The etiology of femoral head necrosis is diverse (about 60 types) and complex, making it difficult to classify it comprehensively and systematically, which is related to the unclear pathogenesis. Here, we only need to introduce hormonal osteonecrosis of the femoral head, that is, medication causing osteonecrosis of the femoral head. For example, long-term use of hormonal drugs due to bronchitis, asthma, rheumatism, rheumatoid, neck, shoulder, back and leg pain, diabetes, skin disorders, etc. It is an early statement that the accumulation of hormones in the organism due to the large amount or long-term use of hormones has led to the development of the disease. Recently, it is believed that the occurrence of femoral head necrosis is directly related to the type, dosage form and route of administration of hormones, and is not directly proportional to the total amount and time of hormone application. However, the long-term use of large amounts of hormones or excessive daily doses, and sudden changes in dose increases and decreases are also one of the reasons for the occurrence of femoral head necrosis. Hormonal necrosis of the femoral head is common with bilateral onset, and more than half of the patients have the onset on one side first, and after several months or years, the other just developed. The clinical manifestations are hip pain, swelling, dizziness, chest tightness, and limited function of lower limbs.
The treatment and prevention methods mainly focus on the possible causes and pathogenesis, such as reducing the dose of hormones, preventing and controlling osteoporosis, activating blood circulation, reducing intraosseous pressure and improving local blood circulation. Collectively, there are two main categories of conservative treatment and surgical treatment.
1.Conservative treatment.
Conservative treatment is mainly adapted to early patients with undeformed femoral head. Conservative treatment can only be considered as always care and health care, and cannot be considered as a treatment method, so conservative treatment does not play the role of treating femoral head necrosis. Its methods include.
(1) Reduce hormone dosage as much as possible: for those who are expected to need a larger dose of hormone for more than 3 months, immunosuppressants should be added as much as possible to reduce the hormone dosage as early as possible to prevent the emergence of adverse reactions such as femoral head necrosis.
(2) Restriction of weight bearing, bed rest and traction, hip herringbone cast fixation, etc.: to facilitate the healing and reconstruction of femoral head necrosis, but the effect of the treatment method of avoiding weight bearing alone is not ideal, and the success rate is less than 15%, which is mainly suitable for femoral head necrosis with lesions located on the medial side of the femoral head.
(3) Prevention and control of osteoporosis: adequate supplementation of calcium and vitamin D, use of some drugs for osteoporosis such as calcitonin or alendronate, etc.
(4) Lipid-lowering drugs and anticoagulants: Some studies reported that the occurrence of osteonecrosis was significantly reduced when statins (lovastatin, fluvastatin, atorvastatin, etc.) were used in combination with hormones, suggesting that statins can prevent the occurrence of osteonecrosis.
(5) Physiotherapy: mainly through the thermal effect or mechanical stress on bone tissue or cells after the action, causing potential changes and cavitation effect, etc., activating cells and tissues, activating cell proliferation, promoting tissue growth, thereby improving local blood circulation. Physical therapy includes shock wave, ultra-short wave, fractional meter wave, electrical stimulation and other treatment methods.
(6) Interventional therapy: Interventional therapy is the direct injection of thrombolytic, anticoagulant, vasodilator and Chinese medicine into the blood supply arteries of the femoral head, such as the internal and external femoral arteries and the closed artery, or cannula perfusion with the injection of bone growth promoter in the local necrotic area, in order to expand the blood vessels in the femoral head area, dissolve fat emboli, unblock the microcirculation of the femoral head, improve the local blood supply, promote the growth of new bone and repair the necrotic femoral head.
(7) Hyperbaric oxygen therapy: to promote femoral head repair by increasing the partial pressure of blood oxygen and improving bone cell hypoxia.
(8) Stem cell therapy: bone marrow mesenchymal stem cells are stem cells with multi-directional differentiation potential derived from the mesoderm, which mainly exist in connective tissue and organ mesenchyme throughout the body, with the most abundant in bone marrow tissue. After isolated and cultured in vitro, bone marrow MSCs have the ability to differentiate into osteoblasts, chondrocytes, neuronal cells, adipocytes, cardiomyocytes, etc. under certain induction conditions. It promotes early microcirculation reconstruction, thus enhancing blood supply and creating a microenvironment for vascular regeneration, which contributes to early repair of ischemic necrotic area of femoral head. At present, stem cell therapy is only applied to early stage of femoral head necrosis, and the long-term efficacy needs to be further observed. Stem cell therapy has important research and application prospects, but its induction differentiation process and related mechanisms need further research.
(9) Traditional Chinese medicine treatment: Su et al. used 20g each of Radix Rehmanniae, Cornus officinalis and Fructus Lycii, 15g each of Radix Rehmanniae, Herba Cistanches and Rhizoma Bone, 10g each of Radix Zedoariae, Rhizoma Yam, Herba Epimedium, Radix Paeoniae, Rhizoma Polygonati, Dampness of Liver and Kidney, 25g each of Radix Astragali, Radix Angelicae Sinensis and Rhizoma Chuanxiong, 30g of Salviae Miltiorrhizae and 5g of Glycyrrhiza glabra. The treatment is divided into 6 types: Qi stagnation, blood stasis, wind-cold dampness, phlegm-dampness, qi-blood deficiency, liver-kidney yin deficiency and spleen-kidney yang deficiency.
2.Surgical treatment.
Surgery is the main method of treatment for ischemic necrosis of the femoral head in the middle and late stages, but surgery is not suitable for all the people, surgery for necrosis of the femoral head has a large risk, high cost and other disadvantages. Moreover, the femoral head has to be replaced every few years after surgery, so even if we don’t consider the cost, we have to consider whether the patient’s body can bear it.
(1) Medullary core decompression + simple bone grafting: At present, simple medullary core decompression of the femoral head (because it can accelerate the collapse of the femoral head) is used less often, and medullary core decompression + simple bone grafting is generally used, which has become a popular treatment for ischemic necrosis of the femoral head because it not only removes the necrotic bone but also reduces the intraosseous pressure, and provides limited mechanical support at the same time.
(2) Marrow core decompression + vascular bundle implantation or bone grafting with blood transport: Although marrow core decompression plus simple bone grafting achieves better efficacy, the implanted bone has no blood transport and the vast majority of the bone may become necrotic. In order to solve the blood transport of the transplanted bone, vascular bundle implantation or iliac flap with vascular tip and vascular bundle implantation or large bone flap with vascular tip or with myotis plus vascular bundle implantation with dead bone removal is used to achieve good results.
(3) Osteotomy: The principle of osteotomy is to change the line of gravity of the femoral head through osteotomy, rotating the necrotic area from the weight-bearing area to the non-weight-bearing area to create conditions for its repair. The efficacy of osteotomy has been improved through continuous improvement.
(4) Periosteal transplantation: Some people have designed iliac periosteal transplantation with deep iliac vessels to treat ischemic necrosis of the femoral head, and its blood supply implantation is reliable, which can rebuild the blood circulation of the femoral head and fundamentally reduce the intraosseous pressure. The inner layer cells of the tipped periosteum can differentiate into osteoblasts, which has a positive effect on the repair of femoral head necrosis.
(5) Femoral head surface replacement and femoral head resurfacing: For patients with severe subchondral bone collapse in advanced stages, femoral head replacement, bipolar artificial femoral head replacement and artificial total hip replacement can be chosen, but these methods have high incidence of late joint loosening, prosthesis sinking and many complications. Therefore, some people have used femoral head resurfacing treatment to achieve better results and believe that femoral head resurfacing surgery can replace femoral head hemispheric replacement, bipolar femoral head replacement and total hip replacement, which is especially suitable for adolescents.