non-Randomised Studies.

Results

21 of the105 studies identified met the inclusion criteria. Progressive preoperative pneumoperitoneum (PPP) was performed in 269 patients across 15 studies with primary fascial closure being achieved in 226 (84 %). 16 patients had a recurrence (7.2 %) and the complication rate was 12 % with 2 reported mortalities. There were 4 studies with 14 patients in total undergoing abdominal wall expansion using tissue expanders with a fascial closure rate of 92.9 % (n = 13). A recurrence rate of 10.0 % (n = 1) was reported with 1 complication and no mortalities. Follow up ranged from 3 to 36 months across the studies. There were 2 studies reporting the use of botulinum toxin with 29 patients in total. A primary fascial closure rate of 100 % (n = 29) was demonstrated although a combination of techniques including component separation and Rives-Stoppa repair were used. There were no reported complications related to the use of Botulinum Toxin. However, the short-term follow up in many cases and the lack of routine radiological assessment for recurrence suggests that the recurrence rate has been underestimated.

Conclusions

PPP, tissue expanders and Botulinum toxin are safe and feasible methods for abdominal wall expansion prior to incisional hernia repair. In combination with existing techniques for repair, these methods may help provide the crucial extra tissue mobility required to achieve primary closure.

     

Trends in internet search activity,media coverage,and patient-centered health information after the FDA safety communications on surgical mesh for pelvic organ prolapse

Introduction

In July 2011, the US Food and Drug Administration (FDA) issued a safety communication regarding serious complications associated with surgical mesh for pelvic organ prolapse, prompting increased media and public attention. This study sought to analyze internet search activity and news article volume after this FDA warning and to evaluate the quality of websites providing patient-centered information.

Methods

Google Trends? was utilized to evaluate search engine trends for the term “pelvic organ prolapse” and associated terms between 1 January 2004 and 31 December 2014. Google News? was utilized to quantify the number of news articles annually under the term “pelvic organ prolapse.” The search results for the term “pelvic organ prolapse” were assessed for quality using the Health On the Net Foundation (HON) certification.

Results

There was a significant increase in search activity from 37.42 in 2010 to 57.75 in 2011, at the time of the FDA communication (p?=?0.021). No other annual interval had a statistically significant increase in search activity. The single highest monthly search activity, given the value of 100, was August 2011, immediately following the July 2011 notification, with the next highest value being 98 in July 2011. Linear regression analysis of news articles per year since the FDA communication revealed r²?=?0.88, with a coefficient of 186. Quality assessment demonstrated that 42 % of websites were HON-certified, with .gov sites providing the highest quality information.

Conclusions

Although the 2011 FDA safety communication on surgical mesh was associated with increased public and media attention, the quality of relevant health information on the internet remains of poor quality. Future quality assurance measures may be critical in enabling patients to play active roles in their own healthcare.

     

Survivorship,Patient Reported Outcome and Satisfaction Following Resurfacing and Total Hip Arthroplasty

Resurfacing (RA) and total hip arthroplasty (THA) are options in the treatment of debilitating hip pathology. 381 patients that had undergone arthroplasty with a BHR RA, ASR RA, metal-on-metal (MoM) THA or ceramic-on-ceramic (CoC) THA were reviewed for satisfaction, function, health and survivorship at a median follow up of 50 months. Significantly lower survivorship for revision and reoperation was observed in the ASR group. The BHR and CoC demonstrated better outcome scores than the ASR (OHS and SAPS) and the BHR better scores than the MoM (OHS and SF12 PCS). In the short to medium term, survivorship and outcomes for the best performing RA (BHR) and THA (CoC) were comparable. There was a non-significant trend towards poorer outcome scores in the MoM THA group.     

Results of metal-on-metal hip resurfacing in patients 40 years old and younger

The prevalence of total hip arthroplasty in young patients is small but increasing. We analyzed the results of metal-on-metal hip resurfacing (MMHR) in patients aged 40 years or less. In total 74 operations were performed on 64 patients. Mean age at operation was 33.2 years. HHS averaged 92.3 points at latest follow-up, mean UCLA activity was 8.2. Patients with comorbidity evinced lower scores in HHS, in UCLA activity and in quality of life than patients without comorbidities. Eight revisions (10.8 %) were performed, of which seven due to adverse reaction to metal debris. Seven-year survival was 90.5 %. The functional outcome of hip resurfacing in this cohort was excellent, but overall survival was unsatisfactory. Further analysis is required to verify the role of hip resurfacing among young and active patients.     

Inferomedial Hip Center Decreases Failure Rates in Cementless Total Hip Arthroplasty for Crowe II and III Hip Dysplasia

Background

We sought to evaluate the outcomes of cementless acetabular components used in patients with Crowe II and III dysplasia, and to compare outcomes between cups placed within vs outside of an “anatomic” zone. Our specific aims were to (1) plot hip centers in these patients at our institution to characterize “anatomic” vs “nonanatomic” positions, (2) evaluate the association between hip center and radiographic loosening, (3) determine whether hip center was associated with acetabular component revision, and (4) compare patient-reported outcome scores between groups.

Forecasting the burden of future postmenopausal hip fractures

Summary

A growing elderly population is expected worldwide, and the rate of hip fractures is decisive for the future fracture burden. Significant declines in hip fracture rates in Norway, the USA, France, Germany, and the UK are required to counteract the impact of the ageing effects.

Introduction

This study aims to evaluate the consequences of the expected growth of the elderly population worldwide on the hip fracture burden using Norway as an example. Furthermore, we wanted to estimate the decline in hip fracture rates required to counteract the anticipated increase in the burden of hip fracture for Norway, the USA, France, Germany, and the UK.

Methods

The burden of future postmenopausal hip fractures in Norway were estimated given (1) constant age-specific rates, (2) continued decline, and (3) different cohort scenarios. Based on population projection estimates and population age-specific hip fracture rates in women 65 years and older, we calculated the required declines in hip fracture rates needed to counteract the growing elderly populations in Norway, the USA, France, Germany, and the UK.

Results

The level of age-specific hip fracture rates had a huge impact on the future hip fracture burden in Norway. Even if the hip fracture rates decline at the same speed, a 22 % increase in the burden of hip fractures can be expected by 2040. An annual decline in hip fracture rates of 1.1–2.2 % until 2040 is required to counteract the effects of the growing elderly population on the future burden of hip fractures in Norway, the USA, France, Germany, and the UK.

Conclusions

Hip fracture rates have a great impact on the burden of hip fractures. The rates will have to decline significantly to counteract the impact of a growing elderly population. A change in preventive strategies and further studies are warranted to identify the complex causes associated to hip fractures.     

A comparison of explanted Articular Surface Replacement and Birmingham Hip Resurfacing components

The Articular Surface Replacement (ASR) hip resurfacing arthroplasty has a failure rate of 12.0% at five years, compared with 4.3% for the Birmingham Hip Resurfacing (BHR). We analysed 66 ASR and 64 BHR explanted metal-on-metal hip replacements with the aim of understanding their mechanisms of failure. We measured the linear wear rates of the acetabular and femoral components and analysed the clinical cause of failure, pre-revision blood metal ion levels and orientation of the acetabular component. There was no significant difference in metal ion levels (chromium, p = 0.82; cobalt, p = 0.40) or head wear rate (p = 0.14) between the two groups. The ASR had a significantly increased rate of wear of the acetabular component (p = 0.03) and a significantly increased occurrence of edge loading (p < 0.005), which can be attributed to differences in design between the ASR and BHR. The effects of differences in design on the in vivo wear rates are discussed: these may provide an explanation as to why the ASR is more sensitive to suboptimal positioning than the BHR.     

Implication of Femoral Stem on Performance of Articular Surface Replacement (ASR) XL Total Hip Arthroplasty

Taper junctions of large diameter metal-on-metal femoral heads and femoral stems were described as metal ion generator due to accelerated wear and corrosion. However, literature about the Articular Surface Replacement (ASR) total hip arthroplasty (THA) invariably deals with stems manufactured by DePuy Orthopedics (Warsaw, IN, USA). Nothing is known whether different stems with common 12/14 mm tapers affect failure rate or ion release. 99 ASR THA (88 patients) implanted with CoxaFit or ARGE Geradschaft stems (K-Implant, Hannover, Germany) were retrospectively analyzed. After a mean follow-up of 3.5 years revision rate was 24.5%, mostly due to adverse reaction to metal debris (ARMD). CT scan revealed component loosening in 10.3% and pseudotumoral lesions in 12.6%. Elevated ion concentrations (> 7 μg/l) were found in 38.6%.