Clinical Changes in Cervical Neuromuscular Control Following Subconcussive Impacts

The Diagnostic Utility of Cervical Spine Proprioception for Adolescent Concussion

OBJECTIVE

Cervical spine proprioception may be impaired after concussion. Our objective was to determine the diagnostic utility of cervical spine proprioception for adolescent concussion.

DESIGN

Cross-sectional.

SETTING

Research laboratory.

PARTICIPANTS

Adolescents ≤18 days of concussion and uninjured controls.

INTERVENTIONS

N/A.

MAIN OUTCOMES

Head repositioning accuracy (HRA) testing, a measure of cervical spine proprioception. The HRA test involved patients relocating their head back to a neutral starting position with eyes closed after maximal cervical spine flexion, extension, and right and left rotations. The overall HRA error score was the mean error (distance from the starting point to self-reported return to neutral) across 12 trials: 3 trials in each direction. We used t-tests to compare group means and logistic regression (outcome = group, predictor = HRA, covariates) to calculate odds ratios. We used a receiver operator characteristic curve to evaluate area under the curve (AUC) and calculate the optimal HRA cutpoint to distinguish concussion from controls.

RESULTS

We enrolled and tested 46 participants with concussion (age = 15.8 ± 1.3 years, 59% female, mean = 11.3 ± 3.3 days postconcussion) and 83 uninjured controls (age = 16.1 ± 1.4 years, 88% female). The concussion group had significantly worse HRA than controls (4.3 ± 1.6 vs 2.9 ± 0.7 degrees, P < 0.001, Cohen d = 1.19). The univariable HRA model AUC was 0.81 (95% CI = 0.73, 0.90). After adjusting for age, sex, and concussion history, the multivariable model AUC improved to 0.85 (95% CI = 0.77, 0.92). The model correctly classified 80% of participants as concussion/control at a 3.5-degree cutpoint.

CONCLUSIONS

Adolescents with concussion demonstrated worse cervical spine proprioception than uninjured controls. Head repositioning accuracy may offer diagnostic utility for subacute concussion.

Deficits in neurocognitive performance in patients with chronic ankle instability during a neurocognitive balance task - A retrospective case-control study

OBJECTIVES

To assess the neurocognitive performance while maintaining balance of patients experiencing CAI compared to healthy controls. In patients with CAI, the affected limb was also compared to the contralateral limb.

DESIGN

A retrospective case-control study.

SETTING

Laboratory study.

PARTICIPANTS

We included 27 patients with CAI and 21 healthy controls.

METHODS

The study consisted of two sessions, namely familiarisation and experimentation, which were scheduled with a gap of at least one week between them. During the experimental trial, both groups performed the Y-Balance Test and Reactive Balance Test once on each limb.

MAIN OUTCOME MEASURES

The main outcome measures are accuracy and visuomotor response time (VMRT) calculated via video-analysis and with the Fitlight™-hardware and software respectively during the Reactive Balance Test (RBT).

RESULTS

No data was excluded from the final analysis. Patients with CAI exhibited significantly lower accuracy than healthy controls, with a mean difference of 8.7% (±3.0)%. There were no differences for VMRT between groups. Additionally, no significant differences were observed between the affected and contralateral limb of the patient group for both accuracy and VMRT.

CONCLUSIONS

Patients with CAI showed lower accuracy, but similar VMRT compared to healthy controls during a neurocognitive balance task, indicating impaired neurocognitive function. Patients exhibit comparable speed to healthy individuals when completing neurocognitive balance tasks, yet they display a higher frequency of accuracy errors in accurately perceiving their environment and making decisions under time constraints. Future research should gain more insights in which other cognitive domains are affected in patients with CAI for a better grasp of this condition's underlying mechanism.

The association between contact sport exposure and cervical sensorimotor dysfunction: a scoping review of implications for future musculoskeletal injury risk

BACKGROUND

While morphological changes to the cervical spine have been observed for over 40 years in response to contact sport participation, little is known about the secondary effects of the cervical impairment on future musculoskeletal injury and disability.

OBJECTIVES AND DESIGN

A scoping review was performed to discuss the relationship between contact sport participation and morphological changes to the cervical spine. Moreover, the correlation between morphological changes in the musculoskeletal structures of the cervical spine and resultant deficits in cervical sensorimotor and neuromotor function are discussed. Lastly, how alterations in cervical sensorimotor function may affect overall risk of musculoskeletal injury is discussed.

METHODS

The scientific literature was searched in PubMed, Sport Discus, and Web of Science pertaining to contact-sport athletes and/or cervical pathology and the cervicocephalic network. The Asksey and O'Malley's framework and PRISMA for Scoping Reviews were used to conduct and report the following review. Included articles were grouped into three categories: (1) Morphological changes to the cervical spine in contact sport athletes. (2) The role of the neuromotor pathways of the cervical spine in maintenance of postural tone and coordination of the extremities. (3) The correlation between altered cervical sensorimotor function and a resultant increase in musculoskeletal injury risk.

RESULTS

Our search identified 566 documents, of which 405 underwent full-text screening, resulting in 54 eligible studies for the review. Widespread cervical sensorimotor dysfunction was observed in contact sport athletes. Independently, cervical sensorimotor function was demonstrated to play a critical role in postural control and limb coordination. However, limited research exists exploring the interaction between contact sport participation and altered cervical sensorimotor function, as well as an associated increase in musculoskeletal injury risk.

CONCLUSIONS

Limited evidence exists linking cervical injury and/or observed deficits in cervical sensorimotor and neuromotor function to musculoskeletal injury risk. Longitudinal studies combining imaging measures (e.g., MRI, DEXA), cervical functional test, and prospective injury risk are needed to further explore the correlation between resultant cervical sensorimotor deficits following contact sport impacts and future musculoskeletal injury risk.