The influence of facet tropism on herniation of the lumbar disc in adolescents and adults

Facet Joint Morphology and Tropism in Adolescents: Association With Lumbar Disk Herniation and Spondylolysis

STUDY DESIGN

A cross-sectional and observational study.

OBJECTIVE

To investigate the incidence of bidirectional lumbar facet tropism and its relationship with lumbar spine disease in adolescents.

SUMMARY OF BACKGROUND DATA

There is limited information on facet joint asymmetry in the sagittal plane in adolescents.

MATERIALS AND METHODS

The orientation of all lumbar facet joints was measured in the bidirectional planes on computed tomographic images for 191 patients with low back pain. The patients were divided into 4 groups according to age (<15 or ≥15 yr) and sex. The facet joint angle and tropism rate were compared among the groups. Facet tropism was defined as a difference in bilateral angle of >10° in the axial plane and >5° in the sagittal plane. Facet joint orientation was compared among groups using a one-way analysis of variance and Tukey honestly significant difference test or Games-Howell post hoc test and the incidence of facet tropism using the Kruskal-Wallis test with Bonferroni correction. The association of facet tropism with disease was investigated further by analyzing facet joint orientation and the incidence of facet tropism in 116 patients with single-level lumbar disease.

RESULTS

Facet tropism was observed in 8.7% of axial views and 7.5% of sagittal views. The incidence of axial facet tropism was significantly higher in male patients aged ≥15 years, especially at L4/5. Facet joint morphology in the axial plane was more coronal at L3/4 and L4/5 in male patients ≥15 years than in those <15 years. Facet joint morphology in the sagittal plane was unchanged at around 15 years of age in both sexes. Axial facet tropism was found at L4/5 in 55.6% of patients with herniated nucleus pulposus. There was a significant difference in sagittal facet orientation in patients with spondylolysis at L5. The facet angle was significantly larger in patients with L5 spondylolysis at L3/4 and L4/5.

CONCLUSIONS

Facet tropism in adolescents is similar in the axial and sagittal planes. Facet tropism and specific morphology may be related to lumbar disk herniation and spondylolysis in this age group.

Patient-related risk factors and lifestyle factors for lumbar degenerative disc disease: a systematic review

OBJECTIVE

Back pain is a very widespread disease pattern and is one of the most frequent causes for consultation of a physician in general. In most cases, discogenic changes are the pathomorphological correlate of back pain. Numerous risk factors have been identified for these degenerative changes, but the influence and significance of the risk factors remain unclear, which was the aim of this systematic review.

METHODS

A systematic literature search of the commonly used Pubmed database was performed using specific MESH terms. Further selection of the included studies was performed according to the PRISMA scheme, taking into account scientific merit as well as the relation to the research question.

RESULTS

A total of 111 studies out of 1035 found were finally included in the literature search. 134 risk factors for disc degeneration and disc herniation were identified. These were divided into (1) patient-specific risk factors (n░=░34), (2) radiological risk factors (n░=░31), (3) lifestyle risk factors (n░=░6), (4) workplace-related risk factors (n░=░12), (5) genetic risk factors (n░=░50), and (6) other risk factors (n░=░1). Non-adjustable risk factors were age >50 years (OR 1.7/year), female gender (OR 1.41), family disposition (OR 4.0), comorbidities like atherosclerosis (OR 2.24), arthritic changes in other joints (OR 3.1) and history of injuries of the back (OR 3.1). Adjustable factors were elevated BMI (OR 2.77), comorbidities like hypertension (OR 1.25), dyslipidemia (OR 1.26) and diabetes mellitus (OR 6.8), as well as lifestyle habits like smoking (OR 3.8).

DISCUSSION

In summary, intervertebral disc degenerations and herniations represent multifactorial events whose risk factors can be partly influenced and partly not influenced. This systematic review highlights the current state of knowledge as a basis for creating patient-specific algorithms to calculate risk for the development or progression of degenerative disc changes and disc herniations.

Are there correlations between facet joint parameters and lumbar disk herniation laterality in young adults?

OBJECTIVE

We aimed to determine whether there is an association, in young adults, between the occurrence of lumbar disk herniation (LDH) at a given segment and the segment's facet joint parameters [facet orientation (FO) and tropism (FT)]. In addition, associations between facet joint parameters in the corresponding segment and LDH laterality were also investigated.

METHODS

We retrospectively analyzed data from 529 patients who were between 18 and 35 years old, who had experienced single-level LDH (L4-5 or L5-S1) between June 2017 and December 2019, and with<2 years of clinical history. We included an additional 122 patients with no history of LDH as an age-matched control group. LDH were classified by laterality (left-sided, right-sided, or central herniation). At each level, we investigated the relationship between facet joint parameters and herniation laterality.

RESULTS

FO_A values at the L4-L5 level and the L5-S1 level were significantly lower and FT was higher for the LDH group compared with those for the control group. The level at which LDH occurred, FO_L, FO_R, and FT differed significantly among the three groups. There was a significant association between herniationlaterality and FO at the L4-L5 level but not at the L5-S1 level.

CONCLUSIONS

Abnormal facet joint parameters are significantly associated with LDH. Young adults with higher FT should be paid more attention, to prevent the occurrence of LDH. Compared with L5-S1 level, intervertebral disk herniation at the L4-L5 level tended to occur ipsilateral to the side with a lower facet joint angle when FT was present.

Evaluation the association of facet tropism in multi-sports athletes with cervical disc hernia

Background

Facet tropism (FT) can be defined as the angular difference between the orientation of the right and left facet joints in axial or sagittal planes. Most studies discuss about the relationship with lumbar disc hernia and facet joint angle. However, little is known about the association of facet tropism with disc herniation in the cervical spine in multisports athletes. In this study, We aimed to investigate the relationship between cervical facet tropism and disc hernia in athletes of different branches between the ages of 20–40 from the cervical MR images of the cases.

Methods

This is a retrospective study performed on athletes who applied our hospital between January 2014–2019 with neck pain and have MR imaging of the cervical spine. Cervical MR images of the patients were evaluated by an experienced radiologist from the hospital system database and archives. 79 cases (52 men and 27 women) were included in the study.

Results

No statistically significant difference was found between the facet joint angles of both groups at all levels (p˃0.05). Only left C6-7 disc angles of CDH group were measured as 92.99° ± 10.77⁰ (62⁰–113⁰) and 88.58° ± 7.65° (67°-110°) for the normal group and this difference was found statistically significant (p = 0.007).

Conclusion

In this study, we did not predict that cervical facet tropism may be a factor associated with cervical disc hernia in young athletes with CDH.

Facet Tropism/Inclination and Its Association with Intervertebral Disc Herniation in the Lumbar Spine - A Radiological Evaluation

Objective  To assess the role of facet tropism (FT) in intervertebral disc prolapse. Methods  A total 98 patients with lower back pain were included in the study. Magnetic resonance imaging scans were performed and analyzed. The angles of the right and left facets were measured on the axial section. Patients without disc prolapse at the L3-L4, L4-L5 and L5-S1 levels act as controls for those with disc prolapse at the same levels. A statistical analysis was also performed. Results  The incidence of FT at the L3-L4 level was of 85.2% in patients with disc herniation ( n  = 27), and of 56.3% in the control group, which was statistically significant ( p  = 0.008). Similarly, at the L4-L5 level, incidence of FT among cases and controls was of 71.4% ( n  = 35) and 52.4% respectively ( p  = 0.066). At the L5-S1 the incidence was of 66% and 51% among cases and controls respectively ( p  = 0.13). Conclusion  We found a positive association between FT and disc herniation at the L3-L4 level, but no association at the L4-L5 and L5-S1 levels.

Facet tropism: Association between cervical disc degeneration and cervical spondylotic radiculopathy in middle-aged patients

This study aimed to retrospectively explore the relationship between facet tropism (FT) and cervical disc degeneration in cervical spondylotic radiculopathy (CSR) patients on 3-dimensional views. A total of 180 middle-aged patients with single-level CSR at C4/5 who underwent cervical CT and MRI in our hospital were included. The incidence of FT (or called FT (+), defined as FT ≥ 7 degree) at C3/4, C4/5, C5/6 levels were measured and calculated by reconstructed CT images on 3-dimensional views. The grade of cervical disc degeneration at three levels was assessed by MRI images by the method of Miyazali. Univariate analysis was performed to compare their cervical disc degeneration grade and CSR incidence between two groups stratified by FT (+). Moreover, a logistic regression model was used to investigate the association between FT (+) and grade of cervical disc degeneration and incidence of CSR adjusting for age, gender, and BMI. Grade of cervical disc degeneration and incidence of CSR in axial FT (+) group were both significantly increased compared to axial FT (-) group, while sagittal and coronal FT (+) groups showed no difference. Axial FT (+) was significantly associated with the grade of cervical disc degeneration and incidence of CSR. in middle-aged patients with CSR, axial FT (+) might be the risk factor for cervical disc degeneration but not sagittal and coronal FT (+). Also, axial FT (+) was positively associated with CSR incidence. Therefore, axial FT might play a vital role in the progression of cervical disc degeneration and CSR occurrence.

A Systematic Review and Meta-Analysis of the Facet Joint Orientation and Its Effect on the Lumbar

Facet tropism is recognized as the difference in the positioning of the facet joints in association with each other in the sagittal plane. This guides to an imbalanced biomechanical force over the facet joints and the intervertebral disc during rotation and other physiological activities. A systematic review and meta-analysis of Web of Science, EMBASE, PubMed, Cochrane Library, SCOPUS, and CINHAL from 2004 to 2021 to recognize the related research studies was performed. The data for meta-analysis were obtained from multiple studies to get the combined effect of the facet tropism on the lumbar disc herniation (LDH) and the degenerative lumbar spondylolisthesis (LDS). 117 articles were incorporated in the systematic review, where 41 studies were selected for meta-analysis, out of which 7 studies were found eligible as per the inclusion criteria. When degenerative lumbar spondylolisthesis was compared with the normal group, 95% CI was observed at 1.94 (1.59, 2.28). There was a comparison of disc herniation with the normal group in L4/L5, with a 95% CI of 0.60 (0.05, 1.14). The L5/S1 disc herniation was compared with the normal group and was found to be 0.21 (-0.48, 0.90). Therefore, it was observed that facet tropism is related to lumbar disc herniation and degenerative lumbar spondylolisthesis. Our meta-analysis demonstrated a unique link between the facet tropism and the lumbar disk degeneration along with degenerative lumbar spondylolisthesis.

The effects of vertebral rotation on the position of the aorta relative to the spine in patients with adult degenerative scoliosis

Aims

This study aimed to explore the effects of vertebral rotation on the position of the aorta relative to the thracolumbar and lumbar spine, and to identify risk factors for vertebral rotation in patients with adult degenerative scoliosis (ADS).

Methods

A total of 71 patients with ADS were divided into left scoliosis (LS) group (n = 40 cases) and right scoliosis (RS) group (n = 31cases) with well-matched demographics. Apical vertebrae, Cobb angle (°), coronal horizontal movement, thoracolumbar kyphosis (TLK) and Nash-Moe rotation classification were measured on X-ray. The Cartesian coordinate system was established on T2-MRI for each level of intervertebral disc on thracolumbar and lumbar spine, where aorta-vertebrae angle (α), aorta-vertebrae distance (d), and vertebral rotation angle (γ) for each level of T12-L1 to L3-L4 on MRI were defined within the Cartesian coordinate system.

Results

There was no statistical difference in the distribution of apical vertebrae between LS and RS groups. Nash-Moe classification was of no significance between the two groups. When there was a larger Cobb angle and coronal horizontal movement, a greater γ in LS group and a lower γ in RS group were noted (both p < 0.001). There was no correlation among γ, α, and d in LS group (p = 0.908 and 0.661, respectively) nor in RS group (p = 0.738 and 0.289, respectively). In LS group, Nash-Moe classification correlated to Cobb angle, coronal movement and TLK. In RS group, it correlated to Cobb angle and coronal movement. Cobb angle was the risk factor for Nash-Moe classification in RS group while no factors were identified in LS group. Coronal movement was independent risk factor for γ (p = 0.003) in LS group. Moreover, γ was affected by Cobb angle (p = 0.001) and coronal horizontal movement (p = 0.006) in RS group.

Conclusion

Vertebral rotation could be predicted by Cobb angle or coronal horizontal movement measured on X-ray in ADS patients and aorta maintained in a relatively normal position in patients with ADS.

The Correlation Between Facet Tropism and Intervertebral Disc Herniation in the Subaxial Cervical Spine

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

Investigating the correlation between the facet tropism (FT) and subaxial cervical disc herniation (CDH).

SUMMARY OF BACKGROUND DATA

Although debatable, it was widely reported that FT was associated with lumbar disc herniation. However, the exact correlation between FT and subaxial CDH is still unclear.

METHODS

Two-hundred patients with any disc herniation at C3/4, C4/5, C5/6, or C6/7 and 50 normal participants without CDH (normal control group) were included in this study. For patients, the cervical levels with CDH and the levels without herniation were classified into the "herniation group" and "patient control group," respectively. Bilateral facet joint angles at C3/4, C4/5, C5/6, and C6/7 on sagittal, axial, and coronal planes were measured on computed tomography (CT). The disc degeneration at each level was assessed on magnetic resonance imaging (MRI).

RESULTS

Both the mean difference between left and right facet angles and tropism incidence in herniation group were significantly greater than those in two control groups whenever at C3/4, C4/5, C5/6, or C6/7 level and whenever on sagittal, axial, or coronal plane. The mean differences of angles and tropism incidences in most patient control groups were not significantly greater than those of corresponding normal control groups. The incidence of greater facet angle at the left or right side was not significantly different among the left, central, and right herniation groups. The mean disc degeneration grades in both herniation and patient control groups were significantly higher than those in normal control groups while no difference between herniation and patient control groups.

CONCLUSION

The FT on the sagittal, axial, and coronal planes are all associated with CDH in the subaxial cervical spine. The greater facet angle at the left or right side does not affect the side of herniation. The severity of cervical disc degeneration is not associated with FT.Level of Evidence: 3.

Facet Tropism in Lumbar Spine and Cervical Spine: A Systematic Review and Meta-Analysis

BACKGROUND

Facet tropism (FT) refers to the difference in the orientation of facet joints with respect to each other in the sagittal plane. FT leads to unequal biomechanical forces on facet joint and intervertebral disc during rotation and other physiologic movements. Most of the studies have reported the incidence of FT in the lumbar spine to vary between 40% and 70%, with L4-5 level being the most commonly afflicted level. The objective of this study was to find the association between FT and various lumbar and cervical degenerative disorders.

METHODS

A systematic search of PubMed was performed with the keywords "facet tropism" and "facet asymmetry." Data for meta-analysis were extracted from the studies to obtain pooled impact of FT on lumbar disc herniation (LDH) and lumbar degenerative spondylolisthesis (LDS).

RESULTS

Eighty-two articles were included in the systematic review and 18 studies had the required data to be included in the meta-analysis. The pooled standard mean difference between FT angles in patients with or without LDH was 0.31 with (P = 0.04). The pooled odds ratio for FT in patients with LDH was 3.27 with (P = 0.02). Subgroup analysis showed that there is no significant difference in the L3/4, L4/5, and L5S1 subgroups. The pooled standard mean difference between FT angles in patients with or without LDS was 0.54 (P = 0.009).

CONCLUSIONS

FT is significantly associated with LDH and LDS along with various other lumbar and cervical degenerative diseases.

FACET JOINT DEGENERATION IN PATIENTS WITH LUMBAR DISC HERNIATION AND PROBABLE DETERMINING FACTORS

ABSTRACT Objective To evaluate facet joint degeneration following surgical treatment in patients with lumbar disc herniation, seeking to correlate it with possible determining factors. Methods Cross-sectional observational study, which analyzed medical records, radiographs and magnetic resonance images of 287 patients with lumbar disc herniation treated surgically at the Spine Surgery Service of the Hospital Ortopédico de Passo Fundo. Information about age and sex was collected. In the imaging exams, the following variables were evaluated: facet joint angulation and its tropism, measured by the Karacan method, sacral slope and lumbar lordosis, measured by the Cobb method, arthrosis of the interfacetary joints, measured by the Weishaupt classification, and intervertebral disc degeneration, measured by the Pfirrmann classification. Results A statistically significant relationship was observed between facet joint degeneration and age (p = 0.002), and also between facet joint degeneration and sacral slope (p = 0.038). No correlation was found between facet joint degeneration and lumbar lordosis (p = 0.934). It was found that the most degenerated facet joints were those that had the greatest facet joint asymmetry (tropism). However, the mean degree of facet tropism did not increase homogeneously with the progression of the joint degeneration score (p = 0.380). Conclusion It was verified that there are, in fact, a multiplicity of factors related to the degree of facet joint degeneration in the low lumbar spine. Additional studies, correlated with the asymmetry of the facet joints, would be important to elucidate better preventive management of this degeneration, aiming to avert secondary low back pain and sciatica with advancing age. Level of evidence II; Retrospective study.

Lumbar Facet Tropism on Different Facet Portions and Asymmetry Between Ipsilateral Cephalad and Caudad Portions: Their Correlations With L4/5 and L5/S1 Lumbar Disc Herniation

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

To investigate the correlation between lumbar disc herniation (LDH) and lumbar facet tropism (FT) on cephalad and caudad facet portions, respectively; to investigate the asymmetry between ipsilateral cephalad and caudad facet portions and its correlation with LDH.

SUMMARY OF BACKGROUND DATA

There are still heavy debates on the exact correlation between lumbar FT and LDH. However, no study ever focused on the FT on different facet portions and asymmetry between ipsilateral cephalad and caudad portions in patients with LDH.

METHODS

One hundred patients with L4/5 LDH, 100 patients with L5/S1 LDH, and 100 participants without LDH (control group) were age and sex matched and included in this study. Participants in each group were further divided into two subgroups based on age (≥ or < 50 yr old). Bilateral facet joint angles on both cephalad and caudad portions were measured. FT and asymmetry between ipsilateral cephalad and caudad portions in each LDH group were compared with those in corresponding control group.

RESULTS

Comparing with control participants, the mean difference of bilateral facet angles in older patients with L4/5 LDH was significantly greater either on cephalad portion and caudad portion, whereas significantly higher frequency of FT was only exhibited on cephalad portion. In older patients with L4/5 LDH, the mean difference of facet angle between ipsilateral cephalad and caudad portions was significantly greater than that of control participants, the frequency of ipsilateral cephalad, and caudad facet asymmetry was also significantly higher.

CONCLUSIONS

Only the FT on cephalad portion but not caudad portion of facet joint is associated with L4/5 LDH of older patients. The measurement on different portions of facet joint may result in discrepancy on FT identification. Asymmetry between ipsilateral cephalad and caudad facet portions is also associated with L4/5 LDH in older patients.

LEVEL OF EVIDENCE

3.

Facet Tropism and Orientation: Risk Factors for Degenerative Lumbar Spinal Stenosis

The aim of this study is to establish whether facet tropism (FT) and orientation (FO) are associated with degenerative lumbar spinal stenosis (DLSS). A retrospective computerized tomography (CT) study including 274 individuals was divided into two groups: control (82 males and 81 females) and stenosis (59 males and 52 females). All participants have undergone high-resolution CT scan of the lumbar spine in the same position. FT and FO were measured at L1-2 to L5-S1. Significant sagittal FO was noted in the stenosis males (L2-3 to L4-5) and females (L2-3 to L5-S1) compared to the controls. The prevalence of FT was remarkably greater in the stenosis males (L4-5, L5-S1) and females (L3-4, L5-S1) compared to their counterparts in the control group. Our results also showed that FT (L3-4 to L5-S1) increases approximately 2.9 times the likelihood for DLSS development. This study indicates that FO and FT in the lower lumbar spine are significantly associated with DLSS.

Facet joint parameters which may act as risk factors for chronic low back pain

BACKGROUND

Facet orientation (FO) and facet tropism (FT) are two important structural parameters of lumbar facet joint. The purpose of this study was to evaluate the association between facet joint parameters and chronic low back pain (LBP).

METHODS

From June 2017 to January 2019, a total of 542 cases were enrolled in this study. There were 237 males and 305 females with a mean age of 35.8 years (range 18~59 years). All the cases were divided into a LBP group (LBP group) and a non-LBP group (N-LBP group) in this study. We compared their clinical parameters and facet joint parameters between two groups.

RESULTS

The LBP group was composed of 190 male and 252 female, whose ages ranged from 17 to 59 years (35.6 ±7.9 y). The N- LBP group was composed of 47 male and 53 female, whose ages ranged from 18 to 59 years (35.9 ± 7.5 y). Of these parameters, BMI (P = 0.008) and FT (P = 0.003) at all three levels were found to be significantly associated with incidence of chronic LBP (P < 0.05), but FO were only found to be significant at L3-L4 level and L5-S1 level (P < 0.05). Logistic regression analysis showed that high BMI and large FT were significant risk factors for chronic LBP (P < 0.05), and FT were found to might be independent risk factors for chronic LBP.

CONCLUSION

FT may play a more important role in the pathogenesis of chronic LBP.

Does facet tropism negatively affect the response to transforaminal epidural steroid injections? A prospective clinical study

OBJECTIVE

To examine the impact of the presence of facet tropism on the results of transforaminal epidural steroid injection for unilateral radicular pain induced by lumbar disc herniation.

MATERIALS AND METHODS

We included 112 patients diagnosed with unilateral, single-level lumbar disc herniation-induced radicular pain. Injection was planned at relevant levels. The patients were assessed using the Numerical Rating Scale, the Modified Oswestry Disability Index, and the Beck Depression Inventory before the injection and at hour 1, week 3, and month 3 after the injection. Presence of facet tropism was assessed by measuring the facet angles in the L3-4, L4-5, and L5-S1 segments of lumbar MRI T2 sequence axial section.

RESULTS

A significant decrease in the Numerical Rating Scale and an increase in the Modified Oswestry Disability Index scores were detected at all follow-ups in groups comprising 39 patients with and 61 without facet tropism (p < 0.05). On comparison, improvement in clinical parameters at week 3 and month 3 in the group without facet tropism was greater (p < 0.05). As treatment success is considered to be a ≥ 50% reduction in the Numerical Rating Scale scores, 55.2% of the patients attained treatment success at month 3. Further, although the treatment success rate in the group with facet tropism was 34.2%, it was 69% in that without facet tropism (p < 0.05).

CONCLUSION

Facet tropism correlates with less success of transforaminal epidural steroid injection; therefore, facet tropism may be a worthwhile measurement in a discussion with patients of the benefits of the procedure.

The Relationship of Facet Joint Orientation and Tropism with Lumbar Disc Herniation and Degenerative Spondylolisthesis in the Lower Lumbar Spine

STUDY DESIGN

Retrospective study.

PURPOSE

This study aimed to clarify the relationship of both facet tropism (FT) and the sagittally aligned facet (SAF) joint with lumbar disc herniation (LDH) and degenerative spondylolisthesis (DS).

OVERVIEW OF LITERATURE

Despite several studies conducted, there is no consensus on the association of the SAF joint and FT with DH and DS.

METHODS

Between June 2015 and December 2017, magnetic resonance imaging scans of 250 consecutive patients who underwent surgery for LDH and DS were analyzed. The facet angles at all the lower lumbar levels were calculated, and SAF and FT were noted. The relationship between the side of disc herniation and that of the SAF joint were also determined. Statistical analysis was performed, and the relation of SAF and FT to LDH and DS was noted.

RESULTS

We observed a positive relationship between SAF and LDH at L4-5 and L5-S1 with a p-value of 0.02 (<0.05). FT demonstrated a positive association with LDH at L4-5 (p=0.047) but not at L3-4 or L5-S1. SAF demonstrated a positive relationship with DS at L3-4 (p<0.001) but not at L3-4 or L5-S1. FT demonstrated a significant relation with DS at L4-5 (p<0.001), whereas no positive association was observed at L3-4 and L5-S1.

CONCLUSIONS

The L4-5 level demonstrated a significant association with SAF and FT in LDH and DS. Moreover, SAF at L5-S1 demonstrated a positive association with LDH. These findings provide useful information for future longitudinal studies to elucidate the possible causes for such phenomena.

Clinical Characteristics and Risk Factors of Recurrent Lumbar Disk Herniation: A Retrospective Analysis of Three Hundred Twenty-One Cases

STUDY DESIGN

Retrospective clinical series.

OBJECTIVE

To investigate the clinical features and the risk factors for recurrent lumbar disc herniation (rLDH) in China.

SUMMARY OF BACKGROUND DATA

rLDH is a common cause of poor outcomes after lumbar microdiscectomy surgery. Risk factors for rLDH are increasingly being investigated. However, results in these previous studies were not always consistent.

METHODS

Between June 2005 and July 2012, 321 consecutive patients with single-level LDH, who underwent surgery, were enrolled in this study. We divided the patients into the recurrent group (R group) and the nonrecurrent group (N group) and compared their clinical parameters and preoperative radiologic parameters. The relationships between the variables and rLDH were evaluated by univariate analysis and multiple logistic regression analysis.

RESULTS

There was significant difference between groups in sex (P = 0.003), age (P = 0.003), current smoking (P = 0.004), body mass index (BMI) (P = 0.04), occupational lifting (P < 0.001), trauma history (P = 0.04), procedures (P = 0.04), herniation type (P = 0.006), disc height index (DUI) (P = 0.04), facet orientation (FO) (P = 0.04), facet tropism (FT) (P = 0.04), and sagittal range of motion (from) (P = 0.04). By putting these differences in logistic regression analysis, it showed that being male, young age, current smoking, higher BMI, herniation type (transligamentous extrusion), surgical procedures (bilateral laminectomy or total laminectomy), heavy works, undergoing a traumatic event, a large from, a high DUI, a large FT, and a small FO significantly related with rLDH.

CONCLUSION

Based on our data, sex, age, current smoking, BMI, occupational lifting, trauma, surgical procedures, herniation type, DUI, FO, FT, and from showed a significant correlation with the incidence of rLDH. Patients with these risk factors should be paid more attention for prevention of recurrence after primary surgery.

LEVEL OF EVIDENCE

3.

Is Facet Tropism Associated with Increased Risk of Disc Herniation in the Lumbar Spine?

STUDY DESIGN

Retrospective case control study.

PURPOSE

In current study, we compared the incidence of facet tropism (FT) in patients with lumbar disc herniation and normal controls.

OVERVIEW OF LITERATURE

It has been suggested that FT can be associated with increased risk of lumbar disc herniation.

METHODS

A total of 66 and 63 patients with L4/L5 and L5/S1 disc herniation, respectively, were evaluated in the present study. The control group comprised 61 normal subjects. Facet joint angle was measured using axial magnetic resonance images. The FT was defined as a difference of >10° between the right and left facet joints. The incidence of FT was compared between patients and controls. We also investigated the relationship between facet orientation (sagittal or coronal) and side of disc herniation.

RESULTS

The incidence of FT at the L4/L5 level was significantly higher in patients with disc herniation (48.5% vs. 26.2%, p =0.01), while it was found to be the same at the L5/S1 level in patients and controls (50.8% vs. 36%, p =0.098). Among the 64 patients with FT, intervertebral disc herniation occurred significantly toward the more sagittally oriented facet joint in 41 patients (p <0.05).

CONCLUSIONS

FT is associated with increased risk of L4/L5 intervertebral disc herniation, but not at the L5/S1 level. In addition, disc herniation occurred toward the more sagittally oriented facet joint.

A Study of Lumbar Disc Herniation and Facet Joint Asymmetry

Purpose:

To investigate the association of facet joint asymmetry with lumbar disc herniation at the lower lumbar spine.

Methods:

A total of 90 patients (ages 18–40 years) with single-level disc herniation (L3–L4, L4–L5, or L5–S1) were included in the study. Facet asymmetry was defined as a difference of 10° in facet joint angles between right and left sides. Normal discs in the same segment of other individuals were used as a control. Patients had facet asymmetry measured for L3 to S1 through 3.0T magnetic resonance imaging, and information was collected, including age, sex, degenerative degree of lumbar facet joints, and the presence or absence of lumbar disc herniation and type.

Results:

At the L3 to L4 level, 2 cases had facet asymmetry in 8 patients with lumbar disc herniation, compared with 17 cases of facet asymmetry in 82 patients without disc herniation (P = 0.7776, r = 0.030). At the L4 to L5 level, there were 21 cases of facet asymmetry in 45 patients with lumbar disc herniation, compared with 5 cases of asymmetry in 45 patients without disc herniation (P = 0.00019, r = 0.392). At the L5 to S1 level, there were 25 cases of facet asymmetry in 37 patients with lumbar disc herniation, compared with 11 cases of facet asymmetry in 53 patients without disc herniation (P = 0.0000, r = 0.492). There were 23 cases of facet asymmetry in 28 disc herniations of side type compared with 2 cases of facet asymmetry in 9 herniations of center type (P = 0.0008, r = 0.364). There was no significant difference in the relationship between age, facet joint degeneration, and lumbar facet joint asymmetry (P &gt; 0.05).

Conclusion:

Facet asymmetry is significantly associated with lumbar disc herniation at the L4 to L5 and the L5 to S1 levels, whereas there is an obvious association with the side type of lumbar disc herniation at the L5 to S1 level.

INFLUENCE OF FACET TROPISM ON THE LOCATION OF LUMBAR DISC HERNIATION

ABSTRACT Objective: To correlate facet tropism with the side and location of the intervertebral disc in which the lumbar disc herniation occurred. Methods: A retrospective descriptive study that evaluated Magnetic Resonance Imaging of 255 patients with lumbar disc herniation undergoing surgical treatment with the Spine Group of the Hospital Ortopédico de Passo Fundo between 2002 and 2014. The total patient number was stratified according to the side affected by the herniated disc (right or left), location of the hernia in the intervertebral disc (central, centrolateral, foraminal and extraforaminal) and demographic data, such as age, gender etc. The degree of facet joint tropism was measured by the Karakan method and classified as mild (difference less than 7º); moderate (between 7º and 15º) and severe (difference greater than 15º). Results: A statistical significant relationship (p= 0.023) was observed between the facet joint tropism and the side where the lumbar disc herniation occurred. No correlation was found between facet joint tropism and location of the herniation on the intervertebral disc. Conclusions: The degree of facet tropism presents a statistical significant correlation with the side of the intervertebral disc in which the lumbar disc herniation will develop. Level of Evidence: II. Type of study: Retrospective study.

Comparison of angle, shape, and position of articular processes in Dobermans and Great Danes with and without cervical spondylomyelopathy

Background

Cervical spondylomyelopathy (CSM), also known as wobbler syndrome, affects mainly large and giant-breed dogs, causing compression of the cervical spinal cord and/or nerve roots. Structural and dynamic components seem to play a role in the development of CSM; however, pathogenesis is not yet fully understood. Physiologic and pathologic movements of the cervical spine depend on the morphology and morphometry of articular processes, as well as on intervertebral discs and vertebral column ligaments. Moreover, the characteristics of the articular processes affect motion and stability of the vertebral column. The goal of this study was to investigate the angle, shape, and position of the articular surfaces within the articular processes and compare them between Doberman Pinschers and Great Danes with and without cervical spondylomyelopathy.

Results

Magnetic resonance images were obtained for 60 dogs: 15 clinically normal Dobermans (Dob-N), 15 CSM-affected Dobermans (Dob-CSM), 15 clinically normal Great Danes (GD-N), and 15 CSM-affected Great Danes (GD-CSM). Angle, shape, and position (lateral distance) of the articular surfaces from the articular processes were analyzed from C_2–3 to C₇-T₁. Results indicate that the mean angle was different between Dob-CSM and GD-CSM at C_4–5, C_5–6, and C_6–7, and between GD-N and GD-CSM at C_6–7. There were differences between Dob-N and GD-N, and between Dob-CSM and GD-CSM for the lateral distance at most locations, except C_2–3. Compared with Great Danes, Dobermans generally had a greater proportion of concave caudal surfaces at C_4–5, C_5–6, and C_6–7. Concave articular surfaces have been associated with greater axial rotation. This may explain the high proportion of disc-associated CSM in Dobermans compared to Great Danes. The differences between breeds suggest they may have different motion patterns in the caudal cervical vertebral column.

Conclusions

Considering that no differences in angle, shape, or position of the articular surfaces within the articular processes were found between normal and CSM-affected dogs, their relevance appears to have a secondary role in the pathogenesis of CSM.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-017-0997-4) contains supplementary material, which is available to authorized users.

Facet tropism: possible role in the pathology of lumbar disc herniation in adolescents

OBJECTIVE The role of facet tropism (FT) in lumbar disc herniation (LDH) is ambiguous. The present study aimed to investigate the association between FT and LDH in adolescents. METHODS This study included 65 adolescents with LDH with 1- or 2-level LDH, or both. Facet angles were measured with MRI. FT was defined as asymmetry of 10° between the left and right side. The same levels of 30 healthy persons who had no lumbar lesions were used as controls. Statistical analysis was performed using the chi-square test. RESULTS FT was identified in 16 of 39 patients with LDH in L4-5 and in 3 of 30 controls (p = 0.006, OR 6.261, 95% CI 1.619-24.217). It was also identified in 12 of 27 patients with LDH in L5-S1 and in 4 of 30 controls (p = 0.017, OR 5.200, 95% CI 1.420-19.039). One patient had LDH in both L4-5 and L5-S1. CONCLUSIONS FT is associated with LDH in both L4-5 and L5-S1 levels in adolescents.

Biomechanical analysis of press-extension technique on degenerative lumbar with disc herniation and staggered facet joint

This study investigates the effect of a new Chinese massage technique named “press-extension” on degenerative lumbar with disc herniation and facet joint dislocation, and provides a biomechanical explanation of this massage technique. Self-developed biomechanical software was used to establish a normal L1–S1 lumbar 3D FE model, which integrated the spine CT and MRI data-based anatomical structure. Then graphic technique is utilized to build a degenerative lumbar FE model with disc herniation and facet joint dislocation. According to the actual press-extension experiments, mechanic parameters are collected to set boundary condition for FE analysis. The result demonstrated that press-extension techniques bring the annuli fibrosi obvious induction effect, making the central nucleus pulposus forward close, increasing the pressure in front part. Study concludes that finite element modelling for lumbar spine is suitable for the analysis of press-extension technique impact on lumbar intervertebral disc biomechanics, to provide the basis for the disease mechanism of intervertebral disc herniation using press-extension technique.

Orientation of the facet joints in degenerative rotatory lumbar scoliosis: an MR study on 52 patients

BACKGROUND

Because of a degenerative component, degenerative rotatory scoliosis seems different from congenital and idiopathic subtypes of the disease. This study aims to examine the orientation of facet joints, as a known cause of degeneration, in patients with degenerative rotatory scoliosis.

METHODS

Lumbar magnetic resonance (MR) images and plain radiographs of 52 symptomatic patients (mean age, 50.17 years) with degenerative rotatory lumbar scoliosis (mean curve, 19.22 degrees) and 50 healthy individuals were reviewed. Facet joint angles in rotated segments and the minimum neural foramen width at all lumbar levels were measured by three observers and the average was recorded.

RESULTS

The maximum vertebral rotation was most frequent at L4-L5 (75 %), and the majority was of type I (84.6 %) according to the Nash-Moe classification. At all lumbar spinal levels the mean facet joint angles were significantly higher on the side of rotation (L2-L3, 57.92 degrees; L3-L4, 45.00 degrees; L4-L5, 43.88 degrees) compared to those on the contralateral side (L2-L3, 20.42 degrees; L3-L4, 15.48 degrees; L4-L5, 13.12 degrees) and in controls (L2-L3, 30.21 degrees; L3-L4, 40.81 degrees; L4-L5, 45.20 degrees) (p < 0.001 for all comparisons). The mean facet joint angle increased significantly from L4-L5 to L2-L3 in cases and reversely in controls. The mean minimum neural foramen width was 1.29 ± 0.85 mm on the side of rotation, 5.50 ± 1.09 mm on the contralateral side, and 6.78 ± 1.75 mm in controls (p < 0.001).

CONCLUSIONS

Substantial asymmetries and abnormal orientations in facet joints were documented in patients with degenerative rotatory lumbar scoliosis. Such asymmetries may adversely affect neural foramen width.

Irregular Alteration of Facet Orientation in Lumbar Segments: Possible Role in Pathology of Lumbar Disc Herniation in Adolescents

BACKGROUND

The role of the overall structural feature of facet joint in the development of lumbar disc herniation (LDH) is unclear. The present study aimed to investigate the role of irregular alteration of facet orientation (IAFO) in low lumbar segments in the pathology of LDH in adolescents.

METHODS

Sixty-five adolescents with LDH were included in the study. Facet angles were measured in magnetic resonance imaging. The IAFO was defined as the irregular orientation of the included facet joints angle, which was regularly increased from L3 to S1 in the normal group, including small-large-small (SLS) type, large-small-large (LSL) type, and large-small-smaller (LSS) type. Thirty normal adolescents without lumbar lesions were selected into the control group. Statistical analysis was performed using χ(2) test.

RESULTS

IAFO was observed in 20 of 65 subjects in LDH group compared with 3 of 30 in the control group [P = 0.038; OR=4 (1.086, 14.735)]. The SLS type was observed in 14 patients, and the LSL type was found in 6 patients, compared with 2 and 1, respectively, in the control group, no LSS type was found in the two groups. There were 8 subjects with IAFO of SLS style herniated in L5/S1 level compared with 6 subjects in L4/5. There was 1subject with IAFO of LSL style herniated in L5/S1 level compared with 5 subjects in L4/5.

CONCLUSIONS

The findings of this study suggest that the IAFO in the lumbar spine was associated with lumbar disc herniation in adolescents.

Evidence for juvenile disc herniation in a homo erectus boy skeleton

STUDY DESIGN

An analysis and differential diagnosis of bony alterations in the lower lumbar vertebrae of a Homo erectus boy skeleton.

OBJECTIVE

To analyze low back problems during early human evolution.

SUMMARY OF BACKGROUND DATA

Back problems in modern humans are often attributed to our upright, bipedal locomotion that is thought to place huge mechanical stresses on the vertebral column. However, little is known of this situation during the course of human evolution.

METHODS

We analyzed the lower lumbar spine of the most complete early hominid skeleton, the 1.5-million-year-old Homo erectus boy KNM-WT 15000 from Nariokotome, Kenya, who died at an age of approximately 8 years. We use bony alterations as indirect evidence for disc disease in the absence of soft tissue.

RESULTS

We describe an extensive osteophytic anterior curved remodeling of the left superior articular process of L5 and formation of a new joint at the underside of the left pedicle of L4. This indicates collisional facet joint subluxation, most likely as the result of juvenile traumatic disc herniation.

CONCLUSIONS

This indirect evidence of possible juvenile disc herniation in a Homo erectus boy skeleton represents the earliest known case of this typical human ailment that is intricately linked to upright bipedalism. The extensive bony remodeling of the articular processes of L4 and L5 suggests that the disc herniation occurred several months before his death. Disabling backache and recurrent sciatica might have, at least, temporarily restricted his daily activities, which indicates advanced social care and nursing in early Homo. We hypothesize that the early Homo intervertebral discs were more vulnerable to injury compared with modern humans because of a relatively small vertebral cross-sectional area.

Associação entre tropismo facetário e doença degenerativa de disco lombar

OBJETIVO: Documentar a presença de degeneração de disco e tropismo facetário em pacientes portadores de dor lombar crônica e sua distribuição por sexo e faixa etária. Avaliar também a associação de tropismo facetário e degeneração discal lombar além de avaliar a orientação das facetas de acordo com sexo e faixa etária. MÉTODOS: Estudo retrospectivo de imagens de ressonância magnética obtidas em 288 pacientes (N = 288; 118 homens e 170 mulheres) com média de idade de 53,33 anos, portadores de dor lombar crônica. As imagens foram avaliadas por dois médicos assistentes especialistas em cirurgia da coluna para avaliar e quantificar a orientação das facetas, o tropismo facetário e o grau de degeneração discal dos níveis L3-L4, L4-L5 e L5-S1. Foi analisada a associação entre tropismo facetário e doença degenerativa discal, além de associação com sexo e idade. RESULTADOS: Observa-se que 85,8% dos discos apresentam classificação de Pfirrmann superior ou igual ao Tipo III. Com relação ao grau de degeneração discal, não houve diferença entre os sexos e aumentou com o aumento da faixa etária. Com relação ao grau de tropismo, não difere entre os níveis avaliados e o sexo, aumenta de acordo com a elevação da faixa etária. Houve aumento do grau do degeneração discal com o aumento do grau de tropismo facetário. CONCLUSÃO: A maioria dos discos intervertebrais analisados de pacientes com dor lombar crônica encontram-se degenerados e grau de degeneração aumenta com a idade. O grau de tropismo facetário aumenta com a idade e se relaciona com o grau de degeneração discal.

Association of facet tropism with lumbar disc herniation

PURPOSE

Facet tropism is defined as asymmetry between left and right facet joints and is postulated as a possible cause of disc herniation. In the present study, the authors used a 3-T MRI to investigate the association between facet tropism and lumbar disc herniation at a particular motion segment. They also examined whether the disc herniated towards the side of the more coronally oriented facet joint.

METHODS

Sixty patients (18-40 years) with single level disc herniation (L3-L4, L4-L5, or L5-S1) were included in the study. Facet angles were measured using MRI of 3-T using the method described by Karacan et al. Facet tropism was defined as difference of 10° in facet joint angles between right and left sides. Normal disc adjacent to the herniated level was used as control. We also examined if disc herniated towards the side of more coronally oriented facet.

RESULTS

Twenty-five herniations were at L4-L5 level and 35 at L5-S1. Statistical analysis was performed using the Fischer Exact Test. At L4-L5 level, 6/25 cases had tropism compared to 3/35 controls (p = 0.145). At L5-S1 level, 13/35 cases had tropism as compared to 1/21 controls (p = 0.0094). Of 19 cases having tropism, the disc had herniated towards the coronally oriented facet in six (p = 0.11).

CONCLUSION

The findings of the study suggest that facet tropism is associated with lumbar disc herniation at the L5-S1 motion segment but not at the L4-L5 level.

Laterality of cervical disc herniation

PURPOSE

Cervical disc herniation (CDH) is found more frequently at the lower cervical spine than at the upper or middle level. However, there is scarcity of data about the laterality of CDH. The aim of this study is to detect the laterality of CDH.

METHODS

We retrospectively evaluated preoperative computed tomography myelograms and magnetic resonance images of 75 cases of CDH who underwent single level anterior cervical discectomy and fusion at C4-5, C5-6, or C6-7 levels from 2008 to 2010 in our institute. Statistical analyses were performed using the Chi-square test.

RESULTS

Eleven cases were found at C4-5 level, 42 cases at C5-6 level, and 22 cases at C6-7 level. At C4-5 level, CDH was recognized at the right side in 2 cases, at the left side in 2 cases, and at the center in 7 cases. At C5-6 level, CDH was found at the right side in 20 cases and at the left side in 22 cases. At C6-7 level, CDH was found at the right side in 3 cases and at the left side in 19 cases with significantly high frequency of left-sided CDH (p < 0.025).

CONCLUSIONS

In this study, it was revealed that the left-sided CDH was more frequent than the right-sided CDH at C6-7 level.

Intervertebral disc degeneration: evidence for two distinct phenotypes

We review the evidence that there are two types of disc degeneration. 'Endplate-driven' disc degeneration involves endplate defects and inwards collapse of the annulus, has a high heritability, mostly affects discs in the upper lumbar and thoracic spine, often starts to develop before age 30 years, usually leads to moderate back pain, and is associated with compressive injuries such as a fall on the buttocks. 'Annulus-driven' disc degeneration involves a radial fissure and/or a disc prolapse, has a low heritability, mostly affects discs in the lower lumbar spine, develops progressively after age 30 years, usually leads to severe back pain and sciatica, and is associated with repetitive bending and lifting. The structural defects which initiate the two processes both act to decompress the disc nucleus, making it less likely that the other defect could occur subsequently, and in this sense the two disc degeneration phenotypes can be viewed as distinct.

Unilateral spondylolysis and the presence of facet joint tropism

STUDY DESIGN

Retrospective review of the CT scans performed in a group of patients examined for a possible spondylolysis.

OBJECTIVE

To investigate whether there is an association between unilateral spondylolysis and facet joint tropism.

SUMMARY OF BACKGROUND DATA

Spondylolysis is a fatigue fracture of the pars interarticularis of great importance in sports injury. The demonstration of a unilateral spondylolysis is important because there is a potential for full healing if the athletic activity is modified, whereas bilateral spondylolysis frequently leads to established nonunion. Coronally orientated facet joints are known to predispose to spondylolysis by increasing the point loading of the pars interarticularis. The importance of this finding has not been investigated in unilateral spondylolysis.

METHODS

A review of patients with low back pain and a possible diagnosis of spondylolysis who were investigated with multislice CT was performed. The coronal orientation of the facet joints at L4/5 and L5/S1 was measured and comparison was done between those with and without a spondylolysis.

RESULTS

The coronal angle of 140 facet joints in 35 patients was recorded. Of 35 patients, 23 had a spondylolysis which was unilateral in 12 patients. The facet joint angle was significantly more coronally orientated in the presence of a spondylolysis when compared with an intact pars (means, 53° and 43°, respectively; P < 0.01). In the presence of a unilateral spondylolysis, the facet joint was significantly more coronally orientated on the side of the spondylolysis (means, 52° and 45°, respectively; P < 0.01). CONCLUSION.: This study is the first investigation of facet joint anatomy in unilateral spondylolysis. Asymmetric facet joints do increase the force through one side of the spine, with a unilateral spondylolysis occurring on the side of the more coronally orientated facet joint.

Analysis of the relationship between facet joint angle orientation and lumbar spine canal diameter with respect to the kinematics of the lumbar spinal unit

STUDY DESIGN

Retrospective cross-sectional study.

OBJECTIVE

This study aimed to elucidate the relationship among facet orientation, kinematics of a spinal unit, and change in lumbar spine canal diameter by using kinetic magnetic resonance imaging.

SUMMARY OF BACKGROUND DATA

Some studies have suggested an association between increased sagittally oriented facet angles and degenerative lumbar spondylolisthesis. However, no study has specifically addressed the association of facet orientation with the kinematics of a spinal unit and change in canal diameter.

METHODS

Kinetic magnetic resonance imagings were performed with patients in flexion, neutral, and extension positions. Study subjects were classified into 6 groups-AA, BB, CC, AB (BA), BC (CB), and AC (CA)-on the basis of bilateral facet angles (A, narrow; B, normal; and C, wide) and disc and facet joint degeneration. A magnetic resonance imaging analyzer was used for anatomic measurements and for calculating changes in canal diameters and disc bulging as well as the lumbar spine kinematics.

RESULTS

Osseous canal diameters were significantly smaller in the group AA than in the group BB, whereas they were significantly larger in the group CC than in the group BB. Canal diameter at the disc level was significantly smaller in the group AA than in the group BB in all 3 positions, whereas it was significantly larger in the group CC than in the group BB. Translational motion was significantly more in the group AA than in the group BB, whereas it was significantly lesser in the group CC than in the group BB.

CONCLUSIONS

We demonstrated the relationship among facet orientation, osseous canal diameter, kinematics of a spinal unit, and change in lumbar spine canal diameter. Patients with sagittally oriented facets had narrow osseous canals with mobility, whereas those with coronally oriented facets had stable and wider osseous canals. This finding is helpful in understanding the mechanism underlying lumbar spinal canal stenosis and degenerative spondylolisthesis.

Relationship of facet tropism with degeneration and stability of functional spinal unit

PURPOSE

The authors investigated the effect of lumbar facet tropism (FT) on intervertebral disc degeneration (DD), facet joint degeneration (FJD), and segmental translational motion.

MATERIALS AND METHODS

Using kinetic MRI (KMRI), lumbar FT, which was defined as a difference in symmetry of more than 7 degrees between the orientations of the facet joints, was investigated in 900 functional spinal units (300 subjects) in flexion, neutral, and extension postures. Each segment at L3-L4, L4-L5, and L5-S1 was assessed based on the extent of DD (grade I-V) and FJD (grade 1-4). According to the presence of FT, they were classified into two groups; one with FT and one with facet symmetry. For each group, demographics, DD, FJD and translational segmental motion were compared.

RESULTS

The incidence of FT was 34.5% at L3-L4, 35.1% at L4-L5, and 35.2% at L5-S1. Age and gender did not show any significant relationship with FT. Additionally, no correlation was observed between DD and FT. FT, however, was found to be associated with a higher incidence of highly degenerated facet joints at L4-L5 when compared to patients without FT (p < 0.01). Finally, FT was not observed to have any effects upon translational segmental motion.

CONCLUSION

No significant correlation was observed between lumbar FT and DD or translational segmental motion. However, FT was shown to be associated significantly with the presence of high grades of FJD at L4-L5. This suggests that at active sites of segmental motion, FT may predispose to the development of facet joint degeneration.