<s>[INST] I have a knot on my spine a little lower than the middle of my back it doesnt move i have had it for a few months now at least its causing me back pain in the upper back and my legs to go tingly and numb it has recently gotten bigger what is it and is it something i should be concerned about [/INST] Hiyes you should be concerned about the swelling you have as it has started giving you symptoms of nerve being compressed. You require being be done MRI of the affected spine to know the extent of nerve compression, after getting an ultrasound of the lump you have, according to the ultrasound you might require a fine needle aspirate to be done to know what is the lump.I would suggest go see a specialist to sort you out. Hope have answered your query. Thanking you. </s>