Association of Total Hip Arthroplasty Flexural Rigidity With Magnetic Resonance Imaging and Histological Findings.

Background: Modular connections in total hip arthroplasty (THA) offer surgical advantages, but can contribute to implant fretting and corrosion due to micromotion at the head-stem interface. Previous studies implicated lower flexural rigidity as a key contributing factor to THA corrosion and fretting, but none associated flexural rigidity with direct histological evaluation or magnetic resonance imaging (MRI) outcomes. The purpose of this study was to determine how implant flexural rigidity is associated with MRI imaging metrics and histopathological outcomes in patients who have a failed THA.

Cause for concern? Significant cement coverage in retrieved metaphyseal cones after revision total knee arthroplasty.

Background: Metaphyseal cones are used to manage bone loss in revision total knee arthroplasty with increasing popularity. Post-operative radiographs and explant procedures suggest that cement may extrude around the cone implant into the cone-bone interface and prevent biologic in- or on-growth. The purpose of this study was to perform a retrieval analysis to describe the pattern of direct cementation onto the porous surface area of metaphyseal cones.

Patellofemoral arthroplasty conversion to total knee arthroplasty: An updated retrieval analysis and clinical outcomes.

Background: A prior retrieval analysis found high rates of infection after conversion of PFA to TKA, but was limited by a small sample size. The purpose of this study is to perform a retrieval analysis with clinical correlation on an expanded group of patients to better understand conversion of PFA to TKA.

Method: A retrospective review of an implant retrieval registry identified 62 conversions of PFA to TKA between 2004-2021.

Narrative Review: Is There a Transfusion Cutoff Value After Which Nonsurvivability Is Inevitable in Trauma Patients Receiving Ultramassive Transfusion?

The institution of massive transfusion protocols (MTPs) has improved the timely delivery of large quantities of blood products and improves patient outcomes. In recent years, the cost of blood products has increased, compounded by significant blood product shortages. There is practical need for identification of a transfusion volume in trauma patients that is associated with increased mortality, or a threshold after which additional transfusion is futile and associated with nonsurvivability.

Delayed Failure of M6-C Cervical Disc Arthroplasty After Conversion of Adjacent Cervical Disc Arthroplasty to Fusion: A Case Report.

Case: We present a delayed failure of an M6-C cervical disc arthroplasty after conversion of a subjacent failed cervical disc arthroplasty to fusion. The annular component had failed, and the core had been ejected. Histology demonstrated a giant cell reaction to polyethylene debris, and tissue cultures were positive for Cutibacterium acnes.

Slug Flow Coprecipitation Synthesis of Uniformly-Sized Oxalate Precursor Microparticles for Improved Reproducibility and Tap Density of Li(NiCoMn)O Cathode Materials.

The microparticle quality and reproducibility of Li(NiCoMn)O (NCM811) cathode materials are important for Li-ion battery performance but can be challenging to control directly from synthesis. Here, a scalable reproducible synthesis process is designed based on slug flow to rapidly generate uniform micron-size spherical-shape NCM oxalate precursor microparticles at 25-34 °C. The whole process takes only 10 min, from solution mixing to precursor microparticle generation, without needing aging that typically takes hours.

NEREL-BIO: a dataset of biomedical abstracts annotated with nested named entities.

Motivation: This article describes NEREL-BIO-an annotation scheme and corpus of PubMed abstracts in Russian and smaller number of abstracts in English. NEREL-BIO extends the general domain dataset NEREL by introducing domain-specific entity types. NEREL-BIO annotation scheme covers both general and biomedical domains making it suitable for domain transfer experiments.

Polyethylene Dual Mobility Liners Show Minimal Polyethylene Changes in Early Retrievals.

Background: Dual mobility (DM) liners were introduced to reduce instability in total hip arthroplasty. They were found to allow for motion predominantly at the femoral head and the inner bearing of the acetabular liner; however, little is known if this motion is sufficient to alter polyethylene material characteristics. We assessed cross-link (XL) density and oxidation index (OI) measurements of the inner and outer bearing articulations.

Clinical and Biomechanical Characteristics of Posterior-Stabilized Polyethylene Post Fractures in Total Knee Arthroplasty: A Retrieval Analysis.

Background: Fractures of the polyethylene post are a rare but known complication after posterior-stabilized (PS) total knee arthroplasty (TKA). We evaluated the polyethylene and patient characteristics for 33 primary PS polyethylene components that were revised with fractured posts.

Methods: We identified 33 PS inserts revised between 2015 and 2022.

Scalable Advanced Li(NiCoMn)O Cathode Materials from a Slug Flow Continuous Process.

Li[NiCoMn]O (LNCMO811) is the most studied cathode material for next-generation lithium-ion batteries with high energy density. However, available synthesis methods are time-consuming and complex, restricting their mass production. A scalable manufacturing process for producing NCM811 hydroxide precursors is vital for commercialization of the material.

Tribocorrosion is common but mild in modular humeral components in shoulder arthroplasty: an implant retrieval analysis.

Background: Wear and corrosion at the junctions of modular implants are increasingly recognized issues in the design of hip and knee arthroplasty prostheses, yet less is known about their significance in shoulder arthroplasty.

Methods: A query of paired total shoulder implant specimens (eg, humeral head and stem components from the same patient) was performed using an institutional implant retrieval registry. Implants were examined under a stereomicroscope and evaluated for evidence of fretting and corrosion using the modified Goldberg scoring system.

Magnetic Resonance Imaging Synovial Classification Is Associated With Revision Indication and Polyethylene Insert Damage.

Background: Patients with total knee arthroplasty (TKA) stiffness are commonly presumed to have arthrofibrosis though no specific test exists. In patients undergoing revision TKA, we asked the following question: (1) Do patients who are revised for stiffness display a synovial reaction on MRI that is different than patients revised for other reasons? (2) Do these patients have a different magnitude of polyethylene insert damage than patients revised for other reasons? and (3) Is the MRI synovial classification associated with polyethylene insert damage?

Methods: Patients undergoing revision TKA for stiffness had a preoperative MRI performed, and the synovium was classified on MRI in a blinded fashion as arthrofibrosis, focal scarring, polymeric reaction, infection, or abnormal. At surgery, the polyethylene inserts were removed, and graded by 2 reviewers for total surface damage.

A Postmortem Analysis of Polyethylene Damage and Periprosthetic Tissue in Rotating Platform and Fixed Bearing Tibial Inserts.

Background: Mobile bearing designs are intended to reduce wear, but mixed results were reported from retrieval analyses. Postmortem evaluation (PM) provides the opportunity to assess polyethylene damage in successful implants. We compared damage patterns, MRI presentation, and histology between mobile-bearing and fixed tibial inserts retrieved postmortem and compared these results to our prior findings from implants retrieved at revision.

Unexpected Wear of a Uniquely Designed Moderately Cross-Linked Polyethylene in Total Hip Arthroplasty.

Background: A uniquely designed, non-heat-treated moderately cross-linked acetabular polyethylene liner used in total hip arthroplasty (THA) demonstrated excessive wear during routine follow-up, prompting an evaluation of the linear wear rate.

Methods: All THAs were performed by the senior author. The study group included 38 THAs using the uniquely designed polyethylene in question, compared to a control group of 21 THAs using another moderately cross-linked polyethylene with good 10-year outcomes.

Bone Ongrowth of Contemporary Cementless Tibial Components: A Retrieval Analysis.

Background: Cementless total knee arthroplasty is gaining interest as total knee arthroplasty patients become younger, more active, and interested in long-term biologic fixation. New porous coatings have altered mechanical properties to improve bone osseointegration, although limited data exist on this topic. We measured the bone ongrowth on retrieved tibial trays to determine how demographic, radiographic, or implant design factors correlate with ongrowth.

Adaptive Immune Response Associated with a Zirconium-Containing, Cemented, Total Knee Arthroplasty: A Case Report.

Case: A 69-year-old woman underwent revision total knee arthroplasty for patellar component aseptic loosening. The periprosthetic tissue demonstrated histologic features of an adaptive immune response (aseptic lymphocyte-dominant vasculitis-associated lesion [ALVAL]). No particles of corrosion debris were identified.

Chemical Upcycling of Waste Poly(bisphenol A carbonate) to 1,4,2-Dioxazol-5-ones and One-Pot C-H Amidation.

Chemical upcycling of poly(bisphenol A carbonate) (PC) was achieved in this study with hydroxamic acid nucleophiles, giving rise to synthetically valuable 1,4,2-dioxazol-5-ones and bisphenol A. Using 1,5,7-triazabicyclo[4.4.

Retrieval Analysis of Polyethylene Components in Rotating Hinge Knee Arthroplasty Implants.

Background: This study examined a cohort of retrieved rotating hinge (RH) total knee arthroplasty implants of four different designs with emphasis on the surface damage observed on the polyethylene components. Our purpose was to determine if differences in polyethylene damage existed among the designs, and if those differences could be explained by differences in design characteristics.

Materials And Methods: Seventy-two RH implants from four manufacturers (DePuy LPS/SROM, Zimmer NexGen, Stryker Howmedica MRH, and Biomet Finn-OSS) removed at the time of revision performed between 2002 and 2017 were identified in our institutional retrieval registry.

Porous Coatings in Retrieved Acetabular Components.

Background: We evaluated bone volume fraction in retrieved acetabular shells with 2 types of porous coatings: (1) titanium fiber mesh (HG) components and (2) tantalum metal coating (TM) components.

Methods: Eight HG shells were matched to 8 TM shells for patient age, body mass index, and gender. The mean age at index surgery was 69 (51-82) years, mean body mass index was 28 (21-40), and patients were evenly divided between male and female (4:4).

Bio-sorbents, industrially important chemicals and novel materials from citrus processing waste as a sustainable and renewable bioresource: A review.

Citrus waste includes peels, pulp and membrane residue and seeds, constituting approximately 40-60% of the whole fruit. This amount exceeds ~110-120 million tons annually worldwide. Recent investigations have been focused on developing newer techniques to explore various applications of the chemicals obtained from the citrus wastes.

Complete wear-through of a metal-backed acetabular cup in an ambulatory patient.

We present a rare case of a patient who presented with complete and rapid wear-through of a ceramic femoral head through a polyethylene liner and titanium acetabular cup. In addition, this patient exhibited significantly elevated serum titanium ion levels, which may serve as a marker of severe metallosis in cases where the preoperative plain radiographs underestimate signs of periarticular metal debris. The unique findings of this case include the rapid (less than 1 year time) wear-through of the femoral head in interval radiographs and the dramatic progression of metallosis and pelvic and femoral osteolysis that required both component revision.

No Difference in Force Required for Intraprosthetic Dislocation of Mixed Manufacturer vs Same Manufacturer Dual Mobility Articulations.

Background: To avoid the morbidity of removing well-fixed implants during revision surgery, the off-label practice of mixing femoral heads with dual mobility (DM) polyethylene liners from different manufacturers is commonly performed. The resistance to intraprosthetic dislocation, when the inner prosthetic head disengages from the polyethylene bearing, between mixed and same manufacturer constructs remains unknown.

Methods: Between January 2010 and July 2018, 168 DM liners were retrieved.

Osteointegration in Compliant Self-Adjusting Compression Fixation Shown by Backscatter Electron Microscopy: A Case Report.

Compliant self-adjusting compression implants are a novel approach to increase the durability of megaprosthesis fixation. However, there is no report of current implant designs that documents the bone-prosthetic interface of this implant. A well-fixed compliant, self-adjusting distal femoral replacement was retrieved from a patient undergoing revision unrelated to fixation.

Modular junction fractures in a modern rotating-platform knee arthroplasty system.

In this series, we report the findings from four patients who presented with pain and mechanical symptoms after revision total knee arthroplasty with the DePuy Sigma TC3 RP prosthesis. Plain radiographs for each patient demonstrated failure of the femoral component at the modular junction of the femoral prosthesis. Retrieved implants at the time of surgery revealed fractures occurring exclusively at the femoral adapter bolt and the corresponding adapter.

Do oxidized zirconium heads decrease tribocorrosion in total hip arthroplasty? A study of retrieved components.

Aims: The aim of this study was to evaluate fretting and corrosion in retrieved oxidized zirconium (OxZr; OXINIUM, Smith & Nephew, Memphis, Tennessee) femoral heads and compare the results with those from a matched cohort of cobalt-chromium (CoCr) femoral heads.

Patients And Methods: A total of 28 OxZr femoral heads were retrieved during revision total hip arthroplasty (THA) and matched to 28 retrieved CoCr heads according to patient demographics. The mean age at index was 56 years (46 to 83) in the OxZr group and 70 years (46 to 92) in the CoCr group.