Young athletes can reduce their risk of traumatic bone cyst by wearing protective mouth wear or protective headgear. History
Aneurysmal bone cysts are benign neoformations which can affect any bone. More than half occur in the metaphysis of long bones (especially femur and tibia) and between 12 and 30% in the spine. They were described in 1893 by Van Arsdale, who called these lesions "homerus ossifying haematoma". In 1940 Ewing used the term "aneurismal" to describe these lesions. Jaffé and Lichtenstein first coined the term "aneurismal cyst" in 1942 In 1950 they modified this term to "aneurismal bone cyst". They may be associated with bone tumors. The simple bone cyst is a common, benign, fluid-containing lesion, most commonly found in the metaphysis of long bones, typically the proximal humerus or femur. Pathologic fractures are common, often with minor trauma. These cysts typically resolve after skeletal maturity and are not typically associated with bone tumors. The cause  is unknown. These were first recognised as a distinct entity in 1910. Jaffe and Lichtenstein provided a detailed discussion of simple bone cysts in 1942.The traumatic bone cyst, also referred to as a simple bone cyst or hemorrhagic cyst, is a pseudocyst that most commonly affects the mandible of young individuals. It is a benign empty or fluid-containing cavity within the mandible body that does not have evidence of a true epithelial lining. This type of bone cyst is a condition found in the long bones and jaws.
Other genes that are commonly thought to be associated with lupus are those in the human leukocyte antigen (HLA) family. There have been several cases wherein a single gene influence appears to be present, but this is rare. When a single gene deficiency does cause lupus, it is usually attributed to the complement protein genes C1, C2, or C4. The influence of sex chromosomes and environmental factors are also noteworthy. Usually, these factors contribute to lupus by influencing the immune system. Several studies also indicate a potential association of lupus with mutations in DNA repair genes. Age difference
Lupus can develop in people at any age, but it does most commonly at ages 15 to 44, with varying results. Typically, the manifestation of the disease tends to be more acute in those of younger age. Women are more likely to get it than men. Patients with juvenile-onset lupus are more vulnerable to mucocutaneous manifestations of the disease (alopecia, skin rash, and ulceration of the mucus membranes) than any other age group, and they are also more susceptible to evaluation of pulmonary artery pressure. However, patients with late-onset lupus have a much higher mortality rate. Nearly 50% of those with late-onset lupus die of their condition. Women who are of childbearing age are also particularly at risk. Differences in ethnicity
Substantial data have been found to indicate that certain ethnic populations could be more at risk for lupus erythematosus and to have a better or worse prognosis.