I'm DO student almost finished my 2nd year. I actually finished my 4 semesters of OMM today and am looking forward to having more free time to study for my boards.
I'm not an expert, but I agree that if I had a problem I would seek a DO that has done an OMT fellowship. However, there are many techniques that don't use the force of HVLA (myofascial or lymphatic for example) and have minimal to no likelihood of injury, depending on the patient's preexisting conditions. That being said, the competency of the physician (or chiropractor) is most important. A DO without fellowship training should have no problem utilizing lymphatic techniques to aid in fluid movement in a patient with CHF, but for more complicated issues I would seek a DO that specializes in OMT.
To the OP, I apologise for going off topic, but I would check with your family doc first!