The sacroiliac joint is a common and often overlooked source of low back pain. If your pain sits low in the back, often on one side, and radiates into the buttock or leg, this joint may be the culprit. Fixing SI joint pain starts with targeted movement, avoiding aggravating positions, and understanding that a “cure” often means long-term management rather than a quick fix.
What Is the SI Joint and Why Does It Hurt?
The sacroiliac joint connects your sacrum (the triangular bone at the base of the spine) to your ilium (the large pelvic bone). It is a strong, weight-bearing joint with very little movement. Its job is to transfer force between your upper body and your legs.
Pain occurs when this joint moves too much, moves too little, or becomes inflamed. The joint is supported by strong ligaments that can stretch, tear, or become irritated. Unlike a knee or shoulder, the SI joint is not designed for much motion, so the pain is often a deep, aching sensation rather than a sharp, pinching one.
SI joint pain is frequently misdiagnosed as a disc problem or sciatica. The pain can feel similar because the nerves near the joint can refer pain into the buttock and down the back of the leg. A doctor can help distinguish SI joint pain from other causes with a physical exam and imaging if needed.
What Causes SI Joint Pain?
Several factors can contribute to SI joint dysfunction. Pregnancy is a common cause because hormones relax the ligaments to prepare for childbirth, which can make the joint less stable. A fall onto the buttocks, a car accident, or repetitive lifting can also strain the joint.
Leg length differences are another cause. If one leg is shorter than the other, the pelvis tilts unevenly, placing extra stress on one SI joint. Arthritis can affect the SI joint just as it affects other joints, causing stiffness and pain.
After spinal fusion surgery, the SI joint often takes on extra load. Some research suggests that a significant number of people who have had lumbar fusion later develop SI joint pain because the joint compensates for the fused segments above it.
How to Fix SI Joint Pain: Tips That Actually Work
The most effective approach combines gentle movement, posture changes, and targeted strengthening. Rest is helpful for a day or two during a severe flare-up, but prolonged rest tends to make the joint stiffer and the supporting muscles weaker.
Start with movement that does not load the joint heavily. Walking on flat ground, swimming, and using an elliptical machine are generally well tolerated. Avoid running, jumping, and high-impact exercise until the pain settles.
Strengthening the muscles around the pelvis is the foundation of long-term improvement. The glutes, core, and hip muscles act as a natural brace for the SI joint. When these muscles are weak, the joint takes more force than it can handle.
Manual therapy can help. Physical therapists, chiropractors, and osteopathic physicians often use hands-on techniques to improve joint mobility and reduce muscle tension. Some people respond well to a pelvic belt, which wraps around the hips and provides external support during activity.
Ice and heat are useful tools. Ice reduces inflammation during an acute flare-up, while heat relaxes tight muscles. Neither fixes the underlying problem, but both can make it easier to move and exercise.
Exercises That Help SI Joint Pain
Certain exercises consistently help people with SI joint pain. The key is to move slowly and stop if the pain increases significantly. Mild discomfort during exercise is acceptable, but sharp or worsening pain is a signal to stop.
A simple glute bridge is a good starting point. Lie on your back with your knees bent and feet flat on the floor. Squeeze your glutes and lift your hips until your body forms a straight line from shoulders to knees. Hold for a few seconds, then lower slowly. Repeat 10 to 15 times.
Bird dogs are another effective exercise. Start on your hands and knees. Extend your right arm forward and your left leg backward simultaneously, keeping your hips level. Hold briefly, then return to the starting position. Alternate sides for 8 to 10 repetitions per side.
Side-lying hip abduction targets the gluteus medius, a muscle that stabilizes the pelvis. Lie on your side with your legs stacked. Lift your top leg slowly, keeping your hips stacked, then lower it with control. Do 10 to 15 repetitions on each side.
Pelvic tilts help with mobility and core activation. Lie on your back with your knees bent. Gently tilt your pelvis so your lower back presses into the floor, then release. Move slowly and breathe normally for 10 to 15 repetitions.
Stretching can also help, especially if the muscles around the joint are tight. A gentle knee-to-chest stretch, a figure-four stretch lying on your back, and a seated spinal twist are commonly recommended. Hold each stretch for 20 to 30 seconds without bouncing.
Posture and Daily Habits That Protect the SI Joint
How you move during the day matters as much as your exercise routine. Small changes in posture and movement patterns can reduce stress on the joint significantly.
Avoid sitting with your wallet in your back pocket. This tilts your pelvis unevenly and can aggravate SI joint pain. Sit with both feet flat on the floor and your weight evenly distributed across both sit bones.
When getting out of bed, roll to your side first, then push yourself up with your arms. Do not sit straight up from a lying position, as this twists the pelvis and loads the SI joint unevenly.
Lifting technique matters. Bend at your knees, keep the object close to your body, and engage your core before lifting. Avoid twisting while carrying heavy loads.
Sleeping position can also affect the joint. If you sleep on your side, place a pillow between your knees to keep your pelvis aligned. If you sleep on your back, a pillow under your knees can reduce strain on the lower back and pelvis.
Medical Treatments for SI Joint Pain
When conservative measures are not enough, medical treatments are available. These range from injections to surgical procedures, and the evidence for each varies.
Physical therapy is the first-line treatment for most people. A physical therapist can assess your specific movement patterns and design a program tailored to your needs. This is more effective than following a generic exercise list from the internet.
Anti-inflammatory medications such as ibuprofen or naproxen can reduce pain and inflammation during a flare-up. These are available over the counter, but long-term use carries risks including stomach irritation and kidney problems. Talk to your doctor about appropriate use.
SI joint injections contain a corticosteroid and a numbing agent. The injection can provide significant pain relief for weeks to months, and it also serves a diagnostic purpose. If the injection relieves the pain, it confirms the SI joint is the source. The evidence for injections is mixed, with some people experiencing lasting relief and others getting only temporary benefit.
Radiofrequency ablation is a procedure that uses heat to disable the nerves that transmit pain from the SI joint. Some studies suggest this can provide relief lasting six months to a year. The procedure is not appropriate for everyone, and success rates vary.
Surgery is the last resort. SI joint fusion is a procedure that permanently fuses the joint to stop it from moving. It is reserved for people with confirmed SI joint pain who have not responded to conservative treatment. The evidence for fusion is limited, and outcomes vary widely. Some people experience significant improvement, while others continue to have pain.
When to See a Doctor for SI Joint Pain
You should see a doctor if the pain is severe, if it follows a fall or injury, or if it does not improve after a few weeks of home care. You should seek urgent medical attention if the pain is accompanied by numbness or weakness in the legs, loss of bowel or bladder control, or fever. These symptoms can indicate a more serious condition that requires immediate evaluation.
Diagnosing SI joint pain requires a thorough examination. Your doctor will likely press on the joint, move your legs in specific positions, and may order imaging such as X-rays or an MRI to rule out other causes. There is no single test that definitively diagnoses SI joint pain, which is why the diagnosis is often based on a combination of exam findings and response to treatment.
Some people with SI joint pain also have a condition called ankylosing spondylitis, an inflammatory arthritis that primarily affects the spine and SI joints. If your pain is worse in the morning, improves with movement, and is accompanied by stiffness that lasts more than 30 minutes, mention this to your doctor. This pattern is characteristic of inflammatory arthritis and may require different treatment.
Frequently Asked Questions
How long does it take to recover from SI joint pain?
Most people see significant improvement within 4 to 6 weeks of consistent conservative treatment. Full recovery can take longer, and some people manage the condition long-term rather than completely eliminating it.
Can SI joint pain go away on its own?
Mild cases can resolve on their own within a few weeks. Persistent or recurrent pain usually requires active treatment such as physical therapy to address the underlying muscle weakness and joint dysfunction.
Is walking good for SI joint pain?
Walking on flat, even surfaces is generally safe and beneficial for SI joint pain. It promotes blood flow and keeps the muscles around the joint active without placing excessive stress on it.
What makes SI joint pain worse?
Prolonged sitting, twisting movements, high-impact exercise, and uneven surfaces typically worsen SI joint pain. Standing on one leg for long periods and climbing stairs can also aggravate the joint.
