Infant: Hyper-flexibility and delayed development 

Birth and early infancy

J was born following an uneventful pregnancy, labor and delivery.  Post-partum, J was noted by her mother to be hyper-flexible in her hands and feet. Her left hip was dislocated and was treated with a closed hip reduction with casting. She was also diagnosed with torticollis.   

Family History

J had one healthy older sibling and no family history of dislocation, birth defects, or genetic disorders.

Growth and Development

With intense physical therapy, J’s development progressed but she remained delayed at meeting her developmental milestones.  The physical therapist noted a contracture in J’s elbow.

She sat at 7 months, did not crawl, and walked at 17 months.  Her parents continued to notice her hyper-flexibility and her PT noted mild generalized weakness.   Due to these concerns, at age 2 years her pediatrician ordered a CK, which was normal.

Clinical Pearl: Children with some neuromuscular disorders have a normal CK. Normal or near normal CK should not be reassuring if a child is weak or losing milestones.

What should have occurred, based on J’s developmental history?   

Now read what happened.

Diagnosis

J’s parents were concerned when she seemed to have increased difficulty walking at age 3 years.  Her pediatrician referred her to a pediatric neurologist. Following an evaluation, genetic testing was ordered.  Results showed a single mutation in the collagen VI alpha 1 gene and J was diagnosed with autosomal dominant Ullrich CMD. J’s parents expressed great relief in having a diagnosis, and were referred to genetic counseling to learn about risks to subsequent children.  

Clinical Pearl: Children with some neuromuscular disorders have a normal CK.  Normal or near normal CK should not be reassuring if a child is weak or losing milestones.