Ligamentum Flavum Thickness Research Articles

Factors Associated with Thickening of the Ligamentum Flavum on Magnetic Resonance Imaging in Patients with Lumbar Spinal Canal Stenosis.

Experimental study of the ligamentum flavum (LF) thickness among patients with lumbar spinal canal stenosis (LSCS). To elucidate the factors associated with thickening of the LF on magnetic resonance imaging (MRI). Thickening of the LF is a major contributor to LSCS. This thickening is attributed to tissue hypertrophy or buckling of the ligament, and there may be several associated factors on MRI; however, these factors remain unclear. We studied the LF in 56 patients (a total of 106 ligaments) with LSCS, who underwent decompressive surgery; among them, 23 were receiving haemodialysis. The Pearson correlation coefficient was used to assess relationships between the thickness of the LF on MRI and the thickness of the LF tissue, age, disc height, disc degeneration, and disc level. Patients were also categorised into 2 groups based on whether they were undergoing haemodialysis, and the relationships were assessed similarly. Among patients with LSCS, the thickness of the LF on MRI showed a significant positive linear relationship with the thickness of the LF tissue, and no association with disc height. Except for in those receiving haemodialysis, the thickness of the LF on MRI showed a significant positive relationship with age, disc degeneration, and disc level among patients with LSCS. In patients with LSCS, thickening of the LF on MRI appears to represent tissue hypertrophy. The association between the thickness of the LF on MRI and age, disc degeneration, and disc level may indicate simultaneous alterations of spine components along with aging that was cancelled by the effects of haemodialysis.

Epidural caudal steroid injection in low backache and lumbar radiculopathy at tertiary care centre

Most of the lumbosacral radiculopathies are caused by irritation of spinal nerve roots associated with lower back and leg pain. Most common causes for spinal root irritation are intervertebral disc herniation and spinal canal stenosis, other causes include spondylolisthesis, spondylosis, thickening of ligamentum flavum, scoliosis etc. Lumbar radiculopathy frequently treated by epidural corticosteroid injections. Common route for administering epidural steroid injections are interlaminar, transforaminal and caudal. But there are concerns due to rare major neurologic complications after this treatment. Therefore this literature focuses on caudal route of epidural steroid injections. To know the benefits of caudal epidural steroid injection in lumbar radiculopathy and low backache by analyzing clinical and functional outcome.Out of 35 patients, in 28 patients (80%) low backache and radiating pain subsided after 3 days. But 7 patients (20%) get partial relief or having persistent complaints after 3 days, administered 2epidural steroid injection after a month. After one month 32 patients (91%) do not complain of pain but 3 patients (9%) tend to have some back pain which eventually improved on two to three months of regular physiotherapy and postural correction exercises.Caudal epidural steroid injections are safe, quick and effective. It can be performed on OPD basis, has considerably fewer side effects than surgery. Therefore injections can help to increase function while avoiding surgery and long term use of analgesics.

Human lumbosacral root and ligamentum flavum thicknesses: a magnetic resonance study.

This study investigated the lumbosacral plexus (LSP) nerve root thickness and ligamentum flavum (LF) thickness and correlated them with age and sex. These findings provided a useful data for spinal nerve root micro-anastomosis surgery and lumbar decompression surgery. This retrospective study was conducted with 350 individuals with ages ranging from 21 to 80 years under magnetic resonance imaging to evaluate the possible cause of a lower back pain. According to the morphometric measurements of the LSP root thickness, the diameter gradually increased from L1 to S1. L1 has the thinnest root (3.9 ± 0.81 mm) while S1 has the thickest root (5.45 ± 0.8 mm). The measurements revealed inconsiderable differences in the LSP thickness in relation to age, sex in the study population. Regarding the LF, the thickness of the LF was found to insignificantly increase with age. Besides, the LF thickness was inconsequentially higher in female. The mean thickness of the right LF at different spinal levels was measured (L2-L3 = 3.19 ± 0.27, L3-L4 = 3.38 ± 0.11 mm, L4-L5 = 3.71 ± 0.29 mm, and L5-S1 = 3.64 ± 0.21 mm). The mean thickness of the left LF was non-significantly higher. The LSP root and LF thicknesses not related to age or sex.

P40. Indirect effect on adjacent segment after minimally invasive transforaminal lumbar interbody fusion

<h3>BACKGROUND CONTEXT</h3> MIS-TLIF is an alternative treatment for degenerative spine disease, which aims to decompress and stabilize the most stenotic level correlating with clinical symptoms, while sparing the less severe adjacent segments. According to previous studies, interbody fusion was reported to not only affect the fused level, but also the adjacent segments. These effects might cause changes in canal dimensions at the adjacent segments, leading to unsatisfactory postoperative symptoms. <h3>PURPOSE</h3> The goal of this study was to compare the dural sac area and other canal dimension parameters on MRI at the adjacent segments before and after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), including the change in segmental and regional parameters measured on plain radiograph. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study King Chulalongkorn Memorial Hospital. <h3>PATIENT SAMPLE</h3> Patients who underwent MIS-TLIF at L4/5 level in King Chulalongkorn Memorial Hospital The indications for surgery were spinal canal stenosis, herniated nucleus pulposus, and spondylolisthesis grade 1-2. <h3>OUTCOME MEASURES</h3> MR image parameters: dural sac area (DSA), sagittal spinal AP diameter (SAPD), ligamentum flavum area (LFA), ligamentum flavum thickness (LFT), foraminal area (FA), foraminal height (FH), at the adjacent segments of fused level. Standing lateral plain radiograph: disc height (DH), segmental angle (SA) of adjacent segments and fused level lumbar lordosis (LL) <h3>METHODS</h3> Forty-four patients who underwent MIS-TLIF at L4/5 level were examined. The indications for surgery were spinal canal stenosis, herniated nucleus pulposus, and spondylolisthesis grade 1-2. We reviewed their standing plain radiograph and MR image parameters, including dural sac area (DSA), sagittal spinal AP diameter (SAPD), ligamentum flavum area (LFA), ligamentum flavum thickness (LFT), foraminal area (FA), foraminal height (FH), disc height (DH), segmental angle (SA), and lumbar lordosis (LL) at the adjacent segments of fused level. Disc height and segmental angle at fused level was also reviewed. All parameters were compared before, and 3 months postoperatively. <h3>RESULTS</h3> The mean (SD) pre- and postoperative DSA at upper adjacent segment was 125.12 (35.72) and 133.17 (35.07) mm2, while pre- and postoperative DSA at lower adjacent segment was 103.58 (44.32) and 117.66 (46.34) mm2 respectively. The postoperative DSA significantly increased in the upper (mean change 8.05 (95%CI 4.44-11.66) mm2, P <0.001) and lower (14.08 (95%CI 9.47 – 18.69) mm2; P <0.001) adjacent segments. Eleven (25%) and 22 (25%) patients had preoperative upper adjacent segment areas <100 mm2 and ≥100 mm2respectively. The mean change in DSA was greater in patients with preoperative DSA <100 mm2 versus ≥100 mm2, but the difference was more pronounced in the upper versus the lower adjacent segment (4.3 (95%CI -4 to 12.7) mm2; P = 0.30 versus 1.1 (95%CI -8.3 to 10.4); P = 0.82, respectively). Significant increases in SAPD were also seen in both upper (0.85 (95%CI 0.45 to 1.25 mm; P <0.001) and lower (0.66 (95%CI 0.34 to 0.97) mm; P<0.001) adjacent segments. LFT significantly decreased in the lower adjacent segment (-0.37 (95%CI -0.62 to -0.11) mm; P=0.006); a small but non-significant decrease was also observed in the upper adjacent segment (-0.1 (95%CI -0.37 to 0.17) mm; P=0.47). No other significant changes in other canal dimensions were noted. <h3>CONCLUSIONS</h3> Adjacent segment DSA increased significantly after MIS-TLIF. In addition, other parameters representing canal dimension (SAPD, LFT) also significantly changed after the operation. Further studies are needed to assess the relationship between these changes and postoperative clinical outcomes. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

An Objective Assessment of Lumbar Spine Degeneration/Ageing Seen on MRI Using An Ensemble Method-A Novel Approach to Lumbar MRI Reporting.

Retrospective, randomized, radiographic study assessing age-related changes (ARCs) on lumbar magnetic resonance imaging (MRI) using an ensemble method. This study proposed to develop a novel reporting method to calculate a predicted "age estimate" for the ARC seen on lumbar MRI. Lumbar MRI reports include pathological findings but usually not the prevalence data of common findings which has been shown to decrease the need for narcotics in the management of non-specific lower back pain (NSLBP). Comparing the normal age estimation for lumbar spine degenerative changes/ARC on MRI and comparing this to the patient's real age may improve patient outcome in the management of NSLBP. A total of 60 lumbar MRI were taken from patients aged between 0 and 100 years. Lumbar MRI features reported as associated with age on review of the literature were measured on each MRI and statistically evaluated for correlation with age. Factors found to be associated were then entered into an ensemble model consisting of several machine learning techniques. The resulting ensemble model was then tested to predict age for a further 10 random lumbar MRI scans. One further lumbar MRI was then assessed for observer variability. Features that correlated with age were disc signal intensity, the appearance of paravertebral and psoas muscle, disc height, facet joint size, ligamentum flavum thickness, Schmorl nodes, Modic changes, vertebral osteophytes, and high-intensity zones. With the ensemble model, 80% of estimated spinal age were within 11 years of the subjects' physical age. It would appear that the intervertebral discs, and many other structures that are subjected to loading in and around the lumbar spine change their lumbar MRI appearance in a predictable way with increasing age. ARC on lumbar MRI can be assessed to predict an "expected age" for the subject.Level of Evidence: 2.

Sequential MRI Changes After Lateral Lumbar Interbody Fusion in Spondylolisthesis with Mild and Severe Lumbar Spinal Stenosis

We assessed the sequential magnetic resonance imaging changes of indirect neural decompression after minimally invasive lumbar lateral interbody fusion (LIF) combined with posterior percutaneous pedicle screw (PPS) fixation for degenerative spondylolisthesis (DS) according to the severity of preoperative lumbar spinal stenosis. A total of 43 patients (mean age, 68.7 years; 16 men and 27 women) with DS who had undergone LIF and closed reduction with PPS fixation were enrolled. The intervertebral levels were divided into the moderate stenosis (MS) group (preoperative cross-sectional area [CSA] of the thecal sac >50 mm2) and severe stenosis (SS) group (CSA ≤50 mm2). The CSA, ligamentum flavum thickness, and diameter of the thecal sac at the affected level were measured on cross-sectional magnetic resonance images at baseline, immediately postoperatively, and 2 years postoperatively. For the 31 and 29 intervertebral levels in the MS and SS groups, the mean CSA at baseline, immediately postoperatively, and 2 years postoperatively was 76.9 mm2 and 35.8 mm2, 104.3 mm2 and 81.4 mm2, and 130.9 mm2 and 105.7 mm2, respectively. The mean ligamentum flavum thicknesses at 2 years postoperatively became thinner than that immediately after surgery in both groups (P < 0.01). The mean diameter of the thecal sac at 2 years was longer than that immediately after surgery in both groups (MS group, P< 0.05; SS group, P < 0.01) The expansion ratio of the CSA at 2 years postoperatively was significantly greater in the SS group than that in the MS group (P < 0.01). Sequential enlargement of the spinal canal was obtained by the thinning of the ligamentum flavum after LIF and PPS fixation in patients with DS with both mild and severe stenosis. The effect of indirect neural decompression was equivalent even in those with severe lumbar spinal stenosis.

Lumbar ligamentum flavum burden: Evaluating the role of ATTRwt amyloid deposition in ligamentum flavum thickness at all lumbar levels

BackgroundWild-type transthyretin (ATTRwt) amyloid deposition has been found in the ligamentum flavum (LF) of patients undergoing spinal stenosis surgery. Our group previously reported that ATTRwt amyloid is associated with an increased lumbar ligamentum flavum thickness at symptomatic levels that required surgery. A comprehensive evaluation of LF thickness at asymptomatic levels in addition to symptomatic, treated levels has never been performed in ATTRwt patients. In this study, we compare the total LF thickness of all lumbar levels (lumbar LF burden) in ATTRwt and non-ATTRwt patients. MethodsWe retrospectively identified 177 patients who underwent lumbar spine surgery. Ligamentum flavum thickness of 885 lumbar levels was measured on T2-weighted axial MRI. Amyloid presence was confirmed through Congo red staining of specimens, and subtype of ATTRwt was confirmed using mass-spectrometry and gene sequencing. ResultsOf the 177 patients, 30 (16.9%) were found to have ATTRwt in the ligamentum flavum. One hundred and fifty ATTRwt levels and 735 non-ATTRwt levels were measured by four different reviewers, with an intraclass coefficient (ICC) of 0.79. Mean ligamentum flavum thickness was 4.64 (±1.31) mm in the ATTRwt group and 3.99 (±1.45) mm in the non-ATTRwt group (p < 0.001). The lumbar LF burden (sum of ligamentum flavum thickness at all lumbar levels) for ATTRwt patients was 23.22 (±4.48) mm, and for non-ATTRwt patients was 19.96 (±5.49) mm (p = 0.003) ConclusionThe lumbar LF burden is greater in patients with ATTRwt amyloid compared to non-ATTRwt patients. This supports prior evidence that ATTRwt amyloid deposition might be associated with increased LF thickness and lumbar stenosis. This potential association requires more research and could be an important finding, as medications have recently become available that can treat patients with ATTRwt amyloid deposition.

STUDY THE FIBROSIS AND HYPERTROPHY OF LIGAMENTUM FLAVUM IN LUMBAR SPINAL CANAL STENOSIS DUE TO LEPTIN INDUCED INFLAMMATIO

Lumbar spinal stenosis (LSS) is defined as the narrowing of the spinal canal with cord or nerve root impingement and as consequences the symptoms of radiculopathy or pseudoclaudication are developed. Hypertrophy of the ligamentum flavum (LF) is often involved in the pathogenesis of LSS, resulting in the reduction of diameter of the spinal canal and compression of the dural sac and nerve roots.Leptin's important role in various biological functions further than appetite regulation and energy metabolism.Interestingly collective evidence suggests it has a critical role in the fibrosis process in multiple organ systems, including the liver, kidney, and lung. The aim of this study was to establish a relationship between serum leptin levels and the fibrosis and hypertrophy of ligamentum flavum in lumbar spinal canal stenosis. METHOD: Our study include 100 patient with ligamentum flavum hypertrophy with lumbar canal stenosis to evaluate co-relation with increased serum leptin levels. Demographic data, clinical, radiological and laboratory investigation done to find a co-relation between increased serum leptins levels with the fibrosis and hypertrophy of ligamentum flavum in lumbar canal stenosis.RESULT:In our study,LF thickness was also measured with a T1weighted axial MRI.The mean thickness in the high vas scores (&gt; 5) group was signicantly thicker than that in the low vas (&lt; 5) group. Serum leptin values were positively correlated to LF Thickness at L4-L5 (r=0.228) and L5-S1 (r=0.198) level and the correlation was significant (p&gt;0.05). CONCLUSION: Our study has shown strong correlation between serum levels of leptin and hypertrophy of ligamentum flavum.VAS score in low VAS group (&lt; 5) as well as high VAS score group (&gt; 5) are positively correlated with serum levels of leptin

The increased motion of lumbar induces ligamentum flavum hypertrophy in a rat model

BackgroundThe purpose of this study was to establish a novel rat model for ligamentum flavum (LF) hypertrophy using increased motion of lumbar and to elucidate the etiology of (LFH).MethodsA total number of 30 male rats were used. The increased motion of lumbar was induced by surgical resection of L5/6 posterior elements (n = 15). The other rats underwent a sham operation (n = 15). After 8 weeks, all rats were taken lateral plain X-rays. The LF from L5/6 in both groups were harvested to investigate histological, immunohistological, and real-time PCR analysis.ResultsAccording to radiological results, the disc height ratio, flexion ratio, and extension ratio were larger in the rats in the experimental group than that of in the sham group. The HE staining showed that the LF thickness in the experimental group significantly increased in comparison to the sham group. The Masson trichrome staining showed that the ratio of elastic fibers to collagen fibers in experimental group was lower than that in the sham group. The protein and gene expression of TGF-β1, TNF-α, IL-1β, and Col 1 were significantly higher in the experimental group than that in the sham group.ConclusionA relatively safe, simple, and rapid rat model of LFH using increased motion of lumbar was established. The increased motion of lumbar could lead to high expression of inflammatory and fibrotic factors in LF, causing the accumulation of collagen fibers and decreasing of elastic fibers.

Radiological Assessment of the Effects of Anterior Cervical Discectomy and Fusion on Distraction of the Posterior Ligamentum Flavum in Patients with Degenerative Cervical Spines.

BackgroundThis study aimed to assess the effects of anterior cervical discectomy and fusion (ACDF) on distraction of the posterior ligamentum flavum (LF) by increasing the intervertebral disc height and positioning a graft in patients with degenerative cervical spine disease.MethodsSixty-eight patients with degenerative cervical diseases who underwent single-level ACDF were included in the analysis. The intervertebral disc height, Cobb angle, and transverse thickness of the LF were measured, and magnetic resonance imaging was performed both preoperatively and 6 weeks postoperatively on each patient. Correlation analyses were performed to evaluate the relationships between age, sex, change in intervertebral disc height, Cobb angle, and position of the intervertebral implant according to the postoperative change in LF thickness. The position of the intervertebral implant was categorized as anterior, middle, or posterior. We also evaluated radiological effects according to the implant position.ResultsThe mean intervertebral disc height increased from 5.88 mm preoperatively to 7.49 mm postoperatively. The Cobb angle was 0.88° preoperatively and 1.43° postoperatively. Age (p = 0.551), sex (p = 0.348), position of cage (p = 0.312), pre- and postoperative intervertebral disc height (p = 0.850, p = 0.900), Cobb angle (p = 0.977, p = 0.460), and LF thickness (p = 0.060, p = 1.00) were not related to changes in postoperative LF thickness. Postoperative increase in disc height was related to Cobb angle (r = 0.351, p = 0.038). No other factors were significantly related. The position of the cage was not related with the change of Cobb angle (p = 0.91), LF thickness (p = 0.31), or disc height (p = 0.54).ConclusionsChange in the intervertebral disc height and the position of the intervertebral implant after ACDF did not affect the thickness of the LF after surgery in patients with degenerative cervical spine disease.

The Relationship between Neural Foraminal Stenosis and Imaging Features of Lumbar Spine MRI in Patients Older Than 60 Years with Lumbar Radiculopathy

PurposeTo investigate the MRI features associated with neural foraminal stenosis (NFS) in patients older than 60 years with lumbar (L) radiculopathy.Materials and MethodsThis study included 133 retrospectively selected patients older than 60 years with lumbar radiculopathy who had undergone a lumbar spine MRI (from January 2018 to April 2018). For L4/L5 and L5/sacral (S)1 levels, NFS was reviewed blindly by two radiologists. Spondylolisthesis, retrolisthesis, disc height loss, disc bulging/herniation/central canal stenosis, ligamentum flavum thickening, and facet hypertrophy were evaluated separately for the NFS and non-NFS groups, and they were compared using univariate and multivariate analyses.ResultsThe univariate analysis revealed that disc height loss (p = 0.006) was associated with NFS for L4/L5. For L5/S1, both spondylolisthesis (p = 0.005) and facet hypertrophy (p = 0.006) were associated with NFS. The multivariate logistic analysis revealed that disc height loss was associated with NFS for L4/L5 [odds ratio (OR) = 4.272; 95% confidence interval (CI) 1.736–10.514]. For L5/S1, spondylolisthesis (OR = 3.696; 95% CI 1.297–10.530) and facet hypertrophy (OR = 6.468; 95% CI 1.283–32.617) were associated with NFS.ConclusionDisc height loss was associated with NFS for L4/L5 and spondylJophy were associated with NFS for L5/S1.

Increased thickness of lumbar spine ligamentum flavum in wild-type transthyretin amyloidosis

BackgroundWild-type transthyretin (ATTRwt) amyloid deposits have been found in the ligamentum flavum of patients undergoing surgery for spinal stenosis. The relationship between ATTRwt and ligamentum flavum thickness is unclear. We used pre-operative magnetic resonance imaging (MRI) to analyze ligamentum flavum thickness in lumbar spinal stenosis patients with and without ATTRwt amyloid. MethodsWe retrospectively identified 178 patients who underwent lumbar spine surgery. Ligamentum flavum thickness of 253 specimens was measured on T2-weighted axial MRI. Amyloid presence was confirmed through Congo red staining of specimens, and ATTRwt was confirmed using mass-spectrometry and gene sequencing. ResultsTwenty four of the 178 patients (13.5%) were found to have ATTRwt in the ligamentum flavum. Forty ATTRwt specimens and 213 non-ATTRwt specimens were measured. Mean ligamentum flavum thickness was 4.92 (±1.27) mm in the ATTRwt group and 4.00 (±1.21) mm in the non-ATTRwt group (p < 0.01). The ligamentum flavum was thickest at L4-L5, with a thickness of 5.15 (±1.27) mm and 4.23 (±1.29) mm in the ATTRwt and non-ATTRwt group, respectively (p = 0.007). There was a significant difference in ligamentum flavum thickness between ATTRwt and non-ATTRwt case for both patients younger than 70 years (p = 0.016) and those older than 70 years (p = 0.004). ATTRwt patients had greater ligamentum flavum thickness by 0.83 mm (95% confidence interval (CI): 0.41–1.25 mm, p < 0.001) when controlled for age and lumbar level. ConclusionPatients with ATTRwt had thicker ligamentum flavum compared to patients without ATTRwt. Further studies are needed to investigate the pathophysiology of ATTRwt in ligamentum flavum thickening.

Conus Medullaris Syndrome due to Ligamentum Flavum Thickening and Intervertebral Disc Bulging

Abstract A 72-year-old male with past medical history of common chronic illness presented to a rehabilitation clinic with a chief complaint of trouble walking and falls over 6 months. On detailed questioning, he has developed progressive bladder incontinence and unable to achieve erection. Physical exam revealed normal rectal tone and minimal bladder retention. Lumbar spine MRI shows severe spinal canal stenosis, with posterior elements impinging on the Conus Medullaris. He underwent T9-11 laminectomy. Upon follow up nearly 2-years post-operation, he is continent of bladder and able to walk with a rolling walker. The main differential diagnosis was Cauda Equina syndrome. Although both syndromes are surgical emergencies, accurate diagnosis would affect the surgical approach and outcome.

The correlation between imaging expression of P16 and S100 in hypertrophic ligamentum flavum

BackgroundLumbar spinal stenosis (LSS) is a common degenerative disease, which can lead to neurological dysfunction and requires surgical treatment. In the previous study, we used H&E staining and immunohistochemistry to qualitatively analyze the expression of S100 and P16 in the pathological process of ligamentum flavum (LF) hypertrophy in patients with LSS. To further explore the relationship between P16, S100 and LF hypertrophy in patients with LSS, we quantitatively detected S100 and P16 and their expressed products based on molecular biology techniques, and analyzed their imaging correlation.MethodsBefore posterior lumbar surgery, LF thickness was measured by Magnetic Resonance Imaging (MRI). Through the operation, we obtained the specimens of LF from 120 patients, all of whom were L4/5 LF. They were designated: simple lumbar disc herniation (LDH), single-segment spinal stenosis (SLSS), and double-segment LSS (DLSS). The detection of each side of LF was assessed. S100 and P16 and their expression products were detected by western blot and quantitative polymerase chain reaction (qPCR).ResultsThe dorsal mRNA expression of P16 in DLSS group was significantly higher than that in SLSS group. On the dorsal and dural side of LF, the expression of P16 mRNA and proteins in the LDH group was significantly lower than that in SLSS and DLSS groups. We found a correlation between the thickness of LF and the expression of P16. However, there was no significant difference in the expression of S100 mRNA and S100 protein on both sides of the ligament and among the three groups, and no significant correlation between the expression of S100 and the thickness of LF.ConclusionsP16 is involved in the process of LF hypertrophy in patients with LSS, and the imaging thickness of LF is related to the expression of P16. No obvious evidence proves that S100 may be related to the hypertrophy of LF in patients with LSS.

Magnetic Resonance Imaging Measurement of Ligamentum Flavum Thickness and its Relations with Age, Sex and Asymmetry

Magnetic Resonance Imaging Measurement of Ligamentum Flavum Thickness and its Relations with Age, Sex and Asymmetry

Indirect Decompression Effect to Central Canal and Ligamentum Flavum After Extreme Lateral Lumbar Interbody Fusion and Oblique Lumbar Interbody Fusion.

A retrospective study (level of evidence: level 4). To evaluate the radiographic outcomes after extreme lateral lumbar interbody fusion (XLIF) and oblique lateral lumbar interbody fusion (OLIF) procedures especially the effect of indirect decompression to the ligamentum flavum and to evaluate the effect of facet degeneration to the radiographic outcomes of these procedures. Indirect decompression via lateral lumbar interbody fusion provides spinal canal area expansion. However, the effect to the ligamentum flavum area and thickness at the operated spinal level is unclear. Thirty-five patients (57 lumbar levels) underwent XLIF or OLIF with percutaneous pedicle screw fixation (PPS) without direct posterior decompression were retrospectively studied. Radiographic parameters including ligamentum flavum area (LFA), ligamentum flavum thickness (LFT), cross-sectional area (CSA) of thecal sac, posterior disc height, foraminal height, cage alignment, and facet degeneration were measured on magnetic resonance image (MRI). Cage position was assessed with plain radiography. All of the radiographic parameters were significantly improved. Comparing pre- and postoperative value, mean LFA decreased from 78.9 ± 24.9 mm to 66.9 ± 26.8 mm (-14.2%; P-value < 0.00625). Mean right LFT decreased from 2.9 ± 0.9 mm to 2.3 ± 0.7 (-17.0%; P-value < 0.00625). Mean left LFT decreased from 3.3 ± 1.6 mm to 2.6 ± 0.9 mm (-17.6%; P-value < 0.00625). Mean CSA of thecal sac increased from 93.1 ± 43.0 mm to 127.3 ± 52.5 mm (50.8%; P-value < 0.00625). All radiographic outcomes were not significant difference between lumbar levels that have grade 0-1 and grade 2-3 or between grade 2 and grade 3 facet degeneration. Ligamentum flavum area and thickness were significantly reduced after lateral lumbar interbody fusion through both XLIF and OLIF. Unbuckling of the ligamentum flavum played an important role for improvement of spinal canal area after the indirect decompression. 4.

Decreasing thickness and remodeling of ligamentum flavum after oblique lumbar interbody fusion.

Ligamentum flavum is one of the structures that could compress the spinal canal. Few studies have reported atrophy of ligamentum flavum after spinal fusion. The purpose of this study was to demonstrate the reduction of ligamentum flavum size after oblique lumbar interbody fusion (OLIF) using magnetic resonance imaging (MRI). Seventeen patients who underwent OLIF without direct decompression were included. The MRI was obtained at the preoperative period, immediate postoperative period, and the follow-up period. Disc height (DH) was measured in plain radiograph. MRI measurements were spinal canal cross-sectional area (SCSA), ligamentum flavum thickness (LFT), ligamentum flavum area (LFA), and foraminal area (FA). Mean age of the patients was 68.5 ± 10.8. Mean times between postoperative MRI and follow-up MRI were 20.2 ± 11.9months. Mean disc height increased from 7.6 ± 1.6 to 11.6 ± 1.7mm at an immediate postoperative period but decreased to 10.1 ± 1.6mm during follow-up (p < 0.001). SCSA increased from 96.9 ± 54.9 to 136.0 ± 72.7mm2 and 171.4 ± 76.10mm2 during follow-up (p < 0.001). LFT decreased from 3.9 ± 1.2 to 3.2 ± 0.8mm (17.9%) and further decreased to 2.9 ± 0.7mm during follow-up (9.4%) (p < 0.001). LFA decreased from 97.4 ± 36.9 to 86.1 ± 36.9mm2 (11.6%) and further decreased to 77.2 ± 32.5mm2 during follow-up (10.3%) (p = 0.001). FA increased from 69.2 ± 26.6 to 96.1 ± 23.0mm2 and increased to 112.9 ± 23.0mm2 during follow-up (p < 0.001). OLIF could decompress the spinal canal and foraminal canal indirectly. Despite the diminishing disc height during the follow-up period, the spinal canal was further increased in size from the remodeling of the ligamentum flavum.

Degenerative lumbar scoliosis: added value of coronal images to routine lumbar MRI for nerve root compromise.

Radiating pain in degenerative scoliosis is primary indication for surgery. However, axial and sagittal MR images are limited for identifying nerve root compromise. Therefore, we aimed to assess the value of coronal images for evaluating nerve root compromise in degenerative scoliosis. Forty-six patients (mean 70 years; range 41-91 years; 8 men) with degenerative scoliosis were enrolled. Coronal images were added to routine MRI. Two radiologists independently reviewed 350 nerve roots in two MRI sets: sagittal images alone (set 1) and coronal and sagittal images combined (set 2). The following features were evaluated: interpedicular height, lateral osteophyte, asymmetric bulging disc, lateral listhesis, anterolisthesis, axial rotation angle, facet arthrosis, ligamentum flavum thickening, and pseudoarticulation. Symptomatic levels were determined by transforaminal selective nerve root block. There were 80 symptomatic and 270 asymptomatic nerve roots. The sensitivity (86%) and accuracy (93%) of set 2 were significantly higher than set 1 (53% and 87%) for radiculopathy, while specificity was similar between two sets (set 1, 97%; set 2, 95%). The AUC was significantly different between two sets (set 1, 0.853; set 2, 0.942). The negative interpedicular height difference, longer lateral osteophyte, asymmetric bulging disc, lateral listhesis, negative axial rotation angle difference, and pseudoarticulation were associated with change of grades between set 1 and set 2. Coronal images are helpful for diagnosing nerve root compromise in patients with degenerative scoliosis. • Sagittal and axial images have low sensitivity for detection of extraforaminal nerve root compromise in degenerative scoliosis. • Addition of coronal images may improve the sensitivity in nerve root compromise. • The structural changes that may contribute to nerve root compromise can also be easily assessed with coronal images.

Role of magnetic resonance imaging in the evaluation of low backache: Examining the disease spectrum

Introduction: The Spine Society of Europe defines low back pain (LBP) as the muscle tension or stiffness localized below the costal margin and above the inferior gluteal folds. LBP is a common musculoskeletal complain that can originate from ligaments, facet joints, vertebrae, paravertebral musculature, or spinal nerve roots. LBP lays a huge burden on the healthcare system. Aim: In this study, we analyze cases of LBP and conduct various studies within the framework of key domains of pain generators in LBP, namely (1) degenerative, (2) traumatic, (3) infectious, and (4) neoplastic etiologies. Materials and Methods: A total of 585 patients who underwent magnetic resonance imaging of lumbar spine/dorsolumbar spine with the complaints of LBP were selected for the study. The pathology was identified and grouped under one of the four entities mentioned above. Analytical tools were applied and the concerned inference was made for each case. Results and Conclusions:(1) Ligamentum flavum thickness has a positive correlation with age, severity of disc degeneration, facetal osteoarthritis, and sagittal orientation of facets at significance (P

Comparative study of thickness of ligamentum flavum in normal and stenosis of lumbar vertebrae in south Karnataka population – Retrospective study

Comparative study of thickness of ligamentum flavum in normal and stenosis of lumbar vertebrae in south Karnataka population – Retrospective study