Femoral head necrosis

Introduction to femoral head necrosis Femoral head necrosis is a disease in which the blood supply to the femoral head is interrupted or damaged, causing death and subsequent repair of bone cells and bone marrow components, which in turn leads to structural changes in the femoral head, collapse of the femoral head, and joint dysfunction. Osteonecrosis of the femoral head (ONFH), also known as avascular necrosis (AVN), is a common refractory disease in the field of orthopedics. ONFH can be divided into two major categories of traumatic and non-traumatic. The former is mainly caused by hip trauma such as femoral neck fracture and hip dislocation. The main reason for the latter is corticosteroid application and alcohol abuse. basic knowledge The proportion of illness: 0.03% (8-10% probability of illness over 50 years old) Susceptible people: no specific population Mode of infection: non-infectious Complications: osteoarthritis

Cause of femoral head necrosis

The causes of femoral head necrosis are diverse (about 60 types), which are complicated and difficult to systematically classify. This is related to the unclear pathogenesis. We have summarized more than ten common types in long-term theoretical research and clinical diagnosis and treatment. The pathogenic factors (below), although the etiology is different, but their common pathological manifestations are femoral head ischemia, a relatively well-recognized theory is that the blood supply is blocked.

Trauma causes femoral head necrosis (30%):

Such as external impact caused by femoral neck fracture, hip dislocation, hip contusion, etc., trauma is the main cause of femoral head necrosis, but the occurrence of traumatic avascular necrosis of the femoral head, the size depends mainly on the degree of vascular damage and The compensatory capacity of the collateral circulation, undoubtedly, due to various traumas, the ruptured tube of the intravascular or femoral head vessels and the distortion or compression can cause necrosis of the femoral head. The clinical manifestations are trace fractures, the head is subluxation, and the lower limbs are muscles. Atrophy, lameness, weight-bearing pain, etc.

Drugs cause femoral head necrosis (25%):

Such as due to bronchitis, asthma, rheumatism, rheumatoid, neck and shoulder pain, diabetes, skin diseases, etc., and long-term use of hormone drugs, due to large or long-term use of hormones, resulting in the accumulation of hormones in the body, this It is an early saying that the occurrence of necrosis of the femoral head has recently been directly related to the type, dosage form and route of administration of the hormone, and is not directly proportional to the total amount and time of the form, but long-term use of hormones or daily doses. Too large, dose increase and decrease mutations are also one of the causes of femoral head necrosis. The hormonal femoral head necrosis is common in both sides, and more than half of the patients have the first side of the disease, after several months or years, another Just onset, the clinical manifestations of hip pain, edema, long dizziness, chest tightness, limited limb function.

Alcohol stimulation leads to necrosis of the femoral head (18%):

Chronic alcoholism is an important factor in various causes of femoral head necrosis. Alcohol accumulation in the body due to long-term heavy drinking causes blood lipids and liver function damage, and blood lipids rise, causing blood. Increased viscosity, slowed blood flow, changes blood coagulability, which can cause vascular occlusion, bleeding or fat embolism, causing osteonecrosis, clinical manifestations of increased weight after drinking, walking duck steps, heart failure, fatigue, abdominal pain, Nausea and vomiting.

1. Abnormal bone marrow hyperplasia leads to osteonecrosis, which is characterized by cold limbs, soreness, inability to bear weight, easy fracture, and obvious atrophy of the bone.

2. Bone tuberculosis with osteonecrosis, manifested as positive tuberculosis test, low fever in the afternoon, pain has a fixed position, weight loss, night sweats, fatigue and so on.

3. Osteonecrosis after surgery, bone transplantation in the clinical stage, three years after vascular transplantation, osteonecrosis occurs due to insufficient supply of bone blood.

4. Wind, cold, and wet cause femoral head necrosis. The clinical manifestations are hip pain, cold and dampness, and difficulty in squatting.

5. Liver and kidney deficiency lead to necrosis of the femoral head, manifested as body weight loss, facial yellow, impotence, premature ejaculation, dreams, nocturnal emission, fatigue and so on.

7. Flat hip causes osteonecrosis. The clinical manifestations are walking duck steps, short limbs, muscle atrophy, pain gradually worsening around 50 meters, and function is limited.

In addition, there are barometric, radioactive, hematological, and vascular diseases.

Among the above factors, local trauma, abuse of hormonal drugs, excessive femoral head necrosis caused by excessive drinking, the common core problem is the blood circulation disorder of the femoral head caused by various reasons, leading to bone cell ischemia, degeneration , necrosis.

Femoral head necrosis prevention

Functional exercise of femoral head necrosis

After the patient is diagnosed with femoral head necrosis, the doctor will limit the weight of the affected limb, rest in bed, perform surgery or non-surgical treatment. In non-surgical therapy, it takes 1 to 3 years for the femoral head necrosis to be repaired. It takes only half a year to repair the fast, but it is not easy to implement and not advocate for long-term heavy bed rest. Functional exercise can prevent disuse of muscle atrophy, which is an effective means to promote early recovery. Functional exercise should be automatic. Mainly, passive supplemented, from small to large, from small to large, gradually increased, and according to the period of avascular necrosis of the femoral head, shape, functional limitations of the soft tissue around the hip joint and physical fitness, choose the appropriate sitting, stand , lying position exercise method.

1 seated legal: sitting on a chair, hands on knees, feet and shoulders, width, left leg to the left, right leg to the right while fully outreach, adduction, 300 times a day, divided into 3-4 times.

2 standing leg raising method: hand support, the body keeps vertical, raises the leg, so that the body and the thigh are at right angles, the thigh and the calf are at right angles, the action is repeated, 300 times a day, divided into 3-4 times.

3-legged leg raising method: supine, lift the affected leg, make the big and small legs in a straight line, and form a right angle with the body, the action is repeated, 100 times a day, divided into 3-4 times.

4 The method of supporting the lower body: holding the fixed object, the body is upright, the feet are separated, and then stand up after the lower jaw, the action is repeated, daily times, divided into 3-4 times.

5 internal rotation and abduction method: hand-held fixation, legs to do full internal rotation, abduction, circular motion, 300 times a day, divided into 3 - 4.

6 Adhere to the training or cycling exercise of the crutches.

Prevention of femoral head necrosis

1 For the femoral neck fracture, strong internal fixation is used. At the same time, bone grafting with vascular pedicled bone can be used to promote the healing of the femoral neck, increase the blood supply to the head, prevent osteonecrosis, and should be followed up regularly after surgery. Calcium to prevent the occurrence of ischemic femoral head.

2 Because the relevant diseases must be applied with hormones, we must master the principle of short-term and appropriate amount, and cooperate with vasodilators, vitamin D, calcium, etc., do not listen to the doctor's advice and abuse hormone drugs.

3 should change the bad habits of long-term alcohol abuse or abstain from alcohol, get rid of the contact environment of pathogenic factors, remove the chemical toxicity of alcohol, and prevent tissue absorption.

4 For occupational factors such as deep-water divers, high-altitude pilots, personnel in high-pressure working environment should pay attention to labor protection and improve working conditions. Those who have already had diseases should change their types of work and seek medical treatment in time.

5 diet should be done: do not eat pepper, but drink alcohol, do not eat hormone drugs, pay attention to increase the intake of calcium, eat fresh vegetables and fruits, more sun, prevent weight, regular activities and other necrosis of the femoral head It has a preventive effect.

Femoral head necrosis complications Complications osteoarthritis

Because of the complicated pathological process of femoral head necrosis, if the early and ineffective treatment can not be obtained, the femoral head will collapse, the joint space will be narrowed, and finally the osteoarthritis will be caused, causing the patient's hip joint dysfunction and causing paralysis. While suffering from physical ailments, patients suffer from psychological trauma and add a heavy burden to families, units and society.

Symptoms of femoral head necrosis Common symptoms Muscle atrophy, trochanter, pain, cyst, joint pain, dull pain, thigh muscle atrophy, tibia, pain, flexion and extension, unfavorable osteoporosis, squat difficulty

The main symptoms of femoral head necrosis are shown in the following five points:

1 pain, pain can be intermittent or persistent, increased after walking, sometimes for rest pain, pain is mostly acupuncture-like, dull pain or soreness, etc., often to the groin area, the inner thigh, the back of the hip and the inside of the knee Radiation, and there is numbness in the area.

2 joint stiffness and limited mobility, suffering from hip joint flexion and extension is unfavorable, squat difficulty, can not stand for a long time, walking duck steps, early symptoms are abduction, external rotation activity is limited.

3 , for progressive short claudication, due to hip pain and femoral head collapse, or late hip subluxation, intermittent claudication often occurs early, especially in children.

4 signs, local deep tenderness, tenderness of adductor muscles, positive test of 4 words, positive gamma s sign, positive test of A11is positive TKdeleuq, abduction, external or internal rotation restricted, affected limb can be shortened Muscle atrophy, and even semi-dislocation signs, sometimes axial pain positive.

5X line performance, small or broken bone texture, cystic femoral head, hardened, flat or collapsed.

Type of femoral head necrosis

The classification of femoral head necrosis is divided into six categories according to the size and shape of the necrotic site, as follows:

1 femoral head is necrotic, less common, which means that the femoral head is completely necrotic from the edge of the joint, and the subfamily femoral neck fracture can often cause full head necrosis.

2 femoral cone (wedge) necrosis, the most common, the normal femoral head is divided into the central weight-bearing area and the inner and outer non-pressure area, the head center cone necrosis is the weight-bearing area osteonecrosis.

The femoral head necrosis of the three femoral heads was high, the osteonecrosis occurred in the anterior upper part of the femoral head, and the dead bone was half-moon-shaped. The X-ray photograph of the hip frog-type outreach position was the most clear.

4 femoral bone necrosis, the lightest, this type generally does not collapse the femoral head.

5 core bone necrosis.

6 non-vascular osteonecrosis.

Staging of femoral head necrosis

The occurrence, evolution and outcome of osteonecrosis have regular pathological processes, that is, necrosis occurs. A dead bone is absorbed and a new bone is formed. X-ray findings, regardless of the size of necrosis, single or multiple, are the epitome of this process. There are many X-ray staging methods for bone necrosis, but we generally use the five-stage method of Arlet, Ficat and Hageffard:

Stage I (pre-radiation period) About 50% of patients in this period may have mild hip pain, which is aggravated when weight-bearing. Physical examination: limited hip joint activity, the earliest occurrence of internal rotation limitation, and increased hip pain during strong internal rotation X-ray shows that it can be negative, and it can also be seen that the scattered osteoporosis or trabecular bone boundary is blurred.

Stage II {necrosis formation, head anterior flattening period) clinical symptoms are obvious, and worse than stage I, X-ray film shows: extensive osteoporosis of the femoral head, scattered sclerosis or cystic changes, trabecular bone disorder, interruption, partial necrosis Area, joint space is normal.

The clinical symptoms of stage III (transitional period) continued to increase. X-ray films showed that the femoral head was slightly flattened, collapsed within 2 mm, and the joint space was slightly narrowed.

Stage IV (collapse period) has severe clinical symptoms, limited limb function, pain relief or disappearance, muscle atrophy of the affected limb, X-ray film shows: external contour of the femoral head and trabecular bone disorder, interruption, half-month sign, collapse More than 2mm, there is dead bone formation, the head becomes flat, and the joint space is narrowed.

The clinical symptoms of stage V (osteoarthritis) are similar to those of osteoarthritis. The pain is obvious and the range of joint activity is severely limited. X-ray films show: femoral head collapse, marginal hyperplasia, joint space fusion or disappearance, hip subluxation, Correct diagnosis and staging are closely related to determining the treatment and treatment effect. Early treatment can prevent the femoral head of osteonecrosis from collapsing. If bone necrosis is found or suspected on the X-ray, magnetic resonance imaging (MRI) can be continued. CT scan, but the above two examinations are more expensive, so it is generally recommended that patients take a pelvic orthotopic X-ray film, or add bilateral X-ray films, hips to 90 ° outreach hip joints.

Femoral head necrosis

Physical examination: observe the patient's gait, check the range of hip joint movement, measure the length and circumference of the lower limbs, local tenderness of the hip joint, do the "4" test of the lower limbs, the Tomar's sign, the Alice sign And sniper test.

Auxiliary examination: patients taking X-ray films can see the femoral skull trabeculae, there may be osteoporosis, uneven bone density, cystic changes, collapse, deformation, or narrow joint space. However, the X-ray film is relatively rough, and the early symptoms of femoral head necrosis are not obvious on the film. It is not easy to diagnose. At this time, CT, MRI, etc. can be used to see the rough and localized capsule on the femoral head. Change, etc., are symptoms of femoral head necrosis.

Diagnosis and diagnosis of femoral head necrosis

According to medical history, clinical symptoms, signs and pelvic orthotopic X-ray films, MRI, CT, etc., can accurately diagnose and prevent femoral head collapse early, is the key to the treatment of femoral head necrosis, however, due to the current specialization of femoral head necrosis research There are not many scientific and technical personnel, and there are few monographs in this area. Therefore, people have not fully defined and paid attention to the etiology, pathology and diagnosis of the disease.

Early diagnosis of femoral head necrosis

1, the patient has hip pain (sore, pain), can be involved in the groin, the anterior medial thigh, the front of the knee, increased after the activity, limp, limited mobility, lower limb weakness, need to be alert to femoral head necrosis.

2. For suspicious cases, the hip joint and the frog-type X-ray film must be taken first. If there is no abnormality, it should be closely observed, or further CT, MRI, ECT, intraosseous pressure measurement, arteriovenous angiography, etc.

3, patients with femoral neck fracture should be followed up to 3-5 years after injury, if the femoral neck height decline, nail marks and cystic changes, and clinical symptoms, should consider this disease.

4. For all patients with low back and leg pain, the hip joint function should be routinely examined during physical examination. If the hip joint abduction is found and the internal rotation is limited, the presence of the disease should be suspected.

5, for the high-risk group of femoral head necrosis need to be vigilant, all adults aged 20-50, groin or hip pain, and discharge to the thigh (or hip pain after one side of the knee pain), slowly progressive, The pain at night is obvious. If the general drug treatment is ineffective, and there is a history of trauma or alcohol abuse or a history of applied hormones or other causes and diseases that cause femoral head necrosis, the disease should be considered first.

Femoral head necrosis diagnosis and treatment standard

Medical history

1. The hip joint has a history of obvious trauma;

2, the history of the use of hormone drugs;

3. Have a long history of alcohol abuse;

4. History of genetics, development, metabolism, etc.;

5, idiopathic (non-invasive).

symptom

1. Progressive hip pain, increased when standing or walking.

2. The first symptoms were hip pain, lumbosacral pain, knee pain, hip pain or pain in the groin area.

3. Limited hip joint activity (especially internal rotation). .

4, accompanied by lower limb pain or chills (fear of cold).

5, limp.

Sign

1, the hip joints are not obvious red, swollen, hot, deformed, with or without gait, with or without muscle atrophy (femoral quadriceps, and gluteus maximus).

2, large rotor button angle (+), tenderness (+) in the central part of the groin, tenderness of the adductor muscle.

3, with or without limb shortening, axial pain in the affected limb (+).

4. Early: Thomas (+), "4" test (+) (same as above) 5. Late: Allis sign (+), single leg independent test (trendelenburg) sign (+), Ober Test (+).

Orthopedic examination

1. Comprehensive inquiry about medical history: Avascular necrosis of the femoral head is usually caused by other diseases or external trauma and some bad habits. Symptoms caused by different causes are different. For a more accurate diagnosis, it is necessary to ask for a medical history. Usually ask about the time, nature, extent, location, etc. of the pain. Have a history of trauma, history of taking hormones, history of drinking, etc., and understand past history, professional history and so on.

2, physical examination: observe the patient's gait, check the range of hip joint movement, the measurement of the length and circumference of the lower limbs, local tenderness of the hip joint, do the "4" test of the lower limbs, Toma's sign, Avery Si Zheng and sniper test.

3, auxiliary examination: patients taking X-ray films can see the femoral skull trabecula, there may be osteoporosis, uneven bone density, cystic changes, collapse, deformation, or narrow joint space. However, the X-ray film is relatively rough, and the early symptoms of femoral head necrosis are not obvious on the film. It is not easy to diagnose. At this time, CT, MRI, etc. can be used to see the rough and localized capsule on the femoral head. Change, etc., are symptoms of femoral head necrosis.

Differential diagnosis

It is differentiated from diseases such as rheumatism, rheumatoid, ankylosing spondylitis, bone and joint tuberculosis, bone hyperplasia, sciatica, and intervertebral disc prolapse.

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