Sacroiliac joint (SIJ) pain refers to discomfort in the sacroiliac joints, which connect the lower spine to the pelvis. These joints play a crucial role in providing stability to the pelvis and support during movement. SIJ pain can result from various factors, including injury, arthritis, pregnancy, or uneven leg length, which can lead to inflammation and dysfunction in the joint. Symptoms often include localized pain in the lower back, buttocks, and hips, and may worsen with activities such as standing, walking, or climbing stairs. Physical therapy can strengthen and stabilize the surrounding muscles.