# MaTrICS: Micromobility Associated With Trauma and Its Clinical and Socioeconomic Impact

## TL;DR

This study examines the clinical and economic impact of micromobility-related trauma in Portugal, highlighting the need for preventive measures.

## Contribution

The study provides the first detailed analysis of micromobility trauma in a Portuguese hospital setting, emphasizing risk behaviors and economic costs.

## Key findings

- Most accidents involved electric scooters and single-vehicle crashes.
- Low helmet use and alcohol consumption were linked to increased injury severity.
- Severe trauma cases had significant clinical and economic impacts despite overall minor injuries.

## Abstract

Micromobility includes lightweight vehicles, such as bicycles and electric scooters, with limited speed and weight, and is promoted as a sustainable alternative for urban transport. Its expansion has been accompanied by a significant rise in accidents, particularly among users without helmets or under the influence of alcohol. In Portugal, despite growing adherence, data on the clinical and economic impact of micromobility remain scarce. This study aims to characterise the morbidity, severity, and associated costs of these accidents in a Portuguese tertiary hospital between 2019 and 2022.

A retrospective observational study was conducted at Unidade Local de Saúde de São José, including adult patients with trauma related to micromobility vehicles between January 2019 and December 2022. Data were retrieved from hospital clinical records. Drivers or occupants of motorcycles were excluded. Statistical analysis was performed using IBM SPSS® (IBM Corp., Armonk, NY), applying the Mann-Whitney test (p < 0.05).

A total of 1,566 patients with micromobility-related trauma were included, mostly from single-vehicle incidents (n = 1,379; 88.1%) and involving electric scooters (n = 1,015; 64.8%). The mean age was 50 years, and 677 patients (43.2%) were Portuguese nationals. Helmet use was reported in only 21 of 302 cases with available data (7%). The most frequent injuries affected the limbs (n = 1,000; 63.8%) and the head (n = 718; 36.9%), with a mean Injury Severity Score (ISS) of 2.7. Sixteen cases (1.0%) were classified as severe (ISS ≥ 16). Alcohol consumption was significantly associated with greater severity (p = 0.009). A total of 271 patients (17.3%) were hospitalised, 18 of whom (1.1%) required intensive care. The estimated total cost of hospitalisation was €456,000. There were five in-hospital deaths (0.3%) and 34 cases (2.2%) of persistent neurological sequelae.

Most micromobility accidents involved scooters and resulted from single-vehicle crashes, reflecting patterns similar to those reported internationally. Risk behaviours, such as low helmet use and alcohol consumption, were identified, the latter being associated with increased injury severity. Although minor injuries predominated, a subgroup sustained severe trauma with significant clinical, functional, and economic impact. These findings highlight the need for preventive strategies and standardised registries to support effective monitoring and the implementation of targeted public health measures.

Although minor injuries were most frequent, a minority of cases involved severe trauma with relevant clinical and economic impact. The findings support the need for preventive measures and prospective data collection systems to inform effective public policies.