Assertion: ankylosing spondylitis | /r/HasSubevent | fusing of the vertebra
Facets:
value: in the lower back
type: LOCATION
value: over time
type: TEMPORAL
Source sentences:
text: Over time, ankylosing spondylitis can lead to fusing of the vertebra in the lower back.
text: Ankylosing spondylitis is a kind of arthritis that mainly affects the spine, leading to the fusing of vertebrae.