Your Back Pain Might Be Coming From Your SI Joint

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If you’re having lower back pain, you and your doctor may first turn to the usual suspects: The muscles and discs in and around your spine. But what if your pain is actually coming from somewhere else?

In some cases — perhaps one in four or five people with lower back pain — the culprit isn’t the spine at all. Instead, your pain may be coming from your sacroiliac (SI) joints. That’s where your hip bone links up with your lower spine.

When it comes to SI pain, the first and biggest challenge in treating pain from this joint is identifying it as the problem.

The main challenge is that SI joint pain masquerades as many other lower back pain disorders. Unless the correct diagnosis is made in people with SI pain, any treatment is unlikely to get at its true cause.

Unfortunately, SI joint problems can’t be diagnosed with an X-ray or similar technology. It can be spotted by a detailed examination.

Fortunately, once you know pain is coming from the SI joint, it’s easy to start treatment. Specialists who offer a full spectrum of treatments, from physical therapy to surgery, can help you with the path that's right for you.

Like other lower back pain, SI joint pain can affect a patient’s whole life. The pain is difficult to avoid, as walking, sitting and even rolling over in bed can put weight on this joint. Eventually, SI joint pain may lead to depression as it keeps people from doing what they enjoy.

The first step to relief from SI joint pain is to learn about this little-known part of the body.

What Is the SI Joint?

Your sacrum is a triangle-shaped bone at the bottom of your spine. It sits just under your lumbar spine and ends at the tailbone.

At each side of the sacrum, there’s a connection with your hip bone, or ilium. It’s called the sacroiliac joint because it’s where your sacrum and ilium meet.

Measuring from the center of your lower back, the joint is about an inch or two to each side. Its location is typically marked with a little dimple.

While the sacroiliac joint meets the technical definition of a joint — it’s a connection of two bones that allows movement — it’s not like the knee or the elbow. It shouldn’t move much at all, less than one-tenth of an inch.

Instead, the connection between our hip and spine is designed to hold these bones together tightly.

There’s one important exception: childbirth. As a woman enters labor, hormones tell this joint to loosen, giving more room for the baby to be born.

Aside from pregnancy, though, this joint isn’t supposed to move much. When it is too mobile, it can be painful.

Finding a doctor who is able to tell the difference between spine pain and SI joint pain may be the most important step in finding relief. Until that happens, any treatment is likely to focus on where it’s not needed, leaving the real problem to worsen.

How Is SI Pain Diagnosed?

Because identifying the real cause of SI pain is so important, find a doctor who listens closely when you talk about your pain.

SI joint pain tends to start on the sides of the lower back and spread out from there.

A lot of times, patients can point to where it hurts in their lower back and that can be a clue that their back pain is coming from somewhere else. It typically takes another step to diagnose SI pain.

Sometimes, specialists will inject a numbing agent near the joint. If you're still in pain, that’s a sign the problem is coming from somewhere else. But if the shot appears to be working and the pain goes down, it’s more likely the SI joint is the problem.

Many people with this type of pain can spend a long time before getting the right diagnosis.

Awareness in patients and even in many doctors in the SI joint is definitely still at a low level even though studies have found that between 22% and 32% of lower back pain may originate in the SI joint.

What Causes SI Joint Pain?

An injury, perhaps from falling down at home or a traffic accident, is a common cause of SI joint pain. In other cases, it can be caused by nearby surgeries or pregnancy.

In many cases, though, there’s no obvious cause.

How Is SI Joint Pain Treated?

As with other joint pain, SI problems are treated first with non-surgical options. In some cases, temporarily cutting back on activities that cause pain can give it time to heal.

Physical therapy — including heat, massage and stretching exercises — can sometimes stabilize the muscles around the joint. Injections of steroids can cut down on inflammation.

For many people, these steps provide a solution. But if a person is still in pain six or nine months later, surgery may be required to fuse these bones together.

How Does SI Surgery Work?

To “fuse” something means to bring its parts together, and the goal of this surgery is to tightly connect the lowest part of the spine (the sacrum) to the hip bone (the ilium).

AdventHealth experts perform this surgery using minimally invasive techniques, meaning we use small cuts to minimize pain and reduce recovery time. Patients who undergo this surgery are put to sleep, so they don’t feel pain during the operation.

As with joint and knee repair surgery, the implants have tiny holes so the person’s bone can grow into it. Within a few months after surgery, the patient’s bones have typically attached to the implant, which is why it’s unlikely to break.

The procedure itself is short, usually less than an hour. Afterward, patients are advised to use crutches or other tools to avoid putting weight on the joint. But they typically notice a difference soon after waking up from surgery.

Most of the time, pain relief is quite dramatic and quick. Many patients notice a difference the first time they get out of bed after surgery, and by the two week mark, the results are even better.

At AdventHealth, we don’t just treat your joints, we treat you as a whole person. Being able to move without pain is part of your holistic health, and our surgeons, sports medicine experts and physical therapists can help you regain your strength and confidence.

For more information on bone and muscle care at AdventHealth, visit our website.

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