A couple of times by accident. The first on a spike, my first deer. That shot was from the side. Then the second many years later on a seven pointer, and that shot was nearly straight down.
On the seven pointer the two blade magnus penetrated the backbone and the spinal canal. The head was parallel to the spinal cord with its tip wedged into the backbone beneath the spinal cord. The deer survived. Eleven days later, two farms over I kicked him out of some corn strips and took him with the shotgun. I couldn't believe the broadhead was wedged so tightly and never broke his back. Since the single blade was parallel to the spinal cord and just off to the side the buck was completely mobile.
Dan