Type IB hip is a congenital or acquired cause of abnormal hip joint development, resulting in deformities such as shallow and flat acetabulum, increased anterior femoral diameter and straightened neck stem angle, which will eventually lead to hip instability and hip dislocation, and in severe cases, hip osteoarthritis may occur. The clinical manifestations are hip pain, abnormal gait and muscle atrophy of the lower limbs, and if one side develops, the lower limbs may be unequal. In terms of treatment, patients less than 12 years old can undergo internal pelvic osteotomy, while other patients can undergo biphasic osteotomy and triphasic osteotomy, all with the aim of increasing acetabular coverage and improving hip joint stability. Adults who have hip pain that seriously affects their life and work can undergo artificial total hip replacement surgery.