Osteonecrosis of the femoral head, which causes the collapse of femoral head and secondary osteoarthritis of the hip joint, leads to premature total hip arthroplasty in young patients. Nonunion of long bone still often presents a dilemma in achieving a bony union. Stem cell treatment may provide an innovative therapy for these lesions. Unlike bone, which is self-regenerating tissue, articular cartilage has limited potential for self-regeneration, and damage to articular cartilage has limited potential for self-regeneration, and damage to articular cartilage eventually leads to the development and progression of osteoarthritis.