This joint inflammation can cause pain in the buttocks or lower back. The pain can go down one or both legs.
Sacroiliitis (say-kroe-il-e-I-tis) is a painful condition that affects one or both sacroiliac joints. These joints sit where the lower spine and pelvis meet. Sacroiliitis can cause pain and stiffness in the buttocks or lower back, and the pain might go down one or both legs. Standing or sitting for a long time or climbing stairs can make the pain worse.
Sacroiliitis can be hard to diagnose. It can be mistaken for other causes of low back pain. It's been linked to a group of diseases that cause inflammatory arthritis of the spine. Treatment might involve physical therapy and medicines.
The sacroiliac joints link the pelvis and lower spine. These two joints are made up of the bony structure above the tailbone, known as the sacrum, and the top part of the pelvis, known as the ilium. The sacroiliac joints support the weight of the upper body when standing.
The pain of sacroiliitis most often occurs in the buttocks and lower back. It also can affect the legs, groin and even the feet. The pain can improve with movement. The following can make sacroiliitis pain worse:
Causes for sacroiliac joint issues include:
Sacroiliitis can cause difficulty with certain actions, such as bending, lifting, staying in one position and rising from being seated. The ongoing pain of sacroiliitis can lead to depression and loss of sleep.
During the physical exam, a health care provider might press on the hips and buttocks to find the pain. Moving legs into different positions gently stresses the sacroiliac joints.
An X-ray of the pelvis can show signs of damage to the sacroiliac joint. An MRI can show whether the damage is the result of ankylosing spondylitis.
If putting numbing medicine into the sacroiliac joint stops the pain, it's likely that the issue is in the sacroiliac joint.
Treatment depends on symptoms and the cause of the sacroiliitis. Stretching and strengthening exercises and nonsteroidal antiinflammatory pain relievers you can get without a prescription are often the first treatments used.
Depending on the cause of the pain, these might include:
Biologics. Biologic medicines treat many autoimmune conditions. Interleukin-17 (IL-17) inhibitors include secukinumab (Cosentyx) and ixekizumab (Taltz). Tumor necrosis factor (TNF) inhibitors include etanercept (Enbrel), adalimumab (Humira), infliximab (Remicade) and golimumab (Simponi).
Both types of biologics are used to relieve sacroiliitis.
A health care provider, such as a physical therapist, can teach range-of-motion and stretching exercises. These exercises are designed to ease pain and to keep the low back and hips more flexible. Strengthening exercises help protect the joints and improve posture.
If other methods haven't relieved pain, a health care provider might suggest:
Corticosteroids can be put directly into the sacroiliac joint to reduce swelling and pain. Sometimes, a health care provider puts a numbing medicine into the joint to help make the diagnosis.
Home treatments for sacroiliitis pain include:
You might start by seeing your primary care provider. You might be referred to a specialist in bones and joints, known as a rheumatologist, or an orthopedic surgeon.
Take a family member or friend along, if possible. Someone who's with you can help you remember the information you get.
Make a list of:
For sacroiliitis, questions to ask include:
Ask other questions you have.
Your care provider might ask you questions, such as: