Ankylosing spondlytis is a slow onset disease. Sometimes even the patient does not know that he has a disease for years together because it starts with a vague pain here and there, it may be a neck pain a lower back pain, on the middle of the back or on the sides of the chest, on and off pain and it stays for one or two days and then disappears. So patients usually neglect the symptoms but gradually the patient had more and more pain but more than the pain, it is the stiffness. So morning stiffness is the pathognomonic feature or the definite feature of this Ankylosing spondlytis. So the patient when he gets up in the morning, his entire back that is the lower back is totally stiff. He cannot get up from the bed. He has to lie down in the bed for 10 15 minutes and then slightly roll and then get up. This stiffness gradually disappears once he goes for a normal routine activity. Usually by 9am or 10 am, the pain comes down. When he is doing the daily activities, he does not notice the pain or the stiffness, but once again in the night, when he lies down, the pain restarts. Pain is more when he turns around in the bed and it will aggravate in the morning when he gets up from the bed, These patients will have stiffness from the neck to the lower back, He find s it difficult to touch his toes or bend downwards to reach something. These are the major symptoms of ankylosing spondlytis. If you want to test this, you need to do investigations like xrays. Xrays we see the narrowing of the sacroiliac joints, where the ileum meets. So there will be some narrowing or sclerosis or dense bone formation around the sacroiliac joints. This disease can be diagnosed by blood examination or xray. In blood examination, there is an increase in ESR, or Erythrocytic Sedimentation Rate and C reactive Proteins, CRP and some of them have a hereditary connection in the form of a gene called as the HLA B 27. So detection of that gene will also be helpful in diagnosing Ankylosing spondlytis. So in xrays we see the narrowing of the sacroiliac joints or sclerosis or dense bone formation around the sacroiliac joints. Sacroiliac joints is a joint in the pelvis where both the iliac bones meet and as the disease advances, there is a bamboo pattern of the vertebra, the vertebra fusing with each other. It can be in the cervical spine, in the thoracic spine or in the lumbar spine, you notice what is called as the bamboo spine. The intervertebral disc gradually turns into bones and gradually the entire spine turns into an entire bone without any intervening disks, in MRI also we can screen the sacroiliac joints, and see the edema and later on the sclerosis and fusion of the sacroiliac joints.