Sacroiliitis is an inflammation of one or both of the sacroiliac joints, which connects the lower spine and pelvis. With sacroiliitis, even the slightest movements of your spine can be extremely uncomfortable or even painful for you.
Sacroiliitis can be difficult to diagnose, and it may be mistaken for other causes of low back pain, including sciatica, herniated disks and strained muscles. Sacroiliitis may be associated with a group of diseases called spondyloarthropathies, which cause inflammatory arthritis of the spine.
Sacroiliitis symptoms may include pain and stiffness in your lower back, thighs or buttocks, pain that worsens with walking because the motion of your hips strains your sacroiliac joints. Pain radiating down your leg, limping, and decreased range of motion.