Sacroiliac joint dysfunction is a condition that causes pain in the lumbar spine. The sacroiliac joint is a structure that connects the spine and the pelvic girdle and is located between the joint surface of the os ilium and the sacral joint surface. Its position significantly affects the biomechanics of movement and its primary function is to absorb and transmit force from the spine to the pelvic girdle. In addition, it is also responsible for facilitating childbirth in women. Dysfunction of the sacroiliac joints causes pain in the area of the sacroiliac joints and glutes, but it can also spread to the hip area, the back of the upper leg or the spine. It most often develops in athletes and the elderly. The most common mechanism of injury to the sacroiliac joints is a combination of axial load and sudden rotation. There are two primary mechanisms of dysfunction in the sacroiliac joints, namely hypermobility and hypomobility. Other mechanisms of sacroiliac dysfunction can be intra-articular and extra-articular. In addition to etiological sources, there are numerous factors that can predispose a person to the gradual development of dysfunction of the sacroiliac joints. The treatment and diagnosis of dysfunction is one of the most challenging problems faced by doctors, therefore various types of therapy are applied, including intra-articular injections, physiotherapy exercises, manual therapy, orthoses and surgical treatment as a last option.