Bone cysts are benign lesions of bone, also known as isolated bone cysts, simplebonecyst, with a fibrous envelope wall and yellow or brown liquid inside the cyst. Bone cysts are usually found in the epiphysis of long bones and the medullary cavity of the bone stem, but rarely occur in the vertebral body, and are more common in adolescents in their 20s, and more in males than females.
Symptoms and signs I. Clinical manifestations.
1, it occurs in 4-20 years old, mostly in children aged 5-15 years old, it occurs in femoral neck, upper femur and upper humerus, with age, the cyst gradually moves towards the diaphysis.
2. Generally, there are no obvious symptoms, and most of them are seen due to pathological fracture, pain, swelling and dysfunction, and the disease is only discovered by X-ray radiography.
3.X-ray shows oval osteolytic destruction at the D end of the long bone stem or the bone stem, with clear borders and a thin sclerotic zone around it, and the bone cortex may have mild expansion and thinning.
Second, the diagnosis is based on.
1. Most commonly seen in children and adolescents, mostly in the long bone epiphysis.
Pathological fracture may be the earliest symptom and sign, or the lesion may be found by X-ray.
3.X-ray shows an oval-shaped transparent shadow with uniform density in the long bone epiphysis, and the lesion is limited with a clear boundary between normal bone and swollen and thin bone cortex.
4.Pathological examination can confirm the diagnosis.
Treatment I. Principles of treatment.
1.Bone cyst is mainly treated by surgery. Surgical scraping and bone grafting are required to thoroughly scrape away the fibrous envelope during surgery to prevent recurrence.
2, combined with pathological fracture, sometimes the bone cyst can heal by itself. If the cyst still remains after the fracture heals, surgery should be performed.
3.For pediatric patients, methylprednisolone acetate can be injected into the cavity of the bone cyst. The injection amount is 40-200 mg, depending on the size of the cyst and the age of the child.
Second, the principles of medication.
1.Bone cyst patients are mainly treated by surgical scraping and bone grafting.
2. In the past decade or so, intracavitary injections of methylprednisolone acetate have been used at home and abroad for several times, and the amount of medication depends on the size of the cyst and the age of the child, generally 40-200 mg is used once every 2 months.
Third, the efficacy evaluation.
1, cure: cystic cavity disappears or fracture healing, bone repair changes. Wound healing.
2. Improvement: combined with pathological fracture, fracture healing, bone cyst mostly healed or cyst cavity reduced.
Diet
Mostly light food, pay attention to the regular diet.
Prevention
The cause of this disease is not yet known, and there are no effective preventive measures, so early detection, early diagnosis and early treatment are the key to prevention and treatment of this disease.
Some scholars believe that bone cyst is due to obstruction of blood vessel endings in bone and blood stagnation; some believe that the disease is a tumor, degenerative changes of inflammatory tissue, its growth, the result of metabolic obstruction or related to abnormal bone development; some believe that it may be due to traumatic bleeding to form a limited capsule, and then local resorption and ossification.
Disease diagnosis This disease is similar to the abnormal proliferation of bone fibers imaging manifestations, the differentiation is more difficult, there are several main points of differentiation as follows.
1, clinical manifestations.
The clinical symptoms of osteochondrodysplasia are limited elevation or swelling, pain, deformity, and slow development of the disease. Patients with bone cysts generally have no obvious symptoms, or only vague pain, intermittent, or soreness after exercise and exertion.
2, abnormal bone fiber proliferation disease and bone cyst lesion morphology and internal structure.
Most of the bone cysts are ovoid with uniform density inside the cyst; while the morphology and internal structure of bone fiber abnormal proliferation disease are diverse and can be divided into worm-eaten type, cystic type, ground glass type, filiform type and sclerotic type.
3. Displacement of bone fragments in case of pathological fracture.
When a bone cyst is combined with pathological fracture, bone fragments are displaced into the cystic cavity; while when pathological fracture occurs in osteochondrodysplasia, bone fragments are not obviously displaced, less bone scabs are formed, and bone nonunion is easily formed.
4. Occurrence site.
When bone cysts occur in the epiphysis, they do not exceed the epiphyseal plate; whereas osteochondrodysplasia involving the epiphysis often crosses the epiphyseal plate, and its adjacent epiphysis have the imaging performance of osteochondrodysplasia.
In addition, this disease should be differentiated from giant cell tumor of bone, eosinophilic granuloma and aneurysmal bone cyst.
Examination methods bone cyst is a kind of tumor-like bone disease of unknown cause, which has no conscious symptoms in the clinic, and is only detected by X-ray examination after the occurrence of pathological fracture, the auxiliary examination methods are as follows.
1.Pathological examination: In pathology, the size of the cyst is mostly between 3~10
The cyst cavity contains brownish-yellow transparent liquid or bloody liquid, the composition of which is the same as that of serum, and the inner wall is covered with a thin and smooth fibrous connective tissue membrane.
2.X-ray examination: X-ray plain film mainly shows swollen bone destruction, located in the center of the medullary cavity, surrounded by a thin sclerotic ring.
3.CT examination: CT shows round or oval low-density foci located in the center of the bone marrow cavity, watery density, cystic expansion, and occasionally slightly higher density within the foci, suggesting the possibility of bleeding.
4.MRI examination: MRI performance is typical, the boundary of the lesion is usually bright and neat, the signal intensity depends entirely on the protein content of the fluid, generally the cyst fluid is very uniform low signal on T1WI and very uniform high signal on T2WI, the lower the protein content, the signal intensity is closer to water, high protein content is slightly higher than water on T1WI and slightly lower than water on T2WI.
Complications
The most common complication of bone cysts is pathological fracture. When a bone cyst is combined with a pathological fracture, the fracture fragment is displaced into the cavity due to the outflow of fluid from the cyst, a sign called “fragment trapping sign”, which was introduced by Reynolds.