asymmetrical growth of arms

Does anyone have any idea why my sons arms are different sizes? His left arm which is NOT his dominant arm is larger than his right arm (dominant). It is his entire arm and hand, including shoulder muscle. The arm at the shoulder is 1 inch larger and his fingers are about 1/2 longer. Does anyone know of a syndrome to explain this. His doctor has not seen this before. I have comparison x rays, but he will not be seen for 2 weeks by an orthoped.

Thank you for any insight

[Ashwin Bhandari, MBBS]

Hi, Thanks for the query. he might be suffering from coarctation of aorta or a chromosomal defect. Karyotyping of the chromosomes can tell you if there is anything wrong. Sometimes an extra rib can also cause growth retardation in one arm. See a physician before approaching an ortho. Have a nice day.