Health History and Physical Exam
One of the first steps on the path to a diagnosis of ankylosing spondylitis (AS) is a physical exam and medical history. During a medical history, the physician or nurse will ask about a patient’s personal health experiences, as well as family health conditions. Having a family member who has AS, or related conditions, increases a person’s risk of developing it. Any symptoms the patient is experiencing are important to note at this time, such as areas of pain or stiffness, how long the pain has been present, anything that relieves the pain or stiffness (like activity), or fatigue.1,2
During a physical exam, a doctor examines the patient’s body for signs of disease. The doctor’s exam will include a visual inspection (looking), palpation (feeling), ascultation (listening, often with a stethoscope), and percussion (producing sounds through tapping). Any points of inflammation are evaluated during the physical exam. Doctors may also want to evaluate a patient’s flexibility in their spine.1
Typical symptoms of ankylosing spondylitis
While AS has variability in how it manifests in different people, a common early symptom is low back pain, caused by inflammation of the sacroiliac (SI) joints, located between the base of the spine and the pelvis. This inflammation is called sacroiliitis. The low back pain associated with sacroiliitis and AS can appear gradually and cause stiffness that is worse with rest and improves with movement. AS also causes chronic back pain, such as back pain that has been present for more than three months.1,4
However, not everyone with AS has low back pain as their first symptom. Women in particular seem to have differences than men with AS on symptoms. Some women with AS have symptoms begin in other areas, such as the neck. Pain and inflammation from AS can also occur in other joints, such as the hips, shoulders, chest, or heels.1
Mobility and range of motion
AS can cause stiffness, and as the condition progresses, joints may become fused together, which can impact a person’s range of motion and mobility. During a physical examination, the doctor may perform different tests to assess the patient’s range of motion. Some of the tests which may be used include:
- Schober’s test, which measures the degree of flexibility in the low back (lumbar spine) by having the patient bend over (reaching towards the feet)5
- FABER (Flexion, Abduction, External Rotation) test, also known as Patrick’s test, which can evaluate problems in the SI joints or hips by having a patient lie down, bend their knee, placing the foot on the opposite knee, and rotating the bent leg outwards6
Quality of life
AS can also have a significant impact on a person’s quality of life, and there are several different quality of life assessments that may be used by healthcare professionals to assess how a person’s life is affected, such as the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and the Ankylosing Spondylitis Disease Activity Score (ASDAS). Understanding how the symptoms are impacting a person’s ability to engage in daily activities can help doctors determine the severity of a disease. These measurements help determine treatment approaches.
Other tests used to make a diagnosis of ankylosing spondylitis
In addition to a symptom history and physical exam, other tests which may be used to help make a diagnosis of AS include blood tests and imaging, like x-ray or magnetic resonance imaging (MRI) scan. While there is not a blood test that can determine if a person has AS, blood tests may be used to rule out other conditions or to assess inflammatory markers.
Imaging scans may be used to determine the inflammation or damage to joints.1