A Tool to Estimate Risk of 30-day Mortality and Complications After Hip Fracture Surgery: Accurate Enough for Some but Not All Purposes? A Study From the ACS-NSQIP Database.

Background: Surgical repair of hip fracture carries substantial short-term risks of mortality and complications. The risk-reward calculus for most patients with hip fractures favors surgical repair. However, some patients have low prefracture functioning, frailty, and/or very high risk of postoperative mortality, making the choice between surgical and nonsurgical management more difficult.

What Factors Lead to Racial Disparities in Outcomes After Total Knee Arthroplasty?

Total knee arthroplasty (TKA) is one of the most commonly performed, major elective surgeries in the USA. African American TKA patients on average experience worse clinical outcomes than whites, including lower improvements in patient-reported outcomes and higher rates of complications, hospital readmissions, and reoperations. The mechanisms leading to these racial health disparities are unclear, but likely involve patient, provider, healthcare system, and societal factors.

Hepatitis C infection and complication rates after total shoulder arthroplasty in United States veterans.

Background: Few studies have evaluated the effect of hepatitis C (HCV) on primary total shoulder arthroplasty (TSA). Our purpose was to determine if HCV infection is associated with increased complication rates after TSA in United States (US) veterans and, secondarily, to determine if preoperative HCV treatment with direct-acting antivirals (DAAs) affects postoperative complication rates.

Methods: US Department of Veterans Affairs (VA) data sets were used to retrospectively identify patients without HCV, patients with untreated HCV, and patients with HCV treated with DAAs who underwent TSA from 2014 to 2019.

Antibiotic-Laden Bone Cement Use and Revision Risk After Primary Total Knee Arthroplasty in U.S. Veterans.

Background: It is controversial whether the use of antibiotic-laden bone cement (ALBC) in primary total knee arthroplasty (TKA) affects periprosthetic joint infection (PJI) or revision rates. The impact of ALBC on outcomes of primary TKA have not been previously investigated in U.S.

Can Machine Learning Methods Produce Accurate and Easy-to-Use Preoperative Prediction Models of One-Year Improvements in Pain and Functioning After Knee Arthroplasty?

Background: Approximately 15%-20% of total knee arthroplasty (TKA) patients do not experience clinically meaningful improvements. We sought to compare the accuracy and parsimony of several machine learning strategies for developing predictive models of failing to experience minimal clinically important differences in patient-reported outcome measures (PROMs) 1 year after TKA.

Methods: Patients (N = 587) in 3 large Veteran Health Administration facilities completed PROMs before and 1 year after TKA (92% follow-up).

Social Determinants of Health and Patient-Reported Outcomes Following Total Hip and Knee Arthroplasty in Veterans.

Background: Social determinants of health (SDOH) are the conditions in which people are born, grow, live, work, and age. They are associated with disparities in outcomes following total joint arthroplasty (TJA). These disparities occur even in equal-access healthcare systems such as the Veterans Health Administration (VHA).

Comparing Methods to Determine the Minimal Clinically Important Differences in Patient-Reported Outcome Measures for Veterans Undergoing Elective Total Hip or Knee Arthroplasty in Veterans Health Administration Hospitals.

Importance: The minimal clinically important difference (MCID) in a patient-reported outcome measure (PROM) is the smallest change that patients perceive as beneficial. Accurate MCIDs are required when PROMs are used to evaluate the value of surgical interventions.

Objective: To use well-defined distribution-based and anchor-based methods to calculate MCIDs in the Hip Disability and Osteoarthritis Outcome Score (HOOS) and in the Knee Injury and Osteoarthritis Outcome Score (KOOS) for veterans undergoing primary total hip arthroplasty or total knee arthroplasty.

Comparison of Periarticular Infiltration and Combination Delivery of Local Anesthetics for Reducing Pain and Opioid Consumption after Total Knee Arthroplasty.

Surgical-site delivery of local anesthetics decreases pain and opioid consumption after total knee arthroplasty (TKA). The optimal route of administration is unknown. We compared local anesthetic delivery using periarticular soft-tissue infiltration to delivery using a combination of preimplantation immersion and intra-articular injection (combination treatment).

Osteocyte dysfunction promotes osteoarthritis through MMP13-dependent suppression of subchondral bone homeostasis.

Osteoarthritis (OA), long considered a primary disorder of articular cartilage, is commonly associated with subchondral bone sclerosis. However, the cellular mechanisms responsible for changes to subchondral bone in OA, and the extent to which these changes are drivers of or a secondary reaction to cartilage degeneration, remain unclear. In knee joints from human patients with end-stage OA, we found evidence of profound defects in osteocyte function.

Does Implant Choice Affect the Episode Cost of Pertrochanteric Hip Fracture for US Veterans?

Objective: To investigate an association between a surgeon's choice of a cephalomedullary nail (CMN) or sliding hip screw (SHS) with the cost of treating a pertrochanteric hip fracture.

Design: Multicenter retrospective cohort study.

Setting: US Veterans Health Administration Sierra Pacific Network.

Preoperative Treatment of Hepatitis C Is Associated With Lower Prosthetic Joint Infection Rates in US Veterans.

Background: Hepatitis C virus (HCV) is associated with poorer outcomes in total joint arthroplasty (TJA). Recently, oral direct-acting antivirals (DAAs) have become available for HCV curative treatment. The goal of this study is to determine if HCV may be a modifiable risk factor in TJA by comparing postoperative complications among patients with and without preoperative treatment for HCV.

Freedom From Opioids After Total Knee Arthroplasty.

Background: In the United States, opioids are commonly prescribed to treat knee pain after total knee arthroplasty (TKA). While surgery leads to decreased pain in most patients, a sizable minority continue to experience severe pain and consume opioids chronically after TKA. We sought to determine the population-level effect of TKA on opioid consumption by detailing the pattern of opioid prescriptions before and after surgery.

Can Machine Learning Methods Produce Accurate and Easy-to-use Prediction Models of 30-day Complications and Mortality After Knee or Hip Arthroplasty?

Background: Existing universal and procedure-specific surgical risk prediction models of death and major complications after elective total joint arthroplasty (TJA) have limitations including poor transparency, poor to modest accuracy, and insufficient validation to establish performance across diverse settings. Thus, the need remains for accurate and validated prediction models for use in preoperative management, informed consent, shared decision-making, and risk adjustment for reimbursement.

Questions/purposes: The purpose of this study was to use machine learning methods and large national databases to develop and validate (both internally and externally) parsimonious risk-prediction models for mortality and complications after TJA.

Repurposing Human Osteoarthritic Cartilage as a Bone Graft Substitute in an Athymic Rat Posterolateral Spinal Fusion Model.

Background: Spinal fusion involves both endochondral and intramembranous bone formation. We previously demonstrated that endochondral cartilage grafts that were derived from human osteoarthritic (OA) articular cartilage can be used as a bone graft in mouse models. We hypothesized that OA cartilage could also be recycled and repurposed as a bone graft substitute in a posterolateral lumbar spinal fusion model in athymic rats.

American Joint Replacement Registry Risk Calculator Does Not Predict 90-day Mortality in Veterans Undergoing Total Joint Replacement.

Background: The American Joint Replacement Registry (AJRR) Total Joint Risk Calculator uses demographic and clinical parameters to provide risk estimates for 90-day mortality and 2-year periprosthetic joint infection (PJI). The tool is intended to help surgeons counsel their Medicare-eligible patients about their risk of death and PJI after total joint arthroplasty (TJA). However, for a predictive risk model to be useful, it must be accurate when applied to new patients; this has yet to be established for this calculator.

Acute Pain Is Associated With Chronic Opioid Use After Total Knee Arthroplasty.

Background And Objectives: Pain scores are routinely reported in clinical practice, and we wanted to examine whether this routinely measured, patient-reported variable provides prognostic information, especially with regard to chronic opioid use, after taking preoperative and perioperative variables into account in a preoperative opioid user population.

Methods: In 32,874 preoperative opioid users undergoing primary total knee arthroplasty at Veterans Affairs hospitals between 2010 and 2015, we compared preoperative and perioperative characteristics in patients reporting lower versus higher acute pain (scores ≤4/10 vs >4/10 averaged over days 1-3). We calculated the propensity for lower acute pain based on all available data.

Prediction Models for 30-Day Mortality and Complications After Total Knee and Hip Arthroplasties for Veteran Health Administration Patients With Osteoarthritis.

Background: Statistical models to preoperatively predict patients' risk of death and major complications after total joint arthroplasty (TJA) could improve the quality of preoperative management and informed consent. Although risk models for TJA exist, they have limitations including poor transparency and/or unknown or poor performance. Thus, it is currently impossible to know how well currently available models predict short-term complications after TJA, or if newly developed models are more accurate.

The Effects of Topical Vancomycin on Mesenchymal Stem Cells: More May Not Be Better.

Background: The use of topical vancomycin is increasingly popular in spine surgery. Large retrospective reviews suggest that topical vancomycin provides a cost-effective decrease in post-operative infection. Currently, there is little that is known about the maximum dose that can be applied locally.

A Simple Method Associated With Reduced Opioid Consumption After Total Knee Arthroplasty.

Background: Most patients experience moderate to severe pain after total knee arthroplasty (TKA). We hypothesized that intraoperative treatment of cut bone surfaces with local anesthetic (preimplantation immersion anesthesia, PIA) would lead to decreased postoperative pain and opioid consumption.

Methods: Records of 76 patients who underwent unilateral, cemented TKA were retrospectively reviewed.

Preoperative Anemia Independently Predicts 30-Day Complications After Aseptic and Septic Revision Total Joint Arthroplasty.

Background: Preoperative anemia is a common, important risk factor for adverse events after joint arthroplasty surgery. It affects 21%-35% patients undergoing total joint arthroplasty. To date, few studies have investigated the effect of preoperative anemia, specifically in revision total joint arthroplasty surgery.

Costs and Complications of Short Versus Long Cephalomedullary Nailing of OTA 31-A2 Proximal Femur Fractures in U.S. Veterans.

Objectives: In fractures without subtrochanteric extension, the indications for the use of short versus long cephalomedullary nails (CMNs) for intertrochanteric femur fractures are unclear. We hypothesized that long nails would be associated with higher costs and similar complication rates.

Design: Retrospective comparative study.

Promoting Endochondral Bone Repair Using Human Osteoarthritic Articular Chondrocytes.

Introduction: Current tissue engineering strategies to heal critical-size bone defects through direct bone formation are limited by incomplete integration of grafts with host bone and incomplete graft vascularization. An alternative strategy for bone regeneration is the use of cartilage grafts that form bone through endochondral ossification. Endochondral cartilages stimulate angiogenesis and are remodeled into bone, but are found in very small quantities in growth plates and healing fractures.

Complications of Morbid Obesity in Total Joint Arthroplasty: Risk Stratification Based on BMI.

This study stratifies complication risk in primary total joint arthroplasty (TJA) based on body mass index (BMI). Demographics, co-morbidities, perioperative variables, and complications were reviewed for 22,808 patients. Chi-squared, one-way ANOVA, univariate and multivariable regression analysis were performed.

Trophic stimulation of articular chondrocytes by late-passage mesenchymal stem cells in coculture.

Coculture of mesenchymal stem cells (MSCs) with articular chondrocytes (ACs) increases glycosaminoglycan (GAG) accumulation compared to monoculture. MSCs might (1) differentiate into ACs (progenitor role) and/or (2) stimulate AC matrix metabolism (trophic role). MSCs lose the ability to undergo chondrogenesis after extended passaging.

Mid-term outcomes in HIV-positive patients after primary total hip or knee arthroplasty.

We hypothesized that infection rates following total joint arthroplasty (TJA) in those with the human immunodeficiency virus (HIV) without hemophilia or drug use would be similar to rates in HIV-negative patients. Records at an urban HIV referral hospital were searched for patients who underwent primary total hip and knee arthroplasty from 2003 to 2010. The primary outcome was revision for infection.