Acute Eye-Tracking Changes Correlated With Vestibular Symptom Provocation Following Mild Traumatic Brain Injury.

OBJECTIVES: To quantify norms and changes in eye-tracking proficiency, and determine vestibular symptom correlations in varsity college athletes following acute mild traumatic brain injury (mTBI). We hypothesized that mTBI impacts central coordination between the vestibular and oculomotor systems with resultant changes in eye-tracking proficiency that are correlated with vestibular symptom provocation. DESIGN: Retrospective cohort study. SETTING: Sports medicine care at a single institution. PATIENTS: One hundred and nineteen college athletes diagnosed with mTBI by a physician between 2013 and 2019. INTERVENTIONS: N/A. MAIN OUTCOME MEASURES: Standard deviation of tangential error, standard deviation of radian error, mean phase error, and horizontal gain from virtual reality-based, circular eye-tracking goggles used at baseline and within 72 hours post-mTBI. Headache, dizziness, nausea, and fogginess provocation after the Vestibular Ocular Motor Screening (VOMS) smooth pursuits subtest compared with pretest baseline, assessed within 72 hours post-mTBI. RESULTS: One hundred and nineteen college athletes (N = 56 women and 63 men) aged 18 to 24 years sustained a total of 177 mTBI. Forty-four percent of athletes displayed abnormal eye-tracking on at least 1 eye-tracking measure following acute mTBI compared with their baseline. From the VOMS, horizontal gain showed medium-sized to large-sized positive correlations with headache ( r = 0.34) and dizziness ( r = 0.54), respectively. Mean phase error showed a medium-sized negative correlation with nausea ( r = -0.32) on the VOMS. CONCLUSIONS: Eye-tracking proficiency was impaired and correlated with vestibular symptom provocation following acute mTBI in college athletes. Future research should examine eye-tracking proficiency testing in other acute care settings to support mTBI diagnosis.

Sex Differences in Common Measures of Concussion in College Athletes.

OBJECTIVE: Female athletes may be more likely to sustain a concussion and may vary in symptom presentation and neurocognitive impairments as compared with males. Scientific literature is limited by subjective assessments and underproportioned representation of women-the scope and etiology of sex-based differences are unknown. This study investigates sex-based differences in sports concussion assessments among college varsity athletes. DESIGN AND SETTING: Retrospective study of an institution's athletic head injury database. PARTICIPANTS: Acute postinjury and baseline data from 111 college athletes sustaining concussions between 2016 and 2018, diagnosed by a concussion specialist physician. MAIN OUTCOME MEASURES: Concussion assessments examined included the Sports Concussion Assessment Tool (SCAT5) and Vestibular Oculomotor Screening (VOMS) performed within 3 days (24-72 hours) of injury. RESULTS: No significant difference by sex was observed in the SCAT5 total symptom evaluation scores or severity scores, Standardized Assessment of Concussion, or Balance Error Scoring System ( P > .05) within 3 days of head injury. Females did report more "pressure in the head" severity scores from baseline to postconcussion (2.7 ± 1.5 increased symptomatology in females vs 1.8 ± 1.3 increase in males, P = .007). The VOMS test resulted in significant sex differences in smooth pursuit [0.6 ± 1.4 increase in females ( P < .001) vs 0.2 ± 0.6 increase in males ( P = .364)], horizontal saccades [0.6 ± 1.2 increase in females ( P < .001) vs 0.2 ± 0.5 increase in males ( P = .149)], and vertical saccades [0.9 ± 1.9 increase in females ( P < .001) vs 0.3 ± 0.7 increase in males ( P = .206)]. CONCLUSION: Our study did not show sex-based differences in baseline or acute postconcussive symptom reporting in most concussion assessment parameters, challenging previous research suggesting that females report more symptoms than males. Females did have significant differences in symptom provocation using the VOMS.

Smooth Pursuit Eye-Movement Abnormalities Associated With Cervical Spine Whiplash: A Scientific Review and Case Report.

Whiplash injuries may disrupt normal cervical afferent and efferent projections. Oculomotor abnormalities have been reported in chronic whiplash cases, but there is limited knowledge of their presence in acute whiplash and how acute assessment may target early intervention. We present a literature review and case study of a 22-year-old female presenting with an acute concussion and whiplash secondary to a high-speed motor vehicle collision. Smooth pursuit eye-movement abnormalities were observed in relative cervical rotation in the setting of clinical examination of cervicogenic dysfunction. Treatment was focused on cervical manual therapy. While concussive symptoms resolved after seven days, eye-tracking showed a mild improvement and continued to exist in relationship with cervicogenic dysfunction. After completing physical therapy twice weekly for two weeks and in-home exercises, clinical signs and symptoms of whiplash-associated cervicogenic dysfunction and abnormal smooth pursuit eye-movement resolved across all cervical positions. This case highlights the need for ocular-motor impairment assessment following acute whiplash, specifically during cervical rotation. Early intervention should focus on cervical manual therapy and may be important in supporting altered cervical afferents causing oculomotor dysfunctions following acute whiplash.

Energy Absorption Contribution and Strength in Female Athletes at Return to Sport After Anterior Cruciate Ligament Reconstruction: Comparison With Healthy Controls.

BACKGROUND: Female patients are more likely to suffer a second anterior cruciate ligament (ACL) injury after ACL reconstruction (ACLR) and return to sport (RTS) compared with healthy female controls. Few studies have examined the energy absorption contribution (EAC) that could lead to this subsequent injury. HYPOTHESIS: The ACLR group would demonstrate an altered EAC between joints (hip, knee, and ankle) but no difference in quadriceps, hip abduction, or hip external rotation (ER) strength at the time of RTS. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 34 female participants (ACLR: n = 17; control: n = 17) were enrolled in the study and matched for age and activity level. Jump landing performance for the initial 50 milliseconds of landing of a lateral-vertical jump was assessed using a 10-camera 3-dimensional motion capture system and 2 force plates. Isokinetic quadriceps strength was measured using a Biodex machine, and hip abduction and ER isometric strength were measured using a handheld dynamometer. All values were normalized to the participant's height and weight. A 1-way multivariate analysis of variance was used to assess between-group differences in the EAC at the hip, knee, and ankle. Two 1-way analyses of variance were used to independently examine quadriceps, hip abduction, and hip ER strength between the groups. RESULTS: Significant differences in the EAC were found between the groups for the involved hip (P = .002), uninvolved hip (P = .005), and involved ankle (P = .023). There were no between-group differences in the EAC for the involved or uninvolved knee or the uninvolved ankle. Patients who underwent ACLR demonstrated significantly decreased quadriceps strength on the involved limb (P = .02) and decreased hip ER strength on both the involved (P = .005) and uninvolved limbs (P = .002). No significant strength differences were found between the groups for the uninvolved quadriceps or for involved or uninvolved hip abduction. CONCLUSION: At RTS, patients who underwent ACLR utilized a greater hip EAC bilaterally and a decreased involved ankle EAC during a lateral-vertical jump. Furthermore, quadriceps strength on the involved limb and hip ER strength of bilateral lower extremities remained decreased. This could place greater stress on the ACL graft and ultimately lead to an increased injury risk.