Nanomolar PFOA Concentrations Affect Lipid Membrane Structure: Consequences for Bioconcentration Mechanisms.

Independent methods show that sub-microMolar concentrations of perfluorooctanoic acid (PFOA), a member of the PFAS family of "forever chemicals", change the properties of DPPC vesicle bilayers. Specifically, calorimetry measurements show that PFOA at concentrations as low as 0.1 nM lowers DPPC's gel-liquid crystalline transition enthalpy by several J/g without changing the transition temperature (), and dynamic light scattering (DLS) data illustrate that PFOA markedly broadens the size distribution of DPPC vesicles.

Prospective Noninvasive Hemoglobin Monitoring in the Outpatient Total Joint Arthroplasty Setting.

Background: Total joint arthroplasty (TJA) is increasingly being performed as an outpatient (i.e., same-day discharge) procedure.

Retaining a Well-fixed Cone During Revision Total Knee Arthroplasty: Surgical Technique and Outcomes.

Unlabelled: Metaphyseal cones are frequently used in revision total knee arthroplasties (TKAs). However, during subsequent aseptic re-revisions, removing a well-fixed cone can be difficult. One innovative option is to retain the well-fixed cone and cement a new, stemmed revision component through the retained cone, yet minimal data exist on this technique.

Why Are Contemporary Primary Ceramic-on-Highly Crosslinked Polyethylene Total Hip Arthroplasties Failing? An Analysis of Over 5,500 Cases.

Background: Ceramic-on-highly crosslinked polyethylene (HXLPE) has become the most common bearing surface utilized in primary total hip arthroplasty (THA). The purpose of this study was to determine the implant survivorship and clinical outcomes of THAs with ceramic-on-HXLPE in a large single-institutional series.

Methods: We identified 5,536 primary THAs performed from 2007 to 2017 using a ceramic-on-HXLPE bearing through our total joint registry.

How Does the Physician Patient Fare After Primary Total Hip and Knee Arthroplasty?

Background: Physician patients requiring surgery present with occupational risks and personality traits that may affect outcomes. This study compared implant survivorship, complications, and clinical outcomes of physicians undergoing primary total hip arthroplasty (THA) or total knee arthroplasty (TKA).

Methods: A retrospective review of our institutional total joint registry identified 185 physicians undergoing primary THA (n = 94) or TKA (n = 91).

A Randomized Clinical Trial of Direct Anterior Versus Mini-Posterior Total Hip Arthroplasty: Small, Early Functional Differences Did Not Lead to Meaningful Clinical Differences at 7.5 Years.

Background: Our previously reported randomized clinical trial of direct anterior approach (DAA) versus mini-posterior approach (MPA) total hip arthroplasty showed slightly faster initial recovery for patients who had a DAA and no differences in complications or clinical or radiographic outcomes beyond 8 weeks. The aims of the current study were to determine if early advantages of DAA led to meaningful clinical differences beyond 5 years and to identify differences in midterm complications.

Methods: Of the 101 original patients, 93 were eligible for follow-up at a mean of 7.

Modular fluted tapered stems in two-stage reimplantation of previously infected total hip arthroplasties.

Aims: Uncemented implants are now commonly used at reimplantation of a two-stage revision total hip arthoplasty (THA) following periprosthetic joint infection (PJI). However, there is a paucity of data on the performance of the most commonly used uncemented femoral implants - modular fluted tapered (MFT) femoral components - in this setting. This study evaluated implant survival, radiological results, and clinical outcomes in a large cohort of reimplantation THAs using MFT components.

Contemporary Aseptic Revision Total Hip Arthroplasty in Patients ≤50 Years of Age: Results of >500 Cases.

Background: There has been a paucity of long-term outcomes data on aseptic revision total hip arthroplasties (THAs) in the young adult population. The purpose of this study was to evaluate implant survivorship, complications, and clinical outcomes in a large cohort of contemporary aseptic revision THAs in patients ≤50 years of age at the time of the surgical procedure.

Methods: We identified 545 aseptic revision THAs performed at a single academic institution from 2000 to 2020 in patients who were 18 to 50 years of age.

Cemented dual-mobility constructs in uncemented revision acetabular components.

Aims: Dislocation remains a leading cause of failure following revision total hip arthroplasty (THA). While dual-mobility (DM) bearings have been shown to mitigate this risk, options are limited when retaining or implanting an uncemented shell without modular DM options. In these circumstances, a monoblock DM cup, designed for cementing, can be cemented into an uncemented acetabular shell.

Surgical Approach and Body Mass Index Impact Risk of Wound Complications Following Total Hip Arthroplasty.

Background: Previous studies have suggested that wound complications may differ by surgical approach after total hip arthroplasty (THA), with particular attention toward the direct anterior approach (DAA). However, there is a paucity of data documenting wound complication rates by surgical approach and the impact of concomitant patient factors, namely body mass index (BMI). This investigation sought to determine the rates of wound complications by surgical approach and identify BMI thresholds that portend differential risk.

Knee Arthroscopy Following Total Knee Arthroplasty is Not Associated With an Elevated Risk of Infection.

Background: Recent literature has suggested that knee arthroscopy (KA) following ipsilateral primary total knee arthroplasty (TKA) may be associated with an increased risk of periprosthetic joint infection (PJI). However, prior studies on this subject have relied on insurance databases or have lacked control groups for comparison. This study aimed to evaluate the risk of PJI in patients undergoing ipsilateral KA after primary TKA at a single institution.

Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty.

Background: Removal of well-fixed femoral components during revision total hip arthroplasty (THA) can be difficult and time-consuming, leading to numerous complications, such as femoral perforation, bone loss, and fracture. Extended trochanteric osteotomies (ETOs), which provide wide exposure and direct access to the femoral canal under controlled conditions, have become a popular method to circumvent these challenges. ETOs were popularized by Wagner (i.

Making the cut: a technical note and literature review of Bernese periacetabular osteotomy techniques with special attention to ischial osteotomy initiation and completion with an inside to anterior curved osteotomy.

Periacetabular osteotomy includes a fluoroscopy-guided ischial cut without direct visualization. Previously described techniques include a mediolateral ischial cortex cut, which is associated with the risk of injuring nearby nerves. Another drawback of that technique is the difficulty connecting an ischial cortex cut with a retroacetabular cut due to orthogonal nature of the osteotomy.

Total Hip Arthroplasty Following Operative Fixation of Acetabular Fracture: A Contemporary Series.

Background: Total hip arthroplasty (THA) is the operation of choice for salvage of post-traumatic arthritis following acetabular fracture. While high failure rates have been reported for these procedures, existing literature reports mainly on historical implant designs and techniques. We aimed to describe implant survivorships, complications, radiographic results, and clinical outcomes of contemporary THA following prior open reduction internal fixation (ORIF) of an acetabular fracture.

l-Phenylalanine Partitioning Mechanisms in Model Biological Membranes.

Time-resolved fluorescence spectroscopy in combination with differential scanning calorimetry (DSC) was used to study the chemical interactions that occur when l-phenylalanine is introduced to solutions containing phosphatidylcholine vesicles. Studies reported in this work address open questions about l-Phe's affinity for lipid vesicle bilayers, the effects of l-Phe partitioning on bilayer properties, l-Phe's solvation within a lipid bilayer, and the amount of l-Phe within that local solvation environment. DSC data show that l-Phe reduces the amount of heat necessary to melt saturated phosphatidylcholine bilayers from their gel to liquid-crystalline state but does not change the transition temperature ().

Radiographic Accuracy of Malseated Dual-Mobility Liners Varies Based on Implant Design.

Background: Dual-mobility constructs have gained popularity to mitigate dislocations after high-risk primary and revision total hip arthroplasties. Contemporary data have indicated that malseating of modular dual-mobility liners occurs in up to 6% of cases. The purpose of this cadaveric-based radiographic study was to determine the ability to accurately determine if modular dual-mobility liners were seated.

Modular Proximal Body Exchange for Re-Revision Total Hip Arthroplasty: Rarely Utilized and Moderately Successful.

Background: Modular fluted tapered stems (MFTSs) are commonly used in revision total hip arthroplasty (THA) and provide the option of exchanging the proximal modular portion to address future surgical problems without complete femoral revision. We are unaware of any data documenting the frequencies, indications, and outcomes of modular proximal body exchange in re-revision THA.

Methods: Between 1997 and 2019, we performed 57 modular proximal body exchanges among 8,079 revision THAs at our institution.

Can Selected Use of Cemented and Uncemented Femoral Components in a Broad Population Produce Comparable Results Following Primary Total Hip Arthroplasty for Osteoarthritis?

Background: Registry data have demonstrated lower rates of revision and periprosthetic fracture in select cohorts with cemented femoral fixation at primary total hip arthroplasty. Whether this is true of all component designs is not known. We hypothesized that selected use of ream-and-broach triple-tapered uncemented stem designs may provide comparable results to cemented stems.

Comparative Survival of Contemporary Cementless Acetabular Components Following Revision Total Hip Arthroplasty.

Background: The advent of highly porous ingrowth surfaces and highly crosslinked polyethylene has been expected to improve implant survivorship in revision total hip arthroplasty. Therefore, we sought to evaluate the survival of several contemporary acetabular designs following revision total hip arthroplasty.

Methods: Acetabular revisions performed from 2000 to 2019 were identified from our institutional total joint registry.

Total Knee Arthroplasty in Patients Who had a Prior Anterior Cruciate Ligament Reconstruction: Balancing Remains the Issue.

Background: Following anterior cruciate ligament (ACL) injury, 20% of patients will develop osteoarthritis. Despite this, there remains a paucity of data describing outcomes of total knee arthroplasty (TKA) after prior ACL reconstruction. We aimed to describe survivorships, complications, radiographic results, and clinical outcomes of TKA after ACL reconstruction in one of the largest series to date.

AAHKS Surgical Techniques & Technologies Award: Resurfacing the Thin Native Patella: Is It Safe?

Background: Whether to resurface the patella during total knee arthroplasty (TKA) remains debated. One often cited reason for not resurfacing is inadequate patellar thickness. The aim of this study was to describe the implant survivorships, reoperations, complications and clinical outcomes in patients who underwent patellar resurfacing of a thin native patella.

Orthopedic Surgery and Anesthesiology Surgical Improvement Strategies Project - Phase III Outcomes.

Background: Our institution initiated the Orthopedic Surgery and Anesthesiology Surgical Improvement Strategies (OASIS) project in 2017 to improve the quality and efficiency for hip and knee arthroplasties. Phase III of this project aimed to: 1) increase same-day discharge (SDD) of primary total joint arthroplasties (TJAs) to 20%; 2) maintain or improve 30-day readmission rates; and 3) realize cost savings and revenue increases.

Methods: All primary TJAs performed between 2021 and 2022 represented our study cohort, with those in 2019 (prepandemic) establishing the baseline cohort.

Creation of a Total Hip Arthroplasty Patient-Specific Dislocation Risk Calculator.

Background: Many risk factors have been described for dislocation following total hip arthroplasty (THA), yet a patient-specific risk assessment tool remains elusive. The purpose of this study was to develop a high-dimensional, patient-specific risk-stratification nomogram that allows dynamic risk modification based on operative decisions.

Methods: In this study, 29,349 THAs, including 21,978 primary and 7371 revision cases, performed between 1998 and 2018 were evaluated.