scoliosis

im a 20 year old student, and i have been diagnosed with scoliosis since last march, my curveage is about 40% an had to have a mri and ct scan so the surgeon could have a look at if if surgery was possible...wen he got the result he said that he had notcied a small hole (an incision)in my spine at the top of my neck and its been there since birth, and due to that i have gto scoliosis because of that my body didnt structer proply,so surgery would be risky ...can u tell me what that hole is called and how it happens an is it risky?