But as with any activity there is a chance of injury. What I love about Iyengar yoga is that risk of injury is reduced due to the teaching of the body what movements need to be made, and the high level of training from certified teachers (IYCT). The higher up they are certified there is a lot more knowledge and practice to guide you through learning yoga.
But what happens if that injury happens? This last 2 months I have been healing from a back pain that I received from attempting my standing back bend. I did them, but there were a few times I fell (like 20) and other times I contorted my body to "get out of the pose easier". It was completely wrong and most likely where I injured my back.
So now I am injured what do I do? I do not do back bends, I give my body a chance to heal. I have been doing a restorative sequence that does not include strenuous poses, and allows for the healing time which could a bit longer. I told you I was working on patience.
If you were injured during a home practice, stop doing that class of poses (standing, forward bend, back bend, inversion, twist), give your body space, and look for an experienced yoga instructor that has knowledge in therapeutic yoga. Slowly build your practice back up with their assistance and be patient. This may mean not going to a favorite class, or going to the class and doing a modified pose. We must respect our body as part of our yoga.
How do I prevent future injuries? First and foremost take my ego out of my practice, I went into a pose that I did not have enough instruction on how to accomplish it. I was caught up in the "wow look I am going to do this". While this excitement is good and needed to help progress don't let it take over your natural warning symptoms. I kept practicing the pose even when there was pain.
There is a difference between discomfort and pain. Learn your body and feel the difference. If you experience pain come to a modified pose.
Just yesterday I had a student who has back pain. We were doing Setu Bandha Sarvangasana, with no brick under the feet.