Sc. Allison et Ld. Abraham, Sensitivity of qualitative and quantitative spasticity measures to clinical treatment with cryotherapy, INT J REHAB, 24(1), 2001, pp. 15-24
This study examined the extent to which a battery of tests could detect a r
eduction of plantarflexor spasticity resulting from cryotherapy. The tests
included a traditional qualitative spasticity scale, three potential quanti
tative spasticity measures and a measure of voluntary ankle muscle function
. Twenty-six adult traumatic-brain-injured subjects were examined; these in
cluded 22 males and 4 females. The mean age was 28.15 years (range: 18-57,
SD 10.78). The five tests were performed in random sequence on both ankles
of each subject, before and after a 20 minute cold pack application to the
calf. Tests were: modified Ashworth scale (MAS) scoring; H-reflex testing w
ith and without dorsiflexor contraction (Hdf/Hctrl ratio); H-reflex testing
with and without Achilles tendon vibration (Hvib/Hctrl ratio); reflex thre
shold angle (RTA) and timed toe tapping (TTT). Cryotherapy resulted in lowe
red MAS scores consistent with a reduction in spasticity. Doubly multivaria
te repeated measures ANOVA revealed a significant difference (F = 24.16, P
< 0.001) in test scores between the pre- and post-cryotherapy test batterie
s. Significant pre- and post-cryotherapy differences (P <less than or equal
to> 0.03) for all dependent measures contributed to the main effect for cr
yotherapy. However, among the potential quantitative measures of spasticity
only the RTA test demonstrated appropriate sensitivity to the reduction in
spasticity. In spite of spasticity reduction, TTT performance was impaired
following muscle cooling. Failure bf the H-reflex ratios to show a reducti
on consistent with reduced spasticity was attributed to competing alpha and
gamma motoneuron effects resulting from peripheral cooling.