Sagittal Orientation Of Facet Joints Research Articles

Pathomechanisms and Predisposing Factors for Degenerative Lumbar Spondylolisthesis: A Narrative Review.

The pathomechanism of degenerative lumbar spondylolisthesis (DLS) is not fully understood and is likely to be multifactorial. The primary cause of DLS likely is age-related degeneration of all of the components of the segments and their surroundings. Subsequently, additional factors, such as anatomical, hormonal, and mechanical stress factors, may drive the spinal segments to DLS. Reported predisposing factors that have shown a consistent association with DLS include older age, female sex, sagittal facet joint orientation, and high pelvic incidence. Future prospective epidemiological studies that include large groups of subjects and use multivariate analyses of the possible predisposing factors are needed.

Spinopelvic Alignment Parameters in Spondylolisthesis Patients Compared to Nonspondylolisthesis Patients

Abstract Objective We aimed at describing spin pelvic alignment features in patients with degenerative spondylolisthesis (DS), in comparison with other patients complaining of low back pain but no evidence of spondylolisthesis on standard standing lateral lumbosacral X-ray. Methods In this prospective descriptive study, patients with low back pain included in two groups of DS and non-DS patients, according to preoperative lumbosacral X-ray in standard standing lateral position. Patient’s demographic characteristics, as well as spinopelvic alignment parameters including pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis, and facet joint orientation, were collected. DS patients were compared with non-DS, age-matched control group. Results DS patients were significantly obese (p = 0.031) and had a high PI (56.39 ± 11.5), SS (38.28 ± 10.32), and PT (18.52 ± 9.11), (p = 0.00, 0.01, 0.04, respectively). Moreover, segmental lordosis at L2–L3, L3–L4, and L5–S1 levels demonstrated a significant increase (p < 0.05). Facet joints at L4–L5 level were located more sagittally (37.5 ± 7.07 vs. 40.71 ± 6.33). Conclusion PI, SS, and PT significantly increase in DS patients compared with non-DS group. Elevated segmental lordosis at high lumbar levels and sagittal orientation of facet joints were other features observed in DS patients.

Association of chronic degenerative arthritis related chronic low back pain with altered lumbar facet joint orientation

ObjectiveTo examine the relationship between changes in lumbar spine facet joint (FJ) orientation and chronic low back pain (CLBP). MethodsWe retrospectively analyzed lumbar spine CT and MRI images of 98 patients referred for localized paraspinal CLBP and 98 age-and sex-matched asymptomatic individuals as controls. They were divided into four age groups (A, <40; B, 41–50; C, 51–60; D, 61–70; and E, 71–80 years old, respectively). FJ orientations were evaluated at the L3-4, L4-5, and L5-S1 lumbar levels. ResultsFJ angle showed a statistically significant more sagittal orientation in CLBP patients than in control groups in lower lumbar spine segments. The overall mean FJ angles in CLBP groups including all age groups combined at L3-4, L4-5, and L5-S1 levels were 32.33 ± 4.5, 36.11 ± 2.9, and 37.4 ± 6.1, degrees, respectively. The FJ angles in control group for all ages were 32.21 ± 3.7, 38.01 ± 4.6, and 40.18 ± 6.8°, respectively. The differences in FJ angle were statistically significant at both L4-5 and L5-S1 levels between the control and the CLBP groups (p < 0.01). The FJ orientation from upper lumbar spine to lumbar sacral junction demonstrated a gradual more coronal orientation transition in all subjects but this trend was significantly less in CLBP patients. The mean FJ angles for the control group at age groups A, B, C, D, and E were 33.52 ± 3.8, 35.7 ± 4.5, 38.25 ± 2.4, 35.49 ± 4.1, and 38.13 ± 5.8, respectively, while those in the CLBP groups were 35.63 ± 2.4, 35.26 ± 3.6, 35.99 ± 5.1, 35.3 ± 4.3, and 35.17 ± 6.7, respectively. ConclusionThere is a significant association between a more sagittal FJ orientation and facetogenic CLBP in lower lumbar vertebral levels. There is also age-dependent decrease in FJ orientation in sagittal plane at lower lumbar spinal levels in control as well as CLBP groups, however, this decrease in the CLBP groups was significantly more pronounced. Whether this change was an adaptive remodeling or alterations associated with chronic FJ osteoarthropathy should warrant further longitudinal studies.

Age-related changes in axial and sagittal orientation of the facet joints: Comparison with changes in degenerative spondylolisthesis

BackgroundDespite facet joints being three-dimensional structures, previous computed tomography and magnetic resonance imaging studies have evaluated facet joint orientation in only the axial plane. Facet joint orientation in the sagittal plane has rarely been studied using these imaging techniques. The aim of this study was to elucidate facet joint orientation in both the axial and sagittal planes on computed tomography. MethodsA total of 568 patients (343 men, 225 women) (excluding orthopedic outpatients) for whom abdominal and pelvic computed tomography scans were obtained at our hospital between September 2010 and October 2012 were included. Mean age was 63 (range 21–90) years. Patients were divided into a degenerative spondylolisthesis group (67 patients; 30 men, 37 women) and a control group (313 patients; 313 men, 188 women). Facet joint orientation was evaluated in the control group according to patient age (≤50, 51–60, 61–70, or ≥71 years). The findings in the control group were then compared with those in the degenerative spondylolisthesis group. The orientation of the lumbar facet joints at each level was measured in the axial and sagittal planes on computed tomography images. ResultsFacet joint angles decreased with age at L4/5 and L5/S1 in women in the axial plane and at L4/5 in men and L3/4 and L4/5 in women in the sagittal plane. The variation in facet joint angle was greatest at L4/5 in women. Patients with degenerative spondylolisthesis showed more sagittally and horizontally oriented facet joints in the axial and sagittal planes; facet tropism showed an association with degenerative spondylolisthesis in the axial plane. ConclusionsThe axial and sagittal orientation of facet joints in the lower lumbar vertebra, especially L4/5, was negatively correlated with age. This finding could help to explain why older people are more prone to degenerative spondylolisthesis.

Hyperlordosis is Associated With Facet Joint Pathology at the Lower Lumbar Spine.

A retrospective study. Our study opted to clarify the remaining issues of lumbar lordosis (LL) with regard to (1) its physiological values, (2) age, (3) sex, and (4) facet joint (FJ) arthritis and orientation using computed tomography (CT) scans. Recent studies have questioned whether LL really decreases with age, but study sample sizes have been rather small and mostly been based on x-rays. As hyperlordosis increases the load transferred through the FJs, it seems plausible that hyperlordosis may lead to FJ arthritis at the lower lumbar spine. We retrospectively analyzed the CT scans of 620 individuals, with a mean age of 42.5 (range, 14-94) years, who presented to our traumatology department and underwent a whole-body CT scan, between 2008 and 2010. LL was evaluated between the superior endplates of L1 and S1. FJs of the lumbar spine were evaluated for arthritis and orientation between L2 and S1. (1) The mean LL was 49.0 degrees (SD 11.1 degrees; range, 11.4-80.1 degrees). (2) LL increased with age and there was a significant difference in LL in our age groups (30 y and below, 31-50, 51-70, and ≥71 y and above) (P=0.02). (3) There was no significant difference in LL between females and males (50 and 49 degrees) (P=0.17). (4) LL showed a significant linear association with FJ arthritis [P=0.0026, OR=1.022 (1.008-1.036)] and sagittal FJ orientation at L5/S1 (P=0.001). In a logistic regression analysis, the cutoff point for LL was 49.4 degrees. This is the largest CT-based study on LL and FJs. LL significantly increases with age. As a novelty finding, hyperlordosis is significantly associated with FJ arthritis and sagittal FJ orientation at the lower lumbar spine. Thus, hyperlordosis may present with back pain and patients may benefit from surgical correction, for example, in the setting of trauma.

Facet tropism and facet joint orientation: risk factors for the development of early biochemical alterations of lumbar intervertebral discs

To assess the glycosaminoglycan (GAG) content of lumbar intervertebral discs (IVD) in healthy volunteers with facet tropism (FT) and sagittal facet joint (FJ) orientation using glycosaminoglycan chemical exchange saturation transfer imaging (gagCEST). Seventy-five lumbar IVDs of twenty-five young, healthy volunteers without any history of lumbar spine pathologies (13 female; 12 male; mean age: 28.0±4.4 years; range: 21-35 years) were examined with a 3T MRI scanner. Orientation of FT and FJ were assessed for L3/4, L4/5 and L5/S1 using standard T2 weighted images. Biochemical gagCEST imaging was used to determine the GAG content of each nucleus pulposus (NP) and annulus fibrosus (AF). Significantly higher gagCEST values of NP were found in volunteers without FT and normal FJ orientation compared to volunteers with FT and sagittal FJ orientation >45° (P<0.0001). GagCEST values were significantly higher in volunteers without FT compared to volunteers with moderate or severe FT (moderate FT: P<0.0001; severe FT: P=0.0033). Volunteers with normal FJ orientation showed significantly higher gagCEST values compared to those with sagittal FJ orientation >45° (P<0.001). We found a significant, negative correlation between gagCEST values and higher angels in sagittal FJ orientation (rho=-0.459; P<0.0001). GagCEST analysis indicated lower GAG values of NP in young volunteers with FT and sagittal orientated FJ, indicating that FT and sagittal orientation of the FJ represent risk factors for the development of early biochemical alterations of lumbar IVDs.

A Prospective Study of Correlation between Clinical Disability and Radiological Features in Degenerative Lumbar Canal Stenosis (LCS)

Introduction The relationship between clinical disability and various parameters such as degree of constriction of dural sac, radiological pelvic parameters, facet joint orientation in patients with degenerative LCS has not been clearly defined. Materials and Methods A total of 50 patients with LCS were selected prospectively and divided into two groups (20 patients responding to conservative therapy and 30 requiring surgery) and compared with 16 controls. Patients were clinically evaluated by Oswestry disability index (ODI), SF-12, and neurogenic claudication outcome score (NCOS). All patients underwent anteroposterior, lateral dynamic radiographs of lumbar spine, and whole spine standing lateral radiograph. The spinopelvic parameters measured were spinosacral angle, thoracic kyphosis, lumbar lordosis, pelvic incidence, sacral slope, and pelvic tilt. Dural sac cross-sectional area, lateral recess angle and height, and facet joint orientation were assessed in MRI. Results Between conservative and operated group, the mean ODI score (55.5 vs. 62.99, p = 0.014) and NCOS (37.7 vs. 29.47, p = 0.06) were significantly different. Dural sac area significantly differed ( p &lt; 0.001) between control (113.97 ± 57.58), conservative (47.57 ± 24.77), and operated groups (20.66 ± 14.49). NCOS had significant positive correlation with dural sac area ( r = 0.296, p = 0.037) than ODI. In patients with degenerative spondylolisthesis, there was a significant sagittal orientation of facet joints, high pelvic incidence (58.79 vs. 50.57, p = 0.047), and an increased pelvic tilt (18.99 vs. 11.25, p = 0.045). Conclusion Degree of dural sac stenosis corresponds to clinical disability and NCOS is a better indicator of dural sac compression than ODI score. LCS patients with sagittal facet orientation, high pelvic incidence, and high pelvic tilt develop spondylolisthesis. Disclosure of Interest None declared

Increased pelvic incidence may lead to arthritis and sagittal orientation of the facet joints at the lower lumbar spine

BackgroundCorrect sagittal alignment with a balanced pelvis and spine is crucial in the management of spinal disorders. The pelvic incidence (PI) describes the sagittal pelvic alignment and is position-independent. It has barely been investigated on CT scans. Furthermore, no studies have focused on the association between PI and facet joint (FJ) arthritis and orientation. Therefore, our goal was to clarify the remaining issues about PI in regard to (1) physiologic values, (2) age, (3) gender, (4) lumbar lordosis (LL) and (5) FJ arthritis and orientation using CT scans.MethodsWe retrospectively analyzed CT scans of 620 individuals, with a mean age of 43 years, who presented to our traumatology department and underwent a whole body CT scan, between 2008 and 2010. The PI was determined on sagittal CT planes of the pelvis by measuring the angle between the hip axis to an orthogonal line originating at the center of the superior end plate axis of the first sacral vertebra. We also evaluated LL, FJ arthritis and orientation of the lumbar spine.Results596 individuals yielded results for (1) PI with a mean of 50.8°. There was no significant difference for PI and (2) age, nor (3) gender. PI was significantly and linearly correlated with (4) LL (p = < 0.0001). Interestingly, PI and (5) FJ arthritis displayed a significant and linear correlation (p = 0.0062) with a cut-off point at 50°. An increased PI was also significantly associated with more sagitally oriented FJs at L5/S1 (p = 0.01).ConclusionPI is not correlated with age nor gender. However, this is the first report showing that PI is significantly and linearly associated with LL, FJ arthritis and more sagittal FJ orientation at the lower lumbar spine. This may be caused by a higher contact force on the lower lumbar FJs by an increased PI. Once symptomatic or in the event of spinal trauma, patients with increased PI and LL could benefit from corrective surgery and spondylodesis.

Contribution of sagittal orientation of facet joints and disc degeneration to degenerative spondylolisthesis in lumbar spine: A finite element research

目的 探讨小关节矢状化与椎间盘退变间的关系及其对退变性腰椎滑移的作用和意义.方法 采用一种新型CAD方法精确构建65°小关节角、45°小关节角、25°小关节角与正常椎间盘、轻度退变椎间盘、重度退变椎间盘相组配的9种腰椎L4-L5活动节段有限元模型.生理压缩载荷下,分别对9种有限元模型的生物力学参数进行测试.结果 与小关节角45°和25°有限元模型相比,小关节角65°有限元模型的矢状方向椎体前移位增加,关节突、峡部等效应力和关节突水平方向接触力明显增加;小关节角65°有限元模型的终板膨出减小,纤维环基质应力增加.与正常有限元模型相比,椎间盘轻度退变有限元模型刚度下降,小关节突及峡部应力轻度增加.9种有限元模型中,轻度退变椎间盘结合小关节角65°有限元模型的抗前剪力能力最差.结论 小关节角矢状化既是退变性腰椎滑移的原发诱因,又是局部应力变化导致关节突再塑形的继发病理改变,矢状型小关节腰椎活动节段矢状方向内在不稳定性受椎间盘退变程度的影响,椎间盘退变对小关节角矢状化无明显促进作用。

Orientation and Osteoarthritis of the Lumbar Facet Joint

Several studies have shown an association between sagittal orientation of the facet joint and degenerative spondylolisthesis. There is currently no information available on the association between orientation of the facet joint and osteoarthritis. This study examined the association between orientation and osteoarthritis of the lumbar facet joints. One hundred eleven consecutive patients underwent plain radiography and magnetic resonance imaging. These patients were divided into two groups: No Degenerative Spondylolisthesis Group (98 patients) and Degenerative Spondylolisthesis Group (13 patients). In the No Degenerative Spondylolisthesis Group, segments with higher grades of osteoarthritis showed more sagittal orientation of the facetjoints at the L3-L4 and L4-L5 levels. The facet joint was oriented significantly more sagittally in the Degenerative Spondylolisthesis Group than in the No Degenerative Spondylolisthesis Group at the L4-L5 and L5-S1 levels. The severity of facet joint osteoarthritis was significantly higher in the Degenerative Spondylolisthesis Group than in the No Degenerative Spondylolisthesis Group at the L3-L4, L4-L5, and L5-S1 levels. A significant association was found between sagittal orientation and osteoarthritis of the lumbar facet joints, even in patients without degenerative spondylolisthesis. Facet joint osteoarthritis, rather than spondylolisthesis, is the pathoanatomic feature that is associated with sagittal orientation of the facet joints in patients with degenerative spondylolisthesis.

Predisposing factors in degenerative spondylolisthesis

We report a prospective study analysing whether possible factors predisposing to degenerative spondylolisthesis (DS) must be present concomitantly in order to cause vertebral slipping. Standard and flexion-extension radiographs were obtained from 27 patients with DS and 27 without spondylolisthesis. The level of the intercrestal line, the lumbosacral angle, the presence of sacralization of L5 and vertebral motion at the L4-L5 level were assessed. Facet joint orientations were measured on CT scans. Only facet joint orientation and vertebral motion at the spondylolisthetic level were significantly different in patients with DS compared with controls. Facet joints were oriented more sagittally both at the spondylolisthetic level and at the levels above and below. An inverse linear correlation was found between the sagittal orientation of facet joints and the mobility of the slipped vertebra. Abnormal sagittal orientation of facet joints and hypermobility of the spondylolisthetic vertebra appear to play major roles among possible factors predisposing to DS. Both factors should be considered in the planning of surgical treatment.

Postoperative Spondylolisthesis at L4-5

Thirty-three patients underwent decompression without fusion at the L4-5 level for spinal stenosis or degenerative spondylolisthesis. Using preoperative and 1-year postoperative lateral lumbar spine radiographs, the incidence of postoperative spondylolisthesis of greater than 5% was found to be 58%. Computed tomographic scans were used to analyze the presurgical facet joint morphology and facet joint-pedicle spatial relationship. This allowed calculation of the facet joint orientation for each side; the coronal dimension of each facet joint; the amount of the facet joint coronal dimension removed if a decompression was performed up to the medial border of the L5 pedicle (facet joint reduction); and the residual coronal dimension of facet joint after such a decompression (residual facet joint). The lateral radiographs were analyzed for presurgical disc height and the presence of traction spurs or spondylophytes. A well-maintained disc height was associated with an increase slip (7.47%) compared with those cases with a narrow or complete loss of disc space before surgery (4.84% P < 0.1 trend). Presence of spondylophytes was associated with a reduced tendency to slip. When spondylophytes were controlled for there was a significant relationship between slip of greater than 10% and sagittal facet joint orientation. Although there was a lesser residual facet joint after decompression in the group that slipped these values were not statistically significant. This study suggests that the development of postoperative spondylolisthesis is related to facet joint orientation and dimensions, rather than the absolute amount of joint removed. The stabilizing effects of reduced disc height and spondylophytes were confirmed.