Assertion: spondylolisthesis's vertebra | /r/CapableOf | slide on subjacent vertebra
Facets:
value: forward
type: MANNER
Source sentences:
text: Degenerative Spondylolisthesis occurs when a preexisting forward misalignment causes the upper vertebra to slide forward on the subjacent vertebra and the tendons, muscles and the ligaments yield under the pressure, leading to ligament instability.