Brief Answer:
need some investigations.

Detailed Answer:
Hello!
Welcome to Healthcare Magic.

I read carefully your query and understand your concerns.

There are some possible causes .Depending on the time that this occur it might be congenital or acquired.
If this problem is diagnosed in an infant most likely it has a congenital cause that might be an malformation of ribs ,vertebral column , congenital scoliosis etc.This may happen if during the embryogenesis ,one of the components of thoracal wall develops with defects or doesn't develop at all.

If this problem is noticed in an adult (that had symmetrical rib cage in infancy ) most likely it is acquired like acquired thoracal scoliosis due to bad posture, accidents ,Severe Vitamin D deficiency (this is very rare nowadays because only the frequent exposure to sun light can produce enough Vitamin D ) etc.

In both cases is difficult to say something more without doing a physical examination first.
Some investigations like X-ray of the chest (antero-posterior and lateral views) CT-scan of chest, are necessary to determine the cause of asymmetrical ribs.
It is very important to determine a diagnosis because a deformed chest wall can cause problems with heart and lungs function in the future.

I suggest to consult a physician and get examined.

Hope it helps.
Let me know if you have any other question or doubts to clarify.I will be happy to assist you further.

Kind regards,
Dr.Rovena Murati

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Brief Answer:
most likely a congenital malformation.

Detailed Answer:
Hello!

It seems to be a congenital problem.As I said there are some possible causes including : ribs or vertebral column malformations ,infantile scoliosis .
As the kid grow up ,the problem may become more evident or less obvious ,it depends on the cause.

The only way to determine the cause of his unsymmetrical rib cage ,is to do some imaging studies of the chest wall and vertebral column.


Hope it helps.
Take care,

Dr.Rovena

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