I would not be surprised. A few years ago I developed disabling inflammation in my wrist, which turned out to be caused by my tendons having grown in an abnormal configuration. A simple surgery that "released" the collar of the sheath holding the tendons provided relief.

My surgeon told me that some segment of the population has the same issue and that they are simply born with it, but he is not sure what percentage it is, and some may go a lifetime without ever knowing.