What is a good homeopathic medicine for spinal pain after spinal injection?

Arnica, Hypericum: The most widely used homeopathic remedy is probably Arnica, used for all sorts of injuries and trauma. Also consider Hypericum, which is useful for nerve pain, esp. related to injury. You might also try Ledum, which is helpful for puncture wounds. Try these in 12c and/or 30c potencies. I might try each one 2-3 times a day for a day or 2 sequentially to see which helps most. Hope they help!