Examining the Sensitivity of the 2023 American Congress of Rehabilitation Medicine's Diagnostic Criteria for Mild Traumatic Brain Injury Using a Sport-Related Concussion Sample.

Objective: To (1) retrospectively apply the updated American Congress of Rehabilitation Medicine (ACRM) mild traumatic brain injury (mTBI) criteria to a cohort of high school athletes previously diagnosed with sport-related concussion (SRC) using prior clinical definitions, and (2) compare demographics, medical history, and recovery outcomes between those who met the full mTBI criteria versus those classified as suspected mTBI.

Setting: Outpatient Specialty Concussion Clinic.

Participants: In total, 181 concussed athletes aged 14 to 18 years were presented to clinic within 72 hours of injury. All were diagnosed with SRC by a certified athletic trainer or physician using the Concussion in Sport Group definition, which defines SRC as any traumatic blow to the head/body causing neurologic symptoms.

Design: Retrospective cohort study.

Main measures: Participants were classified as having a full or suspected mTBI based on the ACRM 2023 criteria. Full mTBIs required: (1) a plausible mechanism and either (2a) a clinical sign (eg, amnesia, loss of consciousness), or (2b) at least 2 symptoms plus a clinical examination finding. Suspected mTBIs had a plausible mechanism and at least 2 symptoms or at least 2 examination findings. Groups were compared across demographics, medical history, and recovery metrics (return-to-learn, symptom resolution, return-to-play).

Results: Of the 181 patients (mean age 16.3 ± 1.3 years; 35.9% female), 114 (63.0%) met the definition for a full mTBI, whereas 67 (37.0%) had a suspected mTBI. Significant differences included higher rates of family migraine history (24.8% vs 7.7%, P = .019) and on-field evaluations (50.4% vs 38.5%, P < .001) in the full group. No significant differences in return-to-learn (median [Mdn]: 4.0 vs 3.0), symptom resolution (Mdn: 11.0 vs 12.5), or return-to-play (Mdn: 15.0 vs 14.5) were noted (P > .05).

Conclusion: Among high school athletes with SRC, most met the updated full ACRM mTBI criteria, with the rest meeting the suspected mTBI criteria. Results suggest high sensitivity for the ACRM definition for diverse concussion presentations.