Ankylosing Spondylitis
A chronic inflammatory arthritis of the axial skeleton
- may also affect the periphery
- may progress to complete spinal fusion
Disease onset & progession characteristics…
Onset
- Insidious onset
- Pain & stiffness in low back & SIJ
- START: in SIJ joints - more stiffness than pain
- Pain is inflammatory
Worse in the morning
Stiffness & pain last at least 30-40 minutes (does not go past 1 hr - contrast to RA)
Sleep disturbed by pain (nocturnal back pain)
Progression
- Variable course: Mild self-limiting to severe disease w/ complete spinal fusion
- Periods of exacerbation and remission
- Progress from caudal to cephald (bottom up)
S/S
(4)
- Low back and glute pain & stiffness
- Loss of ROM
Mostly spine but can also occur in peripheral joints (girdle mm)
Ex. Shoulder FLEX > not only affected b/c of AS in the shoulder BUT also if T/S is affected (most cases) > T/S = more kyphotic positions - fusion in FLEX - Postural abnormalities
Posture does matter - want to go into reverse postures that they are going to be fixated in - Tenderness over sites of enthesitis
Insertion of a mm - where ever it inserts is tender
itis = inflammation of the mm at that point
Postural changes in advanced disease…
(5)
- INC thoracic kyphosis
- DEC lumbar lordosis
- Eye upward gaze d/t C/S flexion deformity
- Fixed thoracic cage
Going to act like a restrictive disease = more shallow & quicker breaths - Hip flexion & knee flexion in an attempt to maintain upright posture may lead to contractures
To create a new BOS - flex hip & knee to make sure Cog stays w/in BOS
S/S: Systemic
(4)
- Fatigue
INC metabolic activity d/t the disease process & fixed rib cage = breathing is affected - deconditioning as a result - Eye involvement
Anterior uveitis (iritis) - Cardiovascular Involvement
INC risk of CV morbidity & mortality
Heart pathologies like electrical irregularities (scarring & inflammation) = can affect HR - slow it down - Pulmonary Involvement
Functional lung impairment - Not getting typical bucket handle expansion of rib cage = restrictive = cannot take as much air in
Radiographic Findings
(5) + details
- Sacroiliitis - HALLMARK signs
Early Stage:
- Irregular SIJ spaces (pseudo-widening)
- Subchondral bone erosions
- Increased sclerosis around SIJ
Advantage Stage:
- SIJ thin or not visible - becomes more “black” - not as opaque - Syndemophytes - bone growth inside a ligament
“Bamboo” Spine = bony growth in the outer fiber ring of annulus fibrosis
More common
“Railroad Track” Spine = affecting the Longitudinal ligaments - Thoracic Kyphosis
- Enthesitis
Plantar fascia insertion
ITB insertion - may see this on x-ray of hips & spine - Arthritis
Hip - may require a TKA in later stages
Outcome Measures: Physical Assessment & Self-Report Tools
Physical Assessment:
Bath ankylosing spondylitis metrology index (BASMI)
1. Cervical rotation
2. Tragus to wall - C/S retraction w/ head, back, feet against the wall
3. Modified Schober - 10 cm above PSIS & 5 cm below PSIS > measure b/t lines in standing & bend forward (L/S flexion)
4. Finger to floor lateral flexion - Keep hands against the sides - everything else is touching the wall
5. Intermalleolar distance - SUPINE - ask pt to ABDUCT legs as far apart as they can & use tape to measure to each MEDIAL malleolus
Chest Expansion
Self-report Tools:
- Bath ankylosing spondylitis disease activity index (BASDAI)
- Bath ankylosing spondylitis functional index (BASFI)
Modified New York Criteria
Used to Dx AK - 2 Criterias + Dx
Clinical Criteria
1. Low back pain present for >3 months; improved by exercise but not relieved with rest
** Rest does not help - feel better when they are moving - encourage & educate patient
2. Limitation of L/S motion in both the sagittal & frontal planes
3. Limitations of chest expansion relative to normal values for age & sex
Radiological criterion
1. Sacriliitis on x-ray
Diagnosis
1. Definite ankylosing spodylitis:
If the radiological criterion is present (sacroiliitis) + at least one criterion
2. Probable ankylosing spondylitis:
If all 3 clinical criteria are present alone, or if the radiological criterion is present but no clincial criteria are present
