I. What is femoral head necrosis
Femoral head necrosis, also known as ischemic necrosis of the femoral head, is a complex pathological process caused by the destruction of the blood supply to the femoral head or the degeneration of bone cells caused by a combination of pathogenic factors, which in turn leads to the death of the viable components of bone (bone cells, bone marrow hematopoietic cells and adipocytes). It is a common and difficult to treat bone and joint disease.
Second, the etiology of femoral head necrosis
The causes of femoral head necrosis are diverse, but the most important and common are the following three major causes.
First, long-term use of hormones. Hormonal osteonecrosis accounts for nearly half of all femoral osteonecrosis during the last 20 years, so this type of femoral osteonecrosis is extremely common in the clinic. There are some patients suffering from immune diseases, such as systemic lupus erythematosus, rheumatoid, dry syndrome, etc. In some cases, hormones must be applied to control the condition. However, some friends blindly believe in the so-called “prescriptions” or “ancestral secret recipes” on the street, which may contain hormones, so they may be able to temporarily relieve the symptoms after using them, but the incorrect dosage and usage of hormones may lead to the problem of femoral head necrosis. Therefore, “hormones” are fiercer than tigers, so when you use hormones or hormone-containing drugs, you must apply them under the guidance of a doctor, and of course, you should not trust the so-called “prescriptions” or “secret recipes”. The “ancestral secret recipe”.
The process of osteonecrosis progresses quickly, and most patients have femoral head collapse about 2 years after the occurrence of femoral head necrosis, so the high disability rate of femoral head necrosis, which seriously reduces people’s quality of life.
Second, long-term alcohol abuse. Alcoholic osteonecrosis of the femoral head is more common in Western countries. Moderate drinking can promote blood circulation, can relieve mental tension, reduce stress-related diseases, especially cardiovascular disease, but if long-term, heavy alcohol abuse can be extremely harmful to our health, such as fatty liver, pancreatitis, memory loss, and of course, we talk about today’s femoral head necrosis, alcohol leads to increased blood viscosity caused by bone microcirculation disorders and femoral head necrosis Alcohol is a double-edged sword. Alcohol is a double-edged sword, we must grasp the “degree”, so for the sake of our health, we suggest that alcoholic friends better quit drinking, and we suggest that the total amount of liquor should not exceed 2 taels per day if there are really difficulties.
Thirdly, hip trauma, the most common of which is femoral neck fracture. Fracture of the femoral neck can directly affect the local blood supply of the femoral head, thus leading to femoral head necrosis. Femoral head necrosis occurs in 1M3 of patients with femoral neck fracture. Patients with femoral neck fracture must go to a regular hospital for treatment in time, without delay, so as not to delay the best time for fracture repositioning. Especially for elderly people over 60 years old, if a fall occurs and there is discomfort in the hip, it is very necessary to go to a nearby hospital to take a hip film so as not to delay the diagnosis and miss the best treatment window.
Third, the diagnosis of femoral head necrosis
Femoral head necrosis is mostly manifested as hidden pain and dull pain in the hip joint or its surrounding tissues, which seriously affects the quality of life and labor ability of patients. The lesions are divided into early and late stages. Because of the mild and insidious symptoms in the early stage, it is easy to be ignored by patients and some doctors. Therefore, many patients are already in the advanced stage of the disease when they are clearly diagnosed, thus losing the best time for early treatment to preserve the femoral head and can only be treated by artificial joint replacement surgery. Therefore, early and correct diagnosis is necessary for patients with osteonecrosis of the femoral head. Early diagnosis of osteonecrosis of the femoral head is not difficult, the key point is that when the patient has symptoms of hip pain and discomfort, he/she should seek medical attention in time, and after the medical history is taken, careful examination and careful analysis by professional doctors, and through appropriate examination, osteonecrosis of the femoral head can be confirmed or excluded. At present, the main examination methods include X-ray, CT, nuclear scan and magnetic resonance examination. Among them, magnetic resonance examination has high sensitivity, especially in the early examination of femoral head necrosis, magnetic resonance examination has high diagnostic value.
Fourth, the staging of femoral head necrosis
The staging of femoral head necrosis is decisive for its treatment. There are many ways of staging femoral head necrosis. But patients are more easily understood or the traditional Ficat staging. There are 4 stages of presentation.
Stage I: normal x-ray presentation
Stage II: normal femoral head appearance, but with significant bone repair manifestations (cystic degeneration and osteosclerosis)
Stage III: collapse of subchondral bone (flattening of the femoral head)
Stage 4: joint space narrowing, joint collapse and secondary degeneration of the acetabulum (cystic degeneration, marginal bone redundancy formation, cartilage destruction)
If the femoral head collapses (stage 3 or 4), it is advanced and can only be treated with artificial hip replacement surgery.
Five, the treatment of femoral head necrosis
(a) Non-surgical treatment
1, braking, including bed and lower limb traction and other measures to reduce or avoid weight-bearing, by reducing the weight of the femoral head to facilitate the repair of the femoral head itself, lower limb traction can reduce the pressure on the surface of the femoral head, the effect is significantly better than simple bed.
2. Pulsed electromagnetic field therapy In the early 1980s, many scholars began to use pulsed electromagnetic field therapy to treat ANFH. Experiments have confirmed that electromagnetic field can slow down the process of femoral head collapse, and it is a pre-surgical treatment option, but there is still a lack of long-term follow-up data, and its mechanism of action needs further study.
Hyperbaric oxygen (HBO) therapy is a non-invasive physical therapy that has been widely used in clinical practice. Numerous studies have shown that HBO combined with other non-surgical or surgical treatments is one of the best choices for early ANFH.
4.Interventional therapy Interventional therapy is to inject thrombolytic, antispasmodic and vasodilatory drugs directly into the blood vessels supplying blood flow to the femoral head, such as the internal and external femoral arteries, under the surveillance of TV x-ray machine, in order to achieve the treatment purpose. Local application of the above drugs can improve the blood supply to the femoral head, lower the intraosseous pressure, promote the resorption of necrotic bone and new bone formation, and create an environment conducive to the repair of the osteonecrotic area. Most of the reported interventional methods are effective in treating ANFH. Most of these studies determine the efficacy in terms of symptoms and angiography, and there are few follow-ups on patient symptoms and long-term outcomes.
(II) Surgical treatment
1.Medullary core decompression plus simple bone grafting Medullary core decompression plus simple bone grafting has achieved better results. The application of bone graft with vascular tip is a treatment method for the pathological changes of ANFH, which can effectively achieve intra-femoral decompression, rapidly restore blood flow in the femoral head, support the weight-bearing area and induce osteogenesis. The efficacy of fibula bone graft with vascular tip is certain for patients with more limited necrotic area and no collapse or collapse of joint surface less than 3mm, but the surgery is complicated, requiring taking own fibula and anastomosis of blood vessels under microscope. The latest tantalum rod implantation can completely replace the autologous fibula and has better clinical efficacy, and our hospital has achieved good results since it was first carried out by me in 2008.
2.Osteotomy The speed of osteonecrosis in ANFH patients exceeds the speed of its repair, and the mechanical properties of the femoral head are significantly reduced, making it difficult to bear normal load. If the necrosis is located in the weight-bearing area, then the femoral head will easily collapse. The principle of osteotomy is to change the negative gravity line of the femoral head by osteotomy, rotating the necrotic zone from the weight-bearing zone to the non-weight-bearing zone, so that the viable bone is in the weight-bearing zone, thus providing a good environment for self-repair. Many patients develop claudication due to the altered length and line of force of the affected limb. Osteotomies also make hip arthroplasty more difficult. Therefore, the indications should be strictly selected, and osteotomy is mainly suitable for young patients with stage I-III.
3. Femoral head surface replacement This method is actually a partial hemispherical surface replacement. The femoral head surface prosthesis is made of cobalt-chromium alloy, and its function is to restore the spherical shape of the femoral head. This method is considered to be a transitional method for total hip replacement in middle and late stage femoral head necrosis. The advantage is that only the degenerated cartilage and subchondral bone of the proximal femur are removed, which has little impact on the acetabulum and is less traumatic. The normal bone of the femoral head neck can be preserved, which does not affect the fusion of the hip or total hip replacement in the long term and postpones the time of total hip replacement; the femoral bone is preserved and the femoral stem is avoided, thus reducing the total amount of foreign body implantation and the chance of infection.
4.Artificial joint replacement Artificial joint replacement includes artificial femoral head replacement and total hip arthroplasty (THA). Artificial femoral head replacement has been abandoned by most scholars because of its short life span, high revision rate and increased difficulty for THA in the future. THA in patients with advanced femoral head necrosis is an accepted and effective option. It can significantly relieve pain and improve joint function.