Background: For the vast majority of displaced femoral neck fractures in older patients, cemented femoral fixation is indicated because it is associated with a lower risk of periprosthetic fracture than cementless fixation. Nevertheless, cementless fixation continues to be utilized with high frequency for hip fractures in the United States. It is therefore helpful to understand the performance of individual cementless brands and models. Although prior studies have compared femoral stems by design type or stem geometry, there may still be a difference in revision risk according to femoral stem brand given the potential differences within design groupings with regard to manufacturing, implantation systems, and implant design nuances among vendors.
Questions/purposes: (1) Is there a difference in aseptic revision risk among femoral stem brands in patients ≥ 60 years of age who have displaced femoral neck fractures treated with cementless hemiarthroplasty? (2) Is there a difference in revision for periprosthetic fracture among femoral stem brands in patients ≥ 60 years of age with displaced femoral neck fractures treated with cementless hemiarthroplasty?
Methods: A retrospective, comparative, large-database cohort study was conducted using data from Kaiser Permanente's Hip Fracture Registry. This integrated healthcare system covers more than 12 million members throughout eight regions in the United States; membership has been found to be representative of the general population in the areas served. The Hip Fracture Registry collects details on all patients who undergo hip fracture repair within the organization. These patients are then longitudinally monitored for outcomes after their repair, and all identified outcomes are manually validated through chart review. Patients ages ≥ 60 years who underwent unilateral hemiarthroplasty treatment of a displaced femoral neck fracture from 2009 to 2021 were identified (n = 22,248). Hemiarthroplasties for polytrauma, pathologic or open fractures, or patients who had additional surgeries at other body sites during the same stay, as well as those with prior procedures in the same hip, were excluded (21.4% [4768]). Cemented procedures and those with missing or inconsistent implant information (for example, cement used but cementless implant recorded) were further excluded (47.1% [10,485]). To allow for enough events for evaluation, the study sample was restricted to seven stems for which there were at least 300 hemiarthroplasties performed, including four models from DePuy Synthes (Corail®, Summit®, Summit Basic, and Tri-Lock®) and three from Zimmer Biomet (Medial-Lateral [M/L] Taper®, Trabecular Metal®, and Versys® Low Demand Fracture [LD/FX]). The final sample included 5676 cementless hemiarthroplasties: 653 Corail, 402 M/L Taper, 1699 Summit, 1590 Summit Basic, 384 Tri-Lock, 637 Trabecular Metal, and 311 Versys LD/FX. Procedures were performed b
Background: There is continuing debate about the ideal philosophy for component alignment in TKA. However, there are limited long-term functional and radiographic data on randomized comparisons of kinematic alignment versus mechanical alignment.
Questions/purposes: We present the 10-year follow-up findings of a single-center, multisurgeon randomized controlled trial (RCT) comparing these two alignment philosophies in terms of the following questions: (1) Is there a difference in PROM scores? (2) Is there a difference in survivorship free from revision or reoperation for any cause? (3) Is there a difference in survivorship free from radiographic loosening?
Methods: Ninety-nine patients undergoing primary TKA for osteoarthritis were randomized to either the mechanical alignment (n = 50) or kinematic alignment (n = 49) group. Eligibility for the study was patients undergoing unilateral TKA for osteoarthritis who were suitable for a cruciate-retaining TKA and could undergo MRI. Patients who had previous osteotomy, coronal alignment > 15° from neutral, a fixed flexion deformity > 15°, or instability whereby constrained components were being considered were excluded. Computer navigation was used in the mechanical alignment group, and patient-specific cutting blocks were used in the kinematic alignment group. At 10 years, 86% (43) of the patients in the mechanical alignment group and 80% (39) in the kinematic alignment group were available for follow-up performed as a per-protocol analysis. The PROMs that we assessed included the Knee Society Score, Oxford Knee Score, WOMAC, Forgotten Joint Score, and EuroQol 5-Dimension score. Kaplan-Meier analysis was used to assess survivorship free from reoperation (any reason) and revision (change or addition of any component). A single blinded observer assessed radiographs for signs of aseptic loosening (as defined by the presence of progressive radiolucent lines in two or more zones), which was reported as survivorship free from loosening.
Results: At 10 years, there was no difference in any PROM score measured between the groups. Ten-year survivorship free from revision (components removed or added) likewise did not differ between the groups (96% [95% CI 91% to 99%] for the mechanical alignment group and 91% [95% CI 83% to 99%] for the kinematic alignment group; p = 0.38). There were two revisions in the mechanical alignment group (periprosthetic fracture, deep infection) and four in the kinematic alignment group (two secondary patella resurfacings, two deep infections). There was no statistically significant difference in reoperations for any cause between the two groups. There was no difference with regard to survivorship free from loosening on radiographic review (χ2 = 1.3; p = 0.52) (progressive radiolucent lines seen at 10 years were 0% for mechanical alignment and 3% for kinematic alignment).
Conclusion:
Background: Electric scooters (e-scooters) have become a widely adopted form of transportation. Information regarding the timing, conditions, and context associated with increased frequency of e-scooter-related injuries could inform policy that may potentially reduce associated injuries and healthcare costs. However, this information is lacking, as most research to date has focused on the injury patterns sustained while using e-scooters rather than context. We sought to evaluate these factors in an urban setting and describe how these are evolving over time, as such information may help guide future safety initiatives.
Questions/purposes: (1) How has the epidemiology of e-scooter-related injuries in Denver, CO, USA, changed over time? (2) What are the associated hospital charges to treat patients with these injuries? (3) What circumstances are associated with an increased frequency of e-scooter-related injuries and higher accompanying hospital charges?
Methods: A retrospective study at a Level 1 trauma center in Denver, CO, USA, examined trends in e-scooter-related injuries from January 1, 2020, to November 1, 2023. Patients were identified by the key terms "e-scooter crash" or "scooter" within their emergency department/urgent care visit notes. Patient demographic and injury characteristics and hospital data (admission and hospital charges) were analyzed. Patients who sustained injuries from devices other than stand-up e-scooters or who did not have complete records available for analysis were excluded. The epidemiologic data on e-scooter-related injuries were quantified for each year within the study period, and descriptive analyses were performed to assess patient and injury characteristics, including age, gender, and fracture characteristics. Hospital charges were calculated using the mean annual sum of hospital charges associated with the treatment for e-scooter-related injuries. Circumstances influencing the frequency of injury and magnitude of hospital charges were assessed based on the timing of presentation to the emergency department or urgent care. We recognize that charge may have little or no direct relationship to true cost, but we believe that within one hospital system it represents a reasonable metric for comparative resource utilization. Injury frequency by time of the day and day of the week were compared using chi-square goodness-of-fit analyses. The value of hospital charges associated with e-scooter-related injuries was compared between patients presenting with alcohol intoxication and those who were not intoxicated.
Results: In all, 2424 patients were identified as having e-scooter-related injuries (58% [1405] men, 42% [1019] women, median (IQR) age 30 years [25 to 37 years]). The number of annual e-scooter-related injuries during the years 2020 to 2023 were 273 in 2020, 736 in 2021, 758 in 2022, and 657 in 2023 (only 10 months). From 2