Reproducibility Inter-session of the Measurement Elastography of the Passive Stiffness of Medial Beams of Gastrocnemius Muscle of the Hemiplegic Cerebral Child.

Overview

Muscles, paretics and spastics, of cerebral palsy children have very early, for growth (three at five aged), every alteration of theirs properties. Gastrocnemius muscle, often reaches on the cerebral palsy, characterised by a modification of the structure (volume decrease) and the elasticity (increase of the passive stiffness). Every alterations of the muscular property have impact clinic and functional important. The many treatments of orthopaedic targeting (lengthening of cast, injections of botulinic toxin), repeated to a multiple recovery during the growth influences the muscular characteristics. There is a real interest to measure the muscular property development during children's growth.

Elastography is a technical assessment of characteristic of the soft tissues. In this area, the method " Supersonic Shear Imaging® (SSI) " provide an important technological change measuring, swiftly and no invasive, a elasticity modulus reflecting the property visco-elastic of the muscle. A lot of ex vivo study led in isolated muscle and in vivo in healthy adults demonstrated the validity of the method SSI on the evaluation of the passive stiffness from a number of muscle group whose the gastrocnemius muscle. The main objective of this study must be checked the intersession reproducibility of the method SSI on the evaluation of the passive stiffness at the medial bundle of the gastrocnemius muscle therefore their passive lengthening in cerebral palsy children. The secondary objective is to test the correlation level of the relation elasticity modulus/ joint angle and couple force-angle obtained throughout the passive lengthening at the medial bundle of the gastrocnemius muscle in cerebral palsy children.