You might think the most common source of low back and leg pain is a bad disc. My practice of 39 years has taught me differently. It’s the sacroiliac joint. You have one on each side behind the hips, about where the inner top corners of your pockets on your jeans are. These joints don’t move much because they are fibrous, gristly structures, unlike other joints in the body. If they are locked and not moving properly, they can raise hell.

The pelvis is a ring of bone, and sacroiliac joints are the major joints in this ring. Locking one or both of these joints can hold the pelvis in a twisted position. In this case, the sacrum (the base of the spine) will not be level, and the muscles of the low back will work overtime trying to hold the spine straight. It’s like trying to build a house on a crooked foundation. This causes low back pain, and will eventually affect the entire spine. 

You have branches from a number of nerves in the low back that course into the sacroiliac joints. Dysfunction of these joints can irritate the nerves, causing various symptoms. Pain in the groin, front of the thigh, side of the leg, back of the leg or buttocks is common. Many people believe they have sciatica because they have pain down the back of the leg, but most often it is the sacroiliac joint. True sciatica, which is irritation of the sciatic nerve, extends down the back of the leg to below the knee, often to the foot. Sacroiliac pain typically will not go lower than the knee.

The best way to move the sacroiliac joints is to stand with your feet spread out farther than your shoulders. Keeping your head still, rock your hips side to side. If this doesn’t help, it’s time to see your chiropractor.