Bilateral Facet Joints Research Articles

Thoracic Fracture–Dislocation with Bilateral Locked Facet Joints: An Effective Reduction Technique

Thoracic Fracture–Dislocation with Bilateral Locked Facet Joints: An Effective Reduction Technique

Finite element analysis of the biomechanical effects of anterior and posterior cervical fusion surgery for bilateral cervical dislocation

Lower cervical spine injuries often manifest as lower cervical vertebral fractures and dislocations, as well as lower cervical facet joint dislocations. Especially in cases of bilateral facet joint dislocations, it is important to rapidly and effectively relieve spinal cord and nerve root compression to prevent secondary spinal cord injury, while also providing reliable and long-lasting stability to the injured segment after surgery. Combined anterior and posterior approaches have the advantages of both pure anterior or posterior approaches, but the actual situation is complex and variable, making systematic theoretical analysis crucial. This study, with bilateral facet joint dislocation of the C6 segment and cervical spinal cord injury as the research background, established a three-dimensional model of the cervical spine C3-C7 after implementing four types of anterior-posterior combined surgeries. The four surgical approaches consist of four combinations: anterior parallel or inclined screw placement combined with posterior Margel or Anderson method screw insertion. Through finite element method, a systematic comparative analysis of the theoretical effects of the four combined surgeries in treating bilateral facet joint dislocation of the cervical spine was conducted. The conclusion was that the variations in the four combined fixation methods have a certain impact on the biomechanical characteristics of the intervertebral disc nucleus. There is a clear mutual influence relationship among anterior and posterior fixation instruments. Based on the model used in this study, it is recommended to use a torque greater than 2.1 nm to tighten the locking nut of the posterior rod to ensure reliable internal fixation.

Predictors of failure after primary anterior cervical discectomy and fusion for subaxial traumatic spine injuries

IntroductionTraumatic subaxial fractures account for more than half of all cervical spine injuries. The optimal surgical approach is a matter of debate and may include anterior, posterior or a combined anteroposterior (360º) approach. Analyzing a cohort of patients initially treated with anterior cervical discectomy and fusion (ACDF) for traumatic subaxial injuries, the study aimed to identify predictors for treatment failure and the subsequent need for supplementary posterior fusion (PF).MethodsA retrospective, single center, consecutive cohort study of all adult patients undergoing primary ACDF for traumatic subaxial cervical spine fractures between 2006 and 2018 was undertaken and 341 patients were included. Baseline clinical and radiological data for all included patients were analyzed and 11 cases of supplementary posterior fixation were identified.ResultsPatients were operated at a median of 2.0 days from the trauma, undergoing 1-level (78%), 2-levels (16%) and ≥ 3-levels (6.2%) ACDF. A delayed supplementary PF was performed in 11 cases, due to ACDF failure. On univariable regression analysis, older age (p = 0.017), shorter stature (p = 0.031), posterior longitudinal ligament (PLL) injury (p = 0.004), injury to ligamentum flavum (p = 0.005), bilateral facet joint dislocation (p < 0.001) and traumatic cervical spondylolisthesis (p = 0.003) predicted ACDF failure. On the multivariable regression model, older age (p = 0.015), PLL injury (p = 0.048), and bilateral facet joint dislocation (p = 0.010) remained as independent predictors of ACDF failure.ConclusionsACDF is safe and effective for the treatment of subaxial cervical spine fractures. High age, bilateral facet joint dislocation and traumatic PLL disruption are independent predictors of failure. We suggest increased vigilance regarding these cases.

Impact of bilateral facet joint violation on radiographic degeneration of superior adjacent segments and clinical outcomes.

Facet joint violation (FJV) is associated with postoperative low-back pain and is a confirmed risk factor for adjacent-segment degeneration, a long-term complication of lumbar fusion surgery. The authors' knowledge of its mechanisms comes from in vitro biomechanical research only; there is a lack of radiographic evidence of the effects of violation on the superior adjacent-segment facet joint, intervertebral disc, and other local radiographic parameters. Furthermore, any differences between unilateral and bilateral violation remain relatively unclear. The authors therefore aimed to explore the effects of nonviolation and unilateral and bilateral violation on radiographic degeneration of the facet joint and intervertebral disc at the fusion and superior adjacent segment. Patient-reported clinical outcomes were compared at the 2-year follow-up. The authors retrospectively analyzed data from 148 patients with lumbar degenerative diseases who underwent single-segment minimally invasive transforaminal lumbar interbody fusion between 2016 and 2020. FJV and facet joint degeneration were evaluated and graded using Shah's method and Pathria's standard, respectively. Radiographic parameters, including disc height and intervertebral Cobb angle at the fusion and superior adjacent segment, were measured. Clinical outcomes were evaluated using visual analog scale (VAS) and Japanese Orthopaedic Association scores. Preoperative data were comparable among the 3 groups (nonviolation, unilateral violation, and bilateral violation) (p > 0.05). Patient-reported clinical outcomes were followed up for at least 2 years (average duration 28.17 ± 6.17 months). At the last follow-up, facet joint degeneration grades were sequentially increased in the nonviolation, unilateral violation, and bilateral violation groups (p = 0.006). The unilateral (2.45 ± 2.17 mm) and bilateral (2.70 ± 1.94 mm) violation groups had more severe losses of disc height in the superior adjacent segment than did the nonviolation group (1.31 ± 2.01 mm). The VAS low-back pain and Japanese Orthopaedic Association scores in the bilateral (2.57 ± 1.44 and 19.83 ± 2.84, respectively) and unilateral (2.26 ± 0.79 and 20.43 ± 3.85, respectively) violation groups were significantly worse than in the nonviolation group (1.69 ± 1.12 and 21.80 ± 3.36, respectively) (p < 0.05). By contrast, there were no significant between-group differences in disc height, intervertebral Cobb angle in the fusion segment, or VAS leg pain scores (p > 0.05). FJV was associated with postoperative low-back pain and worse functional outcomes. It also aggravated facet joint and intervertebral disc changes in the superior adjacent segment, especially when bilateral violation occurred; this may be part of the mechanisms of adjacent-segment degeneration.

Supplementary posterior fusion in patients operated on employing TLIF may decrease the instrumentation failure rate.

It is supposed that additional posterior fusion may provide additional stability of the pedicle screw; however, the clinical impact of additional posterior fusion in patients treated with TLIF remains uncertain. The objective of this study is to assess the clinical efficacy of circumferential fusion in patients treated with TLIF. This is a single-center retrospective evaluation of consecutive 179 patients with degenerative lumbar stenosis and instability of spinal segments. Patients with axial pain and neurogenic claudication or radiculopathy associated with spinal stenosis were enrolled during the period from 2012 to 2018. Transforaminal lumbar interbody fusion (TLIF) with a single cage was used to treat patients. In 118 cases a supplementary posterior fusion was made. The duration of follow-up accounted for 24 months, logistic regression analysis was used to assess factors that influence the complication rate. The rate of pedicle screw loosening was growing with radiodensity getting decreased and was more frequent in patients with two level fusion. An increase in pedicle screw loosening rate correlated with anterior nonunion Tan 2 and 3 grade while both posterior complete and incomplete fusion resulted in a decline in the complication rate. Lumbosacral fusion, bilateral facet joints` resection and laminectomy turned out to be insignificant factors. The overall goodness of fit of the estimated general multivariate model was χ2 = 87.2230; P < 0.0001. To confirm clinical relevance of those findings, a univariate logistic regression was performed to assess the association between clinically significant pedicle screw instability and posterior fusion in patients operated on employing TLIF. The results of logistic regression analysis demonstrate that additional posterior fusion may decrease the rate of instrumentation failure that requires revision surgery in patients treated with TLIF [B0 = 1.314321; B1 = -3.218279; p = 0.0023; OR = 24.98507; 95% CI (3.209265; 194.5162), the overall goodness of fit of the estimated regression was χ2 = 22.29538, p = <0.0001]. Circumferential fusion in patients operated on employing TLIF is associated with a decline in the rate of pedicle screw loosening detected by CT imaging and clinically significant instrumentation failure.

SURG-27. 17-YEAR EXPERIENCE OF SURGICAL MANAGEMENT OF INTRADURAL EXTRAMEDULLARY (IDEM) TUMORS: CLINICAL OUTCOMES FROM A LOW- AND MIDDLE-INCOME COUNTRY

Abstract INTRODUCTION Surgical outcomes of intradural extramedullary (IDEM) tumors have been well-reported in the literature from high-income countries. However, limited contemporaneous data from low- and middle-income countries (LMICs) exists. This study sought to analyze the clinical outcomes of all IDEM tumor cases operated during a 17-year period at a resource-limited setting in an LMIC. METHODS The present work was conducted and reported in accordance with Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. A retrospective cohort study was carried out to analyze all IDEM tumor cases, operated upon by a consultant neurosurgeon, during 2004-2021, at a resource-limited setting in Southern India. All patients underwent routine biochemical and radiological investigations, including contrast-enhanced MRI. Laminectomy and tumor resection under the microscope were done without using intraoperative neuro-monitoring. Nerve fibers running through the tumor were sacrificed. Bilateral facet joints were preserved to ensure integrity without spinal fusion. All cases received a dural closure with 5-0 Prolene, with postoperative MRI confirming complete resection. Patients received telephonic and/or in-person follow-up visits. RESULTS 50 patients with a mean age of 46.3 years (range 13-80) were included, with 31 males and 19 females. Their clinical presentation included radiculopathy (78%), radiculomyelopathy (12%), and radiculomyelopathy with bowel and bladder symptoms (10%). Histologically, schwannomas were the most common (52%), followed by neurofibromas (34%), meningiomas (12%), and ependymomas (2%). Two individuals were diagnosed with Neurofibromatosis Type 1. All meningiomas occurred in the thoracic region, with 83.3% of cases being in females. All patients had symptomatic relief postoperatively. No major adverse events occurred, including CSF leaks, permanent neurological deficits, or spinal instability. Recurrence occurred in two 'dumbbell' tumors (4%) at 5 and 7 years after primary excision during follow-up, managed with successful re-resection. CONCLUSION Microsurgical excision of IDEM tumors carries high safety and efficacy, including in resource-limited settings like LMICs.

Activation of the Nrf-2 pathway by pinocembrin safeguards vertebral endplate chondrocytes against apoptosis and degeneration caused by oxidative stress

AimThe occurrence and progression of intervertebral disc degeneration (IDD) are significantly influenced by the cartilaginous endplate (CEP). Pinocembrin (PIN), a type of flavonoid present in propolis and botanicals, demonstrates both antioxidant and anti-inflammatory characteristics, which could potentially be utilized in management. Therefore, it is crucial to investigate how PIN protects against CEP degeneration and its mechanisms, offering valuable insights for IDD therapy. Materials and methodsTo investigate the protective impact of PIN in vivo, we created the IDD mouse model through bilateral facet joint transection. In vitro, an IDD pathological environment was mimicked by applying TBHP to treat endplate chondrocytes. Key findingsIn vivo, compared with the IDD group, the mouse in the PIN group effectively mitigates IDD progression and CEP calcification. In vitro, the activation of the Nrf-2 pathway improves the process of Parkin-mediated autophagy in mitochondria and decreases ferroptosis in chondrocytes. This enhancement promotes cell survival by addressing the imbalance of redox during pathological conditions related to IDD. Knocking down Nrf-2 with siRNA fails to provide protection to endplate chondrocytes against apoptosis and degeneration. SignificanceThe Nrf-2-mediated activation of mitochondrial autophagy and suppression of ferroptosis play a crucial role in safeguarding against oxidative stress-induced degeneration and calcification of CEP through the protective function of PIN. To sum up, this research offers detailed explanations about how PIN can protect against apoptosis and calcification in CEP, providing valuable information about the development of IDD and suggesting possible treatment approaches.

Influence of weight-bearing on the 3D movement of lumbar facet joints in the sitting position

ObjectiveTo analyze the motion characteristics of lumbar facet joints and to observe the effect of weight-bearing on lumbar facet joints in the sitting position.MethodsTen normal subjects (5 males and 5 females) were recruited and scanned by CT, and their lumbar 3D models were reconstructed by software. The images of flexion and extension of lumbar facet joints in the sitting position were collected without weight-bearing and weight-bearing 10 kg, and the 2D model was constructed by software. The 2D-3D model was matched to restore the flexion and extension motion changes of the subjects’ lumbar spine in the sitting position. Coordinates were established in the middle of the vertebral body and copied to the facet joints. Measure and record the lumbar facet joint movement distance through coordinate system. The relevant data of facet joints were collected.ResultsIn the L3/4 segment, after weight loading, the displacement of the left facet joint in the X axis became larger, while that in the Y axis and Z axis decreased. The displacement of the right facet joint in the X axis and Y axis increased, and the Z axis displacement decreased. The rotation angle of the bilateral facet joints also decreased. In the L4/5 segment, after loading, the displacements of the X, Y, and Z axis displacements of both sides increase, while the rotation angles of α and β increase, while the rotation angle of γ decreases. In the L5/S1 segment, the displacements of the X, Y, and Z axes on the left side decrease. The displacement of the X and Y axes on the right side decreases, while the displacement on the Z axis increases. The rotation angles of α and γ increase, and the rotation angle of the β axis decreases.ConclusionWhen sitting, the flexion and extension distance and rotational displacement of lumbar facet joints are not affected by weight-bearing. In addition, there is asymmetry in the movement of the left and right facet joints, and weight bearing has no effect on the asymmetry of the motion.

Visible trephine-based foraminoplasty in PTED leads to asymmetrical stress changes and instability in the surgical and adjacent segments: a finite element analysis

This study aimed to construct a multi-segment lumbar finite element model (FEM) of PTED surgery to analyze the changes in stress and ROM after visible trephine-based foraminoplasty. The CT scans of a 35-year-old healthy male were used to develop a multi-segment lumbar FEM with Mimic, Geomagic Studio, Hypermesh and MSC.Patran. Different foraminoplasty was performed on the model, and these were grouped into normal group (A), the ventral resection group (B), the apex resection group (C), the ventral + apex + isthmus resection group (D), and the SAP + isthmus + lateral recess resection group (E). A vertical load of 500N and a torque of 10N·M were applied to the upper surface of the L3 vertebral body to simulate the biomechanical characteristics under the motion of flexion, extension, lateral bending, and rotation. The von Mises stress maps of the intervertebral f, vertebral body, facet joints, and the ROM of the L3-S1 intervertebral disk were calculated and analyzed. The changes of peak stress on the vertebral body for each group were not significant in the same motion state. Significant stress differences were observed in the L4/5 intervertebral disks, while no obvious stress changes were observed for the L3/4 and L5/S1 intervertebral disks. The stress of the L3/4 and L5/S1 facet joints decreased after L4/5 foraminoplasty, while the stress of L4/5 facet joints displayed an overall increasing trend. Significant asymmetrical stress changes of bilateral facet joints were observed in all three segments, particularly during bilateral rotation movements. The ROM of L3-S1 gradually increased from Group A to Group E, especially during flexion, left lateral bending, and right rotation, with the highest elevation observed for the L45 ROM. Our FEM indicated that enlarged resection and exposure of the articular surface could lead to significant asymmetrical stress changes in the bilateral facet joints and ROM instability of the surgical and adjacent segments. These findings suggested that unnecessary and excessive resection should be avoided in PTED to reduce the incidence of low back pain and the risk of postsurgical degeneration.

Axial rotation and pain are associated with facet joint osteoarthritis in adolescent idiopathic scoliosis

Facet joints are crucial for spinal stability and develop premature osteoarthritis in patients with adolescent idiopathic scoliosis (AIS). Here, we evaluated the association between facet joint cartilage and subchondral bone homeostasis, perceived back pain and 3-dimensional spinal deformity to understand better the role of facet joint degeneration in AIS progression and pain. Cartilage and bone osteoarthritic states of AIS facet joint surgical samples were characterized using histological OARSI scoring, visual morphological grading and μCT analysis, respectively. Back pain was self-reported using a numerical rating scale and expressed relative to the location on the patient's back. The scoliotic curves from our patient cohort were digitally reconstructed using biplanar radiographs and the eOS system (EOS imaging). The deformity was then reduced to three intervertebral angles (coronal, sagittal and axial) for each pair of bilateral facet joints. Statistical associations between the intervertebral angles, osteoarthritis parameters and pain intensity were performed using the Spearman method and Friedman test. Facet joint cartilage degeneration was associated with decreased subchondral bone volume and quality. Most importantly, asymmetrical, and overall degeneration of facet joints was strongly correlated to intervertebral axial rotation. Additionally, kyphotic intervertebral segments in the sagittal plane were good predictors of increased facet joint degeneration and back pain. Facet joint degeneration is associated with axial deformity, kyphotic intervertebral angle and back pain intensity in AIS. These results suggest that facet joints are important features to consider for rotational instability in AIS spines and related disease progression and perceived back pain.

Is it feasible to treat unstable traumatic spondylolisthesis of the axis via posterior fixation without fusion?

BackgroundFew studies reported treatment of unstable traumatic spondylolisthesis of the axis using posterior fixation without fusion. The aim of this study was to evaluate the results and feasibility of posterior fixation without fusion in treating unstable traumatic spondylolisthesis of the axis.MethodsEleven patients with traumatic spondylolisthesis of the axis were included in this study, and posterior fixation without fusion using screw-rod system was performed for them. The clinical outcomes were assessed using the Visual Analog Scale (VAS), the Neck Disability Index (NDI), and the Odom’s grading system. Plain radiography was used to measure the displacement and angulation of C2-C3, and cervical lordosis. Plain radiography and computed tomography were also used to observe the bony fusions of fracture lines and postoperative spontaneous fusion of C2-C3.ResultsThe mean follow up time was 24.6 months (range, 12–72 months). The VAS and NDI scores were significantly improved at the final follow-up compared with those before operation (P < 0.05), and according to Odom’s criteria, 90.9% (10/11) of patients rated their level of satisfaction as excellent or good. The angulation and displacement of C2-C3, and cervical lordosis were significantly improved after operation compared with those before operation (P < 0.05), and at the final follow-up, and these radiological parameters were maintained. All patients achieved solid bony fusions of fracture lines. No operative segment instability was found in all patients during the follow-up period. Spontaneous fusion at bilateral C2-C3 facet joints was found in 11 cases, and anterior and/or posterior bony bridge of intervertebral bodies at C2-C3 was found in 9 cases.ConclusionsPosterior fixation without fusion may be a feasible and effective option for unstable traumatic spondylolisthesis of the axis.

The Effectiveness of Facet Joint Injection with Steroid and Botulinum Toxin in Severe Lumbar Central Spinal Stenosis: A Randomized Controlled Trial.

Lumbar central spinal stenosis (LCSS) is a common disorder that causes disability and pain in the elderly. It causes pain in the radicular leg. Recently, transforaminal epidural steroid injection (TFESI) has been widely used to control radicular leg pain caused by LCSS. However, in cases of severe LCSS, drugs injected using TFESI cannot spread into the spinal canal and would have less therapeutic effects than in mild LCSS. To compensate for this limitation of TFESI, we injected steroids and botulinum toxin type A into the bilateral facet joints, evaluated their effects, and compared them with those of TFESI. One hundred patients with severe LCSS were included in the study and randomly allocated to either the facet injection (FI) or TFESI group. For 50 patients in the FI group, 30 mg (40 mg/mL) of triamcinolone with 50 IU of botulinum toxin type A mixed with a 1 mL solution of 100 mL of 50% dextrose water and 30 mL of 4% lidocaine were administered into the bilateral facet joints under fluoroscopy. For 50 patients in the TFESI group, 30 mg (40 mg/mL) of triamcinolone with 0.8 mL of 2% lidocaine and 2.5 mL of 50% dextrose water was injected bilaterally under fluoroscopy. Radicular leg pain (measured with a numeric rating scale) and pain-related disability (measured with the modified Oswestry Disability Index) due to severe LCSS were significantly reduced after facet joint injection. The therapeutic effects were greater after facet joint injection than after bilateral TFESI. The injection of a mixed solution of steroids and botulinum toxin type A into the bilateral facet joints would be a beneficial therapeutic option in patients with severe LCSS.

Lumbar Facet Joint Effusion on Magnetic Resonance Imaging: Do Different Joint Effusion Images Have Different Clinical Values?

The objective of the study was to explore the significance of the distribution of lumbar facet joint effusion (unilateral or bilateral) and the amount of joint effusion in the process of lumbar degeneration. A total of 142 patients with L4-5 lumbar facet joint effusion in our hospital from December 2020 to December 2021 were analyzed retrospectively, including 69 cases of unilateral facet joint effusion and 73 cases of bilateral facet joint effusion. The correlation between joint effusion width, effusion area and lumbar stability, facet joint degeneration grade, lumbar intervertebral disc degeneration index, and lumbosacral angle (LSA) was analyzed. To study the significance of the distribution of joint effusion, the patients were divided into unilateral and bilateral effusion groups. The size of the LSA in the bilateral effusion group was significantly larger than that in the unilateral effusion group (t=3.6634, P<0.05). There was a significantdifference in the proportion of stability between both groups (P<0.05). The width of the joint effusion was positively correlated with lumbar stability and the LSA. When the width of the joint effusion was 2mm, the probability of lumbar instability was 58.1%. The area of joint effusion was positively correlated with lumbar stability and the LSA. When the area of effusion was 0.2cm2, the probability of lumbar instability was 58.9%. A bilateral effusion signal is more likely to indicate lumbar instability than a unilateral effusion signal. The distribution width and area of effusion were positively correlated with lumbar stability and LSA.

Lumbar spine MRI findings in asymptomatic elite male academy footballers: a case series

BackgroundUnderstanding common MRI findings may allow clinicians to appreciate the sport-specific effects on the lumbar spine, and to discern clinically significant pathology. Prevalence data regarding radiological abnormalities seen during the surveillance of asymptomatic elite footballers is, therefore, important to help understand injury mechanisms and to prevent associated injuries. The purpose of this study was to evaluate the magnetic resonance imaging (MRI) findings in the lumbar spines of asymptomatic elite male adolescent footballers.MethodsA prospective case-series study was carried out. MRI was performed using a 3T Siemens Prisma scanner including a 3D VIBE sequence in 18 asymptomatic male elite adolescent footballers recruited from a professional academy in England (mean age 17.8, range 16.9–18.6 years). The images were independently reported by two consultant musculoskeletal radiologists to achieve consensus opinion. Standardised classification criteria were used to assess and report abnormalities descriptively.ResultsFifteen players (15/18, 83%) showed ≥1 abnormalities, included facet degeneration, synovial cysts, disc degeneration, disc herniation, and pars injury. One player (1/18, 6%) had mild (Grade 1) facet joint arthropathy at L4/L5 and 3/18 (16.7%) showing evidence of bilateral facet joint effusions. Three synovial cysts were identified in 2/18 players (11%), 4/18 players (22%) presented asymptomatic pars injuries, with 4 showing a grade 2 subtotal stress fracture and 1 player a grade 4 chronic stress fracture seen on 3D VIBE sequencing. Disc degeneration at one or more levels was demonstrated in 7/18 players (38%). Disc herniation was present in 5/18 players (27%).ConclusionA range of unsuspected findings on MRI of the lumbar spine are common in elite adolescent footballers.

Retrodural space of Okada in the posterior ligamentous complex region: clinical and anatomical findings relevant to lumbar interlaminar epidural injection

BackgroundThe retrodural space of Okada is a potential space posterior to the ligamentum flavum that allows communication with the bilateral facet joints. However, the actual anatomy of this space has...

Icariin protects vertebral endplate chondrocytes against apoptosis and degeneration via activating Nrf-2/HO-1 pathway.

Cartilage endplate (CEP) plays important roles in the onset and progression of intervertebral disc degeneration (IVDD). Icariin (ICA) is the major active ingredient of Herba Epimedii and has various biological activities such as anti-inflammatory and antioxidant, which is used to treat many degenerative diseases. However, the effects and mechanism of ICA on endplate chondrocytes are still unclear. Herein, we studied the effects of ICA on CEP degeneration and elucidated the underlying mechanisms. Endplate chondrocytes were isolated, and TNF-α and TBHP were applied to mimic an IVDD pathological environment. Also, an IVDD mice model was established by transection of bilateral facet joints to investigate the protective effect of ICA in vivo. We found that ICA treatment inhibited the chondrocytes apoptosis and the decrease of extracellular matrix production in a dose-dependent manner. Our in vivo experiments demonstrated that ICA could ameliorate IVDD development and CEP calcification. We also found that the ICA-activated Nrf-2/HO-1 pathway thus promoted the Parkin-mediated mitophagy process and inhibited chondrocytes ferroptosis, thus alleviated redox imbalance and mitochondrial dysfunction and eventually improved cell survival. Knockdown of Nrf-2 using siRNA reversed the protective effect of ICA on endplate chondrocytes apoptosis and degeneration. In conclusion, our study demonstrated that ICA could protect against CEP degeneration and calcification under IVDD pathological conditions, the associated mechanism may be related to Nrf-2/HO-1-mediated mitophagy activation and ferroptosis inhibition. Our results suggest that ICA may be a potential effective medicine for IVDD prevention and treatment.

Posterior lumbar interbody fusion for dysplastic lumbar spondylolisthesis with high-grade slippage in two adolescent siblings: two case reports

BackgroundLumbar spondylolisthesis is reported to present with a familiar pattern, with the dysplastic type of spondylolysis being minor but more hereditary than the isthmic type. Siblings presenting during adolescence with neurological symptoms owing to high-grade dysplastic-type spondylolisthesis are rare.Case presentationThe older brother suffered from left leg pain and numbness and dysesthesia of the right posterior thigh and calf and could not walk without a crutch at the age of 15 years. He had canal stenosis with disc bulging and dysplastic bilateral facet joint at L5/S1. The L5 vertebral body was slipped anterior downward to S1, with a round-shaped S1 cranial endplate. We diagnosed dysplastic-type spondylolisthesis and performed posterior lumbar interbody fusion at L5/S with mild reduction and sublaminar wiring at L4/5. The younger brother had no neurological symptoms at age 14 years but suffered from bilateral lower leg numbness at age 18 years. He had canal stenosis with disc bulging at L4/5 and L5/S1 and dysplastic bilateral facet joint at L5/S1 with right pars defect. The L5 vertebral body was vertically displaced anterior to the S1 vertebral body, with an S1 round-shaped cranial endplate. We diagnosed dysplastic-type spondylolisthesis, and posterior lumbar interbody fusion at L4/5 and L5/S with reduction was performed. Their neurological symptoms of the lower legs disappeared, and interbody bone fusion was obtained.ConclusionsThe surgical technique for high-grade dysplastic spondylolisthesis remains controversial in terms of in situ fusion versus reduction. We recommend that surgery be performed promptly at the end of bone maturation because neurological symptoms often appear at the end of bone maturation. Because high-grade slips are rare but siblings may be present, the sibling should also be screened when dysplastic spondylolisthesis is detected.

P5. Monocarboxylate transporter expression directly affects degeneration of the intervertebral disc in mice

<h3>BACKGROUND CONTEXT</h3> Disc degeneration is the central component involved in numerous common spinal pathologies. Low back pain remains a leading cause of disability in the world, yet treatment remains nonspecific and of poor efficacy. Degenerative disc disease (DDD) affects millions of people every year, yet the mechanisms driving degeneration remain poorly understood. Recent work has shown that high levels of intracellular lactate are involved in driving disc degeneration. Whether this loss of ability to export lactate is specific to a few models or common across modes of degeneration is yet to be determined. <h3>PURPOSE</h3> We utilized different mouse models of intervertebral disc (IVD) degeneration in order to better understand the role of lactate and lactate transport in DDD. <h3>STUDY DESIGN/SETTING</h3> Randomized, controlled animal trial. <h3>PATIENT SAMPLE</h3> Female mice (C57BL/6J, n=30). <h3>OUTCOME MEASURES</h3> Mice were euthanized at 2, 4 and 8 weeks. The IVD was evaluated by histological and immunofluorescence (IF) analysis. RNA extraction from disc tissue was analyzed with QPCR. Data are presented as means +/-SD. <h3>METHODS</h3> Female mice (C57BL/6J, n=30) were randomly assigned to one of four models of disc degeneration: 1) lumbar disc poke, 2) tail disc poke, 3) spinal instability and 4) sham. In group 1, a retroperitoneal approach exposed the IVD of the lumbar spine, and a 27G needle was used to injure the disc. In group 2, the needle was inserted in the tail IVD. In group 3, lumbar instability is induced by resection of bilateral facet joints and supra/interspinous ligaments. A sham group was used for each. <h3>RESULTS</h3> In group 1 and 2, the degenerative process at 2, 4 and 8 weeks was characterized by loss of nucleus pulposus (NP) cells and the gradual increase in matrix components. The distinction between NP and annulus fibrosus (AF) or endplate cartilage (ECP) was lost. Sham mice had no significant disc degeneration. There was increased expression of COL10 and MMP13 in the NP and decreased expression of GLUT1 (NP marker) in the disc-poke groups. The expression of a central lactate transporter (MCT4) was also reduced in injured mice, and there was an increase in catabolic chondrocyte markers. In group 2 there was also decreasedhexokinase-2 (HK2) expression and an increase in MCT3 expression. In group 3, disordered AF was seen 2 weeks postoperatively, with decreased disc space and fewer NP cells. The proteoglycan inner layer of AF and periphery of NP were decreased at 8 weeks. If confirmed an increase in COL10 and MMP13 in the inner AF and NP. Both NP and CEP of sham mice maintained strong expression of MCT4 while the NP and CEP in injured mice had reduced expression of MCT4. <h3>CONCLUSIONS</h3> Our results demonstrate a common molecular pathway whereby discs degenerate after direct injury or after becoming unstable. In our model there is rapid degeneration of the IVD in mice who exhibit up/down-regulation of several key markers. Importantly, MCT4 is down-regulated, while MCT3 is upregulated. Decreased MCT4 expression is a key and common step in the degeneration of the IVD. While MCT4 is associated with lactate exportation, and its loss results in elevated intracellular lactate and disc degradation, MCT3 is rarely expressed and may be acting as a "rescue" lactate transporter here. Decreased HK2 gene expression led to reduced glycolysis and mitochondrial dysfunction, leading to increased formation of ROS and oxidative stress; HK2 may be important to disc degeneration. We demonstrated a regulatory role for lactate transport in DDD, with decreased lactate exportation common to different degenerative mechanisms. Promoting MCT4 or MCT3 gene expression may represent a novel therapeutic option in DDD. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Magnetic Resonance Imaging Proxies for Segmental Instability in Degenerative Lumbar Spondylolisthesis Patients.

Retrospective cohort study. The aim was to investigate whether findings on magnetic resonance imaging (MRI) can be proxies (MRIPs) for segmental instability in patients with degenerative lumbar spinal stenosis (LSS) and/or degenerative spondylolisthesis (LDS) L4/L5. LDS has a heterogeneous nature. Some patients have a dynamic component of segmental instability associated with LDS. Studies have shown that MRI can show signs of instability. Patients with LSS or LDS at L4/L5 undergoing decompressive surgery±fusion from 2010 to 2017, with preoperative standing lateral spine radiographs and supine lumbar MRI and enrolled in Danish national spine surgical database, DaneSpine. Instability defined as slip of >3mm on radiographs. Patients divided into two groups based upon presence of instability. Outcome measures: radiograph: sagittal slip (mm). MRIPs for instability: sagittal slip >3mm, facet joint angle (°), facet joint effusion (mm), disk height index (%), and presence of vacuum phenomena. Optimal thresholds for MRIPs was determined by receiver operating characteristic (ROC) curves and area under the curve (AUC). Logistic regression to investigate association between instability and MRIPs. Two hundred thirty-two patients: 47 stable group and 185 unstable group. The two groups were comparable with regard to baseline patient-reported outcome measures. Thresholds for MRIPs: bilateral facet joint angle ≥46°; bilateral facet effusion ≥1.5mm and disk height index ≥13%. Logistic regression showed statistically significant association with MRIPs except vacuum phenomena, ROC curve AUC of 0.951. By absence of slip on MRI logistic regression showed statistically significant association between instability on radiograph and the remaining MRIPs, ROC curve AUC 0.757. Presence of MRIPs for instability showed statistically significant association with instability and excellent ability to predict instability on standing radiograph in LSS and LDS patients. Even in the absence of slip on MRI the MRIPs had a good ability to discriminate presence of instability.

Circumferential Bone Fusion in Adult Spinal Deformity via Combination of Oblique Lateral Interbody Fusion and Grade 2 Posterior Column Osteotomy.

Retrospective study. The combination of oblique lateral interbody fusion (OLIF) with grade 2 posterior column osteotomy (PCO) is an effective treatment for adult spinal deformity. However, grade 2 PCO may lead to pseudoarthrosis because it involves complete removal of the bilateral posterior facet joints. The main study objective was to determine the achievement rate of anterior and posterolateral fusion resulting in circumferential fusion in patients who underwent combined OLIF and grade 2 PCO. This retrospective study included consecutive patients who underwent OLIF and grade 2 PCO. The group comprised a long fusion group, with fusion from the thoracic level to the ilium, and a short fusion group, with fusion within the lumbar region. The OLIF with percutaneous pedicle screw insertion group was also used for reference. The Brantigan-Steffee-Fraser classification was used to assess interbody fusion and Lenke classification for assessment of posterolateral fusion. Sixty-six patients with 109 lumbar levels were included in the study. We observed 100% anterior fusion in all 3 groups. The fusion rate for posterolateral fusion between the OLIF-grade 2 PCO group was 97%, with very low (3%) non-circumferential fusion (pseudoarthrosis only at the osteotomy site). In most cases, solid posterolateral fusions (Lenke A) occurred within 24 months. The combination of OLIF and grade 2 PCO resulted in circumferential fusion for most (97%) of the cases within 24 months. OLIF and grade 2 PCO are considered a good combination treatment to achieve sufficient lumbar lordosis and solid bone fusion.