How do you know if you cracked a rib or if it's the muscle? i do have osteoporosis. i bent over and felt/heard lg pop then instant pain.

X-ray: An x-ray is the only way to be sure that you did not break a bone, anywhere. However, unless your osteoporosis is severe, just bending over is not all that likely to crack it, while an injury to the ligament or muscle is much more probable. If you have shortness of breath, dizziness, severe pain, vomiting, etc. go to an ER or UC, If not that bad, see doc soon.