Dislocation of the hip joint in children with cerebral palsy is caused by excessive stiffness of the surrounding muscles, which causes the femur to dislocate posteriorly and laterally. The age at which dislocation occurs varies widely, and it can occur even at a young age of 2 to 3 years. It is known that the frequency of dislocation increases particularly when standing or walking is delayed or when the child spends a lot of time lying down. Cerebral palsy is a complex syndrome clinically defined, not by a pathological mechanism, and thus, the reported frequency of subluxation and dislocation varies widely depending on the authors (ranging from 3 to 59%, with reports up to 60-80% in severe cerebral palsy), making it one of the most common musculoskeletal complications in children with cerebral palsy, following foot deformities. Subluxation and complete dislocation often require surgical correction of the musculoskeletal system, and even after surgery, ongoing physical therapy is necessary. In children with GMFCS IV cerebral palsy, the risk of dislocation is approximately 3.9% per year, while in those with GMFCS V, it is 9.5%, so a dislocation test using X-rays is recommended every 6 months as a major clinical guideline.