Characterization of Neck Strength in Healthy Young Adults

Abstract

Background The role of cervical muscle (neck) strength in traumatic brain and spine injury and chronic neck pain disorders is an area of active research. Characterization of the normal ranges of neck strength in healthy young adults is essential to designing future investigations of how strength may act as a modifier for risk and progression in head and neck disorders. Objective To develop a normative reference database of neck strength in a healthy young adult population; and to evaluate the relationship of neck strength to anthropometric measurements. Design Cross-sectional. Setting An academic medical center research institution. Participants 157 healthy young adults (ages 18–35) had their neck strength measured with fixed frame dynamometry (FFD) during one visit to establish a normative neck strength database. Interventions Not applicable. Main Outcome Measurements Peak and average strength of the neck muscles was measured in extension, forward flexion, and right and left lateral flexion using FFD. The ranges of peak and average neck strength were characterized and correlated with anthropometric characteristics. Results 157 subjects (84 male, 73 female; average age 27 years) were included in the normative sample. Neck strength ranged from 38–383 Newtons in men and from 15–223 Newtons in women. Normative data are provided for each sex in all four directions. Weight, BMI, neck circumference, and estimated neck muscle volume were modestly correlated with neck strength in multiple directions (correlation coefficients <0.43). In a multivariate regression model, weight in women and neck volume in men were significant predictors of neck strength. Conclusions Neck strength in healthy young adults exhibits a broad range, is significantly different in men than in women and correlates only modestly with anthropometric characteristics.

MRI-defined White Matter Microstructural Alteration Associated with Soccer Heading Is More Extensive in Women than Men

“…Several studies measured heading acceleration in men and women under controlled conditions and found greater acceleration in response to a similar force applied to women, which was attributed to anatomic differences between the sexes (43)(44)(45). Sex-based divergence of neck strength and anthropometrics (46) may have also played a role in our findings, but other factors such as genetics and hormonal influences may have contributed as well. Future studies examining each of these possibilities, and others, are necessary to uncover the mechanistic basis for the sex differences.…”

Sex Differences in Animal Models of Traumatic Brain Injury

“…26 Various mechanisms have been postulated as to why men and women have different outcomes following concussion and subconcussive injury, such as force of injury, number of injuries, skull and brain shape, neck strength, and hormonal influences. 27,28 Further investigation, including in animal models, will be necessary to isolate individual aspects of injury and recovery to develop new modes and methods for treatment.…”

Neck Injury Comorbidity in Concussion-Related Emergency Department Visits: A Population-Based Study of Sex Differences Across the Life Span

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“…, thoracic and lumbosacral) of the spine. 18 Evidence also supports that females have weaker and anatomically distinct necks than males, 19,20 which suggests that the relationship between neck injuries and concussions may be sex-dependent and that biological differences between males and females may be responsible for the observed increased vulnerability among females to sustain whiplash in motor vehicle collisions (MVC), 21,22 poorer prognosis following injury, 23,24 and increased risk of concussion. 25…”