Fibroma nonossificans is a benign, non-neoplastic lesion that most often occurs in young people between 5 and 15 years of age. What are the causes and symptoms of non-ossifying fibroma? How is his treatment going?
Non-melting fibroma( fibroma nonossificans ) is one of the most common benign non-cancerous bone lesions. The reasons for its formation are unknown, but it is known that it is a kind of developmental defect in which the areas of normal ossification are occupied by connective tissue. It occurs in children and adolescents, mainly between 5 and 15 years of age, more often in boys than in girls. Typically, it is located around the epiphyses of long bones - usually the distal metaphysis of the femur and the proximal metaphysis of the tibia. As the skeleton grows, it can move towards the epiphyses of the bones. Its diameter rarely exceeds a few centimeters. Rarely, non-ossifying fibromas appear symmetrically in two bones or are multiple and coexist with pigmented lesions of the skin (Jaffe Campanacci syndrome).
Non-ossifying fibroma: symptoms
Small-sized non-ossifying fibromas usually do not cause any discomfort, and most of them are detected accidentally when radiological examinations are performed for other indications.
In the case of extensive fibromas, they cause pain due to the presence of microfractures and swelling of the affected limb. Moreover, they can cause pathological fractures.
Non-ossifying fibroma: diagnosis
Macroscopic changes appear gray or yellow-brown. On the other hand, microscopic examination shows that the lesions are composed of cytologically benign fibroblasts forming a spinous system and multinucleated giant cells. Foci of haemorrhagic lesions, hepatocellular tissue and hemosiderin deposits are often present.
The diagnosis is based on an X-ray examination, which shows a fibrous bone defect, well delimited from the environment by a sclerotic border, usually of a round shape, located eccentrically. It should be borne in mind that a similar X-ray image can be seen in low-grade fibrosarcomas.
Non-ossifying fibroma:treatment
Due to the fact that most non-ossifying fibroids spontaneously retreat during or shortly after adolescence, the presumptive procedure is adopted. Small changes in children require a control X-ray image every six months. Surgical treatment may be appropriate for large fibroids.
Asymptomatic lesions covering less than 50% of the bone cross-section are monitored as the lesion sometimes heals itself through bone remodeling processes. If the lesion grows larger, it becomes necessary to curettage and fill the resulting defect with bone grafts.
In the case of large non-ossifying fibromas, covering more than 50% of the bone cross-section, there is an increased risk of pathological fracture. In such cases, surgical treatment should be considered, including curettage and filling the defect with bone grafts. Additionally, it may be necessary to use internal fixation in places particularly at risk of fracture, e.g. in the proximal end of the femur.
Patients with pathological fractures should, if possible, be treated non-surgically. There is evidence that healing of the fracture increases the chance of spontaneous healing of non-osteogenic fibroma. However, it should be remembered that a patient with a pathological fracture must be monitored until the callus remodels sufficiently and the nature of the lesion being the cause of the fracture is finally determined. If, despite the fracture healing, the lesion does not heal itself, surgical treatment is recommended - curettage and filling the defect with bone grafts.