Ms. Huang called to ask: I am 35 years old and always have pain on the inside of my knee. Your doctor diagnosed femoral head necrosis and recommended surgery, why is knee pain diagnosed as hip disease? What are the surgical treatment methods for femoral head necrosis? Doctor’s answer: Patients with osteoarthrosis of the hip joint often complain of medial knee pain in the lower limbs. This is because the nociceptive conduction nerve of the hip shares a common conduction pathway with the knee joint, which is called the closed foraminal nerve. The brain center misinterprets pain messages from the hip as coming from the knee, so clinically patients with hip disorders can experience knee pain. The surgical treatment of femoral head necrosis includes the following. The first is central decompression, which mainly serves to interrupt this vicious cycle, reduce the pressure in the femoral head and promote the regeneration of blood vessels in the femoral head. The second is bone grafting, which promotes bone healing, shortens weight-bearing restrictions, and prevents bone collapse. Bone grafting combined with central decompression surgery is the ideal treatment for early femoral head necrosis. Third, bone grafting with blood supply (bit) can accelerate the regeneration of blood vessels in the femoral head and block further development of necrosis. Fourth, vascular bundle implantation, which can regenerate the necrotic femoral head, is only applicable to the early stage of femoral head necrosis. Fifth, allograft cartilage grafting, which is suitable for patients aged 16 to 50 years, can reduce or eliminate painful symptoms and delay the time of hip joint replacement. Sixth is osteotomy, which is based on the principle of removing the necrotic part of the femoral head from the main weight-bearing area and having the normal part of the femoral head support the weight-bearing area of the acetabulum. However, it tends to destroy the anatomical form of the proximal femur, which makes it more difficult to perform hip replacement again and affects the efficacy. Seven is hip replacement, including hemi hip replacement, surface replacement and total hip replacement. For patients with advanced femoral head necrosis, hip replacement can relieve hip pain and restore hip function.