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Facet Joint Orientation and Tropism in Lumbar Degenerative Disc Disease and Spondylolisthesis

Introduction Back pain is one of the most common reported health problems in elderly. Two common causes of back pain were included in this study, degenerative disc disease (DDD) and spondylolisthesis (DS). Since facet joint is one of many structures that provide stability for spine, so this study will focus on the facet joint angle of patient. The association between lumbar facet joint angle and tropism in DDD and DS remain unclear. Materials and Methods The angle and tropism of lumbar facet joint were retrospectively studied with magnetic resonance imaging (MRI) in 180 subjects to determine whether there is a difference between degenerative diseases. MRI of patients with DDD, DS, and control group at facet joint between L3-4, L4-5, and L5-S1 levels were measured in axial view that can clearly see facet joint (60 subjects in each group). Results There is no different in facet joint angle in DDD (44.1 ± 11.9) and control (45.6 ± 8.9) but different in DS (40.1 ± 10.7) and control group (p = 0.010) at L4-5 level. Facet tropism shows different between degenerative and control groups (mean different = 2.9 degrees, p = 0.007 in DDD and mean different = 2.2 degrees, p = 0.046 in DS) at L4-5 level. Conclusion This study confirms a significant different between facet joints angle at L4-L5 in DS and normal population. Facet tropism in DDD and DS were shown significantly different to normal population. Additional, longitudinal studies are needed to understand the clinical significant in relationship between facet joint angle and tropism in spinal degenerative diseases. Disclosure of Interest None declared References Boden SD, Riew KD, Yamaguchi K, Branch TP, Schellinger D, Wiesel SW. Orientation of the lumbar facet joints: association with degenerative disc disease. J Bone Joint Surg Am 1996;78(3):403–411 Kalichman L, Suri P, Guermazi A, Li L, Hunter DJ. Facet orientation and tropism: associations with facet joint osteoarthritis and degeneratives. Spine 2009;34(16):E579-E585 Don AS, Robertson PA. Facet joint orientation in spondylolysis and isthmic spondylolisthesis. J Spinal Disord Tech 2008;21(2):112–115