Sacroiliitis is a painful condition that affects one or both sacroiliac joints, which sit where the lower spine meets the pelvis. In my practice, I often see patients who think they have only “ordinary low back pain,” but when I evaluate them carefully, the real source of pain may be the sacroiliac region. Because this condition can mimic other spine, hip, or nerve problems, it is often misunderstood or diagnosed late. [1]
One important point I want Bangladeshi patients to understand is that sacroiliitis is not a single disease. It is a description of inflammation or irritation in the sacroiliac joint area. The underlying reason may be inflammatory arthritis, mechanical stress, pregnancy-related strain, injury, infection, or sometimes wear-and-tear changes. [1][2]
In Dhaka and other parts of Bangladesh, many people delay assessment because they are busy, have long travel times, or assume persistent back and buttock pain will go away on its own. That delay can make daily movement, sleep, prayer positions, work duties, and family responsibilities more difficult. Early evaluation matters, especially when pain is persistent, inflammatory in pattern, or associated with fever, weakness, or other warning signs. [1][3]
What Is the Sacroiliac Joint?
The sacroiliac joints connect the sacrum, which is the triangular bone at the bottom of the spine, to the iliac bones of the pelvis. These joints help transfer body weight from the upper body to the legs and provide stability during standing, walking, bending, and turning. [1]
Although movement in these joints is limited, even a small amount of inflammation or mechanical irritation can cause significant discomfort. Patients often describe the pain as deep, aching, or sharp in the lower back, buttock, or back of the hip. Sometimes the discomfort may spread into the groin or thigh, which is why it can be confused with hip disease, sciatica, or muscle strain. [1][2]
Common Symptoms of Sacroiliitis
The symptoms of sacroiliitis can vary from person to person. I usually explain to my patients that the pattern of pain is often more important than the pain alone.
Pain Location
The most common symptoms include:
- pain in the lower back
- pain in one or both buttocks
- stiffness around the pelvis
- discomfort after sitting for a long time
- pain while standing up, climbing stairs, or walking for a long distance
Some patients feel worse after prolonged rest, especially early in the morning. Others notice more pain when turning in bed, standing on one leg, or getting up from a low chair. [1][2]
Inflammatory Pattern
When sacroiliitis is related to inflammatory conditions such as axial spondyloarthritis or ankylosing spondylitis, the pain may be worse after rest and improve somewhat with movement or exercise. Morning stiffness lasting a long time is another clue. [2][4]
Mechanical Pattern
When the problem is more mechanical, pain may become worse with repeated standing, lifting, uneven walking, pregnancy-related stress, or poor movement patterns. In Bangladesh, I also think about long commuting hours, road vibration, heavy household work, and delayed access to physiotherapy, because these practical realities can aggravate symptoms.
What Causes Sacroiliitis?
There are several possible causes, and proper treatment depends on identifying the most likely one.
Inflammatory Arthritis
This is one of the most important causes. Ankylosing spondylitis and related spondyloarthritis conditions can inflame the sacroiliac joints and cause chronic pain and stiffness. Some patients may also have psoriasis, inflammatory bowel disease, or eye inflammation such as uveitis. [2][4]
Injury or Mechanical Stress
A fall, road traffic injury, twisting movement, or repeated strain can irritate the sacroiliac joint. In some people, the problem develops gradually rather than after one obvious injury. [1]
Pregnancy and Postpartum Strain
Pregnancy changes posture, joint flexibility, and weight distribution. The sacroiliac joints can become stressed during pregnancy and childbirth, and some women continue to feel pain afterward. This is especially important in local settings where new mothers may resume household demands early and have limited rehabilitation support. [1]
Degenerative Change
Age-related joint wear, altered gait, hip stiffness, or lumbar spine problems can also overload the sacroiliac joint area. Sacroiliac pain is sometimes part of a broader mechanical chain involving the hip, pelvis, and lower back.
Infection
Although uncommon, infection of the sacroiliac joint is serious. Fever, severe pain, inability to bear weight, or significant worsening over a short period should never be ignored. [1][5]
How Sacroiliitis Is Diagnosed
Sacroiliitis is not diagnosed from one symptom alone. When I evaluate patients with this problem, I combine the history, physical examination, and when necessary, imaging or laboratory tests.
History Taking Matters
I pay close attention to:
- how long the pain has been present
- whether the pain is worse at rest or with activity
- whether there is morning stiffness
- whether there was injury, pregnancy, fever, skin disease, bowel symptoms, or eye inflammation
- whether there is a family history of inflammatory arthritis
This history helps separate inflammatory pain from mechanical pain.
Physical Examination
A careful examination can reproduce pain around the sacroiliac joint with specific movement tests. I also check the lower back, hips, gait, posture, flexibility, and nerve function because many conditions can overlap.
