[Poliostotic fibrous dysplasia with affectation of cervical rachis].

The fibrous dysplasia is a benign although progressive dysfunction, in which a gene mutation originates the production of fibrous disorganized bony matrix. The bony tissue is replaced by bony tissue in expansion (amorph conjuntival tissue) that produces bony deformities in some patients, pain, pathological fractures or deambulation disorders. The diagnosis is important since ocasionally the first symptom is the fracture. We show up the case of a 21 year-old patient with pain clinic in high cervical region. The complementary tests (radiology, bone scintigrraphy and MRI) and anatomo-pathology confirmed the diagnosis of polyostotic fibrous dysplasia with cranial (occipital, esfenoides and right frontal and temporal bone), iliac, femoral, tibial and cervical (apophysis of C2) affectation. Our attitude was of carrying out a narrow observation by means of periodical strict controls, advising to avoid hard activities or contact sports. To the five years the patient is free of symptomatology. Radiologically the injuries have been stabilized. The fibrous dysplasia can affect to a single bone (monostotic) or to several (polyostotic). In occasions it is associated to endocrine dysfunctions and skin pigmentations in McCune-Albright's syndrome. We confront a pathology that specifies an anatomo-pathologic diagnosis to be confirmed, an extension diagnosis to detect asymptomatic focuses and whose treatment is symptomatic in most of the cases only using surgery in frank deformities or when the fracture risk is considerable, although the recurrence is frequent. The malignization is exceptional but possible that's why continuous observation is needed. The radiation therapy is radically contraindicated.