Intermediate-Term Survivorship of Total Hip Arthroplasty With a Proximally Coated Tapered-Wedge Femoral Stem: A Retrospective, Multi-Center Registry Review.

Background: Short tapered-wedge stems have been used frequently over the past decade, but long-term follow-up data are not readily available in the literature.

Methods: A retrospective outcomes review was conducted to assess survivorship and clinical outcomes for the TRI-LOCK® Bone Preservation Stem (TRI-LOCK BPS; DePuy Synthes, Warsaw, IN, USA), a proximally coated, tapered-wedge femoral stem.

Results: In a cohort of 2,040 hips, Kaplan-Meier survivorship estimates (95% CI {confidence interval}; N with further follow-up, where N is the number of hips remaining at each post-operative interval), with survivorship defined as no revision of any component for any reason were 96.

Polymethyl methacrylate cure time in simulated in vivo total knee arthroplasty versus in vitro conditions.

Background: The present means of confirming the cure of intra-operative polymethyl methacrylate (PMMA) cement are to wait for the remainder cement to harden. To our knowledge, there is no available technique to determine the precise moment of cure for in-vivo cement beneath the tibial tray. This study uses a novel means to determine cement curing time in two environments.

Dramatic Increases in Telehealth-Related Tweets during the Early COVID-19 Pandemic: A Sentiment Analysis.

The COVID-19 pandemic resulted in a large expansion of telehealth, but little is known about user sentiment. Tweets containing the terms "telehealth" and "telemedicine" were extracted (n = 192,430) from the official Twitter API between November 2019 and April 2020. A random subset of 2000 tweets was annotated by trained readers to classify tweets according to their content, including telehealth, sentiment, user type, and relation to COVID-19.

Routes of non-traditional entry into buprenorphine treatment programs.

Background: Excessive prescribing, increased potency of opioids, and increased availability of illicit heroin and synthetic analogs such as fentanyl has resulted in an increase of overdose fatalities. Medications for opioid use disorder (MOUD) significantly reduces the risk of overdose when compared with no treatment. Although the use of buprenorphine as an agonist treatment for opioid use disorder (OUD) is growing significantly, barriers remain which can prevent or delay treatment.

Variability in Distal Femoral Anatomy in Patients Undergoing Total Knee Arthroplasty: Measurements on 13,546 Computed Tomography Scans.

Proper mechanical and rotational alignment plays an important role in achieving the success of the total knee arthroplasty (TKA). The purpose of the present study was to retrospectively determine with computed tomography (CT) the distal femoral valgus angle (DFVA) and femoral rotation angle (FRA). Our cohort included 13,546 CT scans of patients undergoing TKA.

Tibial Slope is Highly Variable in Patients Undergoing Primary Total Knee Arthroplasty: Analysis of 13,546 Computed Tomography Scans.

The purpose of this study was to retrospectively measure with computed tomography (CT) the posterior tibial slope (PTS) to establish the average anatomy and the incidence of outliers in patients undergoing total knee arthroplasty (TKA). Our cohort included 13,546 arthritic patients: 8241 (61%) female; 5305 (39%) male. The average PTS angle was 7.

Ca(2+) permeation and/or binding to CaV1.1 fine-tunes skeletal muscle Ca(2+) signaling to sustain muscle function.

Background: Ca(2+) influx through CaV1.1 is not required for skeletal muscle excitation-contraction coupling, but whether Ca(2+) permeation through CaV1.1 during sustained muscle activity plays a functional role in mammalian skeletal muscle has not been assessed.

Short-term results of a custom triflange acetabular component for massive acetabular bone loss in revision THA.

Managing severe periacetabular bone loss during revision total hip arthroplasty (THA) is a challenging task. Multiple treatment options have been described. A custom triflanged acetabular component is a recent treatment option.

Dermabond efficacy in total joint arthroplasty wounds.

The goals of wound closure are a low infection rate and timely healing. Total joint arthroplasty (TJA) requires mobile recovery, and, therefore, a high-tension wound care environment. We conducted a study to compare the efficacy of high-viscosity Dermabond (Ethicon, Somerville, New Jersey) and the efficacy of surgical staples in healing high-tension, mobile surgical sites of TJA.

Unusual presentation of cobalt hypersensitivity in a patient with a metal-on-metal bearing in total hip arthroplasty.

Pain after hip arthroplasty is less likely to be attributed to dermal sensitivity from orthopedic implants. Unexplained persistent pain after hip arthroplasty typically leads to further investigation, occasionally revealing a metal sensitivity. Our case study presents an unusual finding of a delayed type IV cobalt hypersensitivity in a patient several years after use of cobalt in the contralateral hip.

Use of inpatient continuous passive motion versus no CPM in computer-assisted total knee arthroplasty.

Background: Continuous passive motion (CPM) has shown positive effects on tissue healing, edema, hemarthrosis, and joint function (L. Brosseau et al., 2004).

Low incidence of postoperative complications due to pin placement in computer-navigated total knee arthroplasty.

Computer-navigated joint arthroplasty surgery using optical tracking systems requires arrays fixated to bone via pins. Reports of fractures at pin sites have raised concern about safety. We reviewed the postoperative complications occurring in a single-surgeon series of 984 consecutive primary total knee arthroplasties.

Minimally invasive hip resurfacing compared to minimally invasive total hip arthroplasty.

Background: Since its March 2006 FDA approval in the United States, Birmingham hip resurfacing (BHR) has been a popular alternative to hip arthroplasty for the younger patient population. Data to date has shown a trend toward low incidence of dislocation and good survivorship.

Methods: 128 patients operated on by a single surgeon from July 2006 to December 2008 were reviewed for complications, pain, and function.

Technology and cost-effectiveness in knee arthroplasty: computer navigation and robotics.

Our aim in this article is to describe the impact that navigation technology has had on the market share of a community hospital and, specifically, to determine whether a high-volume surgeon using these technologies actually costs the hospital more than other surgeons at the same hospital and more than national means. In addition, we develop a comparable cost-effectiveness model for robotic technology in unicompartmental knee arthroplasty to demonstrate the potential cost-effectiveness at the same hospital.

Role of navigation in total hip arthroplasty.

Current uses of computed tomography-based and imageless navigation systems for total hip arthroplasty include proper placement of the acetabular component, measurement of limb-length changes, enablement of minimally invasive surgery, and proper placement of components for hip resurfacing procedures. This article provides an overview of the rationale for computer-assisted surgery in total hip arthroplasty and hip resurfacing. The experience of the senior author (M.

Imageless navigation in hip resurfacing: avoiding component malposition during the surgeon learning curve.

Background: Studies suggest that hip arthroplasty procedures performed in specialty hospitals or by physicians in practices with a high surgical volume are associated with a decreased rate of adverse outcomes related to component malpositioning. Little is known, however, about the influence of imageless computer navigation systems on the procedural experience of the surgeon and the subsequent alignment of implants in the setting of hip resurfacing arthroplasty.

Methods: Seventy-one consecutive hip resurfacing arthroplasties in which the components were placed with use of computer-assisted navigation were reviewed retrospectively.

Phosphorylation of ERK/MAP kinase is required for long-term potentiation in anatomically restricted regions of the lateral amygdala in vivo.

We have previously shown that the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/ MAPK) is transiently activated in anatomically restricted regions of the lateral amygdala (LA) following Pavlovian fear conditioning and that blockade of ERK/MAPK activation in the LA impairs both fear memory consolidation and long-term potentiation (LTP) in the amygdala, in vitro. The present experiments evaluated the role of the ERK/MAPK signaling cascade in LTP at thalamo-LA input synapses, in vivo. We first show that ERK/MAPK is transiently activated/phosphorylated in the LA at 5 min, but not 15 or 60 min, after high-frequency, but not low-frequency, stimulation of the auditory thalamus.

A novel method of loading samples onto mini-gels for SDS-PAGE: increased sensitivity and Western blots using sub-microgram quantities of protein.

Commercially available mini-gels for sodium dodecyl sulphate (SDS)-PAGE and Western blotting are limited both by the number of lanes that can be loaded per gel and the minimum amount of protein per lane that must be loaded. Here we describe a method for loading protein samples onto existing commercially available mini-gels that allows loading of 50 or more lanes per gel. The enhanced sensitivity of the method allows Western blotting with sub-microgram quantities of protein.

Regulation of dendritic morphogenesis by Ras-PI3K-Akt-mTOR and Ras-MAPK signaling pathways.

Dendritic arborization and spine formation are critical for the functioning of neurons. Although many proteins have been identified recently as regulators of dendritic morphogenesis, the intracellular signaling pathways that control these processes are not well understood. Here we report that the Ras-phosphatidylinositol 3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway plays pivotal roles in the regulation of many aspects of dendrite formation.

Computer-assisted surgery in total knee arthroplasty:recent advances.

Computer-assisted surgery (CAS) for total knee replacement was first approved for use in the U.S. in 2001.

Gene expression profiling and functional proteomic analysis reveal perturbed kinase-mediated signaling in genetic stroke susceptibility.

The stroke-prone spontaneously hypertensive rat (SHRSP) is a model of heritable hypertension-associated cerebrovascular injury. This study sought to compare SHRSP to the stroke-resistant SHR strain to identify genes and protein pathways whose expression and/or function was significantly altered between the strains prior to the onset of stroke. Cerebral cortex gene expression profiles from male SHRSPs and matched SHRs were examined by Affymetrix microarray analysis.

Protein kinase modulation of dendritic K+ channels in hippocampus involves a mitogen-activated protein kinase pathway.

We investigated mitogen-activated protein kinase (MAPK) modulation of dendritic, A-type K+ channels in CA1 pyramidal neurons in the hippocampus. Activation of cAMP-dependent protein kinase A (PKA) and protein kinase C (PKC) leads to an increase in the amplitude of backpropagating action potentials in distal dendrites through downregulation of transient K+ channels in CA1 pyramidal neurons in the hippocampus. We show here that both of these signaling pathways converge on extracellular-regulated kinases (ERK)-specific MAPK in mediating this reduction in dendritic K+ current, which is confirmed, in parallel, by biochemical assays using phosphospecific antibodies against the ppERK and pKv4.

Protein kinase signal transduction cascades in mammalian associative conditioning.

One of the most intriguing and intensely studied questions facing contemporary neuroscientists involves the elucidation of the physiological mechanisms that underlie learning and memory. Recent advances have given us a much more detailed understanding of the signal transduction mechanisms subserving learning in the intact animal. One fact that has become clear is that activation of protein kinases and phosphorylation of their downstream effectors play a critical role.