123Axial Spondyloarthritis
Clinical Picture of Axial SpA
The most signifi cant clinical symptoms of patients with axSpA are back pain and
peripheral, usually asymmetric oligoarthritis of the lower limbs and enthesitis [ 1 ].
Because of the underlying infl ammation, the back pain is often worse at night
(nocturnal pain) and may lead to various degrees of morning stiffness (>30 min).
Major concerns of patients with axSpA are spinal pain and stiffness either due to
infl ammation or ankylosis in the axial skeleton, which may also result in impaired
spinal mobility and decreased physical function. These impairments often lead to
limitations of activities and social participation [ 8 ]. Reduced work participation is
of major importance for our patients, who classically start with the fi rst symptoms
of the disease in the second or third decade of life [ 9 ].
Assessment of Patients with axSpA
The clinical features to be assessed in patients with axSpA include symptoms,
disease activity, physical function, and HRQoL. The ASAS group has defi ned a
number of core sets of areas of disease that should be measured in different situa-
tions, including the ASAS cores set for clinical record keeping (Table 5.2 ) [ 10 ].
Five out of the eight domains are patient-reported outcomes and will be addressed
in the following chapters. Although enthesitis is frequent, no validated PRO is
available for this disabling aspect. Validated indices comprises physical examina-
tion of the entheses with documentation of pain and tenderness.
Table 5.2 ASAS core set for clinical record keeping
Domain Instrument
Physical function BASFI or Dougados Functional Index
Pain VAS/NRS past week in spine, at night, due to AS and VAS/NRS
past week, in spine due to AS
Spinal mobility Chest expansion and modifi ed Schober and occiput-to-wall
distance and lateral spinal fl exion
Patient global assessment VAS/NRS past week
Morning stiffness Duration of morning stiffness in spine past week
Fatigue VAS/NRS past week
Peripheral joints and entheses Number of swollen joints (44 joint count). Validated enthesis
indexes
Acute phase reactants ESR
Adapted from Ref. [ 10 ]
Domains in italics are PRO
AS ankylosing spondylitis, BASFI Bath AS Functional Index, ESR erythrocyte sedimentation rate,
NRS numerical rating scale, VAS visual analogue scale
5 PROMs for Spondyloarthritis