I think you may need a second opinion. I couldn't tell where you were posting from.
In idiopathic scoliosis, there are several age categories. Infantile is diagnosed from birth to age 3, I think. Juvenile is diagnosed from ages 3 to 10. Adolescent is diagnosed from ages 10 to maybe 18(?) My daughter has juvenile idiopathic scoliosis, and was diagnosed at age 7, but I ran across a CAT scan done when she fell out of a tree at age 5, and the curve was visible to me, although it had progressed in the 2 years between.
Whether or not the curve is a congenital curve depends on the structural defects present. In idiopathic scoliosis, there is a structural defect, but no hemivertebrae(partial vetebrae that didn't form inutero, I think),etc. THe structural defect in idiopathic scoliosis is in the shape of the vertebrae. I don't know how hard it is to tell from an x-ray which it is. I have no experience there, but there are many on this forum that know a tremendous amount more than I do.
Adolescent idiopathic scoliosis(AIS)is diagnosed in both boys and girls, but progresses more often in adolescent girls to the point of surgery or bracing, if I understood correctly at our last appointment. (We had a short discussion because I rarely see boys in the office.)
A left thoracic curve is NOT common. In thoracic curves, right is most common.
I am concerned that this physician did not give you more information, and more accurate information.
There are others on this forum that can shed more light than I can on congenital scoliosis.
Shriners does a fantastic job. You might consider a second opinion at your nearest Shriners.
God has used scoliosis to strengthen and mold us. He's good all the time!On this forum these larger curves have not held forever in Spinecor,with an initial positive response followed by deterioration. With deterioration, change treatment.The first year she gained 4 or 5 inches and was stable at around 20/20 in brace, followed by rapid progression the next year.She is now 51/40 (Jan2008)out of brace (40/30 in Spinecor) and started at 38/27 out of brace(Jan2006.) Now in Cheneau.