How to treat bone cysts and what causes them

For children around 10 years old, if they experience unexplained bone pain, swelling and other problems, it is most likely caused by bone cysts. Bone cyst is an invisible disease that is difficult to detect and is currently classified as a benign lesion. Bone cysts can be caused by congenital or acquired factors. Once diagnosed, it is important to cooperate with the doctor and actively receive treatment.

1. Causes of bone cysts

What are the causes of bone cysts? What causes bone cysts? The following is an introduction to the causes of bone cysts:

The exact cause of bone cysts is unknown, and there are many theories. Mirra speculates that it may be that during the embryonic period, a small number of synovial cells with secretory functions sink into the bones, resulting in the accumulation of synovial fluid and the formation of bone cysts.

The pathogenesis of simple bone cysts is still unclear, but it is generally believed to be related to post-traumatic response. The most popular theory of the occurrence of this disease is that local venous reflux obstruction leads to increased pressure, causing local reactive bone resorption. Experimental data show that prostaglandins and interleukin IB, which are rich in the cystic fluid of simple bone cysts, can independently cause bone resorption. Most bone cysts have no clinical symptoms and are often not discovered until a pathological fracture occurs.

2. Examination of bone cysts

Testing

The diagnosis of bone cyst can usually be confirmed based on clinical manifestations and X-rays. Blood eosinophil examination is mainly related to the differentiation from eosinophilic granuloma. For inpatients undergoing surgery, in addition to basic examinations, optional examination items may be selected as appropriate, and special examinations are generally not required.

Imaging findings

X-ray shows that the lesion is a clearly defined radiolucent area with a thin layer of bone sclerosis on the outside. Due to the expansive growth of the cyst, the bone cortex becomes irregularly thinned. X-ray films often show a pseudolobulated appearance. The cyst often extends downward from the epiphysis of the humerus or femur to the shaft. Although it extends upward close to the epiphysis, the latter may be involved. Pathological fractures are very common. The cyst may have the illusion of a bone ridge. Pathological examination shows that the lesion is a single-chamber cyst cavity filled with clear fluid and lined with a thin layer of fibrous tissue. After fracture, the cavity contains bloody fluid and bone callus appears.

X-ray

X-rays showed an oval transparent shadow with uniform density at the epiphysis of the long bones. The lesion was localized with a clear boundary between the lesion and the normal bone, and the bone cortex was expanded and thinned. It manifests as mild expansive growth, local thinning of the bone cortex, smooth edges, and no periosteal hyperplasia. When combined with pathological fractures, bone fragments shift into the capsule, which is called the "fragment collapse sign" and helps with identification.

3. Treatment principles of bone cysts

1. Bone cysts are mainly treated with surgery. During the surgery, the fibrous capsule must be thoroughly scraped off to prevent recurrence.

2. In patients with pathological fractures, bone cysts can sometimes heal on their own. If a cyst remains after the fracture heals, surgery should be performed.

3. For pediatric patients, methylprednisolone acetate can be tried by injecting it into the bone cyst cavity. The injection volume is 40-200 mg, depending on the size of the cyst and the age of the child.

4. In the past ten years, both at home and abroad, methylprednisolone acetate has been injected into the cyst cavity multiple times. The dosage depends on the size of the cyst cavity and the age of the child. Generally, 40-200 mg is used, once every two months.