Different polymethylmethacrylate (PMMA) reinforcement strategies for long bone osteoplasty procedures: a controlled laboratory comparison using the 4-point bending test.

Background: Cementoplasty has been successfully used for treating fractures in various parts of the human body, although the use in weight-bearing long bones is a subject of controversial debate. Strategies to improve the mechanical properties of polymethylmethacrylate-based bone cement (BC) comprise changing the chemical composition or the application of metal reinforcement strategies. In clinical practice reinforced bone cement is used despite biomechanical basic research regarding this topic being scare.

Peri-implant femoral fractures in elderly: Morbidity, mortality, treatment options and good practices.

Purpose: Femur fractures are among the most common fractures treated surgically, representing a significant challenge for the orthopedic surgeon. Peri-implant femoral fractures (PIFFs) represent a rare complication of the surgical treatment. It is necessary to pay attention during osteosynthesis, evaluating not only the fracture site but the entire femoral skeletal structure, the characteristics of the fracture, the health comorbidities, and the risk of malunion and pseudarthrosis.

Chronic pelvic insufficiency fractures and their treatment.

Fragility and insufficiency fractures of the pelvis (FFP) and sacrum (SIF) are increasingly prevalent, particularly among the elderly, due to weakened bone structure and low-energy trauma. Chronic instability from these fractures causes persistent pain, limited mobility, and significant reductions in quality of life. Hospitalization is often required, with substantial risks of loss of independence (64-89%) and high mortality rates (13-27%).

Fracture strength and marginal and internal adaptation of lithium disilicate and hybrid ceramic endocrowns and non-retentive overlays for endodontically treated molar teeth.

Background: With the advances in the adhesive science, several conservative treatment options such as non-retentive overlays have been suggested for endodontically treated posterior teeth. However, information is scarce regarding the fracture strength and adaptation of non-retentive overlays compared with endocrowns, and the effect of material type in this respect. Thus, this study aimed to assess the fracture strength and internal and marginal adaptation of lithium disilicate (LDS) and hybrid ceramic endocrowns and non-retentive overlays for endodontically treated molar teeth.

Do Patient-Answered Versus Caregiver-Answered Patient-Reported Outcomes Differ in Pediatric Upper Extremity Fracture Care?

Introduction: Patient-reported outcomes in children can be assessed using self-report or caregiver proxy-report; however, self-reported and proxy-reported outcomes often vary between respondents, a phenomenon called cross-informant variance. This phenomenon has not been studied in pediatric fracture care. This study compares self-reported and proxy-reported patient-reported outcomes in children being treated for upper extremity fractures.

Study on the mechanical properties of unloaded damage sandstone under dry-wet and freeze-thaw cycling conditions.

Understanding he impact of dry-wet and freeze-thaw cycles on the mechanical properties of unloaded damaged rock masses in reservoir bank slopes is crucial for revealing the deformation and failure mechanisms in artificially excavated slope rock masses within fluctuation zones. To address, the study focuses on unloaded damaged samples subjected to excavation disturbances, conducting various cycles of dry-wet and freeze-thaw treatment along with uniaxial and triaxial re-loading tests. A damage statistical constitutive model was established based on the experimental results and validated using numerical simulation methods.

Ambient pollution at hip fracture units and impact on mortality and post-operative delirium: A hormetic effect?

There is increasing awareness of the deleterious effects of ambient pollution. The World Health Organisation (WHO) has recently advocated new safe limits of annual exposure for the three pre-dominant pollutants: fine particulate matter (PM2.5), coarse particulate matter (PM10) and nitrogen dioxide; namely 5μg/m3, 15μg/m3 and 10gμ/m3 respectively.

Biomechanical assessment of Kirschner wires integrated with a novel external fixation device for treatment of pediatric supracondylar humeral fracture: a finite element analysis.

Background: Pediatric supracondylar humeral fractures present considerable surgical challenges due to the difficulty of achieving proper fracture alignment and stable fixation while avoiding injury to the ulnar nerve. This study assesses the biomechanical performance of a novel Kirschner wire (K-wire) fixation device (KFD), designed to enhance stability and reduce complications linked to traditional K-wire configurations.

Methods: Using finite element analysis (FEA), we evaluated four fixation strategies for treatment of pediatric supracondylar humeral simple transverse fractures: crossed pin fixation, crossed pin fixation with KFD, two lateral pin fixation, and two lateral pin fixation with KFD, under various mechanical loads.

Unicortical Versus Bicortical Proximal Locking Screw for Prevention of Peri-Implant Fracture: A Biomechanical Analysis of an Osteoporotic Distal Radius Model.

Purpose: Osteoporotic patients are at risk of peri-implant fractures after distal radius fixation. A unicortical screw in the proximal hole of the plate can theoretically decrease stress riser formation by eliminating the hole in the far bone cortex. This construct has been proposed in orthopedic literature to prevent peri-implant fractures but has not been tested in an osteoporotic distal radius model.

Upper-Extremity Injuries in a Level 1 Trauma Center Following Border Wall Height Increase.

Purpose: From 2018-2019, the height of over 400 miles of southern border wall was raised to 30 feet. Our aim was to evaluate the impact of the increase in border wall height on upper-extremity injuries sustained via barrier fall.

Methods: A retrospective review of patients admitted with upper-extremity injuries sustained via border wall fall between January 2015 and December 2022 at a Level 1 trauma center serving the United States-Mexico border.

Mechanical stability of the proximal tibia with different bone formations after plate removal in medial opening-wedge high tibial osteotomy: a finite element analysis.

Background: No clear agreement exists on the degree of bone formation required to remove a metal plate without correction loss after medial opening-wedge high tibial osteotomy (MOWHTO). We aimed to investigate the mechanical stability of the proximal tibia with different bone formations after plate removal in MOWHTO using finite element models and determine the extent of bone formation when the plate can be removed without correction loss.

Methods: The MOWHTO models with 5, 10, and 15 mm opening gaps were generated.

Characteristics and mechanical mechanisms of intervertebral disc degeneration in old thoracolumbar fractures with kyphosis: clinical observations and finite element analyses.

Background: Low back pain is a common complication in patients with old thoracolumbar fractures with kyphosis (OTLFK), and intervertebral disc degeneration (IDD) is a major contributor. Mechanical abnormalities are believed to play a key role in the development to IDD. This study aimed to investigate the characteristics of lumbar disc degeneration and underlying mechanical mechanisms in patients with OTLFK.

Comparative 3D finite element analysis of intramedullary fixation versus locking plate fixation in calcaneal fractures using micro-CT image technology.

Objective: Calcaneal fracture fixation remains a challenging procedure in orthopedics, with computational tools increasingly aiding in the optimization of preoperative planning. To compare the biomechanical stability of intramedullary fixation and locking plate fixation for Sanders II and III calcaneal fractures by three-dimensional (3D) finite element analysis and to provide a theoretical basis for clinical application.

Methods: The Computed Tomography (CT) images were segmented using Mimics software (Materialise NV, Belgium) to identify the region of interest based on threshold segmentation.

Stretchable and self-healing carboxymethyl cellulose/polyacrylic acid conductive hydrogels for monitoring human motions and electrophysiological signals.

Stretchable conductive hydrogels have attracted great attention in flexible electronics. Nevertheless, conductive hydrogels would suffer from an inevitable damage during use, significantly reducing the reliability and limiting the practicability. Herein, stretchable and self-healing conductive hydrogels are designed form carboxymethyl cellulose (CMC), polyacrylic acid (PAA), and Fe, which are applied for monitoring human motions and electrophysiological signals.

Comparative finite element analyses of stress exerted on the dentin by intraradicular posts.

Unlabelled: The amount of residual dentin thickness and tooth position in the dental arch is crucial to determine whether an intraradicular post should be used. This study aimed to compare stress distribution on the root dentin of an endodontically treated tooth rehabilitated with CAD/CAM milled glass fiber posts (MP), cast metal posts (CMP), or prefabricated posts (PP) with or without ferrule support, using the finite element method.

Materials And Methods: A human upper central incisor was selected, scanned, and treated endodontically.

Fracture Dynamics in Silicon Anode Solid-State Batteries.

Solid-state batteries (SSBs) with silicon anodes could enable improved safety and energy density compared to lithium-ion batteries. However, degradation arising from the massive volumetric changes of silicon anodes during cycling is not well understood in solid-state systems. Here, we use X-ray computed microtomography to reveal micro- to macro-scale chemo-mechanical degradation processes of silicon anodes in SSBs.

Assessing shear bond strength of various surface treatments of 3D-printed provisional material with bis-acryl relining material.

Objective: Marginal adaptation of the provisional restoration often requires relining from relining materials. This study determined the effects of surface treatments on the shear bond strength (SBS) between 3D-printed provisional and bis-acryl relining materials.

Materials And Methods: The 3D-printed provisional specimens (9 × 9 × 2 mm) were prepared using methacrylate-based material.

Perceived barriers and facilitators of staff recruiting participants to a randomised controlled trial of a community rehabilitation intervention following hip fracture.

Background: Randomised controlled trials (RCTs) often struggle with recruitment and many need extensions which leads to delayed implementation of effective interventions. Recruitment to complex intervention trials have similar difficulties. Alongside this, the COVID-19 pandemic had a major impact upon trial recruitment.

Medial meniscus posterior root tears with advanced osteoarthritis or subchondral insufficiency fracture are good indications for unicompartmental knee arthroplasty at a minimum 2-year follow-up.

Introduction: The outcomes of unicompartmental knee arthroplasty (UKA) in the presence and absence of medial meniscus posterior root tears (MMPRTs) have not been compared. This study compared the characteristics and clinical outcomes of patients undergoing UKA with and without MMPRTs.

Materials And Methods: This study analyzed 68 patients.

Internal brace augmentation in elbow varus posteromedial rotatory instability (VPMRI) allows early rehabilitation and prevents stiffness.

Purpose: Varus posteromedial rotatory instability (VPMRI) involves anteromedial coronoid fracture (AMCF), lateral ulnar collateral ligament (LUCL), and medial collateral ligament (MCL) injury. There is no general consensus regarding the surgical treatment, but most surgeons recommend internal fixation of the coronoid along with primary ligament repair. This methodology involves postoperative immobilization to allow ligament healing, occasionally associated with stiffness.

Multi-scale inferomedial femoral neck bone quality in type 2 diabetes patients with fragility fracture.

Both trabecular and cortical bone undergo changes at multiple scales. We previously demonstrated the multi-scale changes in trabecular bone quality that contribute to bone fragility in type 2 diabetes (T2D). The link between increased fragility in T2D and multi-scale changes in cortical bone and their interaction with glycation remains unclear.

Venous Thromboembolism at Low Risk of Recurrence in Young Women: Stress and Violence Associated with Recurrence. An International Case-Control Study.

Background:  In young women with venous thromboembolism (VTE) related to weak transient risk factors, it remains unknown whether stress levels and intimate partner violence (IPV) are associated with recurrence. The VTE-WEAK study aims to investigate the association between perceived stress and IPV with a recurrence of VTE in women with a first episode of VTE due to combined oral contraceptives, pregnancy-puerperium, minor trauma/fracture, brief surgery, infection or brief immobility, and not using antithrombotic prophylaxis.

Material And Methods:  We performed a multicenter, international, observational, retrospective study on women referred for thrombophilia screening who were subsequently monitored.

Biomechanical stability of magnesium plate and screw fixation systems in LeFort I osteotomy: a three-dimensional finite element analysis.

Background: Titanium (Ti-6Al-4 V) is used for fixation in LeFort I osteotomy, a procedure for treating midface deformities. This study assessed the biomechanical stabilities of two Mg alloys (WE43 and ZK60) as biodegradable alternatives and compared them against Ti using finite element analyses. The LeFort I osteotomy procedure was simulated, and various plate and screw configurations were tested.