Choice of implant combinations in total hip replacement: systematic review and network meta-analysis

Functional assessment in patients undergoing total hip arthroplasty

Aims

Conventional patient-reported surveys, used for patients undergoing total hip arthroplasty (THA), are limited by subjectivity and recall bias. Objective functional evaluation, such as gait analysis, to delineate a patient's functional capacity and customize surgical interventions, may address these shortcomings. This systematic review endeavours to investigate the application of objective functional assessments in appraising individuals undergoing THA.

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were applied. Eligible studies of THA patients that conducted at least one type of objective functional assessment both pre- and postoperatively were identified through Embase, Medline/PubMed, and Cochrane Central database-searching from inception to 15 September 2023. The assessments included were subgrouped for analysis: gait analysis, motion analysis, wearables, and strength tests.

Results

A total of 130 studies using 15 distinct objective functional assessment methods (FAMs) were identified. The most frequently used method was instrumented gait/motion analysis, followed by the Timed-Up-and-Go test (TUG), 6 minute walk test, timed stair climbing test, and various strength tests. These assessments were characterized by their diagnostic precision and applicability to daily activities. Wearables were frequently used, offering cost-effectiveness and remote monitoring benefits. However, their accuracy and potential discomfort for patients must be considered.

Conclusion

The integration of objective functional assessments in THA presents promise as a progress-tracking modality for improving patient outcomes. Gait analysis and the TUG, along with advancing wearable sensor technology, have the potential to enhance patient care, surgical planning, and rehabilitation.

The utility of cemented femoral stems in modern THA: a 10-year comparative analysis of the Charnley and Exeter stems

BACKGROUND

Total hip replacement (THR) is one of the most common surgical procedures performed worldwide. The controversy surrounding the relative merits of a cemented composite beam or cemented taper-slip stem in total hip replacement continues. Our aims primarily were to assess the 10-year outcomes of cemented stems using Charnley and Exeter prostheses with regional registry data and secondarily to assess the main predictors of revision.

METHODS

We prospectively collected registry data for procedures performed between January 2005 and June 2008. Only cemented Charnley and Exeter stems were included. Patients were prospectively reviewed at 6 months, 2, 5 and 10 years. The primary outcome measure was a 10-year all-cause revision. Secondary outcomes included 're-revision', 'mortality' and functional 'Western Ontario and McMaster Universities Osteoarthritis Index' (WOMAC) scores.

RESULTS

We recorded a total of 1351 cases in the cohort, 395 Exeter and 956 Charnley stems. The overall all-cause revision rate at 10 years was 1.6%. The revision rate for Charnley stem was 1.4% and 2.3% revision rate for all Exeter stems with no significant difference noted between the two cohorts (p = 0.24). The overall time to revision was 38.3 months. WOMAC scores at 10 years were found to be insignificantly higher for Charnley stems (mean 23.8, σ = 20.11) compared to Exeter stems (mean 19.78, σ = 20.72) (p = 0.1).

CONCLUSION

There is no significant difference between cemented Charnley and Exeter stems; they both perform well above the international average. The decline in the use of cemented THA is not fully supported by this regional registry data.

Experience of an Anatomic Femoral Stem in a United Kingdom Center - Excellent Survivorship and Negligible Periprosthetic Fracture Rates at Mean 12 Years Following Primary Total Hip Arthroplasty

BACKGROUND

As the clinical burden of periprosthetic fractures (PPFs) continues to increase, it has been suggested that the use of anatomical femoral stems may help reduce PPF risk. The primary aim of this study was to determine the survivorship and PPF rate of an anatomical femoral stem in a single center at minimum 10-year follow-up.

METHODS

A total of 1,000 consecutive total hip arthroplasties (THAs) performed using an anatomical femoral stem were identified from a prospectively collected arthroplasty database. Patient radiographs were reviewed finally at a mean of 12 years (range, 10 to 16 years) following surgery to identify any revision surgery, dislocations or PPFs. Mean patient age at surgery was 69 years (range, 24 to 93). There were 634 women (63%). Osteoarthritis was the operative indication in 946 patients (95%).

RESULTS

All-cause THA survivorship was 99.1% (95% confidence interval (CI), 99.0-99.3%) at 10 years and 97.9% (CI, 97.8 - 98.0%) at 15 years. Stem survivorship at 10 years was 99.6% (CI, 99.5-99.7%) and at 15 years was 98.2% (CI, 98.1-98.3%). The 15-year stem survival for aseptic loosening was 100% with no cases of significant lysis found (lucent line >2mm). Implant survivorship was not significantly impacted by patient sex (P = .65), body mass index (P = .49), deprivation level (P = .284), operative indication (P = .33), or American Society of Anesthesiologists class (P = .374). There were 3 PPFs identified (0.3%) at mean 12-year follow-up and 15 dislocations (1.5%).

CONCLUSION

This anatomical femoral stem demonstrated excellent survivorship and negligible PPF rates at mean 12-year follow-up following primary THA.

Head, acetabular liner composition, and rate of revision and wear in total hip arthroplasty: a Bayesian network meta-analysis

Total hip arthroplasty (THA) is a common procedure for patients suffering from hip pain e.g. from osteoarthritis, osteonecrosis, or hip fractures. The satisfaction of patients undergoing THA is influenced by the choice of implant type and material, with one key factor being the selection of the appropriate material combination for the bearing surface. In this Bayesian network meta-analysis, we investigated the impact of material combinations for the bearing surface on the longevity of hip implants. The wear penetration rate per year and the total wear penetration in the liner resulting from different material combinations, as well as the survival rate at last follow-up, were examined. We analyzed a total of 663,038 THAs, with 55% of patients being women. Mean patient age was 59.0 ± 8.1 years and mean BMI 27.6 ± 2.6 kg/m2. The combination of an aluminium oxide (Al2O3) head and an Al2O3 liner demonstrated the lowest wear penetration at last follow-up and the lowest rate of wear penetration per year. Additionally, the combination of a crosslinked polyethylene (XLPE) liner and a zircon oxide (ZrO2) head demonstrated the lowest rate of revision at last follow-up. These findings underscore the importance of careful material selection for hip implant bearing surfaces to optimize their longevity and patient satisfaction after THA.

Prolonged release of an antimicrobial peptide GL13K-loaded thermosensitive hydrogel on a titanium surface improves its antibacterial and anti-inflammatory properties

The application of titanium in the orthopedic and dental fields is associated with bacterial infection and chronic inflammation, especially in the early stages after its implantation. In the present study, we investigated the antibacterial and anti-inflammatory activities of a titanium surface that was immobilized in a thermosensitive PLGA-PEG-PLGA hydrogel containing the antimicrobial peptide GL13K. The FTIR results confirmed the successful loading of GL13K. The degradation of the hydrogel and release of GL13K persisted for two weeks. The modified titanium surface exhibited a significant inhibitory effect on Porphyromonas gingivalis in contact with its surface, as well as an inhibitory effect on P.g in the surrounding environment by releasing GL13K antimicrobial peptides. The modified titanium surfaces were biocompatible with RAW264.7. Furthermore, the expression of pro-inflammatory cytokines IL-1β, TNF-α and iNOS was down-regulated, whereas anti-inflammatory cytokines Arg-1, IL-10 and VEGF-A were up-regulated on the modified titanium surfaces on days 3 and 5. This effect was attributed to the polarization of macrophages from the M1 to M2 phenotype, which was confirmed by the detection of macrophage M1/M2 biomarkers via immunofluorescence staining and flow cytometry. Thus, the thermosensitive PLGA-PEG-PLGA hydrogel release system carrying the antimicrobial peptide GL13K on a titanium surface exhibited antibacterial and anti-inflammatory properties and promoted macrophage polarization from the M1 to M2 phenotype, which may help create a favourable niche for bone formation under infective condition.

Comparisons of Different Bearing Surfaces in Cementless Total Hip Arthroplasty: A Systematic Review and Bayesian Network Analysis

BACKGROUND

We aimed to make comparisons of different bearing surfaces in patients after cementless total hip arthroplasty.

METHODS

The network meta-analysis was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. The primary outcomes were implant survival and Harris hip score (HHS). Secondary outcomes included linear wear rates and serum level of metal ions. Subgroup analyses were performed by: (1) classifying head sizes as small and large; (2) femoral heads as ceramic and metal; and (3) liners as metal, ceramic, polyethylene, highly cross-linked polyethylene (HXP), or vitamin E-infused highly cross-linked polyethylene (HXPE). A total of 64 eligible RCTs with different bearings were assessed. Overall inconsistency and heterogeneity were acceptable.

RESULTS

In the 10 years follow-up, metal-on-polythene and ceramic-on-polythene bearings with small heads showed higher risk for revisions compared with metal-on-HXP and ceramic-on-HXP bearings with small heads. Similarly, only metal or ceramic-on-polythene bearings with small heads showed inferiority in HHS compared with other bearings. Conventional polyethylene liners showed higher linear wear rates compared with HXP, HXPE, and ceramic liners at 5 and 10 years after surgery, while metal-on-metal and ceramic-on-metal bearings showed higher serum level of cobalt and chromium.

CONCLUSION

Bearings containing HXP, HXPE, and ceramic liners showed comparable survivorship and hip function at follow-up of 5 and 10 years. Hard-on-hard bearings containing metal had higher serum level of metal ions than others. Bearings containing conventional polyethylene had worse performance in terms of implant survival, hip function, and wear rates.

LEVEL OF EVIDENCE

Level I.

A network meta-analysis of immunotherapy-based treatments for advanced nonsquamous non-small cell lung cancer

Introduction: In the absence of head-to-head trials comparing immunotherapies for advanced nonsquamous non-small-cell lung cancer (NsqNSCLC), a network meta-analysis (NMA) was conducted to compare the relative efficacy of these treatments. Materials & methods: A systematic literature review of randomized controlled trials evaluating first-line-to-progression and second-line treatments for advanced NsqNSCLC informed Bayesian NMAs for overall survival (OS) and progression-free survival (PFS) end points. Results: Among first-line-to-progression treatments, pembrolizumab + pemetrexed + platinum showed the greatest OS benefit versus other regimens and a PFS benefit versus all but three regimens. Among second-line treatments, an OS benefit was seen for atezolizumab, nivolumab and pembrolizumab versus docetaxel. Conclusion: Pembrolizumab + pemetrexed + platinum showed the maximum OS benefit in the first-line setting. In the second-line setting, anti-PD-1/anti-PD-L1 monotherapies were better than docetaxel.

Comparison between ceramic-on-polyethylene versus metal-on-polyethylene prostheses in Total Hip Arthroplasties: a systematic review and meta-analysis

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field to standardize how to conduct, and to assist in the reasoning and decision-making of doctors. The information provided by this project must be critically evaluated by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical condition of each patient.

Analysis of biomechanical gait parameters in patients after total hip replacement operated via anterolateral approach depending on size of the femoral head implant: retrospective matched-cohort study

INTRODUCTION

Total hip replacement (THR) is considered one of the most effective medical procedures in treatment of osteoarthritis. Since its introduction, there has been a worldwide debate over proper implant selection in terms of size, bearing type and shape. Following study was designed to assess the importance of femoral head size in long-term follow-up.

MATERIALS AND METHODS

A cohort of 30 patients with primary end stage osteoarthritis who underwent total hip replacement was analysed retrospectively. A homogenous group was chosen with no major differences in BMI. Patients' gait parameters were measured in a biomechanics laboratory using the 3D BTS Smart system. WOMAC and VAS questionnaires were used to assess patient reported outcome.

RESULTS

The subgroup with larger implant head size had several outcomes significantly superior to the subgroup with standard head size and non-inferior to healthy hips. Following variables were measured during this study: time of support phase, time of swing phase, double support time, walking hip extension angle.

CONCLUSIONS

Use of larger sized femoral heads during THR gives better results in terms of gait pattern. Since restoring the gait pattern is one of the aspects of rehabilitation and returning to daily activities it seems to be an important observation.

Comparison of Premium Technology Utilization in Total Hip Arthroplasty Between Safety-net Hospitals and Non-safety-net Hospitals

INTRODUCTION

The objective of our study was to investigate the association of safety-net hospital (SNH) status with the use of premium technologies in total hip arthroplasty (THA) using the American Academy of Orthopaedic Surgeons American Joint Replacement Registry.

METHODS

Premium technology was defined as having one or more of the following three characteristics: ceramic femoral head, dual mobility (DM) bearing, or surgery conducted with robotic assistance (RA). Patients of all ages were included and subdivided into ceramic femoral head, DM, and RA cohorts. SNH status (based on disproportionate share data), patient demographics, geographical region, hospital size, and teaching affiliation were assessed. Multivariate regression analysis was conducted to analyze any notable associations.

RESULTS

A total of 624,933 THAs between SNHs and non-SNHs were available for analysis. Based on the three different premium technology categories, there were 551,838 THAs for ceramic femoral head utilization analysis, 601,223 THAs for DM utilization analysis, and 199,250 THAs for RA utilization analysis. SNHs were associated with less use of DM and RA (odds ratio [OR] 0.53 P < 0.0001, 0.39 P < 0.0001, respectively). No difference was observed in ceramic femoral head utilization between SNHs and non-SNHs. Patient age was significantly associated with less utilization of all three premium THA technologies (ceramic: OR 0.43 P < 0.0001; DM: OR 0.93 P < 0.0001, RA: OR 0.89 P < 0.001). Teaching hospitals were significantly associated with increased utilization of premium THA technologies (ceramic: OR 1.23 P < 0.0001, DM: OR 1.62 P < 0.0001, RA: OR 5.33 P < 0.001).

CONCLUSION

Premium THA technologies are becoming increasingly used across the US healthcare system; however, that growth is not equal in hospitals with marginalized patient populations. The utilization of ceramic femoral heads is becoming increasingly common across healthcare systems suggesting that ceramic femoral heads may no longer be considered premium technology but rather standard THA care.

LEVEL OF EVIDENCE

Level III.

A Review of Biomaterials and Associated Performance Metrics Analysis in Pre-Clinical Finite Element Model and in Implementation Stages for Total Hip Implant System

Total hip replacement (THR) is a common orthopedic surgery technique that helps thousands of individuals to live normal lives each year. A hip replacement replaces the shattered cartilage and bone with an implant. Most hip implants fail after 10–15 years. The material selection for the total hip implant systems is a major research field since it affects the mechanical and clinical performance of it. Stress shielding due to excessive contact stress, implant dislocation due to a large deformation, aseptic implant loosening due to the particle propagation of wear debris, decreased bone remodeling density due to the stress shielding, and adverse tissue responses due to material wear debris all contribute to the failure of hip implants. Recent research shows that pre-clinical computational finite element analysis (FEA) can be used to estimate four mechanical performance parameters of hip implants which are connected with distinct biomaterials: von Mises stress and deformation, micromotion, wear estimates, and implant fatigue. In vitro, in vivo, and clinical stages are utilized to determine the hip implant biocompatibility and the unfavorable local tissue reactions to different biomaterials during the implementation phase. This research summarizes and analyses the performance of the different biomaterials that are employed in total hip implant systems in the pre-clinical stage using FEA, as well as their performances in in vitro, in vivo, and in clinical studies, which will help researchers in gaining a better understanding of the prospects and challenges in this field.

A Comparison of Revision Rates and Dislocation After Primary Total Hip Arthroplasty with 28, 32, and 36-mm Femoral Heads and Different Cup Sizes: An Analysis of 188,591 Primary Total Hip Arthroplasties

This article was updated on August 17, 2022, because of previous errors, which were discovered after the preliminary version of the article was posted online. On page 1462, in the first sentence of the Abstract section entitled "Results," the phrase that had read "and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003), but more dislocations than 32-mm heads (HR for >2 weeks = 2.25 [95% CI, 1.13 to 4.49]; p = 0.021)" now reads "and 36-mm heads had fewer dislocations than 28-mm (HR = 0.33 [95% CI, 0.16 to 0.68]; p = 0.003) and 32-mm heads (HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88]; p = 0.021)." On page 1468, in the last sentence of the section entitled "Acetabular Components with a Diameter of <51 mm," the phrase that had read "and HR for ≥2 weeks = 2.25 [95% CI, 1.13 to 4.49; p = 0.021]) ( Fig. 3 )" now reads "and HR for ≥2 weeks = 0.44 [95% CI, 0.22 to 0.88; p = 0.021]) ( Fig. 3 )." Finally, on page 1466, in the upper right corner of Figure 3 , under "32mm vs 36mm," the second line that had read "2Wks+: HR=2.25 (1.13, 4.49), p=0.021" now reads "2Wks+: HR=0.44 (0.22, 0.88), p= 0.021."

Surgical therapy in osteoarthritis

OBJECTIVE

To provide an evidence-based overview of the different surgical procedures in osteoarthritis (OA).

DESIGN

This narrative review reports on surgical therapies (1) for severe, end stage OA and (2) of surgical options aiming to possibly reduce OA development earlier in the course of the disease.

RESULTS

Surgical practice guidelines provide evidence-based recommendations to assist in the clinical decision-making. Total joint arthroplasty represents the only valuable, established surgical option for severe, end stage OA. For hip and knee OA, it is by far the most common surgical procedure and provides considerable pain relief, functional restoration, and improved quality of life. Surgical therapy aiming to postpone OA essentially addresses extra- or intraarticular pre-osteoarthritic deformities, defined as congenital or acquired disturbances of the joint structure that adversely affect its function. Approaches in this category include osteotomies and different cartilage repair procedures such as osteochondral autograft and allograft transfer, marrow stimulation techniques, and autologous chondrocyte implantation. However, they are not only less commonly performed than arthroplasty, but the scientific clinical evidence in favour of this type of surgery to reduce the long-term risk of developing OA is considerably reduced.

CONCLUSION

Total knee and hip arthroplasty are two of the most successful procedures in all of medicine. As the progression of this insidious disease is often asymptomatic and slow, it is imperative to judge reparative procedures at their potential to reduce OA development at long-term, besides their primary clinical outcomes. Evidence-based guidelines provide a valuable tool for high-quality surgical decision making in OA.

UK poSt Arthroplasty Follow-up rEcommendations (UK SAFE): what does analysis of linked, routinely collected national data sets tell us about mid-late term revision risk after hip replacement? Retrospective cohort study

OBJECTIVE

To identify patients at risk of mid-late term revision of hip replacement to inform targeted follow-up.

DESIGN

Analysis of linked national data sets from primary and secondary care (Clinical Practice Research Datalink (CPRD-GOLD); National Joint Registry (NJR); English Hospital Episode Statistics (HES); Patient-Reported Outcome Measures (PROMs)).

PARTICIPANTS

Primary elective total hip replacement (THR) aged≥18.

EVENT OF INTEREST

Revision surgery≥5 years (mid-late term) after primary THR.

STATISTICAL METHODS

Cox regression modelling to ascertain risk factors of mid-late term revision. HR and 95% CI assessed association of sociodemographic factors, comorbidities, medication, surgical variables and PROMs with mid-late term revision.

RESULTS

NJR-HES-PROMs data were available from 2008 to 2011 on 142 275 THR; mean age 70.0 years and 61.9% female. CPRD GOLD-HES data covered 1995-2011 on 17 047 THR; mean age 68.4 years, 61.8% female. Patients had minimum 5 years postprimary surgery to end 2016. In NJR-HES-PROMS data, there were 3582 (2.5%) revisions, median time-to-revision after primary surgery 1.9 years (range 0.01-8.7), with 598 (0.4%) mid-late term revisions; in CPRD GOLD, 982 (5.8%) revisions, median time-to-revision 5.3 years (range 0-20), with 520 (3.1%) mid-late term revisions.Reduced risk of mid-late term revision was associated with older age at primary surgery (HR: 0.96; 95% CI: 0.95 to 0.96); better 6-month postoperative pain/function scores (HR: 0.35; 95% CI: 0.27 to 0.46); use of ceramic-on-ceramic (HR: 0.73; 95% CI: 0.56 to 0.95) or ceramic-on-polyethylene (HR: 0.76; 95% CI: 0.58 to 1.00) bearing surfaces.Increased risk of mid-late term revision was associated with the use of antidepressants (HR: 1.32; 95% CI: 1.09 to 1.59), glucocorticoid injections (HR: 1.33; 95% CI: 1.06 to 1.67) and femoral head size≥44 mm (HR: 2.56; 95% CI: 1.09 to 6.02)No association of gender, obesity or Index of Multiple Deprivation was observed.

CONCLUSION

The risk of mid-late term THR is associated with age at primary surgery, 6-month postoperative pain and function and implant factors. Further work is needed to explore the associations with prescription medications observed in our data.

The association between surgeon grade and risk of revision following total hip arthroplasty : an analysis of National Joint Registry data

AIMS

Total hip arthroplasties (THAs) are performed by surgeons at various stages in training with varying levels of supervision, but we do not know if this is safe practice with comparable outcomes to consultant-performed THA. Our aim was to examine the association between surgeon grade, the senior supervision of trainees, and the risk of revision following THA.

METHODS

We performed an observational study using National Joint Registry (NJR) data. We included adult patients who underwent primary THA for osteoarthritis, recorded in the NJR between 2003 and 2016. Exposures were operating surgeon grade (consultant or trainee) and whether or not trainees were directly supervised by a scrubbed consultant. Outcomes were all-cause revision and the indication for revision up to ten years. We used methods of survival analysis, adjusted for patient, operation, and healthcare setting factors.

RESULTS

We included 603,474 THAs, of which 58,137 (9.6%) procedures were performed by a trainee. There was no association between surgeon grade and all-cause revision up to ten years (crude hazard ratio (HR) 1.00 (95% confidence interval (CI) 0.94 to 1.07); p = 0.966), a finding which persisted with adjusted analysis. Fully adjusted analysis demonstrated an association between trainees operating without scrubbed consultant supervision and an increased risk of all-cause revision (HR 1.10 (95% CI 1.00 to 1.21); p = 0.045). There was an association between trainee-performed THA and revision for instability (HR 1.14 (95% CI 1.01 to 1.30); p = 0.039). However, this was not observed in adjusted models, or when trainees were supervised by a scrubbed consultant.

CONCLUSION

Within the current training system in England and Wales, appropriately supervised trainees achieve comparable THA survival to consultants. Trainees who are supervised by a scrubbed consultant achieve superior outcomes compared to trainees who are not supervised by a scrubbed consultant, particularly in terms of revision for instability. Cite this article: Bone Joint J 2022;104-B(3):341-351.

Fourth-Generation Ceramic Head Fracture in Dual Mobility Total Hip Arthroplasty: A Case Report

INTRODUCTION

Rare cases of Biolox® delta ceramic head fractures in ceramic-on-polyethylene bearings have been reported in the literature. Virtually none of these catastrophic injuries have been documented in dual mobility constructs.

CASE REPORT

We report a case of fourth-generation delta ceramic head fracture 4.5 years after implantation in a dual mobility total hip replacement constructs as a result of a ground-level fall. The patient underwent revision arthroplasty with another delta ceramic dual mobility construct and was able to return to work in custodial services 2 weeks after the revision procedure.

CONCLUSION

In summary, we presented an extremely uncommon case of a fractured fourth generation, Biolox® delta ceramic head in a dual mobility total hip arthroplasty (THA), as a result of a ground-level fall. The patient underwent successful revision surgery to another dual mobility delta ceramic THA. Despite substantial advances in ceramic materials, catastrophic failure of 4th generation ceramic head components can still occur even in dual mobility constructs and require revision arthroplasty surgery.

The Olympia anatomic polished cemented stem is associated with a high survivorship, excellent hip-specific functional outcome, and high satisfaction levels: follow-up of 239 consecutive patients beyond 15 years

INTRODUCTION

The Olympia femoral stem is a stainless steel, anatomically shaped, polished and three-dimensionally tapered implant designed for use in cemented total hip arthroplasty (THA). The primary aim of this study was to determine the long-term survivorship, radiographic outcome, and patient-reported outcome measures (PROMs) of the Olympia stem.

PATIENTS AND METHODS

Between May 2003 and December 2005, 239 patients (264 THAs) underwent a THA with an Olympia stem in our institution. Patient-reported outcome measures were assessed using the Oxford Hip Score (OHS), EuroQol-5 dimensions (EQ-5D) score, and patient satisfaction at mean 10 years following THA. Patient records and radiographs were then reviewed at a mean of 16.5 years (SD 0.7, 15.3-17.8) following THA to identify occurrence of complications or revision surgery for any cause following surgery. Radiographs were assessed for lucent lines and lysis according to Gruen's zones RESULTS: Mean patient age at surgery was 68.0 years (SD 10.9, 31-93 years). There were 156 women (65%, 176 THAs). Osteoarthritis was the indication for THA in 204 patients (85%). All cause stem survivorship at 10 years was 99.2% (95% confidence interval [CI], 97.9%-100%) and at 15 years was 97.5% (94.6%-100%). The 15-year stem survival for aseptic loosening was 100%. Analysis of all-cause THA failure demonstrated a survivorship of 98.5% (96.3%-100%) at 10 years and 95.9% (92.4%-99.4%) at 15 years. There were 9 THAs with non-progressive lucent lines in a single Gruen zone and 3 had lines in two zones, and no patient demonstrated signs for lysis. At a mean of 10-year (SD 0.8, 8.7-11.3) follow-up, mean OHS was 39 (SD 10.3, range 7-48) and 94% of patients reported being very satisfied or satisfied with their THA.

CONCLUSIONS

The Olympia stem demonstrated excellent 10-year PROMs and very high rates of stem survivorship at final follow-up beyond 15 years.

Outcome of revision surgery in recurrent dislocation of primary total hip arthroplasty

BACKGROUND

The cause of recurrent dislocation following primary total hip arthroplasty (THA) is multifactorial. A re-dislocation rate of up-to 34% following revision is reported. The aim of this study was to determine the re-dislocation rates following revision for recurrent THR dislocation.

METHODOLOGY

Patients who underwent revision for recurrent dislocation between January 2008 and January 2015 were identified. We identified the date and type of primary implant, overall number and reasons for dislocation, revision implant details and complication data.

RESULTS

Over an 8-year period, 24 patients underwent revision. The median age was 77 (68-85) years, median time to first dislocation was 78 (23-160) months and median number of dislocations was 3 (2-4) with a mean follow-up of 18 months. Socket Mal-Orientation (10) and Abductor deficiency (5) were the main causes of recurrent dislocation. 21 patients (88%) underwent revision of both components, 1 patient underwent isolated cup revision and 2 patients had revision of acetabular component with insertion of a BioBall. There were no dislocations within 90 days of revision surgery. 4 patients had late dislocations (3 recurrent, 1 isolated). There was no significant increase risk of dislocation after revision surgery in the neck of femur group (p = 0.467).

CONCLUSIONS

We report favourable outcomes for revision of both components for recurrent dislocation with no dislocations within 90 days. The overall late dislocation rate was 16.7%, however, these patients have settled following closed reduction. Due to its multifactorial aetiology, both component revision can be considered in this patient population.

Irisin recouples osteogenesis and osteoclastogenesis to protect wear-particle-induced osteolysis by suppressing oxidative stress and RANKL production

The disruption of bone homeostasis with the decrease in osteoblastic bone formation and facilitated osteoclastic bone resorption is the leading cause of periprosthetic osteolysis. Accumulative studies have indicated that irisin has the function of maintaining and rebalancing bone homeostasis. In this study, we explored the protective effect of irisin on wear-particle-induced osteolysis in mice. The results showed that irisin effectively inhibited titanium (Ti) particle-induced calvarial osteolysis, supported by a lower bone loss and existence of more collagen, compared with the ones stressed by Ti particles. Further analysis demonstrated that irisin not only rescued Ti-particle-impaired osteogenesis derived from bone mesenchymal stem cells (BMSCs) but also alleviated the increase in wear-particle-induced nuclear factor-κB ligand (RANKL) secreted by BMSCs-derived osteoblasts, which consequently restrained the activation of osteoclasts. Meanwhile, irisin inhibited osteoclastogenesis by the direct inactivation of reactive oxygen species (ROS) signaling. These results revealed that irisin functions to fight against osteolysis caused by wear particles through rebalancing the periprosthetic bone homeostasis microenvironment, which may provide a potential therapeutic strategy for the management of osteolysis and induced prosthetic loosening.

Role of real-world digital data for orthopedic implant automated surveillance: a systematic review

INTRODUCTION

Data collection automation through the reuse of real-world digital data from clinical data warehouses (CDW) could represent a great opportunity to improve medical device monitoring. For instance, this approach is starting to be used for the design of automated decision support systems for joint replacement monitoring. However, a number of obstacles remains, such as data quality and interoperability through the use of common and regularly updated terminologies, and the use of a Unique Device Identifier (UDI).

AREAS COVERED

To present the existing models of automated surveillance of orthopedic devices, a systematic review of initiatives using real-world digital health data to monitor joint replacement surgery was performed following the PRISMA 2020 guidelines. The main objective was to identify the data sources, the target populations, the population size, the device location, and the main results of studies on such initiatives.

EXPERT OPINION

Analysis of the identified studies showed that real-world digital data offer many opportunities for improving the automation of monitoring in orthopedics. The contribution of real-world data, especially through natural language processing, UDI use in CDW and the integration of device databases, is needed for automated and more robust health surveillance.

Curculigoside Protects against Titanium Particle-Induced Osteolysis through the Enhancement of Osteoblast Differentiation and Reduction of Osteoclast Formation

Wear particle-induced periprosthetic osteolysis is mainly responsible for joint replacement failure and revision surgery. Curculigoside is reported to have bone-protective potential, but whether curculigoside attenuates wear particle-induced osteolysis remains unclear. In this study, titanium particles (Ti) were used to stimulate osteoblastic MC3T3-E1 cells in the presence or absence of curculigoside, to determine their effect on osteoblast differentiation. Rat osteoclastic bone marrow stromal cells (BMSCs) were cocultured with Ti in the presence or absence of curculigoside, to evaluate its effect on osteoclast formation in vitro. Ti was also used to stimulate mouse calvaria to induce an osteolysis model, and curculigoside was administrated to evaluate its effect in the osteolysis model by micro-CT imaging and histopathological analyses. As the results indicated, in MC3T3-E1 cells, curculigoside treatment attenuated the Ti-induced inhibition on cell differentiation and apoptosis, increased alkaline phosphatase activity (ALP) and cell mineralization, and inhibited TNF-α, IL-1β, and IL-6 production and ROS generation. In BMSCs, curculigoside treatment suppressed the Ti-induced cell formation and suppressed the TNF-α, IL-1β, and IL-6 production and F-actin ring formation. In vivo, curculigoside attenuated Ti-induced bone loss and histological damage in murine calvaria. Curculigoside treatment also reversed the RANK/RANKL/OPG and NF-κB signaling pathways, by suppressing the RANKL and NF-κB expression, while activating the OPG expression. Our study demonstrated that curculigoside treatment was able to attenuate wear particle-induced periprosthetic osteolysis in in vivo and in vitro experiments, promoted osteoblastic MC3T3-E1 cell differentiation, and inhibited osteoclast BMSC formation. It suggests that curculigoside may be a potential pharmaceutical agent for wear particle-stimulated osteolysis therapy.

The efficacy of acupuncture and moxibustion for early and middle-stage osteonecrosis of the femeral head: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Osteonecrosis of the femeral head (ONFH) occurs predominantly in young- and middle-aged people, and the disability rate is high in the late stage of the disease and most patients have to undergo total hip replacement. Clinically, increasing attention is paid to intervening early and middle-stage ONFH so as to delay its progress. Acupuncture and moxibustion (AM) is a unique method for treating ONFH in China. This study aims to summarize the advantages of AM for the treatment of ONFH.

METHODS

A comprehensive literature search was conducted on the database with languages of English and Chinese. The medical subject titles used are "Osteonecrosis of the femoral head" and "acupuncture and moxibustion." Related words in the title or abstract including but were not limited to "necrosis of the femoral head," "avascular necrosis of the femoral head," "ischemic necrosis of the femoral head," "caput femoris necrosis," "bone paralysis," "bone erosion," and "bone atrophy."

RESULTS

Nine randomized controlled trials were identified in this meta-analysis that included 630 subjects. Meta-analysis showed that the trial group that treated with conventional therapy combined with AM had a higher effective rate (Z = 2.27 P = 0.02) and excellent and good rate (Z = 4.85 P < 0.00001) and Harris hip function score (HHS) (Z = 2.31 P = 0.02) and lower incidence of related adverse reactions during treatment (Z = 2.82 P = 0.005) compared with the control group that treated with conventional therapy alone.

CONCLUSIONS

AM for early and middle-stage ONFH is an effective and relatively safe intervention, which can improve the effective rate and excellent and good rate and HHS, and reduce the adverse reaction rate. Clinically, early and middle-stage ONFH can be intervened by combining with AM while taking conventional therapy to improve the efficacy.

Cost-effectiveness analyses comparing cemented, cementless, hybrid and reverse hybrid fixation in total hip arthroplasty: a systematic overview and critical appraisal of the current evidence

Background: This study aims to present an overview and critical appraisal of all previous studies comparing costs and outcomes of the different modes of fixation in total hip arthroplasty (THA). A secondary aim is to provide conclusions regarding the most cost-effective mode of implant fixation per gender and age-specific population in THA, based on high quality studies.Methods: A systematic search was conducted to identify cost-effectiveness analyses (CEAs) comparing different modes of implant fixation in THA. Analysis of results was done with solely CEAs that had a high methodological quality.Results: A total of 12 relevant studies were identified and presented, of which 5 were considered to have the methodological rigor for inclusion in the analysis of results. These studies found that either cemented or hybrid fixation was the most cost-effective implant fixation mode for most age- and gender-specific subgroups.Conclusion: Currently available well performed CEAs generally support the use of cemented and hybrid fixation for all age-groups relevant for THA and both genders. However, these findings were mainly based on a single database and depended on assumptions made in the studies' methodology. Issues discussed in this paper have to be considered and future work is needed.

[Tribology in hip arthroplasty : Benefits of different materials]

When it comes to total hip replacements, choosing the suitable material combination is of clinical relevance. The present review article examines the technical differences in wear and corrosion of the relevant material combinations of ceramics, metals, ceramized metals and various types of polyethylene. The material characteristics, which were often tested under standardized conditions in the laboratory, are compared with clinical results on the basis of evidence-graded clinical studies and on the basis of register studies. This article thus represents an up-to-date snapshot of the expectations and actual clinical outcomes of the present choice of material combinations. It shows that some tendencies from the field of materials research, e.g. with regard to cross-linked polyethylene, coincide with observations from practical clinical experience, while for other materials, a proven technical superiority has not yet been confirmed as an evident advantage in clinical practice.

Ceramic-on-ceramic total hip arthroplasty is superior to metal-on-conventional polyethylene at 20-year follow-up: A randomised clinical trial

BACKGROUND

Metal-on-conventional polyethylene (MoPc) bearing wear-related biological reactions in total hip arthroplasty (THA) continue to raise concerns among young, active patients. Ceramic-on-ceramic (CoC) bearings may offer improved outcomes in this patient population.

QUESTIONS/PURPOSES

The aim of this study was to determine if, more than 20years postoperatively, there is a difference between MoPc and CoC THA in terms of (1) survivorship, (2) related complications, (3) radiographic signs of wear, and (4) functional scores.

HYPOTHESIS

CoC bearing THAs have superior clinical results compared to MoPc THAs.

PATIENTS AND METHODS

A total of 140 hips in 116 patients with a mean age of 42years were randomised to receive CoC or MoPc THA between 1996 and 2001. Sixty-nine hips in 58 patients received MoP and 71 hips in 68 patients received CoC. Revision rate, WOMAC score, and radiological signs of osteolysis and loosening were compared at last follow-up.

RESULTS

After a mean follow-up of 21years (19-23), 40 patients (48 THAs; 34%) had died and 6 patients (6 THAs; 4%) were lost to follow-up. Aseptic revision rate was significantly higher in the MoPc group (17/69; 24.6%) versus CoC (2/71; 2.8%; p<0.001). Kaplan-Meier survivorship estimator with revision for aseptic reasons was 73.6% (95% CI: 63.3-84.9%) for MoPc and 96.9% (95% CI: 92.8-100%) for CoC (p<0.001). On radiographic evaluation, 13% (3/23) MoPc were considered loose versus no CoC, and 61% (14/23) MoPc versus 6% (2/33) CoC showed osteolytic signs (p<0.001). CoC had better mean WOMAC scores than MoPc (11.0 vs. 19.4; p=0.048). No ceramic fracture was observed.

CONCLUSION

In this RCT, CoC bearings provided excellent results and were safer than MoPc bearings at more than 20-year follow-up. The long-term in vivo behaviour of CoC bearing makes it a great THA option for middle-aged patients and should be compared to newer polyethylene bearings.

LEVEL OF EVIDENCE

I.

Choice between implants in knee replacement: protocol for a Bayesian network meta-analysis, analysis of joint registries and economic decision model to determine the effectiveness and cost-effectiveness of knee implants for NHS patients-The KNee Implant Prostheses Study (KNIPS)

INTRODUCTION

Knee replacements are highly successful for many people, but if a knee replacement fails, revision surgery is generally required. Surgeons and patients may choose from a range of implant components and combinations that make up knee replacement constructs, all with potential implications for how long a knee replacement will last. To inform surgeon and patient decisions, a comprehensive synthesis of data from randomised controlled trials is needed to evaluate the effects of different knee replacement implants on overall construct survival. Due to limited follow-up in trials, joint registry analyses are also needed to assess the long-term survival of constructs. Finally, economic modelling can identify cost-effective knee replacement constructs for different patient groups.

METHODS AND ANALYSIS

In this protocol, we describe systematic reviews and network meta-analyses to synthesise evidence on the effectiveness of knee replacement constructs used in total and unicompartmental knee replacement and analyses of two national joint registries to assess long-term outcomes. Knee replacement constructs are defined by bearing materials and mobility, constraint, fixation and patella resurfacing. For men and women in different age groups, we will compare the lifetime cost-effectiveness of knee replacement constructs.

ETHICS AND DISSEMINATION

Systematic reviews are secondary analyses of published data with no ethical approval required. We will design a common joint registry analysis plan and provide registry representatives with information for submission to research or ethics committees. The project has been assessed by the National Health Service (NHS) REC committee and does not require ethical review.Study findings will be disseminated to clinicians, researchers and administrators through open access articles, presentations and websites. Specific UK-based groups will be informed of results including National Institute for Health Research and National Institute for Health and Care Excellence, as well as international orthopaedic associations and charities. Effective dissemination to patients will be guided by our patient-public involvement group and include written lay summaries and infographics.

PROSPERO REGISTRATION NUMBER

CRD42019134059 and CRD42019138015.

Standard table direct anterior approach within an early discharge protocol for cementless total hip arthroplasty: experience from a Japanese hospital

AIMS

Clinical and economic outcomes associated with an early discharge protocol for cementless total hip arthroplasty (THA) via a direct anterior approach (DAA) on a standard table without a dedicated traction table) were assessed. These outcomes were compared against a benchmark of THA care approximated from a national database.

MATERIALS AND METHODS

This retrospective, observational, comparative cohort study evaluated 250 patients receiving THA with a standard table DAA approach under an early discharge protocol at a medical center in Japan between 2016 and 2017 (intervention). Patients were propensity score-matched to a standard care control group comprised of THA patients within the Japan Medical Data Center database. A generalized linear model (GLM) using gamma distribution with log-link compared hospital length of stay (LOS) and total cost. Post-operative function and pain (Japanese Orthopaedic Association hip score [JOA] and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire [JHEQ]) were assessed for DAA patients.

RESULTS

After propensity score matching, 239 patients were included in each cohort. The patients in the intervention and control group were comparable in regard to age, gender, comorbidities, and procedure year. Adjusted hospital LOS for DAA as part of an early discharge protocol was significantly shorter than for control patients (4.76 vs. 25.36 days). Adjusted total costs were significantly lower (29%) for the intervention group (¥1,613,800 vs. ¥2,254,757; US$14,390 vs. US$20,105). The 3-month follow-up complication rate was 0.42% (superficial infection) for intervention vs. 3.35%. The intervention group had no readmissions and post-operative function and pain scores significantly improved (JHEQ pain score 7.2 ± 5.0 to 24.2 ± 4.6, JOA 48.4 ± 12.8 to 94.3 ± 7.0; p-value < .001).

LIMITATIONS

The study is not randomized and EMR and administrative claims data may lack information (i.e. some clinical variables) required for inference. Also, the data may not represent the whole Japanese population.

CONCLUSIONS

An early discharge protocol demonstrated compatibility with standard table DAA in a Japanese hospital, providing cost savings, while maintaining reliable clinical outcomes.

Fixation Method and Subsequent Revision Rates for Elective Primary Hip Arthroplasty in People Aged 70 Years and Older: Analysis of National Administrative Data Sets by the UK Getting It Right First Time Program

BACKGROUND

We aimed to understand the role of fixation method in predicting subsequent revision rates in people aged 70 years and older undergoing elective primary total hip arthroplasty (THA) within the UK National Health Service (NHS).

METHODS

Data on elective primary THAs conducted in people aged 70 years and older between April 1, 2012, and March 31, 2018, and subsequent revisions conducted up to March 31, 2019, were extracted from the Hospital Episodes Statistics database for all NHS procedures in England. A flexible parametric competing risks model was used to identify the role of fixation method in predicting revision and adjust for age, sex, frailty, year of surgery, and all-cause mortality.

RESULTS

Data were available for 190,656 procedures. Crude revision rates at 1-7 years follow-up in those who had cemented, hybrid/reverse hybrid, and uncemented fixation were 1.8%, 1.8%, and 2.3%, respectively. There was a high level of variation between NHS trusts in the proportionate use of fixation method. The differences in the hazard of revision between uncemented and cemented fixation (hazard ratio, 1.238 [95% confidence interval, 1.148-1.336]) and hybrid/reverse hybrid fixation (hazard ratio, 1.184 [95% confidence interval, 1.082-1.297]) were both significant. In secondary analysis, there was evidence that revision rates in trusts where uncemented fixation predominated were not significantly lower for uncemented fixation compared to all other fixation methods.

CONCLUSIONS

Revision rates were significantly higher for elective primary THA in people aged 70 years and older who have uncemented fixation, compared to those who had cemented and hybrid/reverse hybrid fixation.

Diagnostic Value of MRI Lamellated Hyperintense Synovitis in Periprosthetic Infection of Hip

OBJECTIVE

To investigate the correlation between magnetic resonance imaging (MRI) lamellated hyperintense synovitis and periprosthetic infection of hip arthroplasty and estimate its value in the diagnosis of infection after hip replacement.

METHODS

A retrospective analysis of 50 patients who underwent MRI from January 2016 to June 2019 after hip replacement was performed. The MRI scanning was performed with a 1.5T clinical imaging unit using SEMAC protocols. A total of 25 patients (cohort 1) showed infected total hip arthroplasty, and 25 patients had non-infected arthroplasty as controls (cohort 2). Two musculoskeletal radiologists, blinded to the clinical diagnosis, reviewed all the images for the presence of lamellated hyperintense synovitis independently. The cases were rereviewed by each reader after 2 weeks. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated using the first reads. The Kappa statistic was used to assess inter-observer and intra-observer reliability.

RESULTS

The incidence of lamellated hyperintense synovitis was 76%-88% in the experimental group and 8%-16% in the control group. The sensitivity of lamellated hyperintense synovitis for infection was 0.80-0.88 (95% confidence interval [CI]:0.59 - 0.97), the specificity was 0.84~0.92 (95% CI: 0.64  -0.99), the positive predictive value 0.83-0.92 (95% CI: 0.67 - 0.98), the negative predictive value 0.81 - 0.88 (95% CI: 0.65 - 0.96). The agreement between two readers was substantial (Kappa = 0.76, 95% CI: 0.58 - 0.94, P < 0.05). There were moderate inter-observer agreements for both readers, reader 1 (Kappa = 0.48, 95%CI: 0.23 - 0.72, P < 0.05) and reader 2 (Kappa = 0.44，95% CI: 0.19 - 0.69, P < 0.05).

CONCLUSION

In this cohort, the presence of lamellated hyperintense synovitis in the MRI of hip arthroplasty showed high sensitivity and specificity for infection. This sign had substantial intra-observer reliability and moderate inter-observer reliability in the classification of the synovial pattern.

False profile view is independently associated with serum metal levels in patients with metal-on-metal hip arthroplasty

PURPOSE

Elevated levels of serum metal ions can be found in some patients with metal-on-metal (MoM) hip replacements. This study seeks to identify whether there is a significant association between the contact patch to rim distance (CPRD) and the anterior center edge angle (ACEA), respectively, and serum cobalt (Co) and chromium (Cr) levels in patients treated with unilateral MoM hip replacements by using standing anteroposterior and false profile view radiographs.

METHODS

This is a retrospective analysis on 53 patients with either unilateral ReCap or M2a-Magnum MoM hip replacements operated in 2006 or 2007. Univariate linear regression and multivariable linear regression (MLR) analyses were performed using the CPRD and ACEA along with risk factors for elevated serum levels of Co and Cr previously suggested in the literature as explanatory variables. Serum Co and Cr were measured using inductively coupled plasma mass spectrometry.

RESULTS

The MLR model showed that the same three variables (gender, CPRD and ACEA) were significantly associated with serum levels of both Co and Cr explaining approximately half of the variation. A univariate analysis showed a polynomial association between both anteversion angle and the ACEA with serum levels of Co and Cr. The vertex of the polynomial function was located at approximately 20° and 40°, respectively.

CONCLUSION

Gender, CPRD and ACEA are independently associated with serum levels of Co and Cr. Both ACEA and anteversion angles have optimae associated with low serum metal levels which may be useful for post-surgery evaluation of cup positioning.

Does vitamin E highly-crosslinked polyethylene convey an advantage in primary total hip replacement? A systematic review and meta-analysis

BACKGROUND

Vitamin E highly cross-linked polyethylene (HXLPE) was developed to reduce wear in total hip replacement (THR). This formal systematic review and meta-analysis aimed to provide independent synthesis of wear characteristics of Vitamin E treated HXLPE compared to HXPLE/UHMWPE. Secondary outcome measures were differences in revision rates and functional scores.

METHODS

We performed a formal systematic review as per PRISMA guidelines; literature searches were conducted on 14 November 2017 (MEDLINE, Embase on Ovid, and the Cochrane Library). We included randomised controlled trials, analyses of joint registries, and case-controlled studies of primary THR comparing cups with a vitamin E HXLPE bearing with bearing surfaces made from other types of polyethylene. Initial screening was performed by 2 independent assessors; disagreement resolved in discussion with a third reviewer. Studies were evaluated using the Cochrane risk of bias tool. Data extraction permitted meta-analysis.

RESULTS

372 studies were identified on initial screening, 5 studies met the eligibility criteria. There was no significant heterogeneity between studies. There was variable risk of bias. At a mean of 35 (range 20-60) months, Vitamin E HXLPE had significant advantages over highly cross-linked polyethylene with regards total femoral head penetration (p = 0.004). Given the RSA measurement errors this may not be clinically significant.There were neither significant differences in revision rates nor Harris Hip Scores (p = 0.06).

CONCLUSION

At a minimum of 3 years follow-up there was reduced total femoral head penetration for vitamin E HXLPE over HXLPE. This bearing surface does not, as yet, have clinically significant advantages in terms of revision rates or patient function over HXLPE.

Recent update on crosslinked polyethylene in total hip arthroplasty

More than two decades after their clinical introduction, crosslinked polyethylenes (XLPE) have been widely adopted. Though concerns were initially raised regarding oxidation and brittleness, on a large scale, the first generation of XLPE continues to be highly effective 15 years after the surgery, even in a young and active population. Remelted XLPE might display lower wear rates than annealed XLPE. Second generation XLPEs, not only including sequentially irradiated and annealed but also associated with antioxidants, demonstrate encouraging short- to mid-term results. Registry data support clinical trial reports. Even in less favorable settings (lipped liners, dual mobility cups, revision surgery, hip resurfacing) results are promising. However, failures (fractures) have already been described. Therefore, a high level of surveillance remains crucial.

Current Preclinical Testing of New Hip Arthroplasty Technologies Does Not Reflect Real-World Loadings: Capturing Patient-Specific and Activity-Related Variation in Hip Contact Forces

BACKGROUND

Total hip arthroplasty (THA) implants are routinely tested for their tribological performance through regulatory preclinical wear testing (eg, ISO-14242). The standardized loading conditions defined in these tests consist of simplified waveforms, which do not specifically represent in vivo loads in different groups of patients. The aim of this study is to investigate, through musculoskeletal modeling, patient-specific and activity-related variation in hip contact forces (HCFs) in a large cohort of THA patients during common activities of daily living (ADLs).

METHODS

A total of 132 THA patients participated in a motion-capture analysis while performing different ADLs, including walk, fast walk, stair ascent, and descent (locomotor); sit to stand, stand to sit, squat, and lunge (nonlocomotor). HCFs were then calculated using the AnyBody Modeling System and qualitatively compared across all activities. The influence of gender on HCFs was analyzed through statistical parametric mapping analysis.

RESULTS

Systematic differences were found in HCF magnitudes and individual components in both locomotor and nonlocomotor ADLs. The qualitative analysis of the ADLs revealed a large range and a large variability in forces experienced at the hip during different activities. Significant differences in the 3-dimensional loading patterns were observed between males and females across most activities.

CONCLUSION

THA patients present a large variability in the forces experienced at the hip joint during their daily life. The interpatient variation might partially explain the heterogeneity observed in implant survival rates. A more extensive preclinical implant testing standard under clinically relevant loading conditions has been advocated to better predict and avoid clinical wear problems.

Gross trunnion failure in metal on polyethylene total hip arthroplasty-a systematic review of literature

BACKGROUND

Multiple cases of dissociation of the head from the neck termed as gross trunnion failure (GTF) in total hip replacement have been described. Very little quantitative data is available for patient and implant factors associated and predisposing to this complication.

STUDY PURPOSE

To systematically review and analyze all studies which have gross trunnion failure in case of metal on polyethylene (MoP) total hip replacement.

METHODS

PubMed database was searched. We also performed a secondary search by pearling bibliography of all full text articles obtained. Predefined inclusion and exclusion criteria were used for abstract screening by two independent observers. A total 46 cases met our inclusion criteria. These were included in the final analysis and data was pooled.

RESULTS

Till date, 46 cases of GTF in MoP THR have been reported. The mean age at time of revision was 70.13 years (range 50 to 89 years). The mean time to revision surgery was 8.24 years (range 4.7 to 14 years). 91.4% cases were male. BMI was ≥ 25 in 38/41 cases and ≥ 30 in 21/41 cases. Pain (95.5%) and difficulty or inability to walk (97.7%) were the most common symptoms. A total of 19/44 cases described varying sounds like click, clunk, and pop before dislocation. Accolade TMZF/TMZF plus was the most common stem used in 34/46 cases. The stem neck angle was 127 degrees in 97% cases (32/33 cases). A positive neck offset of 4 mm or more was used in 91.1% cases (40/44 cases). The head size ≥ 36 mm in approximately 90% cases. The head material was cobalt chromium in all 45 cases, where data was available. Among the intra-operative findings, the most common findings were metallosis (41/44), black or brow coloured synovial fluid (21/44), pseudotumour (19/44), synovial hypertrophy (18/44), damage to the abductor musculature (17/44), proximal femoral osteolysis (5/44 cases), and heterotrophic ossification (2/44 cases). Histopathological analysis was available in 11 cases and was suggestive of fibrous tissue with chronic cellular infiltrate in all cases. The serum cobalt and chromium concentrations were raised above normal in 86.4% (19/22) and 21.7% cases (5/23) respectively.

CONCLUSIONS

Gross trunnion failure may not be as uncommon as was previously thought. A number potential associations and predisposing factors of this complication have been highlighted in this review. But due to small sample size and weak level of evidence, further studies are needed in this field.

Diagnosis and management of implant debris-associated inflammation

Introduction: Total joint replacement is one of the most common, safe, and efficacious operations in all of surgery. However, one major long-standing and unresolved issue is the adverse biological reaction to byproducts of wear from the bearing surfaces and modular articulations. These inflammatory reactions are mediated by the innate and adaptive immune systems.Areas covered: We review the etiology and pathophysiology of implant debris-associated inflammation, the clinical presentation and detailed work-up of these cases, and the principles and outcomes of non-operative and operative management. Furthermore, we suggest future strategies for prevention and novel treatments of implant-related adverse biological reactions.Expert opinion: The generation of byproducts from joint replacements is inevitable, due to repetitive loading of the implants. A clear understanding of the relevant biological principles, clinical presentations, investigative measures and treatments for implant-associated inflammatory reactions and periprosthetic osteolysis will help identify and treat patients with this issue earlier and more effectively. Although progressive implant-associated osteolysis is currently a condition that is treated surgically, with further research, it is hoped that non-operative biological interventions could prolong the lifetime of joint replacements that are otherwise functional and still salvageable.

Understanding the uptake of new hip replacement implants in the UK: a cohort study using data from the National Joint Registry for England and Wales

OBJECTIVES

Primary: describe uptake of new implant components (femoral stem or acetabular cup/shell) for total hip replacements (THRs) in the National Joint Registry for England and Wales (NJR). Secondary: compare the characteristics of: (a) surgeons and (b) patients who used/received new rather than established components.

DESIGN

Cohort of 618 393 primary THRs performed for osteoarthritis (±other indications) by 4979 surgeons between 2008 and 2017 in England and Wales from the NJR. We described the uptake of new (first recorded use >2008, used within 5 years) stems/cups, and variation in uptake by surgeons (primary objectives). We explored surgeon-level and patient-level factors associated with use/receipt of new components with logistic regression models (secondary objectives).

OUTCOMES

Primary outcomes: total number of new cups/stems, proportion of operations using new versus established components.

SECONDARY OUTCOMES

odds of: (a) a surgeon using a new cup/stem in a calendar-year, (b) a patient receiving a new rather than established cup/stem.

RESULTS

Sixty-eight new cups and 72 new stems were used in 47 606 primary THRs (7.7%) by 2005 surgeons (40.3%) 2008-2017. Surgeons used a median of one new stem and cup (25%-75%=1-2 both, max=10 cups, max=8 stems). Surgeons performed a median total of 22 THRs (25%-75%=5-124, range=1-3938) in the period 2008-2017. Surgeons used new stems in a median of 5.0% (25%-75%=1.3%-16.1%) and new cups in a median of 9.4% (25%-75%=2.8%-26.7%) of their THRs. Patients aged <55 years old versus those 55-80 had higher odds of receiving a new rather than established stem (OR=1.83, 95% CI=1.73-1.93) and cup (OR=1.31, 95% CI=1.25-1.37). Women had lower odds of receiving a new stem (OR=0.87, 95% CI=0.84-0.90), higher odds of receiving a new cup (OR=1.06, 95% CI=1.03-1.09).

CONCLUSIONS

Large numbers of new THR components have been introduced in the NJR since 2008. 40% of surgeons have tried new components, with wide variation in how many types and frequency they have been used.

Magnetic resonance imaging (MRI) versus single photon emission computed tomography (SPECT/CT) in painful total hip arthroplasty: a comparative multi-institutional analysis

OBJECTIVE

To investigate the value of MRI in comparison to single photon emission computed tomography (SPECT)/CT in patients with painful hip arthroplasties.

METHODS

A prospective, multi-institutional study was performed. Therefore, 35 consecutive patients (21 female, 14 male, mean age 61.8 ± 13.3 years) with 37-painful hip arthroplasties were included. A hip surgeon noted the most likely diagnosis based on clinical examination and hip radiographs. Then, MRI and SPECT/CT of the painful hips were acquired. MRI and SPECT/CT were assessed for loosening, infection, fracture, tendon pathology and other abnormalities. Final diagnosis and therapy was established by the hip surgeon after integration of MRI and SPECT/CT results. The value of MRI and SPECT/CT for diagnosis was assessed with a 3-point scale (1 = unimportant, 2 = helpful, 3 = essential).

RESULTS

Loosening was observed in 13/37 arthroplasties (6 shaft only, 6 cup only, 1 combined). Sensitivity, specificity, positive predictive value and negative predictive value for loosening of MRI were 86%/88%/60%/100% and of SPECT/CT 93%/97%/90%/100%, respectively. MRI and SPECT/CT diagnosed infection correctly in two of three patients and fractures in two patients, which were missed by X-ray. MRI detected soft tissue abnormalities in 21 patients (6 bursitis, 14 tendon lesions, 1 pseudotumor), of which only 1 tendon abnormality was accurately detected with SPECT/CT. All 5 arthroplasties with polyethylene wear were correctly diagnosed clinically and with both imaging modalities. MRI and SPECT/CT were judged as not helpful in 0/0%, as helpful in 16%/49% and essential in 84%/51%.

CONCLUSION

In patients with painful hip arthroplasty SPECT/CT is slightly superior to MR in the assessment of loosening. MRI is far superior in the detection of soft tissue, especially tendon pathologies.

ADVANCES IN KNOWLEDGE

To our knowledge this is the first prospective, multiinstitutional study which compares MRI with SPECT/CT in painful hip arthroplasties. We found that MRI is far superior in the detection of soft tissue pathologies, whereas SPECT/CT remains slightly superior regarding loosening.

To cement or not to cement acetabular cups in total hip arthroplasty: a systematic review and re-evaluation

INTRODUCTION

Total Hip Arthroplasty (THA) in the treatment of primary osteoarthritis of the hip has evolved to a very safe and cost-effective intervention with revision rates below 5% after 10 years. To this day, however, controversy remains on whether or not to cement the acetabular cup.

METHODS

A comprehensive PubMed search of the English literature for studies published between 2007 and 2018 was performed. Studies comparing the clinical (revision rate, functionality), radiological (wear) or economic (cost) differences between cemented (cemented stem with cemented cup) and hybrid (cemented stem with uncemented cup) prostheses for primary osteoarthritis of the hip were identified as eligible.

RESULTS

A total of 1032 studies were identified whereof twelve were included for qualitative synthesis. All studies concerning the risk of revision were based on registry data, covering a total of 365,693 cups. Cemented prostheses had a similar or lower risk of revision compared to hybrid prostheses in every study, but performed slightly worse on functionality and quality of life. While cemented prostheses were the cheapest option, hybrids were the most cost-effective.

DISCUSSION

The widespread preference for cementless fixation of the acetabulum cannot be explained by a superior survival of cementless or hybrid models. Irrespective of age, cemented fixation of the acetabulum remains the gold standard to which other techniques should be compared.

Medical device surveillance with electronic health records

Post-market medical device surveillance is a challenge facing manufacturers, regulatory agencies, and health care providers. Electronic health records are valuable sources of real-world evidence for assessing device safety and tracking device-related patient outcomes over time. However, distilling this evidence remains challenging, as information is fractured across clinical notes and structured records. Modern machine learning methods for machine reading promise to unlock increasingly complex information from text, but face barriers due to their reliance on large and expensive hand-labeled training sets. To address these challenges, we developed and validated state-of-the-art deep learning methods that identify patient outcomes from clinical notes without requiring hand-labeled training data. Using hip replacements-one of the most common implantable devices-as a test case, our methods accurately extracted implant details and reports of complications and pain from electronic health records with up to 96.3% precision, 98.5% recall, and 97.4% F1, improved classification performance by 12.8-53.9% over rule-based methods, and detected over six times as many complication events compared to using structured data alone. Using these additional events to assess complication-free survivorship of different implant systems, we found significant variation between implants, including for risk of revision surgery, which could not be detected using coded data alone. Patients with revision surgeries had more hip pain mentions in the post-hip replacement, pre-revision period compared to patients with no evidence of revision surgery (mean hip pain mentions 4.97 vs. 3.23; t = 5.14; p < 0.001). Some implant models were associated with higher or lower rates of hip pain mentions. Our methods complement existing surveillance mechanisms by requiring orders of magnitude less hand-labeled training data, offering a scalable solution for national medical device surveillance using electronic health records.

Hemiarthroplasty vs Total Hip Arthroplasty for the Management of Displaced Neck of Femur Fractures: A Systematic Review and Meta-Analysis

BACKGROUND

Displaced femoral neck fractures (DFNF) are common and can be treated with osteosynthesis, hemiarthroplasty (HA), or total hip arthroplasty (THA). There is no consensus as to which intervention is superior in managing DFNF.

METHODS

Studies were identified through a systematic search of the MEDLINE database, EMBASE database, and Cochrane Controlled Trials. Included studies were randomized or controlled trials (1966 to August 2018) comparing THA with HA for the management of DFNF. (https://www.crd.york.ac.uk/PROSPERO Identifier: CRD42018110057).

RESULTS

Seventeen studies were included totaling 1364 patients (660 THA and 704 HA). THA was found to be superior to HA in terms of risk of reoperation, Harris Hip Score and Quality of Life (Short Form 36). Overall, the risk of dislocation was greater in THA group than HA in the first 4 years, after which there was no difference. There was no difference between THA and HA in terms of mortality or infection.

CONCLUSION

Overall, THA appears to be superior to HA. THA should be the recommended intervention for DFNF in patients with a life expectancy >4 years and in patients younger than 80 years. However, both HA and THA are reasonable interventions in patients older than 80 years and with shorter life expectancy.

Cemented Exeter total hip arthroplasty with a 32 mm head on highly crosslinked polyethylene: Does age influence functional outcome, satisfaction, activity, stem migration, and periprosthetic bone mineral density?

Objectives

Our primary aim was to describe migration of the Exeter stem with a 32 mm head on highly crosslinked polyethylene and whether this is influenced by age. Our secondary aims were to assess functional outcome, satisfaction, activity, and bone mineral density (BMD) according to age.

Patients and Methods

A prospective cohort study was conducted. Patients were recruited into three age groups: less than 65 years (n = 65), 65 to 74 years (n = 68), and 75 years and older (n = 67). There were 200 patients enrolled in the study, of whom 115 were female and 85 were male, with a mean age of 69.9 years (sd 9.5, 42 to 92). They were assessed preoperatively, and at three, 12 and, 24 months postoperatively. Stem migration was assessed using Einzel-Bild-Röntgen-Analyse (EBRA). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), Hip Disability and Osteoarthritis Outcome Score (HOOS), EuroQol-5 domains questionnaire (EQ-5D), short form-36 questionnaire (SF-36,) and patient satisfaction were used to assess outcome. The Lower Extremity Activity Scale (LEAS), Timed Up and Go (TUG) test, and activPAL monitor (energy expelled, time lying/standing/walking and step count) were used to assess activity. The BMD was assessed in Gruen and Charnley zones.

Results

Mean varus/valgus tilt was -0.77⁰ and axial subsidence was -1.20 mm. No significant difference was observed between age groups (p ⩾ 0.07). There was no difference according to age group for postoperative WOMAC (p ⩾ 0.11), HHS (p ⩾ 0.06), HOOS (p ⩾ 0.46), EQ-5D (p ⩾ 0.38), patient satisfaction (p ⩾ 0.05), or activPAL (p ⩾ 0.06). Patients 75 years and older had a worse SF-36 physical function (p = 0.01) and physical role (p = 0.03), LEAS score (p < 0.001), a shorter TUG (p = 0.01), and a lower BMD in Charnley zone 1 (p = 0.02).

Conclusion

Exeter stem migration is within normal limits and is not influenced by age group. Functional outcome, patient satisfaction, activity level, and periprosthetic BMD are similar across all age groups.

Cite this article: N. D. Clement, M. Bardgett, K. Merrie, S. Furtado, R. Bowman, D. J. Langton, D. J. Deehan, J. Holland. Cemented Exeter total hip arthroplasty with a 32 mm head on highly crosslinked polyethylene: Does age influence functional outcome, satisfaction, activity, stem migration, and periprosthetic bone mineral density? Bone Joint Res 2019;8:275–287. DOI: 10.1302/2046-3758.86.BJR-2018-0300.R1.

Laser Surface Texturing of Alumina/Zirconia Composite Ceramics for Potential Use in Hip Joint Prosthesis

The use of metal shell to fix an acetabular cup to bone in hip joint prosthesis carries some limitations, including restrictions in prosthetic femur ball diameter and in patient’s range of motion. These drawbacks could be ideally overcome by using a monolithic ceramic acetabular cup, but the fixation of such an implant to host bone still remains a challenge. Since porous surfaces are known to promote more bone tissue interlocking compared to smooth materials, in this work the surfaces of sintered alumina/zirconia composite ceramics were treated by a pulsed laser radiation at 1064 nm with a pulse width in the nanosecond range, in order to impart controlled textural patterns. The influence of laser process parameters (e.g., energy per pulse, repetition rate, scanning speed, repetition number, angle of laser beam, and number of cycles) on the roughness and texture orientation was systematically investigated. The obtained surface topographies were inspected by optical and scanning electron microscopy, and the roughness was assessed by contact profilometry. Surface roughness could be modulated in the range of 3 to 30 µm by varying the processing parameters, among which the number of cycles was shown to play a major role. The laser treatment was also successfully adapted and applied to ceramic acetabular cups with a curved profile, thus demonstrating the feasibility of the proposed approach to process real prosthetic components.

Predicting the polyethylene wear rate in pin-on-disc experiments in the context of prosthetic hip implants: deriving a data-driven model using machine learning methods

Pin-on-disc (PoD) experiments are widely used to quantify and rank wear of different material couples for prosthetic hip implant bearings. However, polyethylene wear results obtained from different PoD experiments are sometimes difficult to compare, which potentially leaves information inaccessible. We use machine learning methods to implement several data-driven models, and subsequently validate them by quantifying the prediction error with respect to published experimental data. A data-driven model can supplement results from PoD wear experiments, and enables predicting polyethylene wear of new PoD experiments based on its operating parameters. It also reveals the relative contribution of individual PoD operating parameters to the resulting polyethylene wear, thus informing design of experiments, and potentially reducing the need for time consuming PoD wear measurements.

Choice of Prosthetic Implant Combinations in Total Hip Replacement: Cost-Effectiveness Analysis Using UK and Swedish Hip Joint Registries Data

BACKGROUND

Prosthetic implants used in total hip replacements (THR) have a range of bearing surface combinations (metal-on-polyethylene, ceramic-on-polyethylene, ceramic-on-ceramic, and metal-on-metal), head sizes (small [<36 mm in diameter] and large [≥36 mm in diameter]), and fixation techniques (cemented, uncemented, hybrid, and reverse hybrid). These can influence prosthesis survival, patients' quality of life, and healthcare costs.

OBJECTIVES

To compare the lifetime cost-effectiveness of implants for patients of different age and sex profiles.

METHODS

We developed a Markov model to compare the cost-effectiveness of various implants against small-head cemented metal-on-polyethylene implants. The probability that patients required 1 or more revision surgeries was estimated from analyses of more than 1 million patients in the UK and Swedish hip joint registries, for men and women younger than 55, 55 to 64, 65 to 74, 75 to 84, and 85 years and older. Implant and healthcare costs were estimated from local procurement prices, national tariffs, and the literature. Quality-adjusted life-years were calculated using published utility estimates for patients undergoing THR in the United Kingdom.

RESULTS

Small-head cemented metal-on-polyethylene implants were the most cost-effective for men and women older than 65 years. These findings were robust to sensitivity analyses. Small-head cemented ceramic-on-polyethylene implants were most cost-effective in men and women younger than 65 years, but these results were more uncertain.

CONCLUSIONS

The older the patient group, the more likely that the cheapest implants, small-head cemented metal-on-polyethylene implants, were cost-effective. We found no evidence that uncemented, hybrid, or reverse hybrid implants were the most cost-effective option for any patient group. Our findings can influence clinical practice and procurement decisions for healthcare payers worldwide.

Nano-sized Al2O3 particle-induced autophagy reduces osteolysis in aseptic loosening of total hip arthroplasty by negative feedback regulation of RANKL expression in fibroblasts

Aseptic loosening is mainly caused by wear debris generated by friction that can increase the expression of receptor activation of nuclear factor (NF)-κB (RANKL). RANKL has been shown to support the differentiation and maturation of osteoclasts. Although autophagy is a key metabolic pathway for maintaining the metabolic homeostasis of cells, no study has determined whether autophagy induced by Al₂O₃ particles is involved in the pathogenesis of aseptic loosening. The aim of this study was to evaluate RANKL levels in patients experiencing aseptic loosening after total hip arthroplasty (THA) and hip osteoarthritis (hOA) and to consequently clarify the relationship between RANKL and LC3II expression. We determined the levels of RANKL and autophagy in fibroblasts treated with Al₂O₃ particles in vitro while using shBECN-1 interference lentivirus vectors to block the autophagy pathway and BECN-1 overexpression lentivirus vectors to promote autophagy. We established a novel rat model of femoral head replacement and analyzed the effects of Al₂O₃ particles on autophagy levels and RANKL expression in synovial tissues in vivo. The RANKL levels in the revision total hip arthroplasty (rTHA) group were higher than those in the hOA group. In patients with rTHA with a ceramic interface, LC3II expression was high, whereas RANKL expression was low. The in vitro results showed that Al₂O₃ particles promoted fibroblast autophagy in a time- and dose-dependent manner and that RANKL expression was negatively correlated with autophagy. The in vivo results further confirmed these findings. Al₂O₃ particles induced fibroblast autophagy, which reduced RANKL expression. Decreasing the autophagy level promoted osteolysis and aseptic prosthetic loosening, whereas increasing the autophagy level reversed this trend.

Gene expression in adverse reaction to metal debris around metal-on-metal arthroplasty: An RNA-Seq-based study

Joint replacement surgery is a standard treatment of advanced osteoarthritis (OA). Since 2000, cobalt-chromium (CoCr) metal-on-metal (MoM) implants were widely used in hip arthroplasties. Some patients developed "adverse reaction to metal debris" (ARMD) around the prosthesis, resulting in a need for revision surgery. In the present study, we addressed the pathogenesis of ARMD by genome-wide expression analysis. Pseudosynovial ARMD tissue was obtained from revision surgery of Articular Surface Replacement (ASR, DePuy, Warsaw, IN, USA) hip arthroplasties. Control tissue was 1) OA synovium from primary hip arthroplasties and 2) inflammatory pseudosynovial tissue from metal-on-plastic (MoP) implant revisions. In ARMD tissue, the expression of 1446 genes was significantly increased and that of 1881 decreased as compared to OA synovium. Genes associated with immune response, tissue development and certain leukocyte signaling pathways were enriched in the differently (FC > 2) expressed genes. The network analysis proposed PRKACB, CD2, CD52 and CD53 as the central regulators of the greatest (FC > 10) differences. When ARMD tissue was compared to MoP tissue, the expression of 16 genes was significantly higher and that of 21 lower. Many of these genes were associated with redox homeostasis, metal ion binding and transport, macrophage activation and apoptosis. Interestingly, genes central to myofibroblast (AEBP1 and DES) and osteoclast (CCL21, TREM2 and CKB) development were upregulated in the MoP tissue. In network analysis, IL8, NQO1, GSTT1 and HMOX1 were identified as potential central regulators of the changes. In conclusion, excessive amounts of CoCr debris produced by MoM hip implants induces in a group of patients a unique adverse reaction characterized with enhanced expression of genes associated with inflammation, redox homeostasis, metal ion binding and transport, macrophage activation and apoptosis.