Correlations Between Facet Tropism, Joint Mobility and Degree of Displacement in Patients with Low Grade Spondylolisthesis.

AIM: To compare lumbar X-ray and magnetic resonance imaging (MRI) findings, and to identify the factors associated with joint instability in cases with lumbar spondylolisthesis.

MATERIAL AND

METHODS

We performed a retrospective and observational study of patients with a confirmed diagnosis of lumbar or lumbosacral low-grade spondylolisthesis at a single level. Preoperative X-ray and MRI examinations were evaluated. Statistical analysis was performed using Fisher's exact test and Kappa statistics.

RESULTS

The present study comprised 59 patients. Of these, 62% had Modic changes on MRI. Degenerative and isthmic spondylolisthesis was found in 49.2% and 50.8% of patients, respectively. All patients had degenerative disc changes at the level of the listesis. Moderate and severe facet asymmetry was observed 18 (30.5%) and three (5.1%) patients, respectively. Neutral facets were observed in 64.4% of patients. Dynamic X-ray detected segmental mobility in 52.5% of the cases. There was a negative correlation between the presence of tropism and joint mobility (p=0.03). Further, the degree of listesis was negatively correlated with the presence of FT (p=0.02). Substantial agreement (91.52%) was observed between MRI and X-ray examinations (Kappa, 0.81; CI, 0.66-0.97).

CONCLUSION

MRI was sufficient for the diagnosis of lumbar spondylolisthesis and dynamic lumbar imaging was important in defining segmental mobility. In addition, facet tropism appeared to have a protective effect on instability.