Ankylosing spondylitis (AS) is a chronic, inflammatory rheumatic disease that mainly presenting with chronic back pain. In general, chronic low back pain is currently defined as a mixed pain including nociceptive and neuropathic properties. Nociceptive pain in several rheumatic diseases displays neuropathic characteristics over time. Patients with AS are suffered from spinal, entheseal pain or pain originated from peripheral and root joints. Although being scarce, there are trials investigating and reporting neuropathic component of spinal pain in axial spondyloarthritis/ankylosing spondylitis patients. However these trials either are not controlled or did not specify painful region of interest. In a few controlled trials control subjects were not defined clearly.~Sleep problems are reported to be prevalent among patients with chronic pain conditions such as inflammatory rheumatic diseases and fibromyalgia. In patients with ankylosing spondylitis sleep disturbance is a well defined issue. The fact that sleep problem is a common problem in AS, raises the need to explore it's associates. In the trials measuring spinal neuropathic pain, sleep disturbances and it's association with neuropathic pain were not assessed.~So, investigators have aimed to investigate prevalence of neuropathic spinal pain in AS patients and it's impact on sleep quality. For this purpose a case-control study design was planned. Age- and sex-matched control subjects will be chosen among individuals submitted to out-patient clinic with nociceptive/mechanical pain complaint lasting more than three months. Participants in control group will be subjected to same exclusion criteria too.~This design will allow the investigators to determine whether spinal pain in AS patients displays neuropathic character more frequently than any chronic nociceptive pain does.
The aim of this study is to investigate prevalence of neuropathic spinal pain in AS patients and it's impact on sleep quality. Moreover effects of neuropathic pain on quality of life and fatigue will be assessed.