muscle weakness?

[mema008]

My 6 month old grandson is not rolling over or even attempting to. Also when he is put in his jumper seat he doesn't jump up or down. He doesn't like to be put on his stomach even for a little "tummy time". He does grab at objects and moves his arms and legs when he is in his bathtub. His neck mussels seem strong as he holds his head up without a problem. When he is being held he keeps his arms down at his side. Any suggestions?

Thank You,
Mema008

[Kevin Kennedy, Ph.D.]

As you probably already know, by the age of six months it is expected that most babies will be able to sit up, having learned to roll over around the age of three-four months. Now it is important to remember that not all children achieve these milestones at that exact age; some are early in their motor development and some are later. What is clear is that your grandson is at the late age in regard to these aspects of gross motor development. Is this the sign of a problem. Not necessarily, but perhaps. His parents should definitely call this to the attention of his pediatrician, because it is possible that the delay is caused by some problem in muscle tone and strength.

[sandysandy]

My daughter never crawled and turned over once.  Yet, she was up and walking at 9 months and all other milestones where met on time or earlier.  However, we discovered recently that she has a familial collagen disorder.  In my reading of the disorder, I learned that many babies who are born with it don't crawl due to loose shoulder joints or hypotonia.  As a teen she has problems with her shoulders falling out of socket (if she doesn't do her exercises).  When I look at her baby pictures, he skin was translucent (arteries showing), her feet had a wide splay, and her legs were always open wide in the joint.

So I would get it checked out and keep an eye on it.  My daughter... even if this collagen disorder was known to exist in the family at that time... would not have been diagnosed at such a young age.  However, if suspected it would have helped her doc and us to help her in her elementary years.