Echographic aspects of spastic muscles: Changes after antispastic treatment with Botulinum toxin

AbstractThe ultrasound (US) scan is applied in the analysis of muscular structure in myopathies and paralysis. This work shows the US aspect of the spasticity due to pyramidal lesions. The spastic muscles of ten subjects (8 males, 2 females) were studied by US before and after a local injection of Botulinum toxin. The spasticity was quantified by the Ashworth scale and by a byomechanic-electromiographic test. In spastic muscle the echointensity was higher and the thickness lower than normal; the comb framework typical of the muscle skeletal structure was preserved. After Botulinum toxin injections, which reduced the hypertonia and increased the stretch reflex threshold, the US muscles' hyperechointensity decreased and, in some cases, the fibers' thickness increased. In conclusion, the hyperintensity seems a typical aspect of the spastic muscle not only due to fibrosis that is irreversible, as it decreases after antispastic therapy.