Orientation Of Lumbar Facet Joints Research Articles

Decade-Wise Computed Tomography-Based Morphometric Measurements of a Single Lumbar Spinal Motion Segment L4-5.

A spinal motion segment comprises facet joints and intervertebral disc. A complex interplay of biomechanical factors occurs between them with degeneration giving rise to numerous pathological conditions. We conducted a study to find a correlation between facet joint orientation and intervertebral discs with age. A cross-sectional study of 203 consecutive subjects undergoing a computed tomography scan of abdomen and pelvis were included. Subjects were divided into 5 groups based on age (group I: 18-30 years; group II: 31-40 years; group III: 41-50 years; group IV: 51-60 years; group V: 61-70 years). Using 3-dimensional reconstruction images, orientation of lumbar facet joints at the L4-5 level was measured. Similarly, adjacent disc heights at L3-4 and L4-5 were measured and their ratio was documented. The study included 106 males and 97 females. A positive correlation was noted between age and sagittal facet orientation until age 60 years. However, after age 60 years, a negative correlation with age was seen, which was statistically significant. Similarly, the disc height ratios show a progressive decline in their values with age. However, this decline was statistically significant only after age 60 years. The gradual change of facet joint orientation from sagittal to coronal as the age crosses from 30 to 60, to beyond 60, with a simultaneous and parallel diminishing in the disc height probably is one of the attributes of the phenomenon of autostabilization of a motion segment.

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.

The Effects of Orientation of Lumbar Facet Joints on the Facet Joint Contact Forces: An In Vitro Biomechanical Study.

A biomechanical human cadaveric study. The aim of this study was to measure L2-L3 facet joint contact forces in a flexibility test using thin film electroresistive sensors, and facet joint orientation on computed tomographic (CT) scan images, to examine the effects of orientation of lumbar facet joint on the facet joint contact forces. Biomechanically, the bilateral facet joints play a critical role in maintaining stability of the lumbar spine. The effect of orientation of lumbar facet joints on the contact forces remains unknown. Eight human cadaveric lumbar spine specimens (L2-L3) were tested by applying a pure moment of ±7.5 Nm in three directions of loading (flexion-extension, lateral bending, and axial rotation) with and without a follower preload of 300 N. The orientation of the lumbar facet joints at the L2-L3 was measured on axial CT scans. Bilateral facet contact forces were measured during flexibility tests using thin film electroresistive sensors (Tekscan 6900). The average total peak facet loads was 66 N in axial rotation, 27 N in extension, and 20 N in lateral bending under a pure moment. Under a pure moment with a follower preload of 300 N, the average total peak facet loads was 53 N in axial rotation, 43 N in extension, and 24 N in lateral bending. The facet joint forces were correlated positively and significantly with the orientation in all directions with and without a compressive follower preload (P < 0.05). In addition, the facet joint contact forces at neutral position with a follower preload were correlated positively with the orientation (rs = 0.759, P = 0.001). This study identified that the greater coronal orientation of lumbar facet joints is, the higher the facet joint contact forces are. 3.

The Variation in the Lumbar Facet Joint Orientation in an Adult Asian Population and Its Relationship with the Cross-Sectional Area of the Multifidus and Erector Spinae

Study DesignCross-sectional study of healthy volunteers.PurposeWe aimed to investigate the variation in the lumbar facet joint orientation in an adult Asian population. The relationship between the facet joint orientation and muscle cross-sectional area (CSA) of multifidus and erector spinae was also clarified.Overview of LiteratureSeveral studies have reported that lumbar pathologies, such as lumbar spondylolysis and degenerative spondylolisthesis, were related to the horizontally shaped lumbar facet joint orientation at the lower lumbar level. However, data regarding variations in the facet joint orientation in asymptomatic subjects have not been well documented.MethodsIn 31 healthy male adult Asian volunteers, the facet joint orientation and CSA of multifidus and erector spinae were measured using magnetic resonance imaging at the L4–5 and L5–S1 levels. Variation in the facet joint orientation was examined using coefficients of variation (CV). Pearson's product-moment coefficient was used to investigate the relationship between the facet joint orientation and CSA of multifidus and erector spinae.ResultsLumbar facet joint orientation had a wider range of variation at L5–S1 (CV=0.30) than at L4–5 (CV=0.18). The L4–5 facet joint orientation had a weak but significant correlation with the CSA of erector spinae (r=0.40; p=0.031). The CSA of the multifidus had no relationship with the facet joint orientation at the L4–5 (r=0.19; p=0.314) and the L5–S1 level (r=0.19; p=0.312).ConclusionsThe lumbar facet joint orientation was found to have a wide variation, particularly at the L5–S1 in the Asian adult population, and the facet joint orientation had a relationship with the CSA of the erector spinae at the L4–5.

An International Multicenter Study Assessing the Role of Ethnicity on Variation of Lumbar Facet Joint Orientation and the Occurrence of Degenerative Spondylolisthesis in Asia Pacific: A Study from the AOSpine Asia Pacific Research Collaboration Consortium.

Study Design A multinational, multiethnic, cross-sectional image-based study was performed in 33 institutions, representing 10 countries, which were part of the AOSpine Asia Pacific Research Collaboration Consortium. Objective Lumbar facet joint orientation has been reported to be associated with the development of degenerative spondylolisthesis (DS). The role of ethnicity regarding facet joint orientation remains uncertain. As such, the following study was performed across a wide-ranging population base to assess the role of ethnicity in facet joint orientation in patients with DS in the Asia Pacific region. Methods Lateral standing X-rays and axial magnetic resonance imaging scans were obtained for patients with lumbar DS. The DS parameters and facet joint angulations were assessed from L3–S1. Sex, age, body mass index (BMI), and ethnicity were also noted. Results The study included 371 patients with known ethnic origin (mean age: 62.0 years; 64% males, 36% females). The mean BMI was 25.6 kg/m2. The level of DS was most prevalent at L4–L5 (74.7%). There were 28.8% Indian, 28.6% Japanese, 18.1% Chinese, 8.6% Korean, 6.5% Thai, 4.9% Caucasian, 2.7% Filipino, and 1.9% Malay patients. Variations in facet joint angulations were noted from L3 to S1 and between patients with and without DS (p < 0.05). No differences were noted with regards to sex and overall BMI to facet joint angulations (p > 0.05); however, increasing age was found to increase the degree of angulation throughout the lumbar spine (p < 0.05). Accounting for age and the presence or absence of DS at each level, no statistically significant differences between ethnicity and degree of facet joint angulations from L3–L5 were noted (p > 0.05). Ethnic variations were noted in non-DS L5–S1 facet joint angulations, predominantly between Caucasian, Chinese, and Indian ethnicities (p < 0.05). Conclusions This study is the first to suggest that ethnicity may not play a role in facet joint orientation in the majority of cases of DS in the Asia-Pacific region. Findings from this study may facilitate future comparative studies in other multiethnic populations. An understanding of ethnic variability may assist in identifying those patients at risk of postsurgical development or progression of DS. This study also serves as a model for large-scale multicenter studies across different ethnic groups and cultural boundaries in Asia.

Lumbar Facet Joint Orientation in Degenerative Spondylolisthesis: The Role of Ethnic Variation in Asia Pacific—A Study from the AOSAP Research Collaboration

Introduction Degenerative spondylolisthesis (dSpl) can lead to various symptoms, including low back pain. Lumbar facet joint orientation has been reported to be associated with the development of dSpl. The role of ethnicity regarding facet joint orientation remains uncertain. As such, the following study was performed across a wide-ranging population base to assess the role of ethnicity in facet joint orientation in patients with dSpl in the Asia Pacific region. Materials and Methods A multinational, multiethnic cross-sectional image-based study was performed in 34 institutions in Asia Pacific, identifying 448 cases. Lateral standing X-rays and axial MRIs and/or CT scans were obtained for patients with lumbar dSpl. Magnitude of slip displacement, level of dSpl, and left/right facet joint angulation, width-curvature ratio, and gap width were noted on image assessment. Facet joint measurements were performed at each level from L3-S1. Gender, age, BMI, and ethnicity were also noted. Results The study included 389 patients with known ethnic origin (mean age: 61.4 years; 36.7% males, 63.3% females). The mean BMI was 25.6 kg/m2. The level of dSpl was most prevalent at L4/L5 (72.4%). There were 28.8% Indian, 28.5% Japanese, 17.5% Chinese, 8.2% Korean, 6.2% Thai, 4.6% Caucasian, 2.3% Filipino, 2.3% Malay, and 1.3 were of mixed Asian origin. Accounting for patient demographics and displacement, there was a statistically significant difference between ethnicity to that of left/right facet joint angulations, width-curvature ratios, and gap widths from L3-S1 between specific ethnic groups ( p &lt; 0.05). Conclusion This is the largest study to address the role of ethnicity upon lumbar facet joint orientation in dSpl. Ethnicity plays a role in facet joint orientation and may influence the occurrence and severity of dSpl or be a potential consequence. An understanding of ethnic variability may be one factor which assists in identifying those patients at risk of postsurgical development or progression of dSpl. Acknowledgments This study was funded by AOSpine Asia Pacific. Disclosure of Interest None declared

Lumbar facet joint orientation and osteoarthritis: A cross-sectional study

The association between facet orientation, tropism (asymmetry of the facet angles) and facet joint osteoarthritis (OA) has been previously reported, however, it is necessary to confirm the association in other samples. Our aim was to evaluate the association between facet orientation, tropism, and facet joint OA in an Israeli sample. One hundred and fifty low back and abdominal CTs of 82 males (mean age 61.74 ± 12.99) and 68~females (mean age 59.51 ± 11.74,) were evaluated in a cross-sectional study. Facet joint OA was evaluated at the L4-L5 spinal level using a 4-graded scale. The association between facet joint OA, facet orientation and tropism was examined using multiple logistic regressions adjusted for age and sex. Facet orientation showed a statistically significant association with facet joint OA on the right side (p=0.009) and in a model where both sides were combined (p=0.003). Facet joints with OA were more sagittally oriented. Tropism was not associated with facet joint OA on either side (p=0.251 for right and 0.609 for the left side), or in a combination of both sides (p=0.482). We confirm a significant association between sagittal orientation and OA of the lumbar facet joints at level L4-L5. Facet tropism was not associated with facet joint OA. Additional longitudinal studies are needed to understand the causal relationship between facet joint orientation and OA.

Orientation and Osteoarthritis of Lumbar Facet Joints: Association with Degenerative Disk Disease

Introduction Several studies have shown relationship between sagittal orientation of lumbar facet joint and degenerative spondylolisthesis1,2,3; however, there is no current information on how much the facet orientation and osteoarthritis associate with different grades and morphologies of lumbar disk degeneration on MRI. We hypothesize that sagittally oriented facet joints promote a degenerated intervertebral disk (IVD) to develop spondylolisthesis rather than a collapsed disk. Aim of this study is to evaluate the association between lumbar facet joint orientation, facet osteoarthritis, IVD herniation, and different grades of disk degeneration. Materials and Methods A total of 550 patients who underwent lumbar spine MRI for low back pain or radicular leg pain were reviewed. Patients with previous back surgery, congenital anomalies, spondylolysis, infection, tumor, or fracture were excluded. Total 153 patients were included and assessed for IVD degeneration according to Modified Pfirrmann (MP) grading4 at L3-S1 lumbar segments. Facet joint angles on axial scan and Fujiwara osteoarthritic grading5 were assessed at spinal segments of the following six groups: “Bright disk” (MP grade 1 or 2), “Black disk” (MP grade 4 or 5), “Collapse disk” (MP grade 6 to 8), “Herniated disk” (bulging or prolpase), spondylolisthesis and “nonslip level” of spondylolisthesis. The mean facet angles and the percentages of the mild (Fujiwara grade 1 or 2) and advanced (Fujiwara grade 3 or 4) facet osteoarthritis were compared between six groups using independent sample t test and Pearson Chi Square test, respectively. The association of facet joint orientation and osteoarthritis was also examined by linear regression analysis. Results The mean facet angles relative to the coronal plane in patients who had “Black disk” (right L3/4: 55.70, L4/5: 47.50, L5/S1: 39.70), “Collapse disk” (right L3/4: 54.10, L4/5: 470, L5/S1: 380) and “Herniated disk” (right L3/4: 560, L4/5: 46.10, L5/S1: 38.10) were significantly more sagittal at all levels (p0, L4/5: 41.10, L5/S1: 35.80). There was no statistical difference of mean facet angles at all levels between “Black disk”, “Collapse disk,” and “Herniated disk” (Table 1). Facet joint osteoarthritis were more advanced in “Black disk”, “Collapse disk”, “Herniated disk” than “Bright disk”, but there was no difference in percentage of mild and advanced facet osteoarthritis among three groups. Degenerative spondylolisthesis segments demonstrated significantly more sagittal mean facet angle (right L3/4: 72.60, L4/5: 67.20, L5/S1: 490, p0, L4/5: 540, L5/S1: 420, p0, which is the mean facet angle of patient without spondylolisthesis + SD, was 25 times more likely to have degenerative spondylolisthesis. Advanced degenerative “Collapse disk” had no significant difference in mean facet angle from that of early degenerative “Black disk.” A positive association between sagittal orientation and osteoarthritis of facet joints was demonstrated. Only degenerative spondylolisthesis demonstrated the significant correlation between facet joint osteoarthritis and disk degeneration (Fig. 1). Conclusion Sagittal facet orientation relates to facet joint osteoarthritis and IVD degeneration. Degenerative spondylolisthesis had more advanced facet osteoarthrosis and disk degeneration. The increase in facet angles at “nonslip” levels other than that of the spondylolisthesis suggests that increased facet angles represent variations in developmental anatomy and contribute to instability of a functional spine unit when degenerative disk loses its anterior vertebral column support. I confirm having declared any potential conflict of interest for all authors listed on this abstract No Disclosure of Interest None declared Kalichman, et al. Facet orientation and tropism associations with facet joint osteoarthritis and degeneratives. Spine 2009; 34(16):E579-E585 Boden, et al. Orientation of the lumbar facet joints: association with degenerative disc disease. Journal of Joint and Bone surgery 1996;78A(3):403–411 Fujiwara, et al. Orientation and osteoarthritis of the lumbar facet joint. CORR 2001;385:88–94 Griffith, et al. Modified Pfirrmann grading system for lumbar intervertebral disc degeneration. Spine 2007; 32(24):708–712 Fujiwara, et al. The relationship between facet joint osteoarthritis and disc degeneration of the lumbar spine: an MRI study. European Spine Journal 1999; 8:396–401

Age-Related Changes in the Orientation of Lumbar Facet Joints

A measurement and analysis of the orientation of the lumbar facet joints at the L4-L5 level of different age groups. To explore the correlation between age and orientation of the lumbar facet joints. Previous studies have shown an association between sagittal orientation of the lumbar facet joints and degenerative spondylolisthesis, however, there is no information available on the association between orientation of the lumbar facet joints and age. This article studied the association between orientation of the lumbar facet joints and age. Three hundred spinal disease-free people coming for periodic physical examination during May 2007 and 2008 in our hospital accepted lumbar computed tomography (CT) scanning and were randomly selected. All the subjects were divided into 6 groups based on age (group I: <30 years of age, group II: 31-40 years, group III: 41-50 years, group IV: 51-60 years, group V: 61-70 years, and group VI: >70 years of age). CT scans of the lumbar spine were stored in digitized form for measurement and analysis. The orientation of the lumbar facet joints at the L4-L5 was measured on axial CT scans, and the intersection angle of the midsagittal line of vertebra to the facet line represent the orientation of the facet joint. The angles of the L4-L5 facet joints to the vertebral sagittal plane of group I to VI are 50.61 degrees +/- 6.55 degrees, 47.05 degrees +/- 7.53 degrees, 46.56 degrees +/- 7.38 degrees, 43.39 degrees +/- 6.19 degrees, 40.95 degrees +/- 7.27 degrees, and 39.89 degrees +/- 9.05 degrees, respectively (P = 0.000). The coronal orientation of the L4-L5 facet joints was negatively correlated to age (r = -0.456, P = 0.000), which could be one of the explanations that the aging people are prone to degenerative spondylolisthesis.

Reviewer’s comment to “Functional MRI of the spine: different patterns of positions of the forward flexed lumbar spine in healthy subjects” by Alexander König and Hans-Ekkehart Vitzthum

lumbar spine flexion by means of a new type of magnetic resonance imaging (MRI) system, the authors open new perspectives in functional radiological studies of the spine without exposure to ionising radiation. Although measurement error due to drawing lines along vertebral endplates and positioning in a rather narrow gantry opening might have played an unknown role, the findings, if reproducible, are interesting as they establish significant relationships between lumbar facet joint orientation and patterns of lumbar spine flexion motion. This interesting paper highlights the fact that, besides constituting a welcome alternative to classical functional X-ray studies, MRI is also able to include the muscular apparatus in the picture. In the past, although they have recognised the importance of the muscular apparatus, spine surgeons have had to focus mainly on the osseo-ligamentous system, as the muscular apparatus was not able to be visualised. With MRI allowing studies of muscles, and possibly also functional studies, this might change in the future. REVIEWER’S COMMENT Eur Spine J (2001) 10 :443 DOI 10.1007/s005860000242

The facet orientation circle. A new parameter for facet joint angulation in the lower lumbar spine.

A descriptive quantitative evaluation was done of the transverse orientation of the lower lumbar facet joints as measured by computed tomography scanning. To evaluate a new parameter for facet joint angulation in the transverse plane (the "facet orientation circle") and to obtain reference values for this new parameter. In other studies, both in vitro and in vivo, the angulation of the facet joints has been measured in degrees relative to the frontal or sagittal plane. These methods have some limitations. The parameter used in the present study has not been described in the literature. Lower lumbar facet joint orientation was measured in 212 vertebral levels of 123 consecutive patients using the facet orientation circle parameter. Patients with degenerative or developmental abnormalities of the lumbar spine were excluded, as were those with technically inadequate computed tomography studies. Mean facet orientation circle diameters (+/-SD) were: L3-L4, 43.7 +/- 10.5 mm; L4-L5, 63.8 +/- 26.4 mm; and L5-S1, 82.3 +/- 23.5 mm. Differences between right and left sides were: L3-L4, 6.3 +/- 7.1 mm; L4-L5, 13.9 +/- 25.3 mm; and L5-S1, 17.9 +/- 16.2 mm, intra-observer variability was 2.3%. Measurement of facet joint angulation using the facet orientation circle is possible and reproducible. The morphometric data presented may be useful as a reference for biomechanical and clinical research of facet joint orientation and asymmetry.

The Value of Computerized Tomography in Determining Lumbar Facet Joint Orientation

The reliability of assessing facet joint obliquity from standard CT scans in the lumbar spine was studied. There was no significant difference in repeated measurements by one single examiner, nor in measurements made by different examiners. Measurement of facet joint obliquity from CT scans made on different occasions was not significantly different either. This reproducibility occurred despite the fact that adjacent CT scans from one joint extremity to the other showed variation in obliquity of about 11%.

DISORDERS OF VOLUNTARY MUSCLE

<h3>ABSTRACT</h3> <h3>Background:</h3> A spinal motion segment comprises facet joints and intervertebral disc. A complex interplay of biomechanical factors occurs between them with degeneration giving rise to numerous pathological conditions. We conducted a study to find a correlation between facet joint orientation and intervertebral discs with age. <h3>Methods:</h3> A cross-sectional study of 203 consecutive subjects undergoing a computed tomography scan of abdomen and pelvis were included. Subjects were divided into 5 groups based on age (group I: 18–30 years; group II: 31–40 years; group III: 41–50 years; group IV: 51–60 years; group V: 61–70 years). Using 3-dimensional reconstruction images, orientation of lumbar facet joints at the L4-5 level was measured. Similarly, adjacent disc heights at L3-4 and L4-5 were measured and their ratio was documented. <h3>Results:</h3> The study included 106 males and 97 females. A positive correlation was noted between age and sagittal facet orientation until age 60 years. However, after age 60 years, a negative correlation with age was seen, which was statistically significant. Similarly, the disc height ratios show a progressive decline in their values with age. However, this decline was statistically significant only after age 60 years. <h3>Conclusion:</h3> The gradual change of facet joint orientation from sagittal to coronal as the age crosses from 30 to 60, to beyond 60, with a simultaneous and parallel diminishing in the disc height probably is one of the attributes of the phenomenon of autostabilization of a motion segment.