SLOW OR GRADUALonset of back pain and stiffness over weeks or months, rather than hours or days.
In summary, the person isYOUNG with GRADUAL onset of pain, and notes that the pain is worse in the MORNING and improves with EXERCISE. By contrast, non-specific or mechanical pain typically comes on RAPIDLY at ANY age as a result of some ill-advised movement, is worse in the EVENING, is EPISODIC in nature and improves with REST.
The diagnosis is often suspected by listening to the patient's story, bearing in mind a combination of the above. The doctor will then note the posture and might notice that the lumbar spine is losing the forward curve and is beginning to flatten out. A referral to a rheumatologist will lead toX-rays being taken of the spine. The rheumatologist will be looking for characteristic changes to the sacroiliac joints. In most cases, more severe bony changes only appear after months or even years of disease. Blood tests may be performed and the 'ESR' (Erythrocyte Sedimentation Rate) or plasma viscosity measured give an indication of the degree of inflammation.
In some cases, where there is still doubt, the rheumatologist might test for the patient's tissue type. The object will be to establish if the person has theHLA B27 antigen. About 8% of the British population share this antigen and 96% of the people who have AS are from this section of the population. In a borderline situation, the B27 positivity or negativity will help to confirm or refute the diagnosis. However, it is not a necessary test and should only rarely be carried out. The test alone can never provide a definite answer.
Although we have been talking about a disease of the spine, pain is not always confined to the back. Some people will have chest pain from time to time. This can be alarming. However, the pain does not come from the heart, but from the joints between the ribs and the back bone, from inflammation in the sternum joints, or from the sites of ligament insertion into the ribs (=intercostal muscles). Many people complain of a "shut-in" feeling because of reduced chest expansion. In these cases the diaphragm does the work of filling the lungs, rather than the rib cage. Physiotherapists aim to improve chest movement. The start of AS often begins with an ache in the buttocks, in the back of the thighs and down the leg and in the lower part of the back. One side is commonly more painful than the other.
The pain arises from the sacroiliac joints where thespine joins the pelvis. The morning stiffness, so often experienced, wears off during the day. Sleep will often be interrupted by early morning pain. It is advisable to get out of bed and walk around and try to free the stiffness with twisting and bending exercises. Sleep deprivation can be a big problem. Increased pain and stiffness can also be experienced after long periods of sitting, for example, in a theatre or cinema, or a long car journey. AS, in its first few years, may cause considerable pain. Anti-inflammatory drugs are usually prescribed to reduce the pain.
Later in life, the disease becomes less active and may go into total remission. Any noticeable stiffening resulting from the condition is not a major handicap, providing the forward stooping posture of the spine has not been allowed to take place. Most people with the condition are able to continue with their normal working lives, a few will have to make adjustments, while some might have to find a new and more suitable occupation. However, rheumatologists tell us that they have long noticed that their spondylitic patients appear to them to be a highly motivated group of people, and indeed, the majority of "patients" lose less time off work than a "normal" individual - the latter being more likely to take off odd days from work with minor ailments. Some people, especially in the early stages of the condition, feel generally unwell. They can lose a considerable amount of weight, feel tired and depressed. The condition is very variable, and no two people appear to be the same. Some complain of feeling feverish, which can also manifest itself in night-time sweating.