Abstract:
Context: Medical organizations recommend a battery of tests for concussion assessment that typically include measures of cognitive function, postural control, and self-report symptoms. Symptom reports commonly include items related to balance and memory, but it is unclear if concussed athletes are able to accurately identify the presence or absence of these symptoms. Objective: To elucidate the relationship between subjective symptom reports and objective measures of postural control and cognitive functioning. We hypothesized that strong relationships would exist between symptom reports of impaired postural control and dynamic posturography and symptom reports of impaired memory and computer-based cognitive testing. Design and Setting: This longitudinal investigation was completed in a University research laboratory. Patients: College athletes (N=32, 75% male, 19.7+1.2 years with a diagnosed concussion. Interventions: All individuals received a baseline and post-morbid assessment (within 48 hour of diagnosis) for postural control with the NeuroCom Sensory Organization Test (SOT) and cognitive functioning and symptom reports with the ImPACT. Main Outcome Measures: Spearman’s correlations were calculated between Likert scores for the post-injury balance symptoms of “dizziness” and “balance problems” and the SOT output change scores for composite balance, visual ratio, vestibular ratio, and somatosensory ratio. Separate correlation coefficients were completed for the cognitive symptoms of “feeling mentally foggy,” “difficulty concentrating,” and “difficulty remembering” with the change in ImPACT output variables of verbal memory, visual memory, processing speed, and reaction time. Results: Balance related symptoms were reported in 39% of the sample and cognitive symptoms in 59%. Spearman correlation calculations between the self-report balance symptom of “dizziness” and SOT composite balance (rs=-.55, p<.00) and the vestibular ratio (rs=.50, p=.01) were significant. Reports of “balance problems” were significantly correlated with change scores of composite balance (rs=-.52, p<.00), somatosensory ratio (rs=-.41, p=.03), visual ratio (rs=-.39, p=.04), and the vestibular ratio (rs=.57, p<.00). The correlation calculations between the cognitive symptom of “feeling mentally foggy” and the changes scores of the ImPACT output variables were significant with reaction time (rs=-.36, p=.03). Significant correlations were also noted between “difficulty concentrating” and composite verbal memory score (rs=-.41, p=.01) and “difficultly remembering” with the composite verbal memory score (rs=-.48, p<.00) and reaction time (rs=-.36, p=.03). Conclusions: Each aspect of the concussion assessment supplies the clinician with unique information that can be used in conjunction with the clinical exam. These results suggest that athletes are able to self-identify some deficits to postural control and cognitive functioning following a concussive event. Clinicians solely relying on symptom reports for diagnostic purposes are encouraged broaden their assessment protocol to encompass other measures that athletes may not adequately recognize.