Study: NCT04485078

Intervention type: DIAGNOSTIC_TEST
Intervention: Pressure pain threshold
Description: The PPT assessments of spine will be performed over the spinous process and 2 cm right and left side of the corresponding spinous process. The regional PPT scores will be composed from sum of all PPT values for related segments at spine. The sacroiliac PPT scores will be obtained bilaterally from four measurement points; the first point is located 1 cm medially and caudally from spina iliaca posterior superior (SIPS) and 3 more laterally, medially and cranially.The left trapezius muscle will be used to evaluate distant control point .The 1 cm2 algometer probe will be placed vertically in the each selected point and pressure will be increased with 0.1 kg/sc until the participant reporting pressure became painful. The pressure value at which the pain is first felt will be accepted as the PPT of that point.

Intervention type: DIAGNOSTIC_TEST
Intervention: Pressure pain threshold
Description: The PPT assessments of spine will be performed over the spinous process and 2 cm right and left side of the corresponding spinous process. The regional PPT scores will be composed from sum of all PPT values for related segments at spine. The sacroiliac PPT scores will be obtained bilaterally from four measurement points; the first point is located 1 cm medially and caudally from spina iliaca posterior superior (SIPS) and 3 more laterally, medially and cranially.The left trapezius muscle will be used to evaluate distant control point .The 1 cm2 algometer probe will be placed vertically in the each selected point and pressure will be increased with 0.1 kg/sc until the participant reporting pressure became painful. The pressure value at which the pain is first felt will be accepted as the PPT of that point.

Intervention type: DIAGNOSTIC_TEST
Intervention: Temporal summation
Description: TS will be evaluated over the trapezius muscle, sacroiliac joints, C7, T6, and L3 levels at spine with manuel algometer. TS scores will be calculated for each spine level as the sum of three values which measured over the spinous process and 2 cm right and left side of corresponding level. In the evaluation of TS, a pressure as much the PPT value of each point will be applied with pain pressure algometer ten times with a 1-second interstimulus interval. Patients will be asked to rate their pain using on a 0 to 10 visual analogue scale (VAS) at 0, 5, and 10 seconds. TS will be calculated by subtracting the rating at 0 seconds from the rating at 10 seconds. The point that is located 1 cm medially and caudally from SIPS was used for SI joint TS measurement on both sides.

Intervention type: DIAGNOSTIC_TEST
Intervention: Temporal summation
Description: TS will be evaluated over the trapezius muscle, sacroiliac joints, C7, T6, and L3 levels at spine with manuel algometer. TS scores will be calculated for each spine level as the sum of three values which measured over the spinous process and 2 cm right and left side of corresponding level. In the evaluation of TS, a pressure as much the PPT value of each point will be applied with pain pressure algometer ten times with a 1-second interstimulus interval. Patients will be asked to rate their pain using on a 0 to 10 visual analogue scale (VAS) at 0, 5, and 10 seconds. TS will be calculated by subtracting the rating at 0 seconds from the rating at 10 seconds. The point that is located 1 cm medially and caudally from SIPS was used for SI joint TS measurement on both sides.

Intervention type: DIAGNOSTIC_TEST
Intervention: Conditioned pain modulation
Description: First stimulus will be applied to trapezius with the pressure that induced a pain intensity of 4 point on a 10 point VAS as called a test stimulus. After that the right hand of the patient will be immersed in 70C water for 20 seconds to create a conditioning stimulus. Second test stimulus with the same intensity of first one will be applied to trapezius after the conditioning stimulus and patients will be asked to rate their pain. If the patients cannot hold their hand in the water for 20 seconds, the test stimulus will be applied immediately after the patients removed their hands out of water. The ratio between the first and second VAS values multiplied by 100 will be defined as CPM score

Intervention type: DIAGNOSTIC_TEST
Intervention: Central Sensitization Inventory
Description: Standardized questionnaire to determine the level of central sensitization

Intervention type: OTHER
Intervention: Bath Ankylosing Spondylitis Disease Activity Index
Description: Standardized questionnaire to determine the level of disease activity in AxSpa patients

Intervention type: OTHER
Intervention: Ankylosing Spondylitis Quality of Life
Description: Standardized questionnaire to investigate the quality of life in AxSpa patients

Intervention type: OTHER
Intervention: Istanbul Low Back Pain Disability Index
Description: Standardized questionnaire to investigate the disability

Intervention type: OTHER
Intervention: Beck Depression Inventory
Description: Standardized questionnaire to investigate the depression

Intervention type: OTHER
Intervention: Fatigue Severity Scale
Description: Standardized questionnaire to investigate the fatigue

Intervention type: OTHER
Intervention: Pittsburgh Sleep Quality Index
Description: Standardized questionnaire to investigate the sleep quality and disturbance

Intervention type: OTHER
Intervention: Fibromyalgia Rapid Screening Tool
Description: Standardized questionnaire to detect fibromyalgia

Intervention type: OTHER
Intervention: Visual analogue scale
Description: global pain score on a 0 to 10