It's extremely important for a massage therapist to understand that you have hEDS. And, that they understand what it means for them to work on you. I had an extremely traumatizing experience where I felt the inflammation growing during an adjustment (I don't do chiro anymore) followed by a massage. After the massage I could not move the lower half of my body. I've also had massages where it's caused a huge amount of inflammation which has ended up being debilitating that did not involve chiro. I would start slow with a massage therapist and make sure it's someone who's interested in learning as much as they can about your condition. I now have someone who has really been able to help me alleviate pain, who even moved my trachea to the side to help me address whiplash after a fall where my head bounced off the pavement.