Outcome evaluation of surgery treatment by means of gait analysis in children with cerebral palsy: The normality pattern is not an effective term of comparison

34 79 False detection rate (FDR) 80% sion criteria: concomitant medullar lesion, akinesia or iperkinesia, hydrocephalus, cerebellar syndrome. Patients with elicitable ankle clonus were also excluded. A single experienced rater assessed the MAS score for all patients, at their bed, for gastrocnemius medialis (GM) and lateralis (GL), and soleus (SOL) muscles. The presence of reflex muscular activity was measured by surface EMG, used as the criterion standard to assess the presence of spasticity. Bi-polar surface electrodes (ARBO H124 SG, diameter 15 mm, interelectrode distance 20 mm) were placed on the minimum crosstalk points recommended in [5]. EMG data were collected at 1000 Hz (PocketEMG, BTS, Italy). During the MAS assessment sEMG data were acquired but not displayed to ensure the assessor’s blindness to the presence of EMG. The presence in sEMG traces of muscular activity consequent to the stretching manoeuvres was assessed separately by visual inspection by an experienced operator. This assessor was blind to any information on patients and, mainly, to all MAS scores. A score “Yes” was given to trials with EMG reflex activity, and a score “No” was given otherwise. Results Results are presented in Table 1.