M48: Other spondylopathies

M48.1: Ankylosing hyperostosis [Forestier]

Ankylosing hyperostosis, also known as Forestier's disease, is a condition affecting the skeleton system. It occurs when there is an abnormal growth of bone in the spine, resulting in stiffening and in some cases, deformity. This typically impacts the mid and lower parts of the spine, although it can occur anywhere. The symptoms are often confused with osteoarthritis, including chronic back and neck pain along with stiffness. As the condition advances, some people may experience difficulty swallowing or breathing due to the excess bone growth in the neck region. While this condition is most commonly seen in older men, it can affect anyone. Its exact cause is unknown, though it's generally believed to be related to factors like aging and genetic predisposition.