Spinal diseases often induce gait disorders with multifactorial origins such as lumbar pain, radicular pain, neurologic complications, or spinal deformities. However, radiography does not permit an analysis of spinal dynamics; therefore, sagittal balance dynamics during gait remain largely unexplored. This prospective and controlled study try to assess the Vicon system for detecting sagittal spinopelvic imbalance and to determine the modification induced by ant induced anterior sagittal imbalance on the kinetics walking parameters

Inclusion Criteria:

• Male subjects
• Aged between 20 to 40 years
• Height between 165 to 190 centimeters
• Asymptomatic subjects from spinal point of view
• BMI < 30 kg/m²
• Affiliated to French Social Security
• Subjects having read the information note and signed informed consent

Exclusion Criteria:

• Subjects with neurological, vestibular, rheumatological or orthopedic pathology which can influence walking and balance
• Subjects with known spinal pathology
• Subjects with visible morphologic spinal deformity
• Subjects with significant visual impairment (visual acuity < 6/10) despite an optical correction port
• Subjects unable to walk without help
• Person placed under the safeguard of justice, guardianship or curatorship
• Subjects involved in other biomedical research during this study
• Subjects presenting an asymptomatic spinal pathology discovered at the inclusion on the spinal EOS images.