Optimal Cut-Off Value of the Superior Articular Process Area as a Morphological Parameter to Predict Lumbar Foraminal Stenosis

Abstract

Background. We devised a new morphological parameter called the superior articular process area (SAPA) to evaluate the connection between lumbar foraminal stenosis (LFS) and the superior articular process. Objective. We hypothesized that the SAPA is an important morphologic parameter in the diagnosis of LFS. Methods. All patients over 60 years of age were included. Data regarding the SAPA were collected from 137 patients with LFS. A total of 167 control subjects underwent lumbar magnetic resonance imaging (MRI) as part of a routine medical examination. We analyzed the cross-sectional area of the bone margin of the superior articular process at the level of L4-L5 facet joint in the axial plane. Results. The average SAPA was 96.3 ± 13.6 mm2 in the control group and 128.1 ± 17.2 mm2 in the LFS group. The LFS group was found to have significantly higher levels of SAPA (p < 0.001) in comparison to the control group. In the LFS group, the optimal cut-off value was 112.1 mm2, with 84.4% sensitivity, 83.9% specificity, and AUC of 0.94 (95% CI: 0.91–0.96). Conclusions. Higher SAPA values were associated with a higher possibility of LFS. These results are important in the evaluation of patients with LFS.

Usefulness of the Inferior Articular Process’s Cross-Sectional Area as a Morphological Parameter for Predicting Central Lumbar Spinal Stenosis

“…This value is higher than that of the IAPCSA. The cause of the difference between these two values is presumably that the CSA of the superior articular process is larger than that of the IAP [10]. Ogikubo et al have reported a significant relationship between shorter walking distances and a smaller dural sac CSA [11].…”

“…In this research, we analyzed the IAPCSA from LS-MRI images and visualized IAP in transverse T1-weighted LS-MRI. LS-MRI provides a high-quality view of the IAP and IAP hypertrophic changes [10,21]. Our research had a few weaknesses.…”

“…Our study included individuals above the age of 50. This is because only minimal cartilage changes are correlated with facet degeneration in those aged younger than 50, and that the hypertrophic change in osteoarthritis advances with the aging process [10]. In this research, we analyzed the IAPCSA from LS-MRI images and visualized IAP in transverse T1-weighted LS-MRI.…”

“…CLSS is characterized by lumbar spinal canal narrowing that is caused by proliferation of the superior articular process, mechanical compression of the spinal nerve roots, hyperostosis of the vertebral posterior border, a hypertrophied ligamentum flavum, and protrusion of the intervertebral disc [7]. Previous research has demonstrated that morphological features, including the superior articular process's cross-sectional area (CSA), the spinal canal's CSA, the dural sac's CSA, and the ligamentum flavum's thickness are associated with greater incidences of CLSS [8][9][10][11]. To date, however, no study has reported the effect of inferior articular process (IAP) hypertrophy on CLSS.…”

Optimal cut-off points of lumbar pedicle thickness as a morphological parameter to predict lumbar spinal stenosis syndrome: a retrospective study

“…Lumbar spinal stenosis syndrome (LSSS) is a common cause of structural abnormalities associated with the spinal cord, including narrowing of the spinal canal. 1 Patients usually present with leg pain, with intermittent claudication or low back pain manifesting as a primary clinical feature. LSSS seriously affects patients’ quality of life, increasing not only the economic burden on the society but also the morbidity and suffering of patients interfering with their ability to work.…”