Example 1 would be: They'll say you have sciatica with the nerve being pinched. That L5 or S1 is pinching it. First of all the sciatic nerve runs from L5 and down the sacrum, and down the hamstrings and calves, but the sacrum are all fused together into one. When we were babies, we had S1-S5 along with our coccyx bone: 1-4, but both structures fused together. Besides the L5 pinching the nerve, it'll be the piriformis muscle deep behind your butt (gluteus maximal). In the pictures you'll notice all these.
Example 2: They'll say hip pain is caused by the psoas major muscle. We got many hip flexor muscles causing hip pain. They only pay attention to one muscle at a time when it's more than that. They learned the anatomy and everything the same way I did but were taught to treat the bones alone, to improve posture and the nervous system/immunity. Again in the pictures you'll see the hip flexors that flex our hips. It's not shown but the pectineus is another muscle included, five muscles, just like five adductor muscles. Where you can see the psoas major, it fights the quadratus lumborum in the back. That's what alters our posture if we don't watch. Look up quadratus lumborum.
Hip flexors that flex the hip, pectineus not shown.
Piriformis and other muscles, piriformis affecting the sciatic nerve
The piriformis is the one that pinches the nerve as well, called piriformis syndrome. If you Google stretches for it, you'll find all kinds using a chair to being on the floor