2. Ankylosing Spondylitis
Ankylosing spondylitis is a type of inflammatory arthritis that primarily affects the joints in the spine, causing pain and stiffness in areas such as the lower back, buttocks and hips. According to the Arthritis Foundation, these symptoms tend to develop “slowly over several weeks or months.”
Arthritis Research UK adds that ankylosing spondylitis can affect other areas of the body as well, causing chest pain, inflammation of the eyes or bowels, as well as fatigue. Although the condition can affect anyone, the source says it most commonly affects men in their late teens or 20s, particularly if they have a gene called HLA-B27.