Survivorship and Outcomes of Femoral Neck Preserving Stems in Primary Total Hip Arthroplasty.

Background: Short-stem femoral implants (SSFIs) promote the preservation of bone in the femoral neck, reduce soft tissue disruption, and facilitate minimally invasive surgical techniques. The purpose of this study was to report the revision rate, complication rate, patient satisfaction, patient-reported outcomes, and radiographic outcomes of patients who underwent total hip arthroplasty (THA) with the Alteon Neck Preserving Femoral Stem (ANPS).

Methods: A prospectively maintained database was reviewed which analyzed 92 THAs between the years 2016 and 2018.

Intra-operative referencing technique is non-inferior to use of fluoroscopy for acetabular component positioning in anterior hip arthroplasty.

Background: Intra-operative fluoroscopy has been shown to improve the accuracy of acetabular component positioning when compared to no fluoroscopy in direct anterior approach (DAA) total hip arthroplasty (THA). Due to logistical reasons, our senior author has been performing DAA THA at one institution without the use of fluoroscopy and has created an intraoperative referencing technique to aid in acetabular component positioning. The purpose of this study is to evaluate the accuracy of acetabular component positioning using fluoroscopy when compared to an intra-operative referencing technique without fluoroscopy.

Cost Analysis of All-Polyethylene Compared to Metal-Backed Implants in Total Knee Arthroplasty.

Introduction: The growing trends of total knee arthroplasty (TKA) foreshadow an inevitable increase in the financial burden on healthcare expenditure estimated to almost nine billion dollars annually. This study aims to demonstrate the potential savings when using all-polyethylene (AP) compared to metal-backed (MB) tibial components and describes the cost variability amongst three major commercially available implants.

Materials And Methods: The cost of AP versus MB implants was analyzed using a large nationwide database, Emergency Care Research Institute (ECRI).

Systematic Review of Novel Synovial Fluid Markers and Polymerase Chain Reaction in the Diagnosis of Prosthetic Joint Infection.

Prosthetic joint infection (PJI) may be underreported because of difficulty in making a diagnosis, especially in infections with low-virulence organisms. Reports of PJI cases misdiagnosed as aseptic loosening suggest that current screening and diagnostic tools are not sensitive enough to detect all infections and that PJI likely is underdiagnosed. We reviewed the literature on recently developed novel synovial biomarkers and polymerase chain reaction (PCR) technologies, of which several have proved promising as highly sensitive and specific tools for detecting PJI.

Difficult-to-Detect Low-Grade Infections Responsible for Poor Outcomes in Total Knee Arthroplasty.

In this article, we present the case of a patient with a stiff, painful knee after total knee arthroplasty, and with erythrocyte sedimentation rate, C-reactive protein level, and synovial fluid analysis within normal limits. Open biopsy for cultures showed Propionibacterium acnes prosthetic joint infection, which was successfully treated with 2-stage revision and intravenous antibiotics.

Tears Falling on Goosebumps: Co-occurrence of Emotional Lacrimation and Emotional Piloerection Indicates a Psychophysiological Climax in Emotional Arousal.

This psychophysiological study is the first to examine the relationship between emotional tears and emotional piloerection (i.e., goosebumps).

Effect of Static Compressive Strain, Anisotropy, and Tissue Region on the Diffusion of Glucose in Meniscus Fibrocartilage.

Osteoarthritis (OA) is a significant socio-economic concern, affecting millions of individuals each year. Degeneration of the meniscus of the knee is often associated with OA, yet the relationship between the two is not well understood. As a nearly avascular tissue, the meniscus must rely on diffusive transport for nutritional supply to cells.

Force field analysis suggests a lowering of diffusion barriers in atomic manipulation due to presence of STM tip.

We study the physics of atomic manipulation of CO on a Cu(111) surface by combined scanning tunneling microscopy and atomic force microscopy at liquid helium temperatures. In atomic manipulation, an adsorbed atom or molecule is arranged on the surface using the interaction of the adsorbate with substrate and tip. While previous experiments are consistent with a linear superposition model of tip and substrate forces, we find that the force threshold depends on the force field of the tip.

Surface structure. Subatomic resolution force microscopy reveals internal structure and adsorption sites of small iron clusters.

Clusters built from individual iron atoms adsorbed on surfaces (adatoms) were investigated by atomic force microscopy (AFM) with subatomic resolution. Single copper and iron adatoms appeared as toroidal structures and multiatom clusters as connected structures, showing each individual atom as a torus. For single adatoms, the toroidal shape of the AFM image depends on the bonding symmetry of the adatom to the underlying structure [twofold for copper on copper(110) and threefold for iron on copper(111)].

Outcomes of total joint arthroplasty in HIV patients.

Background: Advancement in human immunodeficiency virus (HIV) therapies has increased life expectancy. The need for joint replacement is expected to increase as this population develops degenerative changes from aging and avascular necrosis (AVN). Studies have shown a higher risk of peri-prosthetic joint infections (PJI) in HIV patients.

CO tip functionalization inverts atomic force microscopy contrast via short-range electrostatic forces.

We investigate insulating Cu2N islands grown on Cu(100) by means of combined scanning tunneling microscopy and atomic force microscopy with two vastly different tips: a bare metal tip and a CO-terminated tip. We use scanning tunneling microscopy data as proposed by Choi, Ruggiero, and Gupta to unambiguously identify atomic positions. Atomic force microscopy images taken with the two different tips show an inverted contrast over Cu2N.

qPlus magnetic force microscopy in frequency-modulation mode with millihertz resolution.

Magnetic force microscopy (MFM) allows one to image the domain structure of ferromagnetic samples by probing the dipole forces between a magnetic probe tip and a magnetic sample. The magnetic domain structure of the sample depends on the alignment of the individual atomic magnetic moments. It is desirable to be able to image both individual atoms and domain structures with a single probe.

Extracellular matrix-induced transforming growth factor-beta receptor signaling dynamics.

Matrix remodeling, degradation, inflammation and invasion liberate peptide fragments that can subsequently interact with cells in an attachment-independent manner. Such 'soluble' matrix components, including collagens, fibronectin and laminin, induced Smad activation (termed crosstalk signaling), which follows a similar chronological sequence and R-Smad specificity as induced by transforming growth factor (TGF)-beta1. Smad4 nuclear translocation occurred in response to collagen binding, indicating downstream signal propagation.

Primary lymphoma of bone in adult patients.

Background: The low incidence of primary lymphoma of bone (PLB) has led to discrepancies in classification as well as difficulty in prognostication. The authors of this report used the Surveillance, Epidemiology, and End Results (SEER) database to analyze a large, population-based cohort of adult patients with this disease. The database provides a standardized classification and documentation of outcomes and enables a meaningful evaluation of prognostic factors.

Ewing sarcoma demonstrates racial disparities in incidence-related and sex-related differences in outcome: an analysis of 1631 cases from the SEER database, 1973-2005.

Background: Previous reports of Ewing sarcoma cohorts suggested that there is a difference in incidence according to racial origin. However, to the authors' knowledge, this finding has never been tested in a population-based database, and the impact of race on clinical outcome and the significance of known risk factors stratified to racial groups have not been reported.

Methods: Patients who had Ewing sarcoma diagnosed between 1973 and 2005 were identified in the Surveillance, Epidemiology, and End Results database.

Fibular osteosarcomas: contaminated margins may not impact survival.

The fibula is an expendable bone which when affected by primary malignancy may simplify treatment and improve outcome. This concept was questioned previously in a study showing a high rate of inadequate margins at surgical resection. We asked whether margin status and other dependent variables affect survival.

Dislocation rate after hip hemiarthroplasty in patients with tumor-related conditions.

Background: Hemiarthroplasty is frequently used to treat femoral neck insufficiency resulting from neoplastic disease in the proximal part of the femur. The authors of a recent study analyzed the dislocation rates following hemiarthroplasty but excluded patients with tumor involvement of the site of the surgery as they hypothesized that the dislocation rates would be markedly higher in such patients. The current study was performed to compare the dislocation rate following hemiarthroplasties performed in patients without tumor involvement with the rate following hemiarthroplasties in patients with tumor involvement of the surgical site.

Scapular chondrosarcomas have high rates of local recurrence and metastasis.

This is the first report of a large series of patients with scapular chondrosarcomas. The grade distributions, locations of the tumors in the scapula, surgical techniques, status of margins, chondrosarcoma subtypes, Enneking stages, adjuvant therapies, local recurrence rates, metastasis rates, and survival prognoses of patients with scapular chondrosarcoma were evaluated. Forty-seven patients treated between 1921 and 1999 were analyzed retrospectively.

Patient survival after hip arthroplasty for metastatic disease of the hip.

Background: The hip joint is a common location for metastatic disease. Actual as well as impending fractures at this site are frequently due to mechanical instability after tumor invasion and are usually treated surgically with hip arthroplasty. The objective of this study was to analyze survival and influences on survival after hip arthroplasty for metastatic hip disease.

Signaling "cross-talk" between TGF-beta1 and ECM signals in chondrocytic cells.

The objective of this investigation was to clarify how the integrin pathway modulates downstream effectors of the TGF-beta1 pathway in chondrocytic cell signaling. The levels of Smad2 and Smad3 phosphorylation upon TGF-beta1 or alpha2beta1 integrin (Type II collagen) stimulation were analyzed by Western blotting techniques. Cellular response was determined by quantitation of procollagen gene expression.

Signaling through a novel domain of gp130 mediates cell proliferation and activation of Hck and Erk kinases.

Interleukin-6 (IL-6) induces the activation of the Src family kinase Hck, which is associated with the IL-6 receptor beta-chain, gp130. Here we describe the identification of an "acidic" domain comprising amino acids 771 to 811 of gp130 as a binding region for Hck, which mediates proliferative signaling. The deletion of this region of gp130 (i.