Introduction
Sacroiliac joint pain is pain felt in the groin, leg, and lower back due to dysfunction of the sacroiliac or SI joint.
The sacroiliac joint connects the hip bones to the spine. The iliac bones of the hip joint with a part of the spine called the sacrum, a triangular bone just above the tailbone. This joint acts as a shock absorber between the upper body, the pelvis, and legs.
Causes
Sacroiliac joint pain may be associated with various conditions including:
- Spine deformities such as scoliosis or kyphosis.
- Unequal leg length
- History of lower back surgery
- Pregnancy or recent childbirth
- Sacroiliac joint injury or trauma
These conditions may cause inflammation of the sacroiliac joint called sacroiliitis which is the main cause of the pain.
Signs and Symptoms
Sacroiliac joint dysfunction may cause pain in and around the hip joint and groin, buttocks, lower back, or side of the thigh. It usually increases with running or jogging. You may have difficulty climbing stairs and bending.
The pain may be associated with:
- Stiffness and reduced range-of-motion of the lower back, hips, and groin
- Instability in the pelvis or lower back
Diagnosis
Your doctor will review your symptoms and medical history. A physical examination of the lower back, hip joint, and legs is performed. The following tests help identify the sacroiliac joint as the source of pain:
- Palpation test: Deep thumb pressure is applied over the entire SI joint to see if pain can be reproduced.
- Distraction test: Pain is elicited when pressure is applied to the front of the hips while lying on your back.
- Sacral thrust test: Pressure is applied to the back of the hips while lying face down.
- FABER test: You will lie on your back with one leg kept straight while the other is bent with the foot across the straight knee. Pressure is applied to the SI joint by gently pushing the bent knee down and out.
- Sacroiliac joint injection: Also called a sacroiliac joint block, this test involves injecting a numbing solution into the sacroiliac joint. If the injection relieves pain, the sacroiliac joint may be confirmed as the pain source. This test is considered most definitive.
Your doctor may also order imaging tests such as X-rays, CT, or MRI scans.
Treatment
Sacroiliac joint pain can be treated through any of the following approaches:
- Brief rest period of 1 to 2 days
- Application of ice or heat in the lower back and pelvis
- A pelvic brace to stabilize the sacroiliac joint
- Pain relief with over-the-counter or prescription medications
- Sacroiliac joint injections to reduce pain and inflammation
- Physical therapy including manual manipulation of the hip and lower back by a specialist
If pain is persistent or severe despite these treatments, your doctor may recommend surgery to fuse the bones of the sacroiliac joint.
Summary
Sacroiliac joint pain may be experienced in the buttock, lower back, hip, groin, or leg. The common causes include developmental deformity of the leg or spine and injury to the sacroiliac joint due to trauma or spine surgery. Pregnancy and childbirth may cause sacroiliac joint pain in women. The pain may be accompanied by stiffness and a reduced range of motion. You may have difficulty climbing stairs, bending, running, and jogging. Your doctor may perform specific tests to identify the source of the pain. Sacroiliac joint pain may be treated by rest, ice or heat application, medications, sacroiliac joint injections, or surgery to fuse the joint. To learn more, speak with your hip specialist.