Long-Term Participation after Mild Traumatic Brain Injury in Comparison to Orthopedic Trauma Controls: Results from a Longitudinal Multicenter Observational Cohort Study

A subgroup of patients shows incomplete recovery after mild traumatic brain injury (mTBI). Outcomes are commonly measured on the level of symptoms or functional recovery. An alternative way to study outcome after mTBI is to measure the level of participation. The objectives of this study were to examine (1) the level of participation in patients with mTBI at 12 months post-injury in comparison to a non-head injury orthopedic trauma control group; (2) the relationship between the outcome domains participation, functional outcome, and post-concussion symptoms. A prospective, longitudinal, multicenter cohort study was conducted. Participants were 140 adults with mTBI and 144 adults with minor (non-head) orthopedic injury. The following outcomes were measured: participation (Utrecht Scale for Evaluation and Rehabilitation-Participation: USER-P), functional outcome (Glasgow Outcome Scale Extended: (GOS-E), and post-concussion symptoms (Rivermead Post-Concussion Symptoms Questionnaire: RPQ). Adults with mTBI have a significantly lower objective participation level (USER-P Frequency scale) than controls. No differences were found between the groups on subjective participation (USER-P Restrictions and Satisfaction scales) nor on functional outcome (GOS-E). Fifty-three people with mTBI (38%) had a score of ≥2 on ≥3 items, while 26 (19%) had an unfavorable USER-P outcome (≥2 restrictions) and only 9 (6.5%) had an unfavorable GOS-E score (<7). In both groups, the presence of persistent symptoms led to a significantly unfavorable outcome on both the USER-P and GOS-E. Participation frequency is lower in mTBI than in orthopedic controls, mainly determined by a significantly lower number of hours of (un)paid work, education, and/or household activities. People with mTBI more often report post-concussion symptoms, but functional recovery is not different between the groups. Participation seems to better represent incomplete recovery than functional outcome, but future research should confirm these findings.