Is it time for another medical curriculum revolution?

Abstract

<h3>Objective</h3> To compare linear and rotational acceleration across age and gender in controlled purposeful soccer heading. <h3>Design</h3> Prospective study. <h3>Setting</h3> Biomechanics laboratory. <h3>Participants</h3> One-hundred soccer players (42 male, 58 female, 17.1±3.5 years, 168.5±20.3 cm, 61.5±13.7 kg) classified as collegiate, high school (HS), or youth (12–14 years) male (MS) or female (FS) soccer players. <h3>Exclusionary criteria</h3> history of neurologic disorder, cervical spine injury, or head injury in the past 6 months. <h3>Interventions</h3> We implemented a unique soccer heading paradigm that allows for precise control of head impact magnitude, direction, and frequency to model repetitive head impacts in sport. This model consists of controlled soccer heading (12 headers at 11.2 m/s from a JUGS machine) while measuring linear and rotational accelerations using a triaxial accelerometer and gyroscope affixed to the back of the head. Linear accelerations were transformed to the head center-of-gravity using 3D motion capture data and standard rigid body dynamics equations. <h3>Outcome measures</h3> Linear and rotational accelerations at the head center-of-gravity. <h3>Main results</h3> [Average±Standard Deviation (95% Confidence Interval)] Collegiate [42.4±11.5 g (36.8–47.9); 3.35±0.87 krad/s²(2.9–3.8)], HS [38.5±13.1 g (32.2–44.8); 3.16±1.01 krad/s²(2.7–3.7)], and youth [40.5±14.9 g(33.1–47.9); 3.20±1.24 krad/s²(2.6–3.8)] FS produced higher linear and rotational accelerations than both the collegiate [26.1±9.5 g(21.7–30.6); 2.13±1.07 krad/s²(1.6–2.6)] (linear: p&lt;0.001, p?= 0.012, p=0.002; rotational: p=0.002, p=0.015, p=0.011, respectively) and HS [26.7±5.9 g(23.2–30.1); 2.18±0.40 krad/s²(2.0–2.4)] (linear: p=0.002, p=0.045, p?= 0.012; rotational: p=0.011, p=0.052, p=0.040, respectively) MS. <h3>Conclusions</h3> Collegiate and HS FS have higher head accelerations than their male counterparts, but at the youth level, there are no differences across gender. These data suggest that FS may be exposed to greater cumulative head accelerations from repeated heading of a soccer ball over a career than MS. <h3>Competing interests</h3> None.