Congenital Spondy: Results from dysplagia of the 5th lumbar and sacral arches and z-joints.
Isthmic Spondy: This is a defect in the pars interarticularis. This can either be by an acute fracture, stress fracture, or elongation. In severe cases, a soft tissue depression above L5 can be palpated.
Degenerative Spondy: Affects older people and most commonly at L4-L5.
Traumatic Spondy: Either a fracture or acute dislocation of the zygapophysial joint (rare).
Pathologic Spondy: May result from a systemic disease causing weakness of the pars, pedicle, or z-joint. May also result from a tumor.
Spondy Aquisita: Slip caused by surgical disruption of ligaments, bones, or disk.
Degenerative Spondy is the type that is most encountered by a PT and there are different causes of this type. The intervertebral disk integrity is lost as we age and this is commonly an underlying factor contributing to degenerative spondy. The disk functions to help to prevent slippage and as people age, this disk becomes unstable and the ability to oppose shearing forces is decreased.