The Role of Neck Musculature in Traumatic Brain Injuries in Older Adults: Implications From Sports Medicine

Association Between Frailty and Head Impact Location After Ground-Level Fall in Older Adults

BACKGROUND

Mild traumatic brain injuries (TBIs) are highly prevalent in older adults, and ground-level falls are the most frequent mechanism of injury.

OBJECTIVE

This study aimed to assess whether frailty was associated with head impact location among older patients who sustained a ground-level fall-related, mild TBI. The secondary objective was to measure the association between frailty and intracranial hemorrhages.

METHODS

We conducted a planned sub-analysis of a prospective observational study in two urban university-affiliated emergency departments (EDs). Patients 65 years and older who sustained a ground-level fall-related, mild TBI were included if they consulted in the ED between January 2019 and June 2019. Frailty was assessed using the Clinical Frailty Scale (CFS). Patients were stratified into the following three groups: robust (CFS score 1-3), vulnerable-frail (CFS score 4-6), and severely frail (CFS score 7-9).

RESULTS

A total of 335 patients were included; mean ± SD age was 86.9 ± 8.1 years. In multivariable analysis, frontal impact was significantly increased in severely frail patients compared with robust patients (odds ratio [OR] 4.8 [95% CI 1.4-16.8]; p = 0.01). Intracranial hemorrhages were found in 6.2%, 7.5%, and 13.3% of robust, vulnerable-frail, and severely frail patients, respectively. The OR of intracranial hemorrhages was 1.24 (95% CI 0.44-3.45; p = 0.68) in vulnerable-frail patients and 2.34 (95% CI 0.41-13.6; p = 0.34) in those considered severely frail.

CONCLUSIONS

This study found an association between the level of frailty and the head impact location in older patients who sustained a ground-level fall. Our results suggest that head impact location after a fall can help physicians identify frail patients. Although not statistically significant, the prevalence of intracranial hemorrhage seems to increase with the level of frailty.

Head and Neck Characteristics as Risk Factors For and Protective Factors Against Mild Traumatic Brain Injury in Military and Sporting Populations: A Systematic Review

BACKGROUND

Investigators have proposed that various physical head and neck characteristics, such as neck strength and head and neck size, are associated with protection from mild traumatic brain injury (mTBI/concussion).

OBJECTIVES

To systematically review the literature and investigate potential relationships between physical head and neck characteristics and mTBI risk in athletic and military populations.

METHODS

A comprehensive search of seven databases was conducted: MEDLINE, EMBASE, CINAHL, Scopus, SPORTDiscus, Cochrane Library, and Web of Science. Potential studies were systematically screened and reviewed. Studies on military and athletic cohorts were included if they assessed the relationship between physical head-neck characteristics and mTBI risk or proxy risk measures such as head impact kinematics.

RESULTS

The systematic search yielded a total of 11,723 original records. From these, 22 studies met our inclusion criteria (10 longitudinal, 12 cross-sectional). Relevant to our PECO (Population, Exposure, Comparator, and Outcomes) question, exposures included mTBI incidence and head impact kinematics (acceleration, velocity, displacement) for impacts during sport play and training and in controlled laboratory conditions. Outcome characteristics included head and neck size (circumference, mass, length, ratios between these measures), neck strength and endurance, and rate of force development of neck muscles.

DISCUSSION

We found mixed evidence for head and neck characteristics acting as risk factors for and protective factors against mTBI and increased susceptibility to head impacts. Head-neck strength and size variables were at times associated with protection against mTBI incidence and reduced impact kinematics (14/22 studies found one or more head-neck variable to be associated with protection); however, some studies did not find these relationships (8/22 studies found no significant associations or relationships). Interestingly, two studies found stronger and larger athletes were more at risk of sustaining high impacts during sport. Strength and size metrics may have some predictive power, but impact mitigation seems to be influenced by many other variables, such as behaviour, sex, and impact anticipation. A meta-analysis could not be performed due to heterogeneity in study design and reporting.

CONCLUSION

There is mixed evidence in the literature for the protective capacity of head and neck characteristics. We suggest field-based mTBI research in the future should include more dynamic anthropometric metrics, such as neck stiffness and response to perturbation. In addition, laboratory-based mTBI studies should aim to standardise design and reporting to help further uncover these complicated relationships.

Age-related differences to neck range of motion and muscle strength: potential risk factors to fall-related traumatic brain injuries

BACKGROUND

Fall-related traumatic brain injuries (TBIs) are a serious health concern for adults over the age of 75 years, yet there is limited knowledge on possible modifiable risk factors. The neck is responsible for supporting the head during falls and age-related differences to the neck muscular could provide modifiable risk factors. However, there is limited empirical data pertaining to age-related differences in neck range of motion (ROM) and muscle strength in adults over the age of 75 years.

AIMS

To understand the age-related differences in neck muscle ROM and strength, we quantified neck active and passive ROM and isometric strength in four directions in young (18-30 years), young-old (60-74 years) and old-old (75-89 years) groups.

METHODS

57 participants were divided into groups based on age. Participants underwent testing of neck active and passive ROM and neck isometric strength in flexion, extension, and lateral flexion.

RESULTS

One-way ANOVAs revealed a significant effect of group on active and passive ROM in flexion, extension, and right and left lateral flexion (p < 0.001). Moreover, one-way ANOVAs revealed a significant group difference in only left lateral flexion strength (p < 0.030), yet there were large effect sizes observed between the young and old-old groups.

DISCUSSION

These findings suggest there are some age-related differences to the neck ROM and strength, which may be placing older adults at a greater risk for fall-related TBIs.

CONCLUSION

Future research should investigate the association between neck ROM and strength and head impact during falls in older adults.

Developing a Comprehensive, Interdisciplinary Concussion Program

There has been a growing trend of local and national coverage of and interest in concussion injuries over the past 2 decades. Increasing public concern over potential catastrophic and unknown long-term effects of sports-related concussion injuries has led to an acknowledgment of the strong public health need for addressing all concussion injuries, regardless of mechanism of injury. In efforts to address this need for concussion prevention and management, both in sports and nonsports, The University of Kansas Health System initiated the interdisciplinary Center for Concussion Management program in 2012. The program was created as a virtual clinic concept and includes voluntary participation from various providers across the institution, limited budget, and space obstacles. Since its inception, the program has continued to operate as its initial design of a multidisciplinary team model outside the sole ownership of 1 department, and has expanded to include education and outreach to local and regional schools and groups.

Age-related differences to neck muscle activation latency as a potential risk factor to fall-related traumatic brain injuries

This investigation examined age-related differences in neck muscle activation latency in response to anterior and posterior postural perturbations to understand the potential implications in fall-related traumatic brain injuries. 57 adults were recruited and categorized into 3 groups based on age: Young (18-30 years old), Young-Old (60-74 years) and Old-Old (75-89 years) group. Study participants underwent six anterior and posterior postural perturbations while bilateral sternocleidomastoid, upper trapezius, and splenius capitis electromyography was collected. Muscle activation latency time was calculated with established procedures. During anterior translations, a significant group effect for muscle activation latency of the right SCM (F(2,43) = 8.786, p < 0.001), right (F(2,34) = 4.838, p = 0.014) and left (F(2,34) = 5.015, p = 0.012) upper trapezius, and right (F(2,45) = 3.195, p = 0.050) and left (F(2,45) = 3.819, p = 0.029) splenius capitis was observed. During posterior translations, a significant group effect for muscle activation latency was observed in the right (F(2,34) = 6.419, p = 0.004) and left (F(2,41) = 5.275, p = 0.009) SCM, and the right (F(2,34) = 4.925, p = 0.013) and left (F(2,32) = 4.055, p = 0.027) upper trapezius. Both older groups displayed longer muscle activation latencies than the young group. The age-related differences in neck muscle activation latency may be placing older adults at a greater risk of fall-related traumatic brain injuries.

Underlying Ehlers-Danlos syndrome discovered during neuro-ophthalmic evaluation of concussion patients: a case series

Background

The Ehlers-Danlos syndromes are a heterogenous group of diseases that cause connective tissue defects. At present, there are no published reports focusing upon the neuro-ophthalmic symptoms that might occur in EDS patients after mild traumatic brain injury. The demographics and clinical course of seven patients with subclinical EDS and mild traumatic brain injury are presented.

Case presentation

This series describes patients with Ehlers Danlos Syndrome whose diagnosis was discovered in a neuro-ophthalmic clinic for brain injury. Patient demographics and neuro-ophthalmological symptoms are presented.

Conclusions

Patients with subclinical EDS and brain injury may experience a slower, less complete recovery course. Heightened awareness of undiagnosed or underlying Ehlers Danlos Syndrome is important for patients and providers.