Among individuals with skeletal fluorosis, the fluoride-induced changes to the spine, and the accompanying symptoms, can bear a close resemblance to DISH (Forestier’s Disease). Some authors report that skeletal fluorosis can so closely resemble DISH that the only way to distinguish the two would be to conduct an invasive bone biopsy. No studies have ever been conducted to determine what role, if any, fluoride plays in the development of DISH.

DISH is a degenerative form of arthritis and is characterized by excessive calcification along the sides of the spine. It frequently involves inflammation and calcification of the tendons at their attachment points to bone, which can lead to bone spurs. Heel spurs are thus common among people with DISH. Due to the excessive calcification, DISH can cause joint stiffness and pain, particularly in the back. Neurological manifestations can also result if the bone calcifications in the spine places pressure on the spinal cord.

DISH usually develops in persons between the ages of 50 and 75. In the U.S., the incidence of DISH in men over the age of 50 is estimated to be as high as 19%, and as high as 28% among men older than 80. The incidence in women is much lower, with 4% of women over 50 estimated to have the disease.

Fluoride & DISH:

“Bone marrow biopsy demonstrated severe cortical and trabecular sclerosis with preserved lamellar structure and prominent osteoblastic activity consistent with skeletal fluorosis. . . . Anterior longitudinal ligament (ALL) and ligamentum flavum (LF) hyperostosis like osteophytes, as well as diffuse-idiopathic-skeletal-hyperostosis, were seen on computed tomography.”
SOURCE: Kalia LV, et al. (2010). Thoracic myelopathy from coincident fluorosis and epidural lipomatosis. Can. J. Neurol. Sci. 37:276-78.

“Distinguishing between fluorosis and DISH may be difficult in fragmentary and less severe cases.”
SOURCE: Littleton J. (1999). Paleopathology of skeletal fluorosis. American Journal of Physical Anthropology 109: 465-483.

“Our study shows that hyperostosis of the spine and peripheral skeletal parts occurs more frequently among fluoride-exposed aluminum smelter workers. It is similar to diffuse idiopathic skeletal hyperostosis. Separation of the fluoride-caused form from that etiologically unexplained idiopathic is only possible through bone biopsy.”
SOURCE: Runge H, Franke J. (1989). Radiological modifications of the skeletal system among aluminum smelter workers: A 15 year retrospective study. Fluoride 22: 157-164.

“Hyperostosis as seen in fluorosis cannot be differentiated from Forestier’s syndrome which may also have extraspinal manifestations.”
SOURCE: Boillat MA, et al. (1980). Radiological criteria of industrial fluorosis. Skeletal Radiology 5: 161-165.

“In the aluminum workers, the most frequent changes in the spine were exostoses and ossification of the ligaments. These changes did not differ in appearance from those seen in spondylarthritis or vertebral ankylosing hyperostosis.”
SOURCE: Czerwinski E, Lankosz W. (1978). Skeletal changes in industrial and endemic fluorosis. Fluoride 11:29-32.