Buckling of the Ligamentum Flavum in Patients with Lumbar Spinal Canal Stenosis.

STUDY DESIGN: Experimental study. OBJECTIVE: We sought to elucidate the association between ligamentum flavum thickening and tissue buckling, and the clinical and imaging factors related to buckling by comparing the ligamentum flavum thickness on MRI images and within the actual tissue. SUMMARY OF BACKGROUND DATA: Ligamentum flavum thickening is a main contributor to lumbar spinal canal stenosis. Buckling of the tissue may contribute to ligamentum flavum thickening along with tissue hypertrophy; however, this association has not been established conclusively. MATERIALS AND METHODS: Ligamentum flavum samples (135 ligament samples) from 70 patients with lumbar spinal canal stenosis were evaluated. The ligamentum flavum thicknesses on magnetic resonance imaging (MRI) and in the tissue samples were compared to assess for the presence of buckling. The ligamentum flavum samples were divided into groups with or without buckling based on the difference between their thicknesses on MRI and in the tissues. The Pearson correlation coefficient test was used to assess the relationships between the LF thicknesses on MRI and in the tissues, MRI-tissue difference and LF thickness in the tissues, and MRI-tissue difference and LF thickness on MRI. Further, differences between the buckling+ and buckling- groups were compared using the unpaired t-test (LF thickness on MRI, LF thickness in the tissues, age, disc angle, and disc height) and χ2 (disc level, disc degeneration, and receival/nonreceival of dialysis) test. RESULTS: The ligamentum flavum thickness on MRI and in the tissues had a positive linear relationship, although the thickness was estimated to be significantly larger on MRI than in the tissues themselves. The ligamentum flavum with buckling had a larger thickness on MRI, less tissue hypertrophy, more severe disc degeneration, and was present in patients with a higher rate of dialysis. There were no differences in age and disc height, angle, or level between the two groups. CONCLUSIONS: Buckling of the ligamentum flavum coexists with tissue hypertrophy and contributes to perceived ligamentum thickening on imaging. Buckling of the ligamentum flavum tends to occur in less hypertrophied tissues and is associated with the grade of disc degeneration and the presence of other characteristics associated with spinal degeneration.

A clinical case of lymphoma with hindlimb paresis due to mass formation in the spinal canal in a Japanese Black cow.

A 5-year-old Japanese Black cow presented with astasia. Bovine leukemia virus (BLV) was detected in the peripheral blood with lower proviral load (PVL). No enlargement of surface lymph nodes or lymphocytosis was observed. Necropsy revealed no enlarged lymph nodes in the thoracic, abdominal, or pelvic cavity. Spinal epidural and peri-medullary adipose tissue was increased in the spinal canal of lumbar to sacral vertebrae, Histopathological examination revealed tumor invasion of the epidural adipose tissue, and a diagnosis of B-cell lymphoma was made. The PVL in tumor tissue was higher, and monoclonal integration of BLV was confirmed. It was a rare case of bovine enzootic leukosis that formed a solitary mass around the spinal cord which might cause hindlimb paresis.

First incidence of extrarenal wilms tumor within the spinal canal in the adult population: a novel case report and literature review.

BACKGROUND: Wilms tumor (WT), also known as nephroblastoma, is rare in adults, accounting for merely 3% of all nephroblastomas or 0.2 cases per million individuals. Extrarenal Wilms tumor (ERWT) emerges outside the renal boundaries and comprises 0.5 to 1% of all WT cases, with even rarer incidences in adults. Oncogenic mutations associated with ectopic nephrogenic rests (NR) may contribute to ERWT development. Diagnosis involves surgical resection and pathology examination. Due to scarce cases, adults often rely on pediatric guidelines. We thoroughly searched PubMed, Scopus, and Web of Science databases to establish our case's uniqueness. To the best of our knowledge, this is the first documented incidence of extrarenal Wilms tumor within the spinal canal in the adult population. CASE PRESENTATION: A 22-year-old woman with a history of congenital lipo-myelomeningocele surgery as an infant presented with a 6-month history of back pain. This pain gradually resulted in limb weakness, paraparesis, and loss of bladder and bowel control. An MRI showed a 6 × 5 × 3 cm spinal canal mass at the L4-S1 level. Consequently, a laminectomy was performed at the L4-L5 level to remove the intramedullary tumor. Post-surgery histopathology and immunohistochemistry confirmed the tumor as ERWT with favorable histology without any teratomatous component. CONCLUSION: This report underscores the rarity of extrarenal Wilms tumor (ERWT) in adults, challenging conventional assumptions about its typical age of occurrence. It emphasizes the importance of clinical awareness regarding such uncommon cases. Moreover, the co-occurrence of spinal ERWTs and a history of spinal anomalies warrants further investigation.

Three-dimensional Spinal Canal Morphometric Analysis and Relevant Spinal Cord Occupational Ratios in Congenital Cervical Spinal Stenosis: A Classification Algorithm of the Stenosis Phenotypes and Data-driven Decompression Approach.

OBJECTIVES: No standardized magnetic resonance imaging (MRI) parameters have defined the 3-dimensional morphoanatomy and relevant spinal cord occupation ratios (occupation of spinal cord dimensions/similar dimensions within the spinal canal) in congenital cervical stenosis (CCS). METHODS: A retrospective, comparative analysis was conducted on 200 patients >18 years of age with myelopathy and CCS (mean age, 52.4 years) and 200 age-matched controls with no myelopathy or radiculopathy. The variables assessed from high resolution MRI included sagittal and axial spinal canal dimensions (MRI Torg-Pavlov ratios) from C3 to C7. Morphometric dimensions from the sagittal retrodiscal and retrovertebral regions as well as axial MRI dimensions were compared. Sagittal and axial spinal cord occupation ratios were defined and correlated with spinal canal dimensions. RESULTS: Multivariate analyses indicated reduced sagittal and axial anteroposterior (AP) spinal canal dimensions and a large reduction in transverse spinal canal dimensions at all spinal levels. There was a small significant correlation between AP sagittal spinal canal dimensions and axial transverse spinal canal dimensions at C3-C5, but not at C5-C6. Small correlations were noted between AP sagittal spinal canal dimensions and AP axial spinal cord and axial cross-sectional area occupation ratios at C3-C6, but there was no correlation with axial mediolateral spinal cord occupation ratios. CONCLUSIONS: The stenosis effect can involve any dimension, including the transverse spinal canal dimension, independent of other dimensions. Owing to the varied observed morphoanatomies, a classification algorithm that defines CCS specific phenotypes was formulated. Objectivizing the stenosis morphoanatomy may allow for data-driven patient-focused decompression approaches in the future.

Imaging of Adult Malignant Soft Tissue Tumors of the Spinal Canal: A Guide for Spine Surgeons.

BACKGROUND: Malignant soft tissue spinal canal tumors compromise 20% of all spinal neoplasms. They may be primary or metastatic lesions, originating from a diverse range of tissues within and surrounding the spinal canal. These masses can present as diverse emergencies such as secondary cauda equina syndrome, vascular compromise, or syringomyelia. Interpretation of malignant soft tissue spinal canal tumors imaging is an essential for non-radiologists in the setting of emergencies. This task is intricate due to a great radiologic pattern overlap among entities. METHODS: We present a step-by-step strategy that can guide nonradiologists identify a likely malignant soft tissue lesion in the spinal canal based on imaging features, as well as a review of the radiologic features of malignant soft tissue spinal canal tumors. RESULTS: Diagnosis of soft tissue spinal canal malignancies starts with the identification of the lesion's spinal level and its relationship to the dura and medulla. The second step consists of characterizing it as likely-malignant based on radiological signs like a larger size, ill-defined margins, central necrosis, and/or increased vascularity. The third step is to identify additional imaging features such as intratumoral hemorrhage or cyst formation that can suggest specific malignancies. The physician can then formulate a differential diagnosis. The most encountered malignant soft tissue tumors of the spinal canal are anaplastic ependymomas, anaplastic astrocytomas, metastatic tumors, lymphoma, peripheral nerve sheath tumors, and central nervous system melanomas. A review of the imaging features of every type/subtype of lesion is presented in this work. Although magnetic resonance imaging remains the modality of choice for spinal tumor assessment, other techniques such as dynamic contrast agent-enhanced perfusion magnetic resonance imaging or diffusion-weighted imaging could guide diagnosis in specific situations. CONCLUSIONS: In this review, diagnostic strategies for several spinal cord tumors were presented, including anaplastic ependymoma, metastatic spinal cord tumors, anaplastic and malignant astrocytoma, lymphoma, malignant peripheral nerve sheath tumors , and primary central nervous system melanoma. Although the characterization of spinal cord tumors can be challenging, comprehensive knowledge of imaging features can help overcome these challenges and ensure optimal management of spinal canal lesions.

Radiological Analysis of Cerebrospinal Fluid Dynamics at the Craniovertebral Junction Using Time-Spatial Labeling Inversion Pulse Magnetic Resonance Imaging in Patients with Cervical Spinal Canal Stenosis.

OBJECTIVE: Spondylotic changes in the cervical spine cause degeneration, leading to cervical spinal canal stenosis. This stenotic change can affect cerebrospinal fluid (CSF) dynamics by compressing the dural sac and reducing space in the subarachnoid space. We examined CSF dynamics at the craniovertebral junction (CVJ) using time-spatial labeling inversion pulse magnetic resonance imaging (Time-SLIP MRI) in patients with cervical spinal canal stenosis. METHODS: The maximum longitudinal movement of the CSF at the CVJ was measured as length of motion (LOM) in the Time-SLIP MRI of 56 patients. The sum of ventral and dorsal LOM was defined as the total LOM. Patients were classified into 3 groups depending on their spinal sagittal magnetic resonance imaging findings: control (n = 27, Kang classification grades 0 and 1), stenosis (n = 14, Kang classification grade 2), and severe stenosis (n = 15, Kang classification grade 3). RESULTS: Time-SLIP MRI revealed pulsatile movement of the CSF at the CVJ. The mean total, ventral, and dorsal LOM was 14.2 ± 9, 8.1 ± 5.7, and 3.8 ± 2.9 mm, respectively. The ventral LOM was significantly larger than the dorsal LOM. The total LOM was significantly smaller in the severe stenosis group (6.1 ± 3.4 mm) than in the control (16.0 ± 8.4 mm) or stenosis (11 ± 5.4 mm) groups (P < 0.001, Kruskal-Wallis H-test). In 5 patients, postoperative total LOM was improved after adequate decompression surgery. CONCLUSIONS: This study demonstrates that CSF dynamics at the CVJ are influenced by cervical spinal canal stenosis. Time-SLIP MRI is useful for evaluating CSF dynamics at the CVJ in patients with spinal canal stenosis.

Transient spinal cord dysfunction after surgery for intraspinal tumors: A case report.

RATIONALE: Limb dysfunction is not uncommon clinically after intramural tumor surgery. However, there are no relevant literature reports on the recovery of unilateral motor function caused by spinal cord dysfunction after short-term observation and treatment. The report of such cases is of great value for improving the cognition of postoperative complications of meningioma reducing misdiagnosis and providing reference for clinical treatment. PATIENT CONCERNS: A 73-year-old female patient with numbness and weakness in both lower limbs accompanied by unstable walking for 2 months. Combined with imaging data and postoperative pathological diagnosis, it was diagnosed as thoracic spinal meningioma. The patient experienced transient unilateral limb dysfunction after surgery. DIAGNOSES: Magnetic resonance imaging and its enhanced magnetic resonance imaging suggest a space occupying lesion on the left side of the spinal canal at the level of the thoracic 3 to 4 vertebral body, possibly a meningioma. The postoperative pathology was grade I meningioma. INTERVENTION: Administer 10 mL of dexamethasone, 1 g of methylprednisolone, and 250 mL of mannitol for treatment. OUTCOMES: After 3 hours, the patient's muscle strength gradually recovered, and after 12 hours, it was better than the preoperative level. CONCLUSION: Spinal cord dysfunction may occur after surgery for intraspinal meningioma in the upper thoracic spine. Unlike spinal cord dysfunction caused by spinal cord injury, this dysfunction is short-term and transient. The use of hormones and diuretics is a feasible solution that can quickly restore patient limb function.

Cranial subdural migrating to lumbar subdural space in a toddler.

Migrated spinal subdural haematoma (sSDH) is a significantly uncommon finding. This case involves a paediatric patient representing after cranial trauma with new abnormal gait and leg pain who was found to have a migrated sSDH. Literature review for reported cases of pathogenesis theories, causes and management was performed and summarised in this report. The authors concluded that new abnormal gait and leg pain in a paediatric patient with previous cranial trauma is an indication for spinal MRI if migrated subdural haematoma is suspected. Non-surgical management is generally tolerated, and steroids can be trialled for radiculopathy if clinically indicated.

Unilateral Approaches for Posterior Spinal Canal Decompression in Cervical Spondylotic Myelopathy-An Evaluation of Conceptual Feasibility.

BACKGROUND: Patients with cervical spondylotic myelopathy (CSM) can be treated with posterior approaches for spinal canal decompression. OBJECTIVE: We compared the patients' outcome after 2 different unilateral and a bilateral posterior approach for decompression to elucidate feasibility and potential procedure-related differences. METHODS: Medical records of 98 patients with CSM undergoing posterior decompression between 2012 and 2018 were assessed. Patients were divided into 3 groups: (1) unilateral interlaminar fenestration with over-the-top "undercutting" (laminotomy) for compression limited to a ligamentum flavum hypertrophy, (2) unilateral hemilaminectomy for lateralized compression with a combination of ligamentous hypertrophy and osseus stenosis, and (3) laminectomy/laminoplasty for circular osseous-ligamentous spinal canal narrowing. RESULTS: The mean age was 73 years (m:f = 1.4:1), and most frequent symptoms (mean duration: 15 months) were ataxia (69%) and sensory changes (57%). Main location of stenoses (median Naganawa Score = 3; mean anteroposterior spinal canal diameter = 7.7 ± 2.2 mm) was C3 to C6. Thirty-one percent of the patients were assigned for a laminotomy procedure, 20% for a hemilaminectomy, and 49% for a laminectomy/laminoplasty. There were no significant differences of patients' characteristics, blood loss, and operation time between the 3 groups. Independent from the mode of surgery, the spinal canal was significantly widened (median Naganawa Score = 0; mean anteroposterior diameter = 11.4 ± 3.6 mm) and myelopathy (mJOA Score) improved ( P < .001); a higher body mass index was significantly correlated with a worse mJOA improvement (r = 0.293/ P = .003). Quality of life (Short-Form 36v2 Health Survey/Neck Disability Index) and reduction of the neck pain level were similar in the 3 groups at last follow-up (mean: 28 months). CONCLUSION: To minimize patients' periprocedural burden in CSM with dorsal compression, individual tailoring of the posterior approach according to the underlying compressive pathology achieves sufficient decompression and comparable long-term results.

Spinal leptomeningeal hemangioblastomatosis occurring without craniospinal surgery in von Hippel-Lindau disease.

Hemangioblastomatosis represents an unusual and malignant leptomeningeal dissemination of hemangioblastoma (HB). It has been reported in patients with sporadic HB or von Hippel-Lindau (VHL) disease. Hemangioblastomatosis had been reported following resection of a primary HB lesion in all cases except one patient with a sporadic HB. We present a patient with VHL with several HBs at the brainstem, cerebellum, pituitary stalk and retina who developed spinal hemangioblastomatosis without previous craniospinal surgery. A whole spine MRI showed the spinal dissemination from the primary lesions. The patient received craniospinal radiotherapy due to the extensive spinal leptomeningeal dissemination and multiple HBs. MRI performed 12 months after the radiotherapy showed stability of the lesions.

Primary Benign Tumors of the Spinal Canal.

Benign tumors that grow in the spinal canal are heterogeneous neoplasms with low incidence; from these, meningiomas and nerve sheath tumors (neurofibromas and schwannomas) account for 60%-70% of all primary spinal tumors. Benign spinal canal tumors provoke nonspecific clinical manifestations, mostly related to the affected level of the spinal cord. These tumors present a challenge for the patient and healthcare professionals, for they are often difficult to diagnose and the high frequency of posttreatment complications. In this review, we describe the epidemiology, risk factors, clinical features, diagnosis, histopathology, molecular biology, and treatment of extramedullary benign meningiomas, osteoid osteomas, osteoblastomas, aneurysmal bone cysts, osteochondromas, neurofibromas, giant cell tumors of the bone, eosinophilic granulomas, hemangiomas, lipomas, and schwannomas located in the spine, as well as possible future targets that could lead to an improvement in their management.

Diagnosis and radiation therapy of an extensive myxoma in the retropharyngeal region infiltrating the cranial cervical vertebral canal in a dog.

An 8-year-old, intact Rottweiler-female dog presented due to an acute onset of lethargy, abnormal gait, and wheezing. Physical examination revealed stridor, cervical pain, and ambulatory tetraparesis. Magnetic resonance imaging-examination displayed a lobulated, fluid-filled mass extending from the sphenoid bone to C5, infiltrating the cranial vertebral canal causing extradural compression of the spinal cord and narrowing of the pharynx. An emergency debulking-surgery around the pharynx was performed. Histopathological findings were consistent with a myxoma. The remaining tumor was irradiated resulting in stable disease 6 months later. The dog died 18 months later due to aspiration pneumonia without clinical signs of neurologic or respiratory compromise.

Comparison between the coronal diameters of the cervical spinal canal and spinal cord measured using computed tomography and magnetic resonance imaging in Korean patients.

BACKGROUND: If the proportion of the spinal cord in the epidural space can be determined under C-arm fluoroscopy during cervical epidural block, a safe entry point for the epidural needle can be established. The aim of this study was the measurement of the cord to canal transverse diameter ratio of each cervical spines. METHODS: We retrospectively evaluated the imaging data of 100 patients who underwent both cervical computed tomography (CT) and cervical magnetic resonance imaging (MRI) at our hospital. We measured the diameters of the spinal canal and spinal cord from the 3rd cervical vertebra to the 1st thoracic vertebra (T1) at each level by using the patients' cervical CT and MRI images. The spinal cord and spinal canal diameters were measured in the transverse plane of the cervical MRI and CT images, respectively. RESULTS: The spinal cord to spinal canal diameter ratio was the highest at the 4th and 5th cervical vertebrae (0.64 ± 0.07) and the lowest at T1 (0.55 ± 0.06, 99% CI [0.535, 0.565]. CONCLUSIONS: Our findings suggest that the cord to canal transverse diameter ratio could be used as a reference to reduce direct spinal cord injuries during cervical epidural block under C-arm fluoroscopy. In the C-arm fluoroscopic image, if an imaginary line connecting the left and right innermost lines of the pedicles of T1 is drawn and if the needle is inserted into the outer one-fifth of the left and right sides, the risk of puncturing the spinal cord would be relatively reduced.

A Rare Case of Cysticercosis Involving the Whole Spinal Canal.

BACKGROUND: Cysticercosis is the commonest parasitic disease to affect the central nervous system (CNS). However, cysticercosis affecting the spine is extremely rare. We reported a rare case of cysticercosis involving the whole spinal canal in China. CASE PRESENTATION: A rare case of cysticercosis involving the entire spinal cord, in a 52-year-old Chinese man, was detected in 2021. Epidemiological investigation, clinical and etiological examination was performed. CONCLUSION: Since spinal cysticercosis is a rare but potentially life-threatening disease, clinicians should always consider the differential diagnosis of space-occupying lesions.

Femoral head to lower lumbar neural foramen distance as a novel radiographic parameter to predict postoperative stretch neuropraxia.

OBJECTIVE: Lumbosacral fractional curves in adult spinal deformity (ASD) patients often have sharp coronal curves resulting in significant pain and imbalance. Postoperative stretch neuropraxia after fractional curve correction can lead to discomfort and unsatisfactory outcomes. The goal of this study was to use radiographic measures to increase understanding of the relationship between postoperative stretch neuropraxia and fractional curve correction. METHODS: In 62 ASD patients treated from 2015 to 2018, radiographic review was performed, including measurement of the distance between the lower lumbar neural foramen (L4 and L5) in the concavity and convexity of the lumbosacral fractional curve and the ipsilateral femoral heads (FHs; L4-FH and L5-FH) in pre- and postoperative anteroposterior spine radiographs. The largest absolute preoperative to postoperative change in distance between the lower lumbar neural foramen and the ipsilateral FH (ΔL4/L5-FH) was used for analysis. Chi-square analyses, independent and paired t-tests, and logistic regression were performed to study the relationship between L4/L5-FH and stretch neuropraxia for categorical and continuous variables, respectively. RESULTS: Of the 62 patients, 13 (21.0%) had postoperative stretch neuropraxia. Patients without postoperative stretch neuropraxia had an average ΔL4-FH distance of 16.2 mm compared to patients with stretch neuropraxia, who had an average ΔL4-FH distance of 31.5 mm (p < 0.01). Patients without postoperative neuropraxia had an average ΔL5-FH distance of 11.1 mm compared to those with stretch neuropraxia, who had an average ΔL5-FH distance of 23.0 mm (p < 0.01). Chi-square analysis showed that patients had a 4.78-fold risk of developing stretch neuropraxia with ΔL4-FH > 20 mm (95% CI 1.3-17.3) and a 5.17-fold risk of developing stretch neuropraxia with ΔL5-FH > 15 mm (95% CI 1.4-18.7). Logistic regression analysis indicated that the odds of developing stretch neuropraxia were 15:1 with a ΔL4-FH > 20 mm (95% CI 3-78) and 21:1 with a ΔL5-FH > 15 mm (95% CI 4-113). CONCLUSIONS: The novel ΔL4/L5-FH distances are strongly associated with postoperative stretch neuropraxia in ASD patients. A ΔL4-FH > 20 mm and ΔL5-FH > 15 mm significantly increase the odds for patients to develop postoperative stretch neuropraxia.

Hypertrophy of the ligamentum flavum in lumbar spinal canal stenosis is associated with abnormal accumulation of specific lipids.

Ligamentum flavum hypertrophy (HLF) is the most important component of lumbar spinal canal stenosis (LSCS). Analysis of hypertrophied ligamentum flavum (HLF) samples from patients with LSCS can be an important que. The current study analyzed the surgical samples of HLF samples in patients with LCSC using quantitative and qualitative high performance-liquid chromatography and mass spectrometry. We collected ligamentum flavum (LF) tissue from twelve patients with LSCS and from four patients with lumbar disk herniation (LDH). We defined LF from LSCS patients as HLF and that from LDH patients as non-hypertrophied ligamentum flavum (NHLF). Total lipids were extracted from the LF samples and evaluated for quantity and quality using liquid chromatography and mass spectrometry. The total lipid amount of the HLF group was 3.6 times higher than that of the NHLF group. Phosphatidylcholines (PCs), ceramides (Cers), O-acyl-ω-hydroxy fatty acids (OAHFAs), and triglycerides (TGs) in the HLF group were more than 32 times higher than those of the NHLF group. PC(26:0)+H+, PC(25:0)+H+, and PC(23:0)+H+ increased in all patients in the HLF group compared to the NHLF group. The thickness of the LF correlated significantly with PC(26:0)+H+ in HLF. We identified the enriched specific PCs, Cers, OAHFAs, and TGs in HLF.