I practice power vinyasa yoga 3x /week. About a year ago I (re-)pulled my right groin/adductor muscle. I have have had several strains like this that alternate between the right and left side. This time however, it is taking a long time to heal. Poses like supta bada konasa are fine, however when my leg is extended and go into a straddle variation like Upavistha Konasana or Prasarita Padottanasana, it kills! I also sit for long periods in a car…commuting 12 hrs/week to work. My chiropractor has also recently told me that my lumbar curve is somewhat flat. I do have lower back pain when I don’t practice yoga for several days. Is this a sacroiliac issue and what can I do about it? Thanks!
Sounds like your hip alignment may be all out of whack. I would try to talk to a physical therapist, because they, more than pretty much anyone, can address the problems that arise from, say, your hip alignment being off. A small misalignment can cause injury in yoga that you would not otherwise get. This is what happened to me, and the physical therapist gave me exercises that addressed the problem quickly and effectively.
I’m going to take a slightly different approach.
The first part is that when we have a behavior with a particular result it may be unreasonable to expect a different result unless that behavior is altered. I’m not trying to be terse but the nature of the practice and practitioner may have a causal relationship. And, of course we know that injury manifestation in the physical body is a phone call from body to mind, awaiting an answer.
As for P/T, I find that the P/T protocol is almost always “strengthen”. And while strengthening is perfectly fine, in yoga it follows alignment.
Nothing the OP has said thus far sounds like an SI issue. “Lower back pain” is so general a phrase that it’s impossible to tell if it’s short and tight hip flexors or an issue with the Quadratus Lumborum.