Personal mobility device-related injuries tied to more open fractures, longer hospital stay

Orthopaedic injuries associated with personal mobility devices (PMDs) are considered high-energy, with higher rates of open fractures, relative to bicycle injuries, according to a Singapore study, noting that PMD users are mostly younger and of economically viable age.

“PMD-related injuries were also associated with prolonged hospital stay and time off work,” the researchers said. “Caution should be exercised with PMD use, and the legislation limiting its speed limits and appropriate use should not go unheeded.”

Injury patterns were compared among PMD and bicycle users in this retrospective study of 140 patients admitted between November 2013 and September 2018. The following parameters were assessed: patients’ demographics (eg, age, gender, and body mass index), type of PMD, nature of injury, surgical intervention required, duration of hospitalization, and time off work.

Of the patients, 46 (32.9 percent) required treatment at the department of orthopaedic surgery: 19 were PMD users and 27 were bicycle riders. Majority of patients (n=16, 84.2 percent) with PMD-related injuries were men. PMD users were also significantly younger (mean age 45 years) than bicycle riders (mean age 56 years; p<0.05). [Singapore Med J 2021;doi:10.11622/smedj.2021050]

Five PMD users (26.3 percent) sustained open fractures, while 10 (52.6 percent) needed surgical intervention. In addition, two bicycle riders (7.4 percent) sustained open fractures and 19 (70.4 percent) required surgical intervention. Inpatient stay duration and time off work were similar in both groups.

“A striking finding in our study was that PMD-related injuries resulted in a higher proportion of open fractures when compared to bicycle use,” the researchers said. “The added soft tissue injuries sustained were indicative of higher energy injury.” [Indian J Orthop 2008;42:377-386; Injury 2012;43:891-897]

Looking at the mechanism of injuries, they found that PMD users either were traveling at high speeds or lacked control of the PMD at the time of the accident, thus not being able to slow down enough to prevent the mishap. Four of the five patients with open fractures in the PMD group had injuries involving the upper limb, indicating that these users attempted to break their fall.

Of note, there is substantial healthcare cost and economic burden associated with injuries among PMD users, according to the researchers. The growing number of PMD users makes it a valid cause for concern. [https://www.cpsc.gov/content/motorized-scooter-useincreases-and-injuries-climb]

“Despite comparable hospital stay and time away from work between the two patient groups, the time away from the workforce was nevertheless considerable,” the researchers said. “Regulators thus should strive to find a balance between policies restricting this novel mode of transport and ensuring the safety of PMD riders and the public at large.”

Further research involving multiple centres and a larger sample is warranted to improve understanding of PMD-related injuries, the researchers noted. They also recommend the establishment of a national trauma registry for PMDs and e-bikes to facilitate future prospective studies.

In addition to the nature and mechanism of injury, its complications, intervention performed, duration of hospitalization, time off work, and use of protective gear, important parameters for recording among patients sustaining related injuries must include basic demographic data. [Injury 2017;48:2140-2144]

“Last but not the least, we suggest a standardization of the definition for what qualifies as a PMD within the literature, so as to facilitate future reviews,” the researchers said. “This is particularly pertinent as some roadworthy e-bikes capable of achieving significantly greater speeds may present with a different spectrum of injuries.”