Unilocular bone cyst

Introduction

Introduction to single atrial bone cyst The single-portal bone cyst (solitarybonecyst) is a single cavity with a thin film and a grassy yellow liquid. The bone cyst is often located on the metaphysis of the tibia and femur. The wall of the cyst is often accidentally discovered after trauma or even pathological fracture, or The lesions at the upper end of the femur often cause attention due to abnormal gait. basic knowledge The proportion of illness: 0.003% Susceptible people: no specific people Mode of infection: non-infectious Complications: abnormal gait

Cause

The cause of single atrial bone cyst

(1) Causes of the disease

The true cause is unknown, and it seems to be related to localized ossification of the metaphysis during the vigorous growth of the bone. Some authors suggest that the cancellous or intramedullary hemorrhage is the cause of a single cyst; another theory is cyst. The wall is composed of various primitive mesoderm components, so it is considered that the cyst originates from the tumor tissue with developmental disorders; or the cancellous bone with rapid growth can produce bone cysts. Some authors believe that the bone cyst is caused by mechanical external force damage. The result of intercellular fluid circulation blockade.

(two) pathogenesis

The cause of bone cysts is not clear, and there are various theories.

1. Intramedullary hematoma theory for some reason (including traumatic factors) causes bleeding in the metaphyseal or other parts of the bone tissue, forming a localized hematoma, failed to absorb or ossify in time, and increasing, compressing and eroding the surrounding bone The quality gradually expands, and at the same time, the lymphatic vessels in the bone marrow ooze out to form a bone cyst.

2. Intraosseous venous obstruction The local developmental abnormality of the bone during growth and development causes the local venous return to be blocked, resulting in the accumulation of interstitial fluid. As the tension increases, the bone is absorbed and gradually forms a bone cyst. Cohen performed in 1960. The analysis of the chemical composition of the liquid in the capsule (sugar, sodium, chlorine, non-protein nitrogen, total protein) and protein electrophoresis analysis and serum composition are similar. Enneking and Makley performed intracapsular angiography to find active bone cysts when injecting contrast agents. The nearby venous plexus immediately ingested and spread to the surrounding area. The non-active bone cyst was filled with contrast agent and did not immediately penetrate into the peripheral venous tube. In 1982, Malauer performed intracapsular pressure measurement, and the activity type result was 160mmH2O (12mmHg). ), the water column has pulsation, consistent with the pulse; the latent result is 60 ~ 100mmH2O (5 ~ 7mmHg), lower than the venous pressure, Shindll measured the pressure change of the untreated bone cyst fluid, the venous pressure with the pulse change is equal Or similar, no pressure or pressure is measured for old lesions. In 1986, Maski, Chigira measured the pressure in the capsule and the gas analysis of the liquid. Also we consider that vein obstruction is a major cause of bone cysts.

3. Intraosseous synovial cell misconstruction theory In 1978, Mirra first reported the ultrastructural observation of the wall of the cystic cyst. It was found that there were 3 to 4 layers of cells in the wall of the capsule, and the luminal cells (Luminal cells) had many directional cilia. Like synovial cells and endothelial cells, synovial-like A cells and B cells can be seen on the wall of the capsule. Mirra believes that during embryonic or infancy, for some reason, such as birth injury, synovial cells are embedded in the bone, and There is also a secretory function, the secretion of serum gradually forms a bone cyst, this theory explains why bone cysts occur in children, mostly in the metaphysis, with multiple upper humerus and upper femur, because of their large range of joint activities, synovial There are more attachments at the ankle, but it is not easy to explain the onset of adult disease or other parts such as ribs and calcaneus.

4. The doctrine secondary to other diseases occurs cystic degenerative changes on the basis of the original bone lesions, such as the transformation of benign fibrous tumors, degeneration of lipomas.

5. Others learn that the epiphyseal plate injury, the formation of cysts in the cartilage osteogenesis disorder; local bone malformation development and metabolic disorders, osteoclasts promote the absorption of trabecular bone to form bone cysts; bone local nutrition disorders to form cystic changes , low-infection inflammatory theory and so on.

During the operation, the periosteum of the lesion was not changed or slightly thickened. The lesions were mostly single-chamber, the wall was thin, and the wall of the capsule was lined with a thin layer of fibrous membrane. The capsule was transparent or translucent yellow liquid or bloody liquid. The epiphysis protrudes into the cyst, but does not form multiple chambers. The bone of the lower wall of the microscope is a normal bone structure. The wall of the fibrosis is loose connective tissue or thick and vascular connective tissue, mainly fibroblasts and multinuclei. Giant cells (Fig. 1), which are small, can be piled up or dispersed in the inner wall of the capsule, and combined with pathological fractures, new bone formation under the bone cavity with fibrosis of the cyst wall.

The wall of the capsule, such as the thickness of the eggshell, causes the appearance of the capsule to be blue due to the liquid in the capsule. The wall of the capsule is cut and the liquid is discharged from the grass. If a pathological fracture has recently occurred, the liquid may be bloody, except for repeated fractures. There is a fibrous space in the cyst cavity, which is generally a single room. There is an epiphysis in the wall of the capsule. The cavity is lined with a layer of connective tissue film of about 1 mm, and the color is reddish brown.

Pathologically non-specific, the fibrous membrane is connective tissue, containing giant cells, phagocytic cells, hemosiderin-containing brown particles and yellow tumor cells, and reactive new bone formed after fracture of the cyst wall.

Prevention

Single atrial bone cyst prevention

Refer to the general tumor prevention methods, understand the risk factors of tumors, and formulate corresponding prevention and treatment strategies to reduce the risk of tumors. There are two basic clues to prevent tumors. Even if tumors have begun to form in the body, they can help the body to improve resistance. These strategies are as follows:

1. Avoid harmful substances (promoting factors) that can help us avoid or minimize exposure to harmful substances.

Some related factors of tumorigenesis are prevented before the onset, and many cancers can be prevented before they are formed. A report in the United States in 1988 compared the international malignant tumors in detail and proposed many external factors of known malignant tumors. In principle, it can be prevented, that is, about 80% of malignant tumors can be prevented by simple lifestyle changes, and traced back. In 1969, Dr. Higginson's research concluded that 90% of malignant tumors are caused by environmental factors," "Environmental factors", "lifestyle" refers to the air we breathe, the water we drink, the food we choose to make, the habits of activities, and social relationships.

2. Improve the body's immunity against tumors can help improve and strengthen the body's immune system and cancer.

The focus of our current cancer prevention efforts should first focus on and improve those factors that are closely related to our lives, such as quitting smoking, eating properly, exercising regularly, and losing weight. Anyone who follows these simple and reasonable lifestyles can Reduce the chance of cancer.

Human epidemiology and animal studies have shown that vitamin A plays an important role in reducing the risk of cancer. Vitamin A supports normal mucosa and vision. It directly or indirectly participates in most of the body's tissue functions. Vitamin A is present in animal tissues. In the liver, whole eggs and whole milk, the plant is in the form of -carotene and carotenoids, which can be converted into vitamin A in the human body. Excessive intake of vitamin A can cause adverse reactions in the body and -carrot This is not the case with carotenoids, and the low vitamin A content in the blood increases the risk of malignant tumors. Studies have shown that those with low levels of vitamin A intake in the blood increase the likelihood of lung cancer, while those with low blood levels in smokers Levels of vitamin A ingestors have the potential to double lung cancer. Vitamin A and its mixture can help remove free radicals in the body (free radicals can cause damage to genetic material), and secondly stimulate the immune system and help differentiate cells in the body. Ordered tissue (while the tumor is characterized by disorder), some theories suggest that vitamin A can help early carcinogens Invasion mutated cells become reversed the occurrence of the normal growth of cells.

In addition, some studies suggest that supplementation with -carotene alone does not reduce the risk of cancer, but rather increases the incidence of lung cancer. However, when -carotene binds to vitamin C, E and other antitoxin substances, its protective effect. It is shown, because it can increase free radicals in the body when it is consumed by itself. In addition, there are interactions between different vitamins. Both human and mouse studies have shown that the use of -carotene can reduce 40% of vitamins in the body. At E-level, a safer strategy is to eat different foods to maintain a balanced vitamin to protect against cancer, as some protective factors have not been discovered so far.

Vitamin C, E is another anti-tumor substance that prevents the harm of carcinogens such as nitrosamines in food. Vitamin C protects sperm from genetic damage and reduces the risk of leukemia, kidney cancer and brain tumors in their offspring. Vitamin E can reduce the risk of skin cancer. Vitamin E has the same anti-tumor effect as vitamin C. It is a scavenger that protects against toxins and scavenges free radicals. The combination of vitamins A, C and E protects the body against toxins. Better than applying it alone.

At present, research on phytochemistry has attracted widespread attention. Phytochemistry is a chemical found in plants, including vitamins and other substances found in plants. Thousands of plant chemicals have been found, many of which have anticancer properties. The protective mechanism of these chemicals not only reduces the activity of carcinogens but also enhances the body's immunity against carcinogens. Most plants provide antioxidant activity that exceeds the protective effects of vitamins A, C, and E, such as a cup of cabbage. Contains 50mg of vitamin C and 13U of vitamin E, but its antioxidant activity is equivalent to the antioxidant activity of 800mg of vitamin C and 1100u of vitamin E. It can be inferred that the antioxidant effect in fruits and vegetables is far better than what we know. The effect of vitamins is strong, and no doubt natural plant products will help prevent cancer in the future.

Complication

Single atrial bone cyst complications Complications gait abnormalities

Can cause pathological fractures, abnormal gait, etc.

Symptom

Symptoms of single-atrial bone cyst Common symptoms Osteoostosis, developmental deformity, tendon cyst, persistent pain at the humerus, abnormal gait, bone cyst

Bone cysts are often located on the metaphysis of the tibia and femur. Older patients are often located in the humerus, calcaneus and metacarpal. About 2/3 of the cases have no symptoms, and 1/3 of the cases have local pain, soreness, tenderness and tenderness. In a small number of patients, the local mass and bone thickening, the vast majority of patients in the occurrence or repeated pathological fractures to see a doctor, the wall more than due to trauma or even pathological fractures were found accidentally, except for the injury is generally no pain, the upper femoral lesions often cause State exceptions cause attention.

The most common site of the long-tubular humeral end is the long bone, the proximal end of the tibia and femur is a good site, 55% at the proximal end of the humerus, 25% at the proximal femur, other parts of the distal femur, proximal humerus, distal radius, with Bone, ribs, a few found in the metacarpal, clavicle, humerus, pubic and ischial, humerus.

The bone cyst of the calcaneus is mostly located in the anterior middle part of the calcaneus, and the lower middle part is more than the upper part, which is equivalent to the anterior and posterior aspect of the posterior articular surface, and the lateral part of the heel, accounting for 1/2 to 2/3 of the width.

Bone cysts in the humerus often have a large expansive bulge, and there may be a small cavity in the wall of the sac, which needs to be differentiated from an aneurysmal bone cyst.

Bone cysts often come from the metaphyseal end near the sputum growth plate. Due to the normal new bone formation of the tarsal plate, the bone cyst gradually shifts toward the diaphysis as the age increases. This movement depends on the growth ability of the normal bone, near the humerus. The end moves more than the distal end of the humerus and is smaller than the distal end of the femur at the proximal end of the femur. Some people disagree with this statement.

The patient has no obvious symptoms. He feels pain after exertion. The lesions can be paralyzed and superficially elevated in the superficial area. The locality may or may not be tender. Therefore, it is often overlooked. About 2/3 of the patients have pathological fractures. The fracture can be healed normally after treatment. The limb often undergoes varus and shortened deformity, which occurs mostly after pathological fracture. It is also caused by the reduction of local bone strength and the weight of the lesion. It also causes developmental malformation due to the destruction of osteophyte cartilage. .

Clinically, the bone cysts are divided into two types. Jaffe believes that the bone cyst is mainly in the vicinity of the tarsal plate. The active cyst is called active type. The growth ability away from the tarsal plate is relatively small, called latent type. Makley and Joyce think that About 4 years old, the lesion is close to the growth plate, and gradually moving to the metaphysis end is called active bone cyst, aged 8 to 13 years old, the middle of the diseased metaphysis or the backbone is called quiescent bone cyst.

Examine

Examination of single atrial bone cyst

(1) Causes of the disease

The true cause is unknown, and it seems to be related to localized ossification of the metaphysis during the vigorous growth of the bone. Some authors suggest that the cancellous or intramedullary hemorrhage is the cause of a single cyst; another theory is cyst. The wall is composed of various primitive mesoderm components, so it is considered that the cyst originates from the tumor tissue with developmental disorders; or the cancellous bone with rapid growth can produce bone cysts. Some authors believe that the bone cyst is caused by mechanical external force damage. The result of intercellular fluid circulation blockade.

(two) pathogenesis

The cause of bone cysts is not clear, and there are various theories.

1. Intramedullary hematoma theory for some reason (including traumatic factors) causes bleeding in the metaphyseal or other parts of the bone tissue, forming a localized hematoma, failed to absorb or ossify in time, and increasing, compressing and eroding the surrounding bone The quality gradually expands, and at the same time, the lymphatic vessels in the bone marrow ooze out to form a bone cyst.

2. Intraosseous venous obstruction The local developmental abnormality of the bone during growth and development causes the local venous return to be blocked, resulting in the accumulation of interstitial fluid. As the tension increases, the bone is absorbed and gradually forms a bone cyst. Cohen performed in 1960. The analysis of the chemical composition of the liquid in the capsule (sugar, sodium, chlorine, non-protein nitrogen, total protein) and protein electrophoresis analysis and serum composition are similar. Enneking and Makley performed intracapsular angiography to find active bone cysts when injecting contrast agents. The nearby venous plexus immediately ingested and spread to the surrounding area. The non-active bone cyst was filled with contrast agent and did not immediately penetrate into the peripheral venous tube. In 1982, Malauer performed intracapsular pressure measurement, and the activity type result was 160mmH2O (12mmHg). ), the water column has pulsation, consistent with the pulse; the latent result is 60 ~ 100mmH2O (5 ~ 7mmHg), lower than the venous pressure, Shindll measured the pressure change of the untreated bone cyst fluid, the venous pressure with the pulse change is equal Or similar, no pressure or pressure is measured for old lesions. In 1986, Maski, Chigira measured the pressure in the capsule and the gas analysis of the liquid. Also we consider that vein obstruction is a major cause of bone cysts.

3. Intraosseous synovial cell misconstruction theory In 1978, Mirra first reported the ultrastructural observation of the wall of the cystic cyst. It was found that there were 3 to 4 layers of cells in the wall of the capsule, and the luminal cells (Luminal cells) had many directional cilia. Like synovial cells and endothelial cells, synovial-like A cells and B cells can be seen on the wall of the capsule. Mirra believes that during embryonic or infancy, for some reason, such as birth injury, synovial cells are embedded in the bone, and There is also a secretory function, the secretion of serum gradually forms a bone cyst, this theory explains why bone cysts occur in children, mostly in the metaphysis, with multiple upper humerus and upper femur, because of their large range of joint activities, synovial There are more attachments at the ankle, but it is not easy to explain the onset of adult disease or other parts such as ribs and calcaneus.

4. The doctrine secondary to other diseases occurs cystic degenerative changes on the basis of the original bone lesions, such as the transformation of benign fibrous tumors, degeneration of lipomas.

5. Others learn that the epiphyseal plate injury, the formation of cysts in the cartilage osteogenesis disorder; local bone malformation development and metabolic disorders, osteoclasts promote the absorption of trabecular bone to form bone cysts; bone local nutrition disorders to form cystic changes , low-infection inflammatory theory and so on.

During the operation, the periosteum of the lesion was not changed or slightly thickened. The lesions were mostly single-chamber, the wall was thin, and the wall of the capsule was lined with a thin layer of fibrous membrane. The capsule was transparent or translucent yellow liquid or bloody liquid. The epiphysis protrudes into the cyst, but does not form multiple chambers. The bone of the lower wall of the microscope is a normal bone structure. The wall of the fibrosis is loose connective tissue or thick and vascular connective tissue, mainly fibroblasts and multinuclei. Giant cells (Fig. 1), which are small, can be piled up or dispersed in the inner wall of the capsule, and combined with pathological fractures, new bone formation under the bone cavity with fibrosis of the cyst wall.

The wall of the capsule, such as the thickness of the eggshell, causes the appearance of the capsule to be blue due to the liquid in the capsule. The wall of the capsule is cut and the liquid is discharged from the grass. If a pathological fracture has recently occurred, the liquid may be bloody, except for repeated fractures. There is a fibrous space in the cyst cavity, which is generally a single room. There is an epiphysis in the wall of the capsule. The cavity is lined with a layer of connective tissue film of about 1 mm, and the color is reddish brown.

Pathologically non-specific, the fibrous membrane is connective tissue, containing giant cells, phagocytic cells, hemosiderin-containing brown particles and yellow tumor cells, and reactive new bone formed after fracture of the cyst wall.

Diagnosis

Diagnosis and diagnosis of single atrial bone cyst

Diagnostic criteria

1. Active type (active period) The cyst is close to the epiphysis line, the distance is less than 0.5cm, and the age is below 10 years old.

Active bone cysts indicate that the lesions are constantly developing. During the expansion process, any method of treatment is easy to relapse. The recurrence rate of the lesions after surgery is very high, about 50%. Makley points out that under 10 years old, X-ray shows active bone cysts. The recurrence rate of patients treated with surgery was as high as 88%. Oppenhem and Galleo pointed out that the complications of this operation were mainly growth disorders, the incidence rate was 17%, and the level of prostaglandin E2 in the cystic fluid was significantly increased by Shiudell et al. This indicates that the fluid in the capsule plays a role in the stimulation of osteoclast activating factor in the presence of the cyst.

2. Latent type (quiescent period) The cyst is farther away from the sacral line, the distance is greater than 0.5cm, and the age is over 10 years old.

Latent bone cysts, lesions rarely progress, the lesions can be far away from the sacral line in the middle of the metaphysis or the backbone, cysts are mostly single-room, sometimes multi-room, the recurrence rate after treatment is lower, Neer contrast The recurrence rate of 67 active types and 28 latent bone cysts at the upper end of the tibia was not significant.

Bone cysts involving the epiphysis are rare. The lesion spans between the epiphysis and the metaphysis. The swelling is light, the development is slow, and the age of onset is large. It is more common in the proximal humerus and proximal femur. After treatment, the effect on joint function is not significant. Bone cysts that pass through the growth plate can cause growth disorders, resulting in various deformities such as varus, angulation, and short limb deformity.

The diagnosis of this disease mainly depends on X-ray examination and pathological biopsy. The diagnosis of typical bone cyst is not difficult. The pathological fracture suddenly occurs in childhood, and there is a "deciduous sign" to confirm the diagnosis. X-ray examination, a long bone (upper end of the humerus, femur) The upper end is located on the lateral side of the epiphysis line, at the center of the metaphysis, with a fusiform expanded transparent shadow, the edge of which is completely surrounded by a thinned cortical bone, the boundary is clear, and there may be irregular interosseous space in the cavity. Then you can diagnose.

Differential diagnosis

1. Aneurysmal bone cysts Single bone cysts are central expansion, tumorous bone cysts are eccentrically dilated. After fractures of bone cysts, bloody fluids or blood clots in the capsules, each obscuring the gross pathology of the two. Hyperparathyroidism is more common in adulthood, and elevated blood calcium can be identified.

2. Uni-bone fibrous heterogeneous proliferation of single-bone fibrous heterogeneous cells and single-bone cysts are similar to images. Fiber-like bone lesions with fibrous abnormalities show fine trabeculae in the ground-glass image, especially after amplification. The lesions that proliferate in the fiber are mostly eccentrically dilated.

3. Giant cell tumors Single bone cysts should not be confused with giant cell tumors. Giant cell tumors occur mostly in adults, almost all of them invade the sacs. Their tumor cell lines are typical of spindle cells and oval stromal cells. There are many nuclear giant cells scattered. Although bone cysts can see giant cells, they do not see interstitial cells.

4. The clinical manifestations of eosinophilic granuloma are painful. The lesion is located near the middle of the backbone, and the size is not as large as the bone cyst. The new bone is beyond the lesion area. The histological examination shows eosinophils.

5. Although the endogenous chondroma is cystic, it occurs in the backbone of short tubular bone. The chondroma often has a bit of calcified foci. In some cases, X-ray photographs cannot be taken alone and need to be examined by histological examination.

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