Hi

I was a Physio Assistant before starting my Physio degree. Patients recovering from spinal injuries/pain would often ask about picking up objects etc......They were advised to get as close to the object as possible, test its weight by tilting it before picking up, ensure it was well balanced, weight equally distributed, and when lifting keep a straight back and use the power of your quads to lift, when object is lifted avoid too much twisting movements when standing static.......You probably new most of this . The fact that is is a child car seat is no different from any other object, maybe they want you to point out during pregnancy a mother may have put their lumbar spine through a lot of stress, and needs to avoid sudden jarring movements, and that a car seat is an awkward shape......

Just a couple of thoughts, hope they help a little