The facets semi-sagittal orientation optimizes movement in all directions. A variation in the usual plane of the articulation usually targeting the L5-S1 level. Lumbo-sacral facet tropism may be a source of abnormal biomechanics even though research needs to concur with this theory.
Most occurrences are unilateral.
This condition usually arises from chronic postural hyperlordosis and regional loss of discal spacings. Baastrup s disease maybe a source of symptoms as a result of local inflammation.