Can the SI joint cause sciatica?

Hi everyone!

I was just going through some old papers last night and found an article I printed out long, long ago (like 2012), when I was first trying to learn about the SI joint.

Wow… how far I’ve come since that time.

Many of you have asked me over the years whether the SI joint can cause sciatica.

Here’s a study that proves that yes, it can.

In this study, researchers at the Indiana University School of Medicine used a variety of measures to analyze whether inflammation from an injured SI joint could actually travel outside of the joint and irritate the nearby sciatic nerves.

They used a few different methods to prove that this was happening, proving in particular that a chemical called Substance P— which is associated with nerve pain and inflammation— was indeed traveling to the roots of the sciatic nerve. (For those of you who geek out over this stuff, those elements of the sciatic nerve range from L4-S2).

The study authors also point out what I’ve heard mentioned previously, about how up until the 1930’s, the SI joint was actually considered to be the main cause of back pain.

After that point, most doctors began to shift their focus onto the spine itself as a source of pain, and the SI joint was rather neglected (as all of us know!).

So I really appreciated how, at the end of the article, they tied it back and said “We believe that the pre-1934 belief that sciatica may also be associated with SIJ dysfunction also has merit.”

Indeed, it does, and I’m happy to say that awareness of SI joint dysfunction is making a comeback!