BACKGROUND: To determine the frequency, characteristics, and use of resources related to electric scooter (e-scooter) injuries in the emergency department (ED) of a major metropolitan area hospital. METHODS: We performed a retrospective review of all ED presentations related to e-scooter injuries at a level I trauma center between May 2017 and February 2020. We identified ED presentation data, injury-related data, patients’ clinical course after evaluation, injury diagnosis, surgical procedures, and ED readmissions. RESULTS: A total of 3,331 patients with e-scooter injuries presented to the ED over a 34-month period. There was a 6-fold increase in e-scooter-related injuries presenting to the ED, from an average of 26.9 injuries per month before the introduction of shared e-scooter services in August 2018 to an average of 152.6 injuries per month after its introduction. The average injury rate during weekdays was 3.27 per day, with the majority of injuries occurring in the afternoon. The most common mechanism of injury was rider fall (79.1%). There were a total of 2,637 orthopedic injuries, of which 599 (22.7%) were fractures. A total of 296 (8.9%) patients were hospitalized following the initial ED admission, and 462 surgeries were performed within 7 days of ED arrival. CONCLUSIONS: The introduction of the shared e-scooter services is associated with a dramatic increase in e-scooter injuries presenting to the ED. E-scooter use carries considerably underestimated injury risks of high-energy trauma and misunderstood mechanisms of injuries. These injuries challenge the healthcare system, with a major impact on both EDs and surgical departments.

Background: Bicruciate-stabilized (BCS) total knee arthroplasty (TKA) aims to restore normal kinematics by replicating the function of both cruciate ligaments. Conventional cruciate-retaining (CR) design in TKA has shown previous clinical success with lower complication rates. This study compared the patient-reported outcomes between the BCS and CR TKA designs. Methods: This retrospective study examined patients who underwent primary TKA using a CR or a BCS implant. Patient demographics, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR), and Forgotten Joint Score (FJS) were compared between two cohorts. Patient-reported outcome measures were analyzed using independent samples t-tests. Results: There were no significant preoperative demographic differences between groups. The CR cohort (n = 756) had significantly higher average KOOS, JR Scores compared to the BCS cohort (n = 652) at 3 months (59.7 ± 3.8 vs. 53.0 ± 3.9, p < 0.001) and 2 years (62.6 ± 8.0 vs. 53.8 ± 6.7, p = 0.001) after TKA. Within the cohort, KOOS, JR delta differences were not significant for CR when comparing patient scores 3 months to 1 year after surgery. Meanwhile, the BCS patients did show significant delta improvement (4.1 ± 1.9, p = 0.030) when compared 3 months to 1 year after surgery. One year postoperatively, the BCS cohort (n = 134) showed a significantly higher average FJS score (49.5 ± 31.4, vs. 36.8 ± 28.5, p = 0.028) than the CR cohort (n = 203). Both cohorts displayed a significant difference in delta improvements within their respective cohort when measuring FJS from 3 months to 1 year, 2 years, and 3 years after surgery. Conclusions The CR cohort performed better on average, compared to the BCS cohort in measures of KOOS, JR scores at the 2-year follow-up. The BCS cohort performed marginally better regarding FJS only at 1-year follow-up.