Sacroiliac Joint Dysfunction
Pain from the joints linking the spine to the pelvis
Quick Facts
- Type: Musculoskeletal condition
- Location: Sacroiliac joints (base of spine and pelvis)
- Common signs: Low back and buttock pain
- Common triggers: Pregnancy, injury, uneven movement
Overview
The sacroiliac (SI) joints are two strong joints that connect the sacrum, the triangular bone at the base of the spine, to the pelvis on each side. They carry the weight of the upper body and transfer it to the legs, and they normally allow only a small amount of movement. Sacroiliac joint dysfunction refers to pain that arises when these joints move too much, too little, or become inflamed.
SI joint dysfunction is a common but often overlooked cause of lower back and buttock pain. Because the pain can spread to the hip, groin, or leg, it is sometimes mistaken for other back or hip problems. With the right diagnosis, most people improve with non-surgical treatment.
Symptoms
Pain is usually felt low down and to one side, though it can affect both sides.
- Pain in the lower back, buttock, or back of the hip, usually on one side
- Pain that can spread to the groin or down the back of the thigh
- Worse pain when standing up from sitting, climbing stairs, or standing for a long time
- Stiffness or a feeling of the pelvis catching or giving way
- Discomfort when lying on the affected side
Most SI joint pain is not dangerous, but pain with fever, leg weakness, or loss of bladder or bowel control should be evaluated promptly, as these point to other problems.
Causes
SI joint dysfunction can result from too much or too little movement at the joint, or from inflammation.
- Injury: A fall, car accident, or sudden impact through the pelvis.
- Pregnancy and childbirth: Hormonal changes loosen the pelvic ligaments and added weight stresses the joints.
- Uneven loading: A difference in leg length, an altered walking pattern, or arthritis in a nearby joint can stress the SI joint.
- Inflammatory arthritis: Conditions such as ankylosing spondylitis can inflame the sacroiliac joints.
- Wear over time: Age-related changes in the joint cartilage.
Risk Factors
- Pregnancy and recent childbirth
- A previous pelvic or lower back injury
- A difference in leg length or an altered gait
- Inflammatory arthritis affecting the spine and pelvis
- Prior lower spine surgery, which can change how forces pass through the SI joints
Diagnosis
SI joint dysfunction is diagnosed mainly through examination, as it can be hard to distinguish from other causes of back and hip pain.
- Physical exam: The doctor performs specific movements and pressure tests that stress the SI joint to see if they reproduce the pain.
- Imaging: X-rays, CT, or MRI may be used to look for arthritis, injury, or inflammatory disease and to rule out other causes.
- Diagnostic injection: Numbing medicine placed into the joint that temporarily relieves the pain can help confirm the joint as the source.
Treatment
Most people improve with non-surgical treatment aimed at calming pain and improving joint stability.
- Physical therapy: Exercises to strengthen the core, hip, and pelvic muscles and to correct movement patterns.
- Pain relief: Over-the-counter pain relievers, heat or cold, and activity changes.
- Support: A pelvic or SI belt can stabilize the joint, especially during pregnancy or flare-ups.
- Manual therapy: Hands-on techniques may help when the joint moves abnormally.
- Injections: Steroid injections into the joint can reduce inflammation and pain.
- Procedures or surgery: Rarely, when other treatments fail, procedures to calm the joint nerves or to fuse the joint are considered.
Prevention
- Keep the core, hip, and pelvic muscles strong with regular exercise
- Use good posture and safe lifting techniques
- Maintain a healthy weight to reduce load on the pelvis
- Warm up before sports and avoid sudden overloading of the lower back
- Address leg-length differences or gait problems with professional guidance
When to See a Doctor
See a doctor if you have lower back or buttock pain that lasts more than a few weeks, keeps returning, or limits your activities. Seek prompt care if pain is accompanied by:
- Fever or feeling generally unwell
- New leg weakness or numbness
- Loss of bladder or bowel control
- Severe pain after a fall or accident
These additional symptoms suggest a cause other than simple SI joint dysfunction and need timely evaluation.
Frequently Asked Questions
Where is sacroiliac joint pain felt?
It is usually felt in the lower back, buttock, or back of the hip, most often on one side, and can spread to the groin or down the back of the thigh. Pain often worsens when standing up, climbing stairs, or standing for long periods.
What causes sacroiliac joint dysfunction?
Common causes include injury, pregnancy and childbirth, uneven loading from a leg-length difference or altered gait, inflammatory arthritis such as ankylosing spondylitis, and age-related wear. Too much or too little joint movement can both cause pain.
How is SI joint dysfunction diagnosed?
Diagnosis relies mainly on a physical examination with movements and pressure tests that stress the joint. Imaging helps rule out other causes, and a numbing injection that temporarily relieves the pain can confirm the joint as the source.
Can sacroiliac joint dysfunction be treated without surgery?
Yes. Most people improve with physical therapy, exercise, pain relief, a supportive belt, and sometimes steroid injections. Surgery is rare and reserved for cases that do not respond to other treatments.
Is sacroiliac joint pain related to pregnancy?
Pregnancy is a common trigger. Hormones loosen the pelvic ligaments and the added weight stresses the SI joints, which can cause pain during and after pregnancy. A supportive belt and targeted exercises often help.
References
- MedlinePlus, U.S. National Library of Medicine. Sacroiliac joint pain.
- Mayo Clinic. Sacroiliitis.
- National Library of Medicine, StatPearls. Sacroiliac Joint Dysfunction.
- American Academy of Orthopaedic Surgeons. Sacroiliac joint pain.