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Highly cross-linked polyethylene (HXLPE) has become the preferred bearing surface in total hip arthroplasty. However, its acceptance in total knee arthroplasty (TKA) has not been as robust because of concerns pertaining to wear and its impact on implant failure. Therefore, this multicenter study was purposed to evaluate the 10-year (1) radiographic outcomes; (2) complications; and (3) implant survivorship in patients with TKA receiving a sequentially irradiated and annealed HXLPE. A retrospective, multi-center study was performed on 139 patients (171 TKAs) who underwent primary TKA with HXLPE and possessed a minimum of 10-year follow-up. Radiographs were analyzed for radiolucencies along the implant-fixation interface using the Modern Knee Society Radiographic Evaluation System. Kaplan-Meier analysis determined implant survivorship when the end points were revision for polyethylene wear and polyethylene revision for any reason. Sixteen TKAs (9.9%) demonstrated periprosthetic linear radio-lucencies. Seventeen TKAs (9.9%) required additional surgeries, 9 (5.3%) of which were revisions, with 1 (0.6%) TKA requiring revision because of polyethylene wear. Other causes of revision included instability (1.8%), infection (1.6%), and arthrofibrosis (1.6%). The mean time to revision was 5.9 years (range, 0.1–11.1 years). Survivorship pertaining to polyethylene revision for wear was 99.4%, whereas all-cause polyethylene revision was 94.7%. This study in patients undergoing primary TKA using a second-generation HXLPE demonstrated excellent results with respect to polyethylene wear characteristics and strength with a 99.4% survivorship at 10 years. [ Orthopedics . 2023;46(2):e111–e117.]

Recently, 3-dimensional (3D) printing technology has been used in the development of titanium metaphyseal cones to manage severe bone loss in revision total knee arthroplasty (rTKA). This study assessed (1) radiographs; (2) functional outcomes; (3) complications; and (4) 2-year implant survivorship in patients receiving 3D-printed titanium metaphyseal cones for moderate-to-severe tibial and femoral bone loss in rTKA. A single institution, retrospective chart review was performed for patients with large bone defects treated with a 3D-printed femoral or tibial titanium metaphyseal cone between 2015 and 2017 during rTKA (N=54). Paired sample t tests analyzed Knee Society Scores (KSS). Kaplan–Meier analyses determined implant survivorship when the endpoint was cone revision for aseptic loosening, cone revision for any reason, and reoperation for any reason. The authors found that 51 (98.1%) of 52 available radiographs demonstrated well-fixed components without any evidence of loosening or migration. Mean postoperative KSS scores were significantly higher when compared with preoperative scores (80.4 vs 52.0; P >.001). One patient experienced aseptic loosening of their cone. Seven additional cones were explanted as a consequence of reinfection, 1 of which was removed prior to arthrodesis. Cone survivorship was 98.5% when the endpoint was cone revision due to aseptic loosening, 88.2% when cone revision was due to any reason, and 77.9% for any reoperation. Metaphyseal cones appear to be well-suited for large bone defects during rTKA and the authors' findings suggest that cones may be a viable option for metaphyseal fixation during rTKA. Future studies should focus on their durability during a longer time period. [ Orthopedics . 2021;44(1):43–47.]

Few studies have investigated nationwide patient trends and health care costs for reverse shoulder arthroplasty (RSA) after 2014. This study uses a large validated nationwide database to retrospectively assess changes in patient and hospital demographic features, hospital costs, and hospital charges for inpatient RSA procedures before and after implementation of the Affordable Care Act. The National Inpatient Sample database was used to identify all patients who underwent RSA between January 2011 and December 2015, yielding 163,171 patients (63.4% female; mean age, 72 years). Categorical data were assessed with chi-square/Fisher's exact test, and continuous data were assessed with analysis of variance. There was an increased proportion of RSA recipients identifying as Hispanic (4.1% to 4.8%) and Native American (0.1% to 0.4%; P P P =.002), whereas an increase occurred in hospital charges (+$6,314; P Orthopedics . 2022;45(2):97–102.]

In 2014, Maryland implemented an experimental reimbursement model, Global Budget Revenue (GBR). This model provided hospitals with a capitated annual budget each fiscal year to use toward all services, regardless of payer. Goals of GBR include reductions in cost, improvements in care quality, and increased access for patients to high-volume procedures, such as total knee arthroplasty (TKA). We assessed demographics and outcomes among patients with low incomes and patients of racial minority groups in Maryland who underwent TKA before and after GBR implementation. Patients undergoing TKAs from 2011 to 2016 were queried from the Maryland State Inpatient Database, resulting in 71,066 patients. There were 13,722 patients with low incomes and 19,846 patients of racial minority groups. The chi-square test was used for sex, income, insurance, Charlson Comorbidity Index, and morbid obesity, with the Student's t test being reserved for age before and after GBR. The proportion of patients with low incomes decreased the year before GBR but increased with GBR and maintained ( P P P P P Orthopedics . 2022;45(1):e11–e16.]

Same-day bilateral total knee arthroplasties (SBTKAs) are associated with shorter rehabilitation and lower cost. However, controversy surrounding the safety of SBTKAs exists. Recent studies are lacking to determine whether patient selection has brought SBTKA in line with unilateral total knee arthroplasty (UTKA). Therefore, the authors evaluated and compared patient characteristics, hospital characteristics, and inpatient course between UTKA and SBTKA from 2009 to 2016. The National Inpatient Sample was queried from 2009 to 2016 for UTKA and SBTKA patients. Of the 5,329,466 patients identified, 5,084,328 (95.4%) patients received UTKAs and 245,138 (4.6%) patients underwent SBTKAs. Incidence, rate, patient and hospital characteristics, health status, length of stay (LOS), discharge disposition, hospital charges, hospital costs, and complications were analyzed and statistically compared. The incidence (−1.4%) and rate (15.8%) of SBTKAs decreased (both P P P P Orthopedics . 2021;44(3):e407–e413.]

Maryland implemented the all-payer, rater-setting Global Budget Revenue (GBR) payment model in 2014 to reduce cost and improve quality. This study assessed the effect of GBR on total knee arthroplasty (TKA) outcomes by sex. Specifically, the authors assessed (1) demographics and (2) outcomes of males and females undergoing TKA before and after GBR implementation. The Maryland State Inpatient Database was queried from 2011 to 2016. There were 71,066 TKAs (male, n=25,413; female, n=45,634). For continuous and categorical variables, t testing and chi-square analyses were used, respectively. Difference-in-difference analyses using multiple regression compared changes in sex from the pre-GBR period (2011-2013) with the post-GBR period (2014–2016). The female proportion decreased (−1.9%; P =.040). Proportionally more TKA patients were Hispanic and Asian, from high-income areas, using Medicare and Medicaid, and morbidly obese (all P P P P P Orthopedics . 2021;44(2):e266–e273.]