Exeter V40 Stem Research Articles

Equivalent revision rates and patient reported outcomes with routine use of a short (125mm) cemented stem for total hip arthroplasty compared to a standard length (150mm) cemented stem. A two surgeon series of 1335 patients.

Routine total hip arthroplasty (THA) using a short cemented stem as compared with a standard length cemented stem may have benefits in terms of stress distribution, bone preservation, stem subsidence and ease of revision surgery. Two senior arthroplasty surgeons transitioned their routine femoral implant from a standard 150mm Exeter V40 cemented stem to a short 125mm Exeter V40 cemented stem for all patients over the course of several years. We analysed revision rates, adjusted survival, and PROMS scores for patients who received a standard stem and a short stem in routine THA. All THAs performed by the two surgeons between January 2011 and December 2021 were included. All procedures were performed using either a 150mm or 125mm Exeter V40 stem. Demographic data, acetabular implant type, and outcome data including implant survival, reason for revision, and post-operative Oxford Hip Scores were obtained from the New Zealand Joint Registry (NZJR), and detailed survival analyses were performed. Primary outcome was revision for any reason. Reason for revision, including femoral or acetabular failure, and time to revision were also recorded. 1335 THAs were included. 516 using the 150mm stem and 819 using the 125mm stem. There were 4055.5 and 3227.8 component years analysed in the standard stem and short stem groups respectively due to a longer mean follow up in the 150mm group. Patient reported outcomes were comparable across all groups. Revision rates were comparable between the standard 150mm stem (0.44 revisions/100 component years) and the short 125mm stem (0.56 revisions/100 component years) with no statistically significant difference found (p = 0.240). Routine use of a short 125mm stem had no statistically significant impact on revision rate or PROMS scores when compared to a standard 150mm stem. There may be benefits to routine use of a short cemented femoral implant.

CAN ARTHOPLASTY STEM INFLUENCE OUTCOME (CASINO): A RANDOMIZED CONTROLLED TRIAL OF STEM LENGTH IN CEMENTED TOTAL HIP ARTHROPLASTY

In this RCT the primary aim was to assess whether a short (125mm) Exeter V40 stem offered an equivalent hip specific function compared to the standard (150mm) stem when used for cemented total hip arthroplasty (THA). Secondary aims were to evaluate health-related quality of life (HRQoL), patient satisfaction, stem height and alignment, radiographic loosening, and complications between the two stems.A prospective multicentre double-blind randomised control trial was conducted. During a 15-month period, 220 patients undergoing THA were randomised to either a standard (n=110) or short (n=110) stem Exeter. There were no significant (p≥0.065) differences in preoperative variables between the groups. Functional outcomes and radiographic assessment were undertaken at 1- and 2-years.There were no differences (p=0.428) in hip specific function according to the Oxford hip score at 1-year (primary endpoint) or at 2-years (p=0.767) between the groups. The short stem group had greater varus angulation (0.9 degrees, p=0.003) when compared to the standard group and were more likely (odds ratio 2.42, p=0.002) to have varus stem alignment beyond one standard deviation from the mean. There were no significant (p≥0.083) differences in the Forgotten joint scores, EuroQol-5-Dimension, EuroQol-VAS, Short form 12, patient satisfaction, complications, stem height or radiolucent zones at 1 or 2-years between the groups.The Exeter short stem offers equivalent hip specific function, HRQoL, patient satisfaction, and limb length when compared to the standard stem at 2-years post-operation. However, the short stem was associated with a greater rate of varus malalignment which may influence future implant survival.

Mixed manufacturer dual mobility bearing and the Exeter V40 Stem: is it safe? Short-term results in primary and revision hip replacement.

The aim is to review clinical and radiological outcomes for all cases of primary and revision THA, combining a cemented stem (Exeter V40) with a dual mobility component from a different manufacturer (SERF Novae), to evaluate whether concerns regarding mixing components from different manufacturers are justified. We identified 72 hip replacements performed between May 2010 and December 2015 using the SERF Novae dual mobility cup with an Exeter V40 stem, the majority of which were cemented (90%) and revisions (58%). Patients were evaluated clinically and radiologically at a minimum of two years. There were five (6.9%) dislocations; three (4.2%) requiring revision - one of which was an intra-prosthetic disarticulation and two infections. No cases were lost to follow-up and 49 surviving cases were reviewed at a mean of 4.0 (range 1.8-8.1) years following surgery. Pain and functional outcome scores all improved. There were no radiological failures and no revisions for aseptic loosening of stem or cup. The combination of Exeter cemented stem with a dual mobility bearing from a different manufacturer results in acceptable short-term outcomes in terms of hip stability, revision rates and patient-reported measures.

Survival of the Exeter V40 short revision (44/00/125) stem when used in primary total hip arthroplasty

The Exeter V40 femoral stem is the most implanted stem in the National Joint Registry (NJR) for primary total hip arthroplasty (THA). In 2004, the 44/00/125 stem was released for use in 'cement-in-cement' revision cases. It has, however, been used 'off-label' as a primary stem when patient anatomy requires a smaller stem with a 44 mm offset. We aimed to investigate survival of this implant in comparison to others in the range when used in primary THAs recorded in the NJR. We analyzed 328,737 primary THAs using the Exeter V40 stem, comprising 34.3% of the 958,869 from the start of the NJR to December 2018. Our exposure was the stem, and the outcome was all-cause construct revision. We stratified analyses into four groups: constructs using the 44/00/125 stem, those using the 44/0/150 stem, those including a 35.5/125 stem, and constructs using any other Exeter V40 stem. In all 328,737 THAs using an Exeter V40 stem, the revision estimate was 2.8% (95% confidence interval (CI) 2.7 to 2.8). The 44/00/125 stem was implanted in 2,158 primary THAs, and the ten-year revision estimate was 4.9% (95% CI 3.6 to 6.8). Controlling for age, sex, year of operation, indication, and American Society of Anesthesiologists grade demonstrated an increased overall hazard of revision for constructs using the 44/00/125 stem compared to constructs using other Exeter V40 femoral stems (hazard ratio 1.8 (95% CI 1.4 to 2.3)). Although the revision estimate is within the National Institute for Health and Care Excellence ten-year benchmark, survivorship of constructs using the 44/00/125 stem appears to be lower than the rest of the range. Adjusted analyses will not take into account 'confounding by indication', e.g. patients with complex anatomy who may have a higher risk of revision. Surgeons and patients should be reassured but be aware of the observed increased revision estimate, and only use this stem when other implants are not suitable.

Does the Nottingham Hip Fracture Score Help Predict Which Patients Will Benefit From a Modern Modular Hemiarthroplasty for the Treatment of Intracapsular Proximal Femoral Fractures?

Introduction: Hemiarthroplasty for the management of intracapsular neck of femur fractures is common but current practice in the UK still varies regionally and individually. Guided by the National Institute of Health and Care Excellence (NICE) we have observed a move towards modern, modular prostheses such as the Exeter V40 Stem but the use of older, monoblock prostheses such as the Thompsons Hemiarthroplasty remains controversial. Use of the Nottingham Hip Fracture Scores (NHFS) can help surgeons stratify patients according to risk and select the most appropriate prosthesis to meet their individual needs. Materials and Methods: 765 hip hemiarthroplasties were analysed over a 28-month period at a single, high-volume, orthopaedic department in the UK. We calculated the NHFS and recorded the choice of prosthesis. Patients were then followed up for at least a year. Outcomes were mortality and change in residential status. Results: Six hundred and forty-six (446) patients were treated with monoblock prostheses (mean age=85.6; range 62-105). 319 patients received modular prostheses (mean age=81.0; range 61-98). Patients who were selected to receive a monoblock prosthesis were over twice as likely to be dead at a year (32.87% vs. 13.65%) and over twice as likely to require increased assistance with living (50.12% vs. 23.81%). Amongst patients with equivocal NHFS, those who receive a monoblock stem suffered worse outcomes in all but the very highest risk group, who experienced lower mortality (OR=0.71, CI 0.52-0.96) and change in residential status (OR=0.76, CI 0.58-0.99). Conclusion: Nottingham Hip Fracture Score (NHFS) can confer predictable outcomes in hip fracture patients treated with modular stems. Modular stems should be the default choice when performing hemiarthroplasties for intracapsular neck of femur fractures. However, in keeping with other studies, we found that in very old, frail, or co-morbid patients, modular stems are not associated with better survival or return to pre-morbid function.

Analysis of the Exeter V40 femoral stem prosthesis fracture : systematic review and single centre case series.

AimsThe Exeter V40 cemented polished tapered stem system has demonstrated excellent long-term outcomes. This paper presents a systematic review of the existing literature and reports on a large case series comparing implant fractures between the Exeter V40 series; 125 mm and conventional length stem systems.MethodsA systematic literature search was performed adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. In parallel, we performed a retrospective single centre study of Exeter V40 femoral stem prosthetic fractures between April 2003 and June 2020.ResultsThere are 25 reported cases of such prosthetic fractures confined to small case series and case reports within the literature. We report an additional 19 cases to the literature (mean age 66.3 years (SD 11.7); 12 (63%) females; BMI 32.9 kg/m2 (SD 5.9)). The mean time from index procedure to fracture was 7.8 years (SD 3.6; 2.5 to 16.3). Exeter V40 stem fracture incidence was 0.15% and 1.21% for primary and revision arthroplasty, respectively. Incidence was significantly higher in revision arthroplasty (p < 0.001) and 125 mm length stems compared to ≥ 150 mm length stems (1.25% vs 0.13%, respectively; p < 0.001). When comparing different stem length cohorts, 125 mm short-stems were associated with stem-body fractures (92% vs 29%; p = 0.0095), earlier time to fracture (6.2 years vs 11.0 years; p = 0.0018), younger patient age at time of fracture (62.7 years vs 72.6 years; p = 0.037), and female sex (75% vs 43%; p = 0.326).ConclusionThis complication remains rare, although we report a significantly higher incidence at up to 17 years follow-up than in the literature. Short 125 mm length Exeter V40 stems undoubtedly have a role in restoring anatomy and biomechanics in smaller femoral geometries, although the surgeon has to appreciate the higher risk of stem fracture and the associated predisposing factors which may necessitate particular attention to surgical technique and planning.Cite this article: Bone Jt Open 2021;2(6):443–456.

324 Outcomes of the Exeter V40 Cemented Femoral Stem at a Minimum of 10 Years in a Non-designer Centre

Abstract Introduction The Exeter V40 cemented femoral stem was first introduced in 2000. The largest single-centre analysis of this implant to date was published in 2018, with excellent results at a minimum of 10-years for the first 540 cases performed at the designer centre in the Exeter NHS Trust. The aim of this current study is to report long term outcomes and survivorship for the Exeter V40 stem in a non-designer centre. Method All patients undergoing primary total hip arthroplasty using the Exeter V40 femoral stem between January 1st 2005 and January 31st 2010 were eligible for inclusion. Outcome measures included data on all components in situ beyond 10 years, death occurring within 10 years with components in situ and all-cause revision surgery. Results A total of 829 stems were included in the data set. Of these, 808 (97.5%) had no further surgery within the follow-up period; 648 stems (78.1%) were in situ beyond 10 years, and 165 (19.9%) were in situ at death before 10 years. The mean preoperative WOMAC score was 61±15.9 with a mean postoperative score of 20.4±19.3. Conclusions The Exeter V40 cemented femoral stem demonstrates excellent functional outcomes and survival when used in a high-volume non-designer centre.

The influence of migration of the exeter V40 stem on patient reported outcome measures: a 2-year follow-up of 112 total hip arthroplasties using radiostereometric analysis

The cemented Exeter V40 stem is known to migrate distally. Several previous studies have reported on the extent of stem migration and its influence on clinical outcome. However, no studies have investigated the influence of stem migration on Patient Reported Outcome Measures (PROM). One hundred and twelve total hip arthroplasties (THA) were included in a 2-year follow-up using Radiostereometric Analysis (RSA). Patients were evaluated using the Oxford Hip Score (OHS) and EQ-5D-3L PROMs. The purpose of this study was to assess the influence of stem migration, measured by Maximum Total Point Motion (MTPM), on the 2-year postoperative score (OHS and EQ-5D). Furthermore, the influence of pre-operative PROM, age, gender, acetabular component and BMI was associated with the 2-year postoperative OHS and EQ-5D scores. MTPM was a non-significant predictor of the 2-year postoperative OHS (regression coefficient (B) = − 2.38 (CI − 5.44; .69)) and of the 2-year postoperative EQ-5D (B = − .01 (CI − .04; .02)). The only significant predictor of the 2-year postoperative OHS and 2-year postoperative EQ-5D was gender (B = 8.71 (CI 3.52; 13.90)) and (B = .13 (CI .07; .18)), respectively. Stem migration did not significantly influence PROMs at 2 years post-operatively. Using a patient-focused approach, our results seem to corroborate results reported by previous studies, showing that slow migration of the Exeter V40 stem does not seem to influence the clinical outcome.

Outcomes of the Exeter V40 cemented femoral stem at a minimum of ten years in a non-designer centre.

AimsThe Exeter V40 cemented femoral stem was first introduced in 2000. The largest single-centre analysis of this implant to date was published in 2018 by Westerman et al. Excellent results were reported at a minimum of ten years for the first 540 cases performed at the designer centre in the Exeter NHS Trust, with stem survivorship of 96.8%. The aim of this current study is to report long-term outcomes and survivorship for the Exeter V40 stem in a non-designer centre.MethodsAll patients undergoing primary total hip arthroplasty using the Exeter V40 femoral stem between 1 January 2005 and 31 January 2010 were eligible for inclusion. Data were collected prospectively, with routine follow-up at six to 12 months, two years, five years, and ten years. Functional outcomes were assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. Outcome measures included data on all components in situ beyond ten years, death occurring within ten years with components in situ, and all-cause revision surgery.ResultsA total of 829 stems in 745 patients were included in the dataset; 155 patients (20.8%) died within ten years, and of the remaining 664 stems, 648 stems (97.6%) remained in situ beyond ten years. For the 21 patients (2.5%) undergoing revision surgery, 16 femoral stems (1.9%) were revised and 18 acetabular components (2.2%) were revised. Indications for revision in order of decreasing frequency were infection (n = 6), pain (n = 6), aseptic component loosening (n = 3), periprosthetic fracture (n = 3), recurrent dislocation (n = 2), and noise production (ceramic-on-ceramic squeak) (n = 1). One patient was revised for aseptic stem loosening. The mean preoperative WOMAC score was 61 (SD 15.9) with a mean postoperative score of 20.4 (SD 19.3) (n = 732; 88.3%).ConclusionThe Exeter V40 cemented femoral stem demonstrates excellent functional outcomes and survival when used in a high volume non-designer centre. Outcomes are comparable to those of its serially validated predecessor, the Exeter Universal stem.Cite this article: Bone Jt Open 2020;1-12:743–748.

AB126. Outcomes of the Exeter v40 cemented femoral stem at a minimum of 10 years follow-up in a non-designer centre

Background: The Stryker Exeter V40 cemented femoral stem was first introduced in 2000. The largest analysis of this implant conducted so far was published in 2018 by Westermann et al. with a minimum 10-year follow-up of the first 540 cases performed in the designer centre in the Exeter NHS Trust, and demonstrated excellent long term survival. The aim of this study is to report long term outcomes and survivorship for the Exeter V40 stem from a non-designer centre.

A Novel Technique for Exeter Stem Extraction

We describe a new technique for extraction of the Exeter V40 stem using the readily available Exeter offset broach handle.

Can Arthroplasty Stem INfluence Outcome? (CASINO): a randomized controlled equivalence trial of 125\xa0mm versus 150\xa0mm Exeter V40 stems in total hip arthroplasty

BackgroundThe use of shorter length femoral stems during total hip arthroplasty has been suggested to accommodate wider patient femoral geometry and offer maximal bone preservation. However, cemented short-stem designs may increase the risk of varus stem malalignment and influence patient outcomes.Methods/DesignCASINO is a multi-centre randomised equivalence trial that will recruit 220 patients undergoing total hip arthroplasty for osteoarthritis at two NHS hospitals in Scotland. Patients will be aged 45–80, undergoing unilateral primary hip arthroplasty, with no plan for contralateral procedure within the study timeframe, and able to comply with the protocol. Participants will be randomised to receive either a short (125 mm) or a standard (150 mm) Exeter V40 stem. The Contemporary acetabular component will be used in all cases. All implants will be cemented.Patient pain, function and satisfaction will be assessed using change from baseline measurement in Oxford Hip Score, Forgotten Joint Score, EQ-5D, pain numerical rating scores, and patient satisfaction questionnaire at baseline and at 1 and 2 years following surgery. Radiographic assessment will evaluate stem position and will be appraised by independent reviewers. Patients will be blind to implant allocation.DiscussionStem length may be associated with outcome; however, we can find no randomised trial in which researchers investigated the effect of stem length on patient outcome following cemented total hip arthroplasty. The aim of this trial is to determine if the use of short cemented stems offers equivalent patient outcomes to those achieved following surgery with standard length stems.Trial registrationInternational Standard Randomised Controlled Trial Number, ISRCTN13154542, Registered on 30 June 2017.

Neck fracture of the Exeter stem in 3 patients

A 63-year-old woman (height 1.70 m, weight 92 kg, BMI 31) with developmental dysplasia of both hips underwent bilateral hybrid total hip replacement (THR) using the cemented Exeter V40 stem (offset...

Determining material loss from the femoral stem trunnion in hip arthroplasty using a coordinate measuring machine.

In contrast to the articulating and taper surfaces of failed total hip replacements, volumetric wear analysis of trunnions is not routinely performed. Metal wear particles from the trunnion may contribute not only to the failures of metal-on-metal total hip replacements but also to all hip replacements utilising metal trunnions. A validation study was performed with the material removed in stages from the trunnions of an Exeter V40 stem, a Corail stem and an Accolade stem to simulate different magnitudes of wear. The material loss from the trunnions was measured both volumetrically with a coordinate measuring machine and gravimetrically with a high-precision balance. A cohort of 28 ex vivo trunnions was also measured using the coordinate measuring machine. The maximum error between the two methods was found to be 0.13 mm(3). This result was comparable with the coordinate measuring machine method for the taper surface (0.2 mm(3)). The ex vivo trunnions had a median wear volume of 0.14mm(3) (range: 0.04-0.28 mm(3)). This is the first study to determine the accuracy of volumetric wear measurements of trunnions by comparing against gravimetric measurements. Volumetric wear analysis of trunnions may provide additional insights into failures of modular total hip prostheses and will be performed routinely at our centre.

Metal Ion Levels Post Primary Unilateral Exeter Total Hip Arthroplasty

Metal ion release is common following total hip arthroplasty, yet postoperative levels have not been defined for most stems currently used in clinical practice. To assess metal ion release in the serum of patients with well functioning unilateral Exeter V40 primary total hip arthroplasties one year after surgery. Whole blood chromium and serum cobalt levels were measured in 20 patients following primary total hip arthroplasty with the Exeter V40 stem and a variety of acetabular components one year after surgery. Whole blood chromium levels were within the normal range (10-100 nmol/L), with a single mild elevation of serum cobalt (normal <20 nmol/L). In well functioning primary unilateral total hip arthroplasty using the Exeter V40 stem with a variety of acetabular components one year post surgery, whole blood chromium levels are normal and serum cobalt elevations are rare and mild.

Biomechanical Evaluation for Mechanisms of Periprosthetic Femoral Fractures

There are a number of biomechanical tests for various treatment options of periprosthetic femoral fractures, but different loading modalities prelude their direct comparison. This study was designed to develop an experimental model of osteoporotic bone fractures near the femoral stem that is based on a simple testing protocol to increase the reproducibility. In addition, we wanted to clarify whether a femoral prosthetic stem reduces the femoral fracture strength. Twenty human cadaveric femurs were harvested, and five groups were randomized on the basis of the bone mineral density using a pQCT device. The specimens of three groups were provided with a cemented Exeter V40 stem and loaded to failure with torsion (I), anterior (II), and lateral load (III). The femurs of groups IV and V remained uninstrumented and were tested in a four-point bending assay similar to groups II and III. All biomechanical testings were realized with a servohydraulic testing machine (MTS). There was no significant difference regarding bone mineral density of all groups. Torsional testing generated proximal intertrochanteric fractures and anterior loading resulted exclusively in supracondylar fractures. Introducing the force from the lateral side, all fracture lines occurred close to the tip of the stem, similar to a Vancouver-B fracture. Assuming that lateral load application is a main responsible mechanism of periprosthetic femoral fracture near the tip of the stem, the fracture strength of instrumented femurs was significantly reduced (group III: 4,692 N vs. group V: 6,931 N; p < 0.05). Prosthetic stems reduce femoral fracture strength significantly. In an osteoporotic bone model, a four-point bending test with lateral load application seems to be a suitable approach.