Of 55 patients who presented with a head injury, 22 were not eligible or declined to participate. Of those who consented to participate, concussion was diagnosed in 16 participants. Patient ages ranged from 18 to 26 years. The study included 10 men (62.5%) and 6 women (37.5%). On physical examination, 11 patients (69%) had nonphysiologic SBS somatic dysfunctions, 9 of which were lateral somatic dysfunctions. Patients were 1.67 times more likely to have a nonphysiologic SBS cranial somatic dysfunction (
P=.442). New-onset impairment (below average) from pre- to postconcussion ImPACT scores was found in 3 physiologic (60%) and 8 nonphysiologic (73%) somatic dysfunctions (
Table 1). Those with nonphysiologic somatic dysfunctions had new-onset impairments in a mean of 2.13 out of the 4 ImPACT categories, compared with 1.2 in physiologic somatic dysfunctions. Mean changes for verbal memory in physiologic somatic dysfunctions were 22 points worse for right torsions than SBRs. Mean changes in category scales were not significant. Visual memory score changes were −4.2 for physiologic and −21 for nonphysiologic somatic dysfunctions (
P=.237). Mean changes for processing speed were −4.17 for physiologic and −7.25 for nonphysiologic strains. Mean changes for reaction time were 0.01 for physiologic and −0.11 for nonphysiologic somatic dysfunctions (
P=.162). There were a total of 5 physiologic cranial somatic dysfunctions, 3 SBR somatic dysfunctions, and 2 torsion somatic dysfunctions. Of samples with the same direction of impact, impact onto the back of the head (n=4) was correlated with vertical SBS somatic dysfunctions (Φ correlation coefficient=.655; n=2;
P=.006) and negatively correlated with strains around the vertical axis (Φ correlation coefficient=−.667; n=12;
P=.005). Otherwise, concussive impacts to similar parts of the head (n<3) were not substantial within the limited sample size (
Table 2).