Kinks? Rickets?

[Myca]

I found a very small corn snake at one of the pet stores I stalk and just had to hold it. This very little corn snake was very skeletal. Very emaciated. They said it had come in that way. I was struck with how thin this poor snake was. I noticed at regular intervals, I saw very small knots along the top of the spine. I assumed they were the crest of each back bone because the snake was so thin, but I am not sure what I was seeing. They weighed it while I was there and it weighed 56 gms so it was not a baby. Anyway, they decided to put it in the back and try it bring it around. I stopped in today and they told me it had gained 10 gms in the week they had it. It was out cruising it's bin, still in the back. I thought it had perked up since I had seen it before but I was still amazed at how thin it is.
Could those be kinks caused by malnutrition or really part of the skeleton?