Aims. Head-taper corrosion is a cause of failure in total hip arthroplasty (THA). Recent reports have described an increasing number of V40 taper failures with
Adverse reaction to wear and corrosion debris
is a cause for concern in total hip arthroplasty (THA). Modular junctions
are a potential source of such wear products and are associated
with secondary pseudotumour formation. We present a consecutive series of 17 patients treated at our
unit for this complication following metal-on-highly cross-linked
polyethylene (MoP) THA. We emphasise the risk of misdiagnosis as
infection, and present the aggregate laboratory results and pathological
findings in this series. The clinical presentation was pain, swelling or instability.
Solid, cystic and mixed soft-tissue lesions were noted on imaging
and confirmed intra-operatively. Corrosion at the head–neck junction
was noted in all cases. No bacteria were isolated on multiple pre-
and intra-operative samples yet the mean erythrocyte sedimentation
rate was 49 (9 to 100) and C-reactive protein 32 (0.6 to 106) and
stromal polymorphonuclear cell counts were noted in nine cases. Adverse soft–tissue reactions can occur in MoP THA owing to corrosion
products released from the head–neck junction. The diagnosis should
be carefully considered when investigating pain after THA. This
may avoid the misdiagnosis of periprosthetic infection with an unidentified
organism and mitigate the unnecessary management of these cases
with complete single- or two-stage exchange. Cite this article:
Fretting and corrosion at the modular head/neck junction, known
as trunnionosis, in total hip arthroplasty (THA) is a cause of adverse
reaction to metal debris (ARMD). We describe the outcome of revision
of metal-on-polyethylene (MoP) THA for ARMD due to trunnionosis
with emphasis on the risk of major complications. A total of 36 patients with a MoP THA who underwent revision
for ARMD due to trunnionosis were identified. Three were excluded
as their revision had been to another metal head. The remaining
33 were revised to a ceramic head with a titanium sleeve. We describe
the presentation, revision findings, and risk of complications in
these patients.Aims
Patients and Methods
Aims. The purpose of this study is to examine six types of bearing surfaces implanted at a single institution over three decades to determine whether the reasons for revision vary among the groups and how long it takes to identify differences in survival. Methods. We considered six cohorts that included a total of 1,707 primary hips done between 1982 and 2010. These included 223 conventional polyethylene sterilized with γ irradiation in air (CPE-GA), 114 conventional polyethylene sterilized with gas plasma (CPE-GP), 116 crosslinked polyethylene (XLPE), 1,083 metal-on-metal (MOM), 90 ceramic-on-ceramic (COC), and 81 surface arthroplasties (SAs). With the exception of the COC, all other groups used cobalt-chromium (CoCr) femoral heads. The mean follow-up was 10 (0.008 to 35) years. Descriptive statistics with revisions per 100 component years (re/100 yr) and survival analysis with revision for any reason as the endpoint were used to compare bearing surfaces. Results. XLPE liners demonstrated a lower cumulative incidence of revision at 15 years compared to the CPE-GA and CPE-GP groups owing to the absence of wear-related revisions (4% for XLPE vs 18%, p = 0.02, and 15%, p = 0.003, respectively). Revisions for
Aims. Advances in surgical technique and implant design may influence the incidence and mechanism of failure resulting in revision total hip arthroplasty (rTHA). The purpose of the current study was to characterize aetiologies requiring rTHA, and to determine whether temporal changes existed in these aetiologies over a ten-year period. Methods. All rTHAs performed at a single institution from 2009 to 2019 were identified. Demographic information and mode of implant failure was obtained for all patients. Data for rTHA were stratified into two time periods to assess for temporal changes: 2009 to 2013, and 2014 to 2019. Operative reports, radiological imaging, and current procedural terminology (CPT) codes were cross-checked to ensure the accurate classification of revision aetiology for each patient. Results. In all, 2,924 patients with a mean age of 64.6 years (17 to 96) were identified. There were 1,563 (53.5%) female patients, and the majority of patients were Caucasian (n = 2,362, 80.8%). The three most frequent rTHA aetiologies were infection (27.2%), aseptic loosening (25.2%), and wear (15.2%). The frequency of rTHA for
Aims.
Aims. Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is
Aims. Modular dual-mobility constructs reduce the risk of dislocation after revision total hip arthroplasty (THA). However, questions about metal ions from the cobalt-chromium (CoCr) liner persist, and are particularly germane to patients being revised for
Aims. We present a case series of ten metal-on-polyethylene total hip
arthroplasties (MoP THAs) with delayed dislocation associated with
unrecognised
Dislocation remains among the most common complications
of, and reasons for, revision of both primary and revision total
hip replacements (THR). Hence, there is great interest in maximising
stability to prevent this complication. Head size has been recognised
to have a strong influence on the risk of dislocation post-operatively.
As femoral head size increases, stability is augmented, secondary
to an increase in impingement-free range of movement. Larger head
sizes also greatly increase the ‘jump distance’ required for the
head to dislocate in an appropriately positioned cup. Level-one
studies support the use of larger diameter heads as they decrease
the risk of dislocation following primary and revision THR. Highly cross-linked
polyethylene has allowed us to increase femoral head size, without
a marked increase in wear. However, the thin polyethylene liners
necessary to accommodate larger heads may increase the risk of liner
fracture and larger heads have also been implicated in causing soft-tissue
impingement resulting in groin pain. Larger diameter heads also
impart larger forces on the femoral trunnion, which may contribute
to corrosion, metal release, and
Whitehouse MR, Endo M, Zachara S, Nielsen TO,
Greidanus NV, Masri BA, Garbuz DS, Duncan CP.
Objectives. Hips with metal-on-metal total hip arthroplasty (MoM THA) have a high rate of
The use of large-diameter metal-on-metal (MoM)
components in total hip arthroplasty (THA) is associated with an increased
risk of early failure due to
Large-head metal-on-metal (MoM) total hip replacements
(THR) have given rise to concern. Comparative studies of small-head
MoM THRs over a longer follow-up period are lacking. Our objective
was to compare the incidence of complications such as infection,
dislocation, revision,
There is little information in the literature about the use of dual-mobility (DM) bearings in preventing re-dislocation in revision total hip arthroplasty (THA). The aim of this study was to compare the use of DM bearings, standard bearings, and constrained liners in revision THA for recurrent dislocation, and to identify risk factors for re-dislocation. We reviewed 86 consecutive revision THAs performed for dislocation between August 2012 and July 2019. A total of 38 revisions (44.2%) involved a DM bearing, while 39 (45.3%) and nine (10.5%) involved a standard bearing and a constrained liner, respectively. Rates of re-dislocation, re-revision for dislocation, and overall re-revision were compared. Radiographs were assessed for the positioning of the acetabular component, the restoration of the centre of rotation, leg length, and offset. Risk factors for re-dislocation were determined by Cox regression analysis. The modified Harris Hip Scores (mHHSs) were recorded. The mean age of the patients at the time of revision was 70 years (43 to 88); 54 were female (62.8%). The mean follow-up was 5.0 years (2.0 to 8.75).Aims
Methods
This study evaluated the definitions developed by the European Bone and Joint Infection Society (EBJIS) 2021, the International Consensus Meeting (ICM) 2018, and the Infectious Diseases Society of America (IDSA) 2013, for the diagnosis of periprosthetic joint infection (PJI). In this single-centre, retrospective analysis of prospectively collected data, patients with an indicated revision surgery after a total hip or knee arthroplasty were included between 2015 and 2020. A standardized diagnostic workup was performed, identifying the components of the EBJIS, ICM, and IDSA criteria in each patient.Aims
Methods
The December 2022 Hip & Pelvis Roundup360 looks at: Fix and replace: simultaneous fracture fixation and hip arthroplasty for acetabular fractures in older patients; Is the revision rate for femoral neck fracture lower for total hip arthroplasty than for hemiarthroplasty?; Femoral periprosthetic fractures: data from the COMPOSE cohort study; Dual-mobility cups and fracture of the femur; What’s the deal with outcomes for hip and knee arthroplasty outcomes internationally?; Osteochondral lesions of the femoral head: is costal cartilage the answer?
The first aim of this study was to evaluate whether preoperative renal function is associated with postoperative changes in whole blood levels of metal ions in patients who have undergone a Birmingham Hip Resurfacing (BHR) arthroplasty with a metal-on-metal bearing. The second aim was to evaluate whether exposure to increased cobalt (Co) and chromium (Cr) levels for ten years adversely affected renal function. As part of a multicentre, prospective post-approval study, whole blood samples were sent to a single specialized laboratory to determine Co and Cr levels, and the estimated glomerular filtration rate (eGFR). The study included patients with 117 unrevised unilateral BHRs. There were 36 females (31%). The mean age of the patients at the time of surgery of 51.3 years (SD 6.5), and they all had preoperative one-, four-, five-, and ten-year laboratory data. The mean follow-up was 10.1 years (SD 0.2).Aims
Methods
Modular dual-mobility (DM) articulations are increasingly used during total hip arthroplasty (THA). However, concerns remain regarding the metal liner modularity. This study aims to correlate metal artifact reduction sequence (MARS)-MRI abnormalities with serum metal ion levels in patients with DM articulations. A total of 45 patients (50 hips) with a modular DM articulation were included with mean follow-up of 3.7 years (SD 1.2). Enrolled patients with an asymptomatic, primary THA and DM articulation with over two years’ follow-up underwent MARS-MRI. Each patient had serum cobalt, chromium, and titanium levels drawn. Patient satisfaction, Oxford Hip Score, and Forgotten Joint Score-12 (FJS-12) were collected. Each MARS-MRI was independently reviewed by fellowship-trained musculoskeletal radiologists blinded to serum ion levels.Aims
Methods
The aim of this study was to evaluate the optimal deep tissue specimen sample number for histopathological analysis in the diagnosis of periprosthetic joint infection (PJI). In this retrospective diagnostic study, patients undergoing revision surgery after total hip or knee arthroplasty (n = 119) between January 2015 and July 2018 were included. Multiple specimens of the periprosthetic membrane and pseudocapsule were obtained for histopathological analysis at revision arthroplasty. Based on the Infectious Diseases Society of America (IDSA) 2013 criteria, the International Consensus Meeting (ICM) 2018 criteria, and the European Bone and Joint Infection Society (EBJIS) 2021 criteria, PJI was defined. Using a mixed effects logistic regression model, the sensitivity and specificity of the histological diagnosis were calculated. The optimal number of periprosthetic tissue specimens for histopathological analysis was determined by applying the Youden index.Aims
Methods
The aims of this study were to determine if an increasing serum cobalt (Co) and/or chromium (Cr) concentration is correlated with a decreasing Harris Hip Score (HHS) and Hip disability and Osteoarthritis Outcome Score (HOOS) in patients who received the Articular Surface Replacement (ASR) hip resurfacing arthroplasty (HRA), and to evaluate the ten-year revision rate and show if sex, inclination angle, and Co level influenced the revision rate. A total of 62 patients with an ASR-HRA were included and monitored yearly postoperatively. At follow-up, serum Co and Cr levels were measured and the HHS and the HOOS were scored. In addition, preoperative patient and implant variables and the need for revision surgery were recorded. We used a linear mixed model to relate the serum Co and Cr levels to different patient-reported outcome measures (PROMs). For the survival analyses we used the Kaplan-Meier and Cox regression model.Aims
Methods
This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection. A total of 1,171 total hip arthroplasty (THA) patients with MoM articulations from August 2000 to March 2014 were retrospectively identified. Of those, 328 patients underwent metal artefact reduction sequence MRI and had minimum two years’ clinical follow-up, and met our inclusion criteria. Data collected included demographic details, surgical indication, laterality, implants used, history of pseudotumour, and their corresponding preoperative ESR (mm/hr) and CRP (mg/dl) levels. Multivariate logistic regression modelling was used to evaluate PJI and history of pseudotumour, and receiver operating characteristic curves were created to assess the diagnostic capabilities of ESR and CRP to determine the presence of infection in patients undergoing revision surgery.Aims
Methods
Metal allergy in knee arthroplasty patients is a controversial topic. We aimed to conduct a scoping review to clarify the management of metal allergy in primary and revision total knee arthroplasty (TKA). Studies were identified by searching electronic databases: Cochrane Central Register of Controlled Trials, Ovid MEDLINE, and Embase, from their inception to November 2020, for studies evaluating TKA patients with metal hypersensitivity/allergy. All studies reporting on diagnosing or managing metal hypersensitivity in TKA were included. Data were extracted and summarized based on study design, study population, interventions and outcomes. A practical guide is then formulated based on the available evidence.Aims
Methods
Modular dual mobility (MDM) acetabular components are often used with the aim of reducing the risk of dislocation in revision total hip arthroplasty (THA). There is, however, little information in the literature about its use in this context. The aim of this study, therefore, was to evaluate the outcomes in a cohort of patients in whom MDM components were used at revision THA, with a mean follow-up of more than five years. Using the database of
a single academic centre, 126 revision THAs in 117 patients using a single
design of an MDM acetabular component were retrospectively reviewed. A total of 94 revision THAs in 88 patients with a mean follow-up of 5.5 years were included in the study. Survivorship was analyzed with the endpoints of dislocation, reoperation for dislocation, acetabular revision for aseptic loosening, and acetabular revision for any reason. The secondary endpoints were surgical complications and the radiological outcome.Aims
Methods
Dual mobility implants in total hip arthroplasty are designed to increase the functional head size, thus decreasing the potential for dislocation. Modular dual mobility (MDM) implants incorporate a metal liner (e.g. cobalt-chromium alloy) in a metal shell (e.g. titanium alloy), raising concern for mechanically assisted crevice corrosion at the modular liner-shell connection. We sought to examine fretting and corrosion on MDM liners, to analyze the corrosion products, and to examine histologically the periprosthetic tissues. A total of 60 retrieved liners were subjectively scored for fretting and corrosion. The corrosion products from the three most severely corroded implants were removed from the implant surface, imaged using scanning electron microscopy, and analyzed using Fourier-transform infrared spectroscopy.Aims
Methods
A limited number of investigations with conflicting results have described perivascular lymphocytic infiltration (PVLI) in the setting of total knee arthroplasty (TKA). The purpose of this study was to determine if PVLI found in TKAs at the time of aseptic revision surgery was associated with worse clinical outcomes and survivorship. A retrospective review was conducted on 617 patients who underwent aseptic TKA revision who had histological analysis for PVLI at the time of surgery. Clinical and radiological data were obtained pre- and postoperatively, six weeks postoperatively, and then every year thereafter.Aims
Methods
Dual mobility (DM) implants have been shown to reduce the dislocation rate after total hip arthroplasty (THA), but there remain concerns about the use of cobalt chrome liners inserted into titanium shells. The aim of this study was to assess the clinical outcomes, metal ion levels, and periprosthetic femoral bone mineral density (BMD) at mid-term follow-up in young, active patients receiving a modular DM THA. This was a prospective study involving patients aged < 65 years, with a BMI of < 35 kg/m2, and University of California, Los Angeles activity score of > 6 who underwent primary THA with a modular cobalt chrome acetabular liner, highly cross-linked polyethylene mobile bearing, and a cementless titanium femoral stem. Patient-reported outcome measures, whole blood metal ion levels (μg/l), and periprosthetic femoral BMD were measured at baseline and at one, two, and five years postoperatively. The results two years postoperatively for this cohort have been previously reported.Aims
Methods
This study compared the cobalt and chromium serum ion concentration of patients treated with two different metal-on-metal (MoM) hinged total knee arthroplasty (TKA) systems, as well as a titanium nitride (TiN)-coated variant. A total of 63 patients (65 implants) were treated using either a MoM-coated (n = 29) or TiN-coated (n = 7) hinged TKA (GenuX mobile bearing, MUTARS; Implantcast, Germany) versus the BPKS (Brehm, Germany) hinged TKA (n = 27), in which the weight placed on the MoM hinge is diffused through a polyethylene (PE) inlay, reducing the direct load on the MoM hinge. Serum cobalt and chromium ion concentrations were assessed after minimum follow-up of 12 months, as well as functional outcome and quality of life.Aims
Methods
To establish the survivorship, function, and metal ion levels in an unselected series of metal-on-metal hip resurfacing arthroplasties (HRAs) performed by a non-designer surgeon. We reviewed 105 consecutive HRAs in 83 patients, performed by a single surgeon, at a mean follow-up of 14.9 years (9.3 to 19.1). The cohort included 45 male and 38 female patients, with a mean age of 49.5 years (SD 12.5)Aims
Methods
Prior studies have identified that malseating of a modular dual mobility liner can occur, with previous reported incidences between 5.8% and 16.4%. The aim of this study was to determine the incidence of malseating in dual mobility implants at our institution, assess for risk factors for liner malseating, and investigate whether liner malseating has any impact on clinical outcomes after surgery. We retrospectively reviewed the radiographs of 239 primary and revision total hip arthroplasties with a modular dual mobility liner. Two independent reviewers assessed radiographs for each patient twice for evidence of malseating, with a third observer acting as a tiebreaker. Univariate analysis was conducted to determine risk factors for malseating with Youden’s index used to identify cut-off points. Cohen’s kappa test was used to measure interobserver and intraobserver reliability.Aims
Methods
This study investigates head-neck taper corrosion with varying head size in a novel hip simulator instrumented to measure corrosion related electrical activity under torsional loads. In all, six 28 mm and six 36 mm titanium stem-cobalt chrome head pairs with polyethylene sockets were tested in a novel instrumented hip simulator. Samples were tested using simulated gait data with incremental increasing loads to determine corrosion onset load and electrochemical activity. Half of each head size group were then cycled with simulated gait and the other half with gait compression only. Damage was measured by area and maximum linear wear depth.Aims
Methods
Hip resurfacing arthroplasty (HRA) is typically indicated for young and active patients. Due to the longevity of arthroplasty, these patients are likely to undergo revision surgery during their lifetime. There is a paucity of information on the long-term outcome of revision surgeries performed after failed HRA. The aim of our study was to provide survivorship data as well as clinical scores after HRA revisions. A total of 42 patients (43 hips) were revised after HRA at our centre to a variety of devices, including four HRA and 39 total hip arthroplasties (THAs). In addition to perioperative complications, University of California, Los Angeles (UCLA) hip scores and 12-Item Short-Form Health Survey questionnaire (SF-12) quality of life scores were collected at follow-up visits after the primary HRA and after revision surgery.Aims
Methods
In patients with a “dry” aspiration during the investigation of prosthetic joint infection (PJI), saline lavage is commonly used to obtain a sample for analysis. The aim of this study was to investigate prospectively the impact of saline lavage on synovial fluid analysis in revision arthroplasty. Patients undergoing revision hip (THA) or knee arthroplasty (TKA) for any septic or aseptic indication were enrolled. Intraoperatively, prior to arthrotomy, the maximum amount of fluid possible was aspirated to simulate a dry tap (pre-lavage) followed by the injection with 20 ml of normal saline and re-aspiration (post-lavage). Pre- and post-lavage synovial white blood cell (WBC) count, percent polymorphonuclear cells (%PMN), and cultures were compared.Aims
Methods
The diagnosis of periprosthetic joint infection (PJI) can be difficult. All current diagnostic tests have problems with accuracy and interpretation of results. Many new tests have been proposed, but there is no consensus on the place of many of these in the diagnostic pathway. Previous attempts to develop a definition of PJI have not been universally accepted and there remains no reference standard definition. This paper reports the outcome of a project developed by the European Bone and Joint Infection Society (EBJIS), and supported by the Musculoskeletal Infection Society (MSIS) and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Implant-Associated Infections (ESGIAI). It comprised a comprehensive review of the literature, open discussion with Society members and conference delegates, and an expert panel assessment of the results to produce the final guidance.Aims
Methods
Preoperative nasal All primary total hip arthroplasties (THA) and total knee arthroplasties (TKA) performed from January 2006 to April 2018 were retrospectively reviewed for the incidence of early PJI. Demographic parameters, risk factors for PJI (American Society of Anaesthesiologists classification, body mass index, smoking status, and diabetes mellitus) and implant types were collected. A preoperative screening and eradication protocol for nasal colonization of Aims
Methods
This study aimed to explore whether serum combined with synovial interleukin-6 (IL-6) measurement can improve the accuracy of prosthetic joint infection (PJI) diagnosis, and to establish the cut-off values of IL-6 in serum and synovial fluid in detecting chronic PJI. Patients scheduled to have a revision surgery for indications of chronic infection of knee and hip arthroplasties or aseptic loosening of an implant were prospectively screened before being enrolled into this study. The Musculoskeletal Infection Society (MSIS) definition of PJI was used for the classification of cases as aseptic or infected. Serum CRP, ESR, IL-6, and percentage of polymorphonuclear neutrophils (PMN%) and IL-6 in synovial fluid were analyzed. Statistical tests were performed to compare these biomarkers in the two groups, and receiver operating characteristic (ROC) curves and area under the curve (AUC) were analyzed for each biomarker.Aims
Methods
The rate of dislocation when traditional single bearing implants are used in revision total hip arthroplasty (THA) has been reported to be between 8% and 10%. The use of dual mobility bearings can reduce this risk to between 0.5% and 2%. Dual mobility bearings are more expensive, and it is not clear if the additional clinical benefits constitute value for money for the payers. We aimed to estimate the cost-effectiveness of dual mobility compared with single bearings for patients undergoing revision THA. We developed a Markov model to estimate the expected cost and benefits of dual mobility compared with single bearing implants in patients undergoing revision THA. The rates of revision and further revision were calculated from the National Joint Registry of England and Wales, while rates of transition from one health state to another were estimated from the literature, and the data were stratified by sex and age. Implant and healthcare costs were estimated from local procurement prices and national tariffs. Quality-adjusted life-years (QALYs) were calculated using published utility estimates for patients undergoing THA.Aims
Methods
Modular dual mobility (DM) prostheses in which a cobalt-chromium liner is inserted into a titanium acetabular shell ( This was a prospective study of patients between 18 and 65 years of age, with a body mass index (BMI) < 35 kg/m2 and University of California at Los Angeles (UCLA) activity score > 6, who received a modular cobalt-chromium acetabular liner, highly crosslinked polyethylene mobile bearing, and cementless titanium femoral stem for their primary THA. Patients with a history of renal disease and metal hardware elsewhere in the body were excluded. A total of 43 patients (30 male, 13 female; mean age 52.6 years (Aims
Patients and Methods
Dual mobility (DM) bearings are an attractive treatment option to obtain hip stability during challenging primary and revision total hip arthroplasty (THA) cases. The purpose of this study was to analyze data submitted to the American Joint Replacement Registry (AJRR) to characterize utilization trends of DM bearings in the USA. All primary and revision THA procedures reported to AJRR from 2012 to 2018 were analyzed. Patients of all ages were included and subdivided into DM and traditional bearing surface cohorts. Patient demographics, geographical region, hospital size, and teaching affiliation were assessed. Associations were determined by chi-squared analysis and logistic regression was performed to assess outcome variables.Aims
Methods
The aim of this study was to develop a novel computational model for estimating head/stem taper mechanics during different simulated assembly conditions. Finite element models of generic cobalt-chromium (CoCr) heads on a titanium stem taper were developed and driven using dynamic assembly loads collected from clinicians. To verify contact mechanics at the taper interface, comparisons of deformed microgroove characteristics (height and width of microgrooves) were made between model estimates with those measured from five retrieved implants. Additionally, these models were used to assess the role of assembly technique—one-hit versus three-hits—on the taper interlock mechanical behaviour.Aims
Methods
We have previously demonstrated raised cobalt and chromium levels in patients with larger diameter femoral heads, following metal-on-polyethylene uncemented total hip arthroplasty. Further data have been collected, to see whether these associations have altered with time and to determine the long-term implications for these patients and our practice. Patients from our previous study who underwent Trident-Accolade primary total hip arthroplasties using a metal-on-polyethylene bearing in 2009 were reviewed. Patients were invited to have their cobalt and chromium levels retested, and were provided an Oxford Hip Score. Serum ion levels were then compared between groups (28 mm, 36 mm, and 40 mm heads) and over time.Aims
Methods
This combined clinical and in vitro study aimed to determine the incidence of liner malseating in modular dual mobility (MDM) constructs in primary total hip arthroplasties (THAs) from a large volume arthroplasty centre, and determine whether malseating increases the potential for fretting and corrosion at the modular metal interface in malseated MDM constructs using a simulated corrosion chamber. For the clinical arm of the study, observers independently reviewed postoperative radiographs of 551 primary THAs using MDM constructs from a single manufacturer over a three-year period, to identify the incidence of MDM liner-shell malseating. Multivariable logistic regression analysis was performed to identify risk factors including age, sex, body mass index (BMI), cup design, cup size, and the MDM case volume of the surgeon. For the in vitro arm, six pristine MDM implants with cobalt-chrome liners were tested in a simulated corrosion chamber. Three were well-seated and three were malseated with 6° of canting. The liner-shell couples underwent cyclic loading of increasing magnitudes. Fretting current was measured throughout testing and the onset of fretting load was determined by analyzing the increase in average current.Aims
Methods
This study aimed to determine if macrophages can attach and directly affect the oxide layers of 316L stainless steel, titanium alloy (Ti6Al4V), and cobalt-chromium-molybdenum alloy (CoCrMo) by releasing components of these alloys. Murine peritoneal macrophages were cultured and placed on stainless steel, CoCrMo, and Ti6Al4V discs into a 96-well plate. Cells were activated with interferon gamma and lipopolysaccharide. Macrophages on stainless steel discs produced significantly more nitric oxide (NO) compared to their control counterparts after eight to ten days and remained elevated for the duration of the experiment.Aims
Methods
The aim of this study was to evaluate fretting and corrosion in retrieved oxidized zirconium (OxZr; OXINIUM, Smith & Nephew, Memphis, Tennessee) femoral heads and compare the results with those from a matched cohort of cobalt-chromium (CoCr) femoral heads. A total of 28 OxZr femoral heads were retrieved during revision total hip arthroplasty (THA) and matched to 28 retrieved CoCr heads according to patient demographics. The mean age at index was 56 years (46 to 83) in the OxZr group and 70 years (46 to 92) in the CoCr group. Fretting and corrosion scores of the female taper of the heads were measured according to the modified Goldberg scoring method.Aims
Patients and Methods
It is not known whether change in patient-reported outcome measures (PROMs) over time can be predicted by factors present at surgery, or early follow-up. The aim of this study was to identify factors associated with changes in PROM status between two-year evaluation and medium-term follow-up. Patients undergoing Birmingham Hip Resurfacing completed the Veteran’s Rand 36 (VR-36), modified Harris Hip Score (mHHS), Tegner Activity Score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at two years and a minimum of three years. A change in score was assessed against minimal clinically important difference (MCID) and patient-acceptable symptom state (PASS) thresholds. Binary logistic regression was used to assess the relationship between patient factors and deterioration in PASS status between follow-ups.Aims
Patients and Methods
The aim of this study was to evaluate blood metal ion levels, leucocyte profiles, and serum cytokines in patients with a total hip arthroplasty (THA) involving modular dual-mobility components. A total of 39 patients were recruited, with clinical follow-up of up to two years. Outcome was assessed using the Harris Hip Score (HHS, the 12-Item Short-Form Health Survey (SF-12), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and a visual analogue scale (VAS) for pain. Blood concentrations of cobalt (Co), chromium (Cr), and serum cytokines were measured. Subpopulations of leucocytes were analyzed by flow cytometry.Aims
Patients and Methods
To present a surgically relevant update of trunnionosis. Systematic review performed April 2017.Aims
Materials and Methods
Leucocyte esterase (LE) has been shown to be an accurate marker of prosthetic joint infection (PJI), and has been proposed as an alternative to frozen section (FS) histology for intraoperative diagnosis. In this study, the intraoperative assessment of LE was compared with FS histology for the diagnosis of prosthetic hip infection. A total of 119 patients undergoing revision total hip arthroplasty (THA) between June 2015 and December 2017 were included in the study. There were 56 men and 63 women with a mean age of 66.2 years (27 to 88). Synovial fluid was collected before arthrotomy for the assessment of LE using enzymatic colourimetric strips. Between five and six samples were stained with haematoxylin and eosin for FS histology, and considered suggestive of infection when at least five polymorphonuclear leucocytes were found in five high-power fields.Aims
Patients and Methods
This study presents the long-term survivorship, risk factors for prosthesis survival, and an assessment of the long-term effects of changes in surgical technique in a large series of patients treated by metal-on-metal (MoM) hip resurfacing arthroplasty (HRA). Between November 1996 and January 2012, 1074 patients (1321 hips) underwent HRA using the Conserve Plus Hip Resurfacing System. There were 787 men (73%) and 287 women (27%) with a mean age of 51 years (14 to 83). The underlying pathology was osteoarthritis (OA) in 1003 (75.9%), developmental dysplasia of the hip (DDH) in 136 (10.3%), avascular necrosis in 98 (7.4%), and other conditions, including inflammatory arthritis, in 84 (6.4%).Aims
Patients and Methods
Early evidence has emerged suggesting that ceramic-on-ceramic
articulations induce a different tissue reaction to ceramic-on-polyethylene
and metal-on-metal bearings. Therefore, the aim of this study was
to investigate the tissue reaction and cellular response to ceramic
total hip arthroplasty (THA) materials We investigated tissue collected at revision surgery from nine
ceramic-on-ceramic articulations. we compared our findings with
tissue obtained from five metal-on-metal THA revisions, four ceramic-on-polyethylene
THAs, and four primary osteoarthritis synovial membranes. The latter
were analyzed to assess the amount of tissue fibrosis that might
have been present at the time of implantation to enable evaluation,
in relation to implantation time, of any subsequent response in
the tissues.Aims
Patients and Methods
For this retrospective cohort study, patients aged ≤ 30 years
(very young) who underwent total hip arthroplasty (THA) were compared
with patients aged ≥ 60 years (elderly) to evaluate the rate of
revision arthroplasty, implant survival, the indications for revision,
the complications, and the patient-reported outcomes. We retrospectively reviewed all patients who underwent primary
THA between January 2000 and May 2015 from our institutional database.
A total of 145 very young and 1359 elderly patients were reviewed.
The mean follow-up was 5.3 years (1 to 18). Logistic generalized
estimating equations were used to compare characteristics and the revision
rate. Survival was evaluated using Kaplan–Meier curves and hazard
rates were created using Cox regression.Aims
Patients and Methods
The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI. We searched two literature databases, using terms that encompass all hip and knee arthroplasty procedures, as well as PJI and statistical terms reflecting diagnostic parameters. The findings are summarized as a narrative review.Objectives
Methods
Mechanical wear and corrosion at the head-stem junction of total hip arthroplasties (THAs) (trunnionosis) have been implicated in their early revision, most commonly in metal-on-metal (MOM) hips. We can isolate the role of the head-stem junction as the predominant source of metal release by investigating non-MOM hips; this can help to identify clinically significant volumes of material loss and corrosion from these surfaces. In this study we examined a series of 94 retrieved metal-on-polyethylene (MOP) hips for evidence of corrosion and material loss at the taper junction using a well published visual grading method and an established roundness-measuring machine protocol. Hips were retrieved from 74 male and 20 female patients with a median age of 57 years (30 to 76) and a median time to revision of 215 months (2 to 324). The reasons for revision were loosening of both the acetabular component and the stem (n = 29), loosening of the acetabular component (n = 58) and infection (n = 7). No adverse tissue reactions were reported by the revision surgeons.Objectives
Methods
Large ceramic femoral heads offer several advantages
that are potentially advantageous to patients undergoing both primary
and revision total hip replacement. Many high-quality studies have
demonstrated the benefit of large femoral heads in reducing post-operative instability.
Ceramic femoral heads may also offer an advantage in reducing polyethylene wear
that has been reported Cite this article: Bone Joint J 2013;95-B, Supple A:63–6.
The increased The proximal penetration of the femoral head five years post-operatively
was measured for 15 patients using radiostereometric analysis (RSA).Aims
Patients and Methods
The leading indication for revision total hip
arthroplasty (THA) remains aseptic loosening owing to wear. The younger,
more active patients currently undergoing THA present unprecedented
demands on the bearings. Ceramic-on-ceramic (CoC) bearings have
consistently shown the lowest rates of wear. The recent advances,
especially involving alumina/zirconia composite ceramic, have led
to substantial improvements and good results Alumina/zirconia composite ceramics are extremely hard, scratch
resistant and biocompatible. They offer a low co-efficient of friction
and superior lubrication and lower rates of wear compared with other
bearings. The major disadvantage is the risk of fracture of the
ceramic. The new composite ceramic has reduced the risk of fracture
of the femoral head to 0.002%. The risk of fracture of the liner
is slightly higher (0.02%). Assuming that the components are introduced without impingement,
CoC bearings have major advantages over other bearings. Owing to
the superior hardness, they produce less third body wear and are
less vulnerable to intra-operative damage. The improved tribology means that CoC bearings are an excellent
choice for young, active patients requiring THA. Cite this article:
Hip resurfacing arthroplasty (HRA) is an alternative to conventional
total hip arthroplasty for patients with osteonecrosis (ON) of the
femoral head. Our aim was to report the long-term outcome of HRA,
which is not currently known. Long-term survivorship, clinical scores and radiographic results
for 82 patients (99 hips) treated with HRA for ON over a period
of 18 years were reviewed retrospectively. The mean age of the 67
men and 15 women at the time of surgery was 40.8 years (14 to 64).
Patients were resurfaced regardless of the size of the osteonecrotic
lesion.Aims
Patients and Methods
Modular junctions are ubiquitous in contemporary hip arthroplasty. The head-trunnion junction is implicated in the failure of large diameter metal-on-metal (MoM) hips which are the currently the topic of one the largest legal actions in the history of orthopaedics (estimated costs are stated to exceed $4 billion). Several factors are known to influence the strength of these press-fit modular connections. However, the influence of different head sizes has not previously been investigated. The aim of the study was to establish whether the choice of head size influences the initial strength of the trunnion-head connection. Ti-6Al-4V trunnions (n = 60) and two different sizes of cobalt-chromium (Co-Cr) heads (28 mm and 36 mm; 30 of each size) were used in the study. Three different levels of assembly force were considered: 4 kN; 5 kN; and 6 kN (n = 10 each). The strength of the press-fit connection was subsequently evaluated by measuring the pull-off force required to break the connection. The statistical differences in pull-off force were examined using a Kruskal–Wallis test and two-sample Mann–Whitney U test. Finite element and analytical models were developed to understand the reasons for the experimentally observed differences.Objectives
Materials and Methods
Tribocorrosion at the head–neck taper interface
– so-called ‘taperosis’ – may be a source of metal ions and particulate
debris in metal-on-polyethylene total hip arthroplasty (THA). We examined the effect of femoral head length on fretting and
corrosion in retrieved head–neck tapers Head length was observed to affect fretting (p = 0.03), with
28 mm + 8 mm femoral heads showing greater total fretting scores
than all other head lengths. The central zone of the femoral head
bore taper was subject to increased fretting damage (p = 0.01),
regardless of head length or stem offset. High-offset femoral stems
were associated with greater total fretting of the bore taper (p
= 0.04). Increased fretting damage is seen with longer head lengths and
high-offset femoral stems, and occurs within a central concentric
zone of the femoral head bore taper. Further investigation is required
to determine the effect of increased head size, and variations in
head–neck taper design. Cite this article:
The August 2014 Hip &
Pelvis Roundup360 looks at: Serial MRIs best for pseudotumour surveillance; Is ultrasound good enough for MOM follow-up?; Does weight loss in obese patients help?; Measuring acetabular anteversion on plain films; Two-stage one-stage too many in fungal hip revisions? and 35 is the magic number in arthroplasty.
The October 2014 Hip &
Pelvis Roundup360 looks at: functional acetabular orientation; predicting re-admission following THR; metal ions and resurfacing; lipped liners increase stability; all anaesthetics equal in hip fracture surgery; revision hip surgery in very young patients; and uncemented hips.
A modular femoral head–neck junction has practical
advantages in total hip replacement. Taper fretting and corrosion
have so far been an infrequent cause of revision. The role of design
and manufacturing variables continues to be debated. Over the past
decade several changes in technology and clinical practice might
result in an increase in clinically significant taper fretting and
corrosion. Those factors include an increased usage of large diameter
(36 mm) heads, reduced femoral neck and taper dimensions, greater
variability in taper assembly with smaller incision surgery, and
higher taper stresses due to increased patient weight and/or physical
activity. Additional studies are needed to determine the role of
taper assembly compared with design, manufacturing and other implant
variables. Cite this article:
The August 2013 Hip &
Pelvis Roundup360 looks at: are we getting it right first time?; tantalum augments in revision hip surgery; lower wear in dual mobility?; changing faces changes outcomes; synovial fluid aspiration in MOM hips; taper disease: the new epidemic of hip surgery; the super-obese and THR; and whether well fixed stems can remain in infected hips
In this prospective study a total of 80 consecutive
Chinese patients with Crowe type I or II developmental dysplasia of
the hip were randomly assigned for hip resurfacing arthroplasty
(HRA) or total hip replacement (THR). Three patients assigned to HRA were converted to THR, and three
HRA patients and two THR patients were lost to follow-up. This left
a total of 34 patients (37 hips) who underwent HRA and 38 (39 hips)
who underwent THR. The mean follow-up was 59.4 months (52 to 70)
in the HRA group and 60.6 months (50 to 72) in the THR group. There was
no failure of the prosthesis in either group. Flexion of the hip
was significantly better after HRA, but there was no difference
in the mean post-operative Harris hip scores between the groups.
The mean size of the acetabular component in the HRA group was significantly
larger than in the THR group (49.5 mm vs 46.1 mm, p = 0.001). There was
no difference in the mean abduction angle of the acetabular component
between the two groups. Although the patients in this series had risk factors for failure
after HRA, such as low body weight, small femoral heads and dysplasia,
the clinical results of resurfacing in those with Crowe type I or
II hip dysplasia were satisfactory. Patients in the HRA group had
a better range of movement, although neck-cup impingement was observed.
However, more acetabular bone was sacrificed in HRA patients, and
it is unclear whether this will have an adverse effect in the long
term.
Early failure associated with adverse reactions to metal debris is an emerging problem after hip resurfacing but the exact mechanism is unclear. We analysed our entire series of 660 metal-on-metal resurfacings (Articular Surface Replacement (ASR) and Birmingham Hip Resurfacing (BHR)) and large-bearing ASR total hip replacements, to establish associations with metal debris-related failures. Clinical and radiological outcomes, metal ion levels, explant studies and lymphocyte transformation tests were performed. A total of 17 patients (3.4%) were identified (all ASR bearings) with adverse reactions to metal debris, for which revision was required. This group had significantly smaller components, significantly higher acetabular component anteversion, and significantly higher whole concentrations of blood and joint chromium and cobalt ions than asymptomatic patients did (all p <
0.001). Post-revision lymphocyte transformation tests on this group showed no reactivity to chromium or cobalt ions. Explants from these revisions had greater surface wear than retrievals for uncomplicated fractures. The absence of adverse reactions to metal debris in patients with well-positioned implants usually implies high component wear. Surgeons must consider implant design, expected component size and acetabular component positioning in order to reduce early failures when performing large-bearing metal-on-metal hip resurfacing and replacement.