Injuries Associated With Standing Electric Scooter Use

Key Points Question What are the types of injuries associated with standing electric scooter use and the characteristics and behaviors of injured patients? Findings In this study of a case series, 249 patients presented to the emergency department with injuries associated with electric scooter use during a 1-year period, with 10.8% of patients younger than 18 years and only 4.4% of riders documented to be wearing a helmet. The most common injuries were fractures (31.7%), head injuries (40.2%), and soft-tissue injuries (27.7%). Meaning In this study, injuries associated with electric scooter use were common, ranged in severity, and suggest low rates of adherence to existing regulations around rider age and low rates of helmet use.

First, all text fields in Database 2 (triage and provider notes) were replaced with lower case text.
Next, each note variable was combined into one "combined note" variable, which then contained all text from all notes during that encounter. Each "combined note" was searched for the presence of the following terms "bird", "lime", "scooter", "helmet", "protective", "electric", "motorcycle", "moped", "vespa", "non-motorized", "wheelchair", "segway", and "razor". Indicator variables were created for each term to facilitate manual review of the text entry data. Each x-ray order in Database 3 was placed into one of the following imaging categories: proximal upper extremity (shoulder, clavicle, scapula), proximal lower extremity (elbow, forearm, wrist, hand, finger), distal lower extremity (knee, tibia/fibula, ankle, foot), proximal lower extremity (hip, femur, pelvis), chest X-ray, and other. CTs of extremities (e.g. elbow CT) were placed into the above categories given they represented a similar clinical concern for fracture or injury of that portion of the body.
Each diagnosis in Database 4 was placed into categories based on ICD9. All encounters had ICD9 and ICD10 diagnoses provided; we chose to analyze ICD9 given greater experience of using them in the trauma literature. There were a small number of patient encounters (N=7) in which ICD10 codes did not automatically map to a specific ICD9 code; for these encounters, we manually cross-referenced and assigned the matching ICD9 code. eTable 1 provides the ICD9s used to generate the injury categories in Table 2.

Identification of cases
There were a total of 523 ED encounters with the terms "bird" "lime" or "scooter". We used automatic free-text searching through Stata 15.0 to create indicator variables. Thus, manual chart review was assisted by indicator variables and by highlighting of the relevant terms listed above.
An abstraction form was developed to capture determination of eligibility, reason for ineligibility if ineligible, described mechanism of traumatic event, documentation of helmet use, and documentation of intoxication. Two reviewers (TT and CL) split the cases in half and conducted manual chart review. Each reviewer piloted the initial abstraction form on 10 cases, and agreed on a final abstraction form. The two reviewers then independently reviewed the same 10 new cases, and agreed on eligibility and all other abstraction variables on all 10 of these cases.
For eligible cases, reviewers searched provider documentation for evidence of the use of a helmet (yes, no, unknown), documentation of evidence of intoxication in the history of present illness ("patient had been drinking alcohol", "patient admitted to being intoxicated", "patient smells of alcohol", etc.), and mechanism of accident (fall without additional details, scooter hit by moving vehicle, scooter hit a static object, pedestrian hit by scooter, pedestrian tripped over scooter, other). In many cases, the highlighted indicator variables made it immediately obvious that full chart review was not needed as the case could be excluded.
For a number of cases, it was clear that the encounter was for a standing electric scooter because the scooters were: 1) specifically referred to using an electric scooter company affiliation Bird or Lime (N=187) or 2) specifically referred to as "electric scooters" (N=69). All included cases met one of these two criteria.
In most excluded cases, it was obvious that the scooter was not the type of interest for this study and represented the sitting motorcycle scooters, electric mobility wheelchairs, or the nonmotorized scooters popularized by the company Razor® that have been available for years.
In 74 encounters, the term "scooter" was present, but it was unclear that the referenced scooters were the standing electric types. Because of the popularity of standing electric scooters and as many of these encounters were for patients aged 20-30, it is likely that at least some of these encounters were for standing electric scooter related injuries. However, these cases were not included in our results. eFigure 1 demonstrates the distribution of unclear cases and electric scooter cases by date over the one year study period.

Observational Study Methods
Four members of the research team observed the public common use patterns of standing electric scooter riders in two of the communities surrounding our hospitals (Santa Monica and Westwood, CA) for 7 hours between 9/8/2018 and 9/14/2018. The hours were chosen to include both weekday and weekend time periods and the intersections were chosen based on high use scooter areas previously observed in our communities. At a busy intersection in downtown Santa Monica, we stood at a corner and observed during a weekend afternoon between 2pm -5pm (Location A: Promenade) and on a weekday morning between 10 am -12pm (Location B: Promenade). At a similarly busy intersection on UCLA campus, we observed on a weekday morning between 11am -1pm (Location C: UCLA campus). Observers only counted riders traveling in one direction and avoided counting the same rider twice.
Prior to initial rental using either Bird or Lime, riders agree to be over 18 years of age, to wear a helmet, to not "double ride" and to follow local laws. We recorded the following five characteristics of electric scooter use: helmet use, riding on sidewalks, riding two people to one scooter, rider with a likely visual age < 13 years and adherence to traffic laws. Though sidewalk riding on an electric scooter is variably legal depending on the community, and in fact many communities do not currently have laws directly related to electronic scooters on sidewalks as