Doing pelvic floor exercises causes pain in si joint, i know muscle is attached to tail bone could the pulling of muscle cause si joint dysfuncation ?

SI Joint Disfunction: This is a common cause of low back pain. I treat several cases of it a day. Most of the time its from a strained ligament due to an accident or overuse injury. Different positions increase the pain. There are a lot of muscle attachments from the low back, hip and pelvis that can aggravate SI pain. Best results are achieved with a small injection of anesthetic and steroid into the ligaments.