Reportage on the Rossetti health centre in Nice, France. This rehabilitation centre is a hub of excellence with cutting-edge technology. Seen here, a quantified motion analysis test carried out in the Clinical Motion Analysis Unit, a technical platform enabling a better understanding of walking anomalies. This 15-year old boy suffers from cerebal palsy, is mentally and physically retarded and has orthopedic disorders. He talks to the engineer who will carry out the test.