Ankylosing Spondylitis may occur by itself, or be associated with other disorders such as psoriasis or inflammatory bowel disease. Patients with ankylosing spondylitis may develop several problems regarding their spines. The first is that they are prone to spinal fractures with even minimal trauma. Even a simple fall may cause a serious spinal fracture in someone with ankylosing spondylitis. The second problem is that ankylosing spondylitis patients are prone to develop progressive kyphotic deformity.
Kyphosis is a forward bending of the spine.
In either case, because of the rigidity of the ankylosing spondylitis spine, the kyphotic position makes it difficult for the patient to stand and look forward. As the kyphosis progresses the patient becomes more and more stooped and the visual horizon gets lower and lower. Simple daily activities can become progressively more difficult to perform. In addition, the abnormal posture may contribute to complaints of back pain. This is a very gradual process in most cases, occurring over many years.