Can you get pregunt from spem being close to your back bone and anus?

can you explain the question better? If your question is "Can you (a woman) get pregnant from sperm being close to your back bone and anus?" then the answer is "No." It has been known for a woman to become pregnant from sperm being close to the outside of her vagina but that also is highly unlikely because of (1) the conditions/distance the sperm would have to travel to the womb to find the egg to fertilise it and (2) the time taken over the lifespan/survival of the sperm. This is not an endorsement of indulging in anal sex.