Km. Guskiewicz et al., ALTERNATIVE APPROACHES TO THE ASSESSMENT OF MILD HEAD-INJURY IN ATHLETES, Medicine and science in sports and exercise, 29(7), 1997, pp. 213-221
Objectives: Athletic trainers and team physicians are often faced with
decisions concerning the severity and timing of an athletes return to
play following mild head injury (MHI). These decisions can be the mos
t difficult ones facing clinicians because of the limited amount of qu
antitative information indicating injury severity. Several authors hav
e published guidelines for return to play following MHI, however these
guidelines are based on limited scientific data. The purpose of this
paper was to examine the effects of MHI on two objective measures, pos
tural stability and cognitive function, to determine their usefulness
in MHI assessment. The data gathered from these two measures has the p
otential to establish recovery curves based on objective data. Methods
: Eleven Division I collegiate athletes who sustained a MHI and eleven
matched control subjects were assessed for postural stability and cog
nitive function at four intervals following injury. Postural stability
was assessed using the Sensory Organization Test on the NeuroCom Smar
t Balance Master. Cognitive functioning was measured through the use o
f four neuropsychological tests: Stroop Test, Trail Making Test, Digit
s Span and Hopkins Verbal Learning Test. Separate mixed model repeated
measures ANOVAs were calculated for the composite score and three rat
io (vestibular, visual and somatosensory) scores from the Sensory Orga
nization Test and the scores from the neuropsychological test to revea
l significant differences between groups and across days postinjury. R
esults: A significant group by day interaction for overall postural st
ability (composite score) revealed that MHI athletes displayed increas
ed postural instability for the first few days following MHI (p<.05).
Analysis of the ratio scores revealed a significant interaction for th
e visual ratio. No significant group differences were revealed for any
of the neuropsychological tests (p>.05), however significant day diff
erences were revealed (p<.05). Conclusions: The results from this stud
y indicate that athletes demonstrate decreased stability until 3 days
postinjury. It appears this deficit is related to a sensory interactio
n problem, whereby the injured athlete fails to use their visual syste
m effectively. These findings suggest that measures of postural stabil
ity may provide clinicians with a useful clinical tool for determining
when an athlete may safely return to competition, although these find
ings need to be confirmed in larger groups of athletes.