Bearing Surface Combinations Research Articles

A unique tribological inverted bearing solution for reverse shoulder arthroplasty: Vitamin E and ceramic (unique inverse pairings in rTSR).

Reverse total shoulder arthroplasty has gained popularity for various shoulder conditions and has evolved over time to accommodate for material changes and design philosophy including inverse materials. The tribological behaviour of shoulder arthroplasty has been extensively studied in relation to biological osteolysis which is a notable concern regarding component loosening. This study aims to assess the wear performance of a vitamin E-stabilised glenosphere or conventional ultra-high-molecular-weight polyethylene glenosphere whilst paired with ceramic or cobalt-chrome-molybdenum inlay in a shoulder joint wear simulator. A cumulative total of five million cycles was utilised with gravimetric and visual analysis of wear. Gravimetric wear was observed to be the lowest when a vitamin E-stabilised glenosphere was paired with a ceramic inlay - demonstrating the greatest wear resistance. Our results demonstrate that the combination of vitamin E-stabilised polyethylene glenosphere and ceramic inlay has improved wear resistance properties in load simulations when compared to other bearing surface combinations. This supports the use of the novel inverse combination in clinical practice to attain longer-term survivorship in reverse total shoulder replacements. Basic Science Study; Tribology.

Role of femoral head material on readmission and mortality rates following elective primary total hip arthroplasty in Medicare patients.

The role of different femoral head materials for total hip arthroplasty (THA) has been widely studied in the context of wear properties and corrosion. Cobalt chrome (CoCr) femoral heads are commonly used as a standard of comparison to other materials such as ceramic and oxidized zirconium (OxZi). This study aims to evaluate the impact of femoral head material on clinical outcomes in elective primary THA patients. Retrospective analysis of THA patients within the Medicare claims database between October 2017 and September 2020 using diagnosis-related group codes was conducted. Information collected included sex, age, Charlson Comorbidity Index, and femoral head type. Patients with CoCr femoral heads were compared against patients with either OxZi or ceramic femoral heads using 1:1 propensity score matching. Z-testing and Chi-square analysis were used to determine between-group significance. In total, 112,960 elective THA patients were included, with 56,480 in OxZi or ceramic and 56,480 in CoCr. Readmission rates were lower in patients that received OxZi or ceramic femoral heads at 30-day (p < 0.0001), 60-day (p < 0.0001), and 90-day postoperatively (p < 0.0001) compared to CoCr. Mortality rates were also lower in patients that received OxZi or ceramic femoral heads at 30-day (p = 0.004), 60-day (p = 0.018), and 90-day postoperatively (p = 0.009) compared to CoCr. CoCr femoral heads had higher rates of readmissions and mortality compared to OxZi or ceramic. Further analysis of bearing surface combinations and sub-group analyses to determine significance between-group differences is needed. Retrospective analysis.

Best option for total hip replacement in young: evidence from National Joint Registry of United Kingdom and Australian Orthopaedic Association National Joint replacement Registry

Introduction&#x0D; &#x0D; Implant longevity is crucial in determining the clinical success of THA. Hence THA in young patients will need a careful consideration as the failure and revision rates of THA are higher due to high functional demands. &#x0D; &#x0D; Method&#x0D; &#x0D; Reviewed the latest evidence from the 17th annual report of National Joint Registry (NJR) of United Kingdom and the 2020 annual report of Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to determine the optimal mode of fixation, bearing surface and the head size for THA in a patient before the age of 55 years.&#x0D; &#x0D; Results &#x0D; &#x0D; In THA of patients under 55 Years, the 10 Year RR was highest in Uncemented fixations compared to other modes but this difference is insignificant according to the AOANJRR. Uncemented and hybrid fixations were preferred over cemented fixations but uncemented was clearly the predominant mode of fixation and this preference was rising over the past years. COC and COP bearing surface combinations reported to have the lowest 10 YRR and the use of COP in young patients has been rising both in UK and Australia in the recent past. In COC the head size of 40mm showed the best survival rate and in COP 36mm was the largest size with better survival. In COP the increased quality with XLPE (ultra-high molecular weight polyethylene) has been the reason for the ability use a larger head size with low dislocation rates better survival with low wear compared to Non XLPE used in the past. &#x0D; &#x0D; Conclusion&#x0D; &#x0D; Both Registries favour the use of Uncemented or Hybrid fixations with COC and COP bearings in patients

11 Understanding the Clinical Performance of Ceramic Coated Femoral Components in Knee Arthroplasty Surgery

Abstract Aim In vitro knee simulation has demonstrated favourable wear properties and decreased metal ion release of ceramic coated metal femoral components in total knee arthroplasty surgery. Femoral implants coated with ceramic have been used in patients, however the subsequent clinical performance and time-to-revision of these implants is largely unknown. The scope of this study was to review the current available clinical literature, focusing on retrieval studies of Ceramic-Coated TKAs. Method Literature review of PubMed and MEDLINE. All studies included demonstrated clinical evaluation of implant performance, either in vivo or at revision. Results 9 studies were identified and included for analysis in this study. Retrieval analysis has illustrated microscopic defects in coatings of revised implants, with associated abrasion and 3rd body wear of the polyethylene component. Evidence suggests that coating femoral components with ceramic can prevent effective cement bonding, leading to aseptic loosening and thus earlier implant failure. Despite these problems, high volume centres have been able to demonstrate comparable results when compared with traditional bearing surface combinations. The mechanism behind metal ion hypersensitivity is currently poorly understood; however, the use of ceramic coated knee replacements is demonstrating a reduction in metal ion release. Conclusions Whilst conferring favourable clinical properties in certain instances, the lack of surgical, implant and patient data surrounding the use of this coated implants remains concerning. The literature base remains limited, and meaningful clinical conclusions cannot be drawn. Recommendations include performing robust clinical trials in order to delineate the clinical efficacy of ceramic coatings in knee arthroplasty.

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

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

Conventional Polyethylene in Total Hip Arthroplasty in Young Patients: Survivorship, Wear Analysis, and Clinical Outcomes Between 15 and 20 Years

BackgroundTotal hip arthroplasty (THA) remains a successful procedure for most patients. However, there is a paucity of information regarding the long-term performance of conventional polyethylene (CPE) bearings in young patients undergoing THA. MethodsAfter accounting for incomplete follow-up of a prospective cohort of 123 THAs in patients ≤50 years, we performed a retrospective review of 101 hips in 84 patients (82.1%) with an average 17.1-year follow-up (14.7-19.6 years). Outcomes of interest included linear and volumetric wear, clinical outcome scores, implant survivorship, and patient mortality. Wear rates were calculated using Martell Software. ResultsWear analysis revealed median linear and volumetric wear rates of 0.106 mm/y (confidence interval, 0.079-0.133) and 43.58 mm3/y (confidence interval, 33.4-53.75). The modified Harris hip scores improved by 36 points while University of California, Los Angeles activity scores improved by 2.0 points at 15-year follow-up (P < .0001). Twenty-two hips (21.8%) were revised, 13 of which (12.8%) were for wear-related causes at an average of 14.9 years (range, 9.2-21 years) from index arthroplasty. There was significantly higher mortality in patients with a preoperative diagnosis of inflammatory avascular necrosis (P = .015). ConclusionBecause CPE was commonly used in THA over the last 25 years, it is important to understand its implications on the growing revision burden. Significant concerns exist with regard to the long-term durability of CPE bearings in young, moderately active patients 15 years after THA. These patients should be followed closely for wear-related problems. Our results should be used as a comparison when evaluating the outcomes of more modern bearing surface combinations.

Which is the best bearing surface for primary total hip replacement? A New Zealand Joint Registry study.

We have investigated the revision rates of all bearing surface combinations for primary total hip replacement (THR) registered on the New Zealand Joint Registry (NZJR) to determine which coupling has been the most durable and successful over the last 16 years. There were 106,139 primary THRs registered, resulting in 4,960 revisions for any cause. We examined all-cause revision rates, reasons for revision and performed survival analyses. Ceramic-on-highly cross-linked polyethylene (CoPx) had the lowest all-cause revision rate of 0.54/100-component-years (cys) (95% confidence interval 0.48 to 0.61). This was superior to all other hard-on-soft bearing combinations in unadjusted analysis. Furthermore, the age of patients receiving CoPx was significantly lower than for metal-on-polyethylene (mean 62.9; standard deviation [SD] 10.1 vs. 69.1; SD 9.6; p<0.001). Acetabular loosening was the reason for revision in 14.5% of CoPx, compared to 33% of MoP THRs (p<0.001). Metal-on-metal bearings had the highest revision rate of 1.43/100 cys and were significantly inferior to CoPx (p<0.001). Kaplan-Meier analysis and Cox regression analyses were performed and we adjusted the analyses to control for age, femoral head size, surgical approach and fixation. CoPx remained the most durable and successful coupling used in primary THR in New Zealand irrespective of age, gender or size of femoral head.

The choice between hip prosthetic bearing surfaces in total hip replacement: a protocol for a systematic review and network meta-analysis.

BackgroundProsthetic hip implants have many combinations of bearing surface materials, sizes, and fixation techniques, which can determine the quality of life of patients after primary total hip replacement (THR) and the likelihood of needing revision surgery. When an implant fails, patients require revision THR, which is distressing to the patient and expensive for the health care payer. Primary THR is one of the most common elective procedures performed worldwide, with over 300,000 performed annually in the USA and over 80,000 in England and Wales. It is important to review all available randomised controlled trial (RCT) evidence to determine which implant bearing surface materials, size, and fixation technique are most effective for patients.Methods/DesignThis is a protocol for a systematic review and meta-analysis of RCTs comparing outcomes of hip implant bearing surfaces, size, and fixation techniques used in THR. Implant combinations compared in the literature include four bearing surface combinations (metal-on-polyethylene, metal-on-metal, ceramic-on-polyethylene, and ceramic-on-ceramic); two femoral head sizes (large vs small heads); and four fixation techniques (uncemented, cemented, hybrid, and reverse hybrids). The primary outcome will be revision surgery. We will also collect data on patient characteristics, mortality, quality of life, and other outcomes. In network meta-analysis, we will estimate the relative effectiveness of every implant bearing surface, head size (large vs small), and fixation permutation, using evidence where implants have been compared directly in an RCT and indirectly through common comparators in different RCTs.DiscussionThere has been much debate about materials used for prosthetic implants in THR. Different combinations of prosthetic materials, sizes, and fixation, can vary widely in cost and fail at different rates for different patient groups. Given the number of THRs performed yearly, and the increasing use of expensive implants, it is important to review evidence to inform surgeons, patients, and health care providers of optimal implant bearing combinations for given patient characteristics. This review will inform a cost-effectiveness model that will include evidence from other sources, to determine the most effective and cost-effective implant bearing combination for patients.Systematic review registrationPROSPERO CRD42015019435

PMS51 - What Is The Cost-Effective Bearing Surface Choice In Primary Total Hip Arthroplasty

The primary bearing surface combination since the advent of total hip arthroplasty (THA) in the 1960s has been a metal femoral head with a polyethylene acetabular cup (MoP). Design efforts to improve THA implant life have focused on ceramic-on-ceramic (CoC) and metal-onmetal (MoM) bearings. As these surfaces permeated the market, significant clinical problems were seen with each. This is leading to a market shift toward ceramic-on-polyethylene (CoP) bearings, based on laboratory and in vivo wear studies that predict longer useful life in patient populations. The primary clinical measurement of THA success is the long-term replacement (revision) rate of the original hip implant. Sufficient information on the key parameter, long term revision rate, is just beginning to be available.

The current state of bearing surfaces in total hip replacement

We reviewed the literature on the currently available choices of bearing surface in total hip replacement (THR). We present a detailed description of the properties of articulating surfaces review the understanding of the advantages and disadvantages of existing bearing couples. Recent technological developments in the field of polyethylene and ceramics have altered the risk of fracture and the rate of wear, although the use of metal-on-metal bearings has largely fallen out of favour, owing to concerns about reactions to metal debris. As expected, all bearing surface combinations have advantages and disadvantages. A patient-based approach is recommended, balancing the risks of different options against an individual's functional demands.

Acoustic Emission Monitoring of Total Hip Arthroplasty Implants

Acoustic Emission (AE) monitoring of patients with Total Joint Replacement (TJR) implants uses an array of four passive ultrasonic receivers to undertake in-vivo monitoring of the acoustic events created by patients with TJR implants. This manuscript presents and compares the results of in-vivo and in-vitro measurements of the acoustic signature created by a range of Total Hip Replacement (THR) implants. A major focus of this investigation is in the characterization of squeaking of hard-on-hard bearing surface combinations. The presence of an audible squeak of the bearing surface can cause significant embarrassment and potential discomfort to patients. It has been identified that squeaking is primarily identified at the main bearing interface and the fundamental peak falls in the range of 2-5kHz, with multiple higher harmonics also observed. The frequency of the primary squeak is seen to vary based on bearing surface type of both the acetabular liner and femoral head (ceramic-on-ceramic, metal-on- metal bearing combinations)Comparison is also drawn between in-vivo and in-vitro testing through the use of implant components retrieved during revision surgery of patients previously subjected to in-vivo testing. In the trials presented within this manuscript, strong correlation was achieved between the two test methods. In-vivo signal magnitudes were substantially smaller than those recorded from bench tests directly on the implant. However, characteristic frequencies were very similar in both cases, indicating that tissue attenuation reduces signal magnitude, but the influence of any period shifting of signals through the soft tissue were minimal. These initial results provide an important base for future testing and provide useful insight into the underlying cause of audible squeaking of total hip replacement patients with hard-on-hard bearing surfaces.

Modern Metal-on-Metal Hip Implants

This Technology Overview was prepared using systematic review methodology and summarizes the findings of studies published as of July 15, 2011, on modern metal-on-metal hip implants. Analyses conducted on outcomes by two joint registries indicate that patients who receive metal-on-metal total hip arthroplasty (THA) and hip resurfacing are at greater risk for revision than are patients who receive THA using a different bearing surface combination. Data from these registries also indicate that larger femoral head components have higher revision rates and risk of revision and that older age is associated with increased revision risks of large-head metal-on-metal THA. Several studies noted a correlation between suboptimal hip implant positioning and higher wear rates, local metal debris release, and consequent local tissue reactions to metal debris. In addition, several studies reported elevated serum metal ion concentrations in patients with metal-on-metal hip articulations, although the clinical significance of these elevated ion concentrations remains unknown.

The Utility of MARS MRI in Patients with Metal-on-Metal Bearings

Metal-on-metal bearings for total hip arthroplasty have a long history of use that dates back to the introduction of the McKee-Farrar prosthesis in the 1960s. Metal-on-metal bearings ultimately fell out of favor because of the excellent clinical results of the Charnley low-friction arthroplasty concept, which employed metal-on-UHMWPE (ultra-high molecular weight polyethylene) bearing surfaces. However, the use of metal-on-metal bearings was revisited in the 1990s as polyethylene-associated periprosthetic osteolysis emerged as a major clinical problem limiting the longevity of hip reconstructions in high-demand patient populations. Within the last decade, numerous metal-on-metal designs for both total hip arthroplasty and hip resurfacing arthroplasty have been introduced into the marketplace. However, over the last several years it has become evident that contemporary metal-on-metal bearings are not immune to some of the problems, including periprosthetic osteolysis, that have plagued other bearing surface combinations. In addition, investigators described a distinct histological pattern, termed “aseptic lymphocyte-dominated vasculitis-associated lesion” (ALVAL), that was associated with symptomatic metal-on-metal bearings. More recently, investigators described local soft-tissue reactions termed “pseudotumors” in association with symptomatic metal-on-metal devices. Initially, studies of adverse local tissue reactions (including osteolysis, ALVAL, and pseudotumors) in retrospective studies of metal-on-metal implants did not indicate the prevalence. However, case-control studies and registries began to document that certain metal-on-metal bearing designs were associated with an unacceptably high failure rate, leading to high-profile device recalls that captured the attention of the worldwide media. In some cases, the adverse local tissue response …

A frictional study of total hip joint replacements

Polymeric wear debris produced by articulation of the femoral head againstthe ultra-high-molecular-weight polyethylene socket of a total hipreplacement has been implicated as the main cause of osteolysis andsubsequent failure of these implants. Potential solutions to this problemare to employ hard bearing surface combinations such as metal-on-metal orceramic-on-ceramic prostheses. The aim of this study was to investigate thedifference in lubrication modes and friction of a range of materialcombinations using synthetic and biological fluids as the lubricants. Theexperimental results were compared with theoretical predictions of filmthicknesses and lubrication modes. A strong correlation was observedbetween experiment and theory when employing carboxy methyl cellulose (CMC)fluids as the lubricant. Under these conditions the ceramic-on-ceramicjoints showed full fluid film lubrication while the metal-on-metal,metal-on-plastic, diamond-like carbon-coated stainless steel(DLC)-on-plastic and ceramic-on-plastic prostheses operated under a mixedlubrication regime. With bovine serum as the lubricant in the all ceramicjoints, however, the full fluid film lubrication was inhibited due toadsorbed proteins. In the metal-on-metal joints this adsorbed protein layeracted to reduce the friction while in the ceramic coupling the friction wasincreased. The use of bovine serum as the lubricant also significantlyincreased the friction in both the metal-on-plastic and ceramic-on-plasticjoints. The friction produced by the DLC-on-plastic joints depended on thequality of the coating. Those joints with a less consistent coating andtherefore a higher surface roughness gave significantly higher frictionthan the smoother, more consistently coated heads.

Cementless Total Joint Arthroplasty Prostheses With Titanium-Alloy Articular Surfaces

Surgical implants of titanium alloy (Ti-6Al-4V) have been found to be susceptible to abrasive wear, resulting in the well-known phenomenon of metallosis. In the presence of the acrylic debris generated by loose joint arthroplasty prostheses, this abrasive wear is greatly increased. However, the bone loss seen in these cases has generally been presumed to be due to the osteolytic effects of particulate acrylic, not the alloy debris, which has generally been assumed to be biocompatible. To examine the in vivo effects of titanium-alloy wear without the added presence of acrylic debris, a comprehensive analysis was made of cementless human joint arthroplasty prostheses with Ti-6Al-4V alloy surfaces articulating on ultra-high molecular weight polyethylene (UHMWPE). Specimens, including the prostheses, synovium, pseudocapsule and additional soft tissues, and periarticular bone, were retrieved from 22 hips and two knees. Specimens were examined by histologic techniques, energy-dispersive X-ray analysis, and electron microscopy. Serial sections of the implants were evaluated for tissue ingrowth. Tissues surrounding all joints implanted more than one year showed some degree of discoloration indicative of metallosis, whereas after two years the synovium was hypertrophic and villiform. Histologic evaluation showed good fixation by bony ingrowth in the vast majority of cases, although location and extent of ingrowth was dependent on numerous factors. Viability of ingrowth bone was established by fluorochrome labeling. However, despite good biologic fixation, cavitary osteolysis of the bone surrounding the implants was frequently identified. These lesions were filled with sheets of aggressive macrophages within a matrix of fibrous tissue and necrotic debris. Under polarized light the macrophages were found to be filled with alloy and polyethylene fragments of a characteristic size. Osteoblast-mediated remodeling of bone was infrequently observed. Instead, the bone was resorbed along a front in contact with the granulomatous tissues filling the cystic lesions. Visible burnishing was observed on every articular surface, with a linear relationship between wear and time implanted. By one year the surfaces were covered with a characteristic "scratch and gouge" pattern, similar on all sizes of femoral heads as well as the total knee prostheses. This study demonstrates that the combination of Ti-6Al-4V alloy and UHMWPE, when used as a bearing surface combination in total joint arthroplasty prostheses, results in excessive wear of both metal and polymer.(ABSTRACT TRUNCATED AT 400 WORDS)