Thank you for posting the nih website. The information was helpful. I have PD and "something else". In 2018 recovering from extensive back surgery, I had a pulling down sensation, pulling my chest forward and then becoming short of breath. I assumed it was from the surgery and that PT would take care of it. Two years later and it is getting worse. My PD doctor has come up with 3 different diagnostic names: abdominal dystonia, camptocormia, and diaphragmatic myoclonus. Two weeks ago he injected Botox into rectus abdominus muscles. I have had no improvements nor side effects. I think the reason I don't have back pain is because I have such a hard time breathing that I sit down quickly before the back gets involved. I have felt a pulling sensation in my lower back but the breathing difficulty trumps the back tightness. If Botox doesn't help I assume I will be confined to a wheelchair in the near future.