i am a researcher in biomechanics of infant spine (infant spinal rom), however, there is one studies has only described the degree of cervical rotation and lateral bending in infant. so, the spine and cervical flexion and extension rom has not investigated yet for newborn and infant to 24 months. therefor, i would like from your excellencies, what is the best scientific expression that i can convince the examiners and academic people when they asking that, "how do you know you've got the full range of motion without causing harm to the baby?". what the best answer for such tricky question. best regards Less