Spinal Dura Research Articles

Dural manipulation coinciding with transient asystole during lumbar spine surgery: illustrative case.

Hemodynamic disturbances during lumbar spine surgeries have proven to be exceptionally rare, with only seven published cases demonstrating instances where intraoperative dural manipulation coincided with bradycardia, hypotension, and/or asystole. The authors present the case of a 39-year-old male with a history of chronic low-back pain and leg weakness. Imaging demonstrated a disc herniation at L5-S1, resulting in impingement of the left S1 traversing nerve root. The patient agreed to surgery. The preoperative workup was unremarkable. While retracting the S1 nerve root, transient asystole occurred when the S1 nerve root was manipulated, causing the patient's heart rate to drop from 51 to 0 bpm. Manipulating the nerve root once again triggered a similar event, and upon cessation of the surgical stimulus, the patient's heart rate spontaneously returned to baseline. Other potential causes of these hemodynamic perturbations were excluded. As in other reported cases, each cardiovascular disturbance corresponded with either direct or indirect dural manipulation. Given the limited number of lumbar spinal cases reported to have undergone hemodynamic perturbances via dural manipulation, this case report provides evidence for the likelihood of a spinal-cardiac reflex between the cardiovascular system and the spinal dura mater. https://thejns.org/doi/10.3171/CASE24158.

Iatrogenic needle penetrating injury of cervical spinal cord: a case of fatal therapeutic complication.

A 52-year-old woman with of neck pain underwent percutaneous neck injection of local anesthetic and a corticosteroid without image guidance. She collapsed asystolic during the procedure was resuscitated and then died after 2 weeks in the intensive care unit with hypoxic encephalopathy. Complete postmortem examination included additional posterior neck dissection and cervical spinal cord removal with intact dura mater. The entire cervical spinal cord with the dura and leptomeninges was embedded in an oriented sequence of several paraffin blocks. Serial sections of each selected blocks were then studied to locate a putative puncture site. Serial sections from the third and fourth cervical levels (C3-C4) were stained with luxol fast blue-hematoxylin-eosin, iron stain, trichrome stain, and immunostained for b-amyloid precursor protein, and CD68. Histological examination revealed a linear needle track with a subacute healing reaction. The path included the dorsal spinal dura, arachnoid, and the left dorsal column. Clinicopathological correlation and the cause of death are discussed. Careful planning, dissection, sampling, and oriented serial sectioning with immunostaining were key points to document the injuries and understand this case.

Sensory nerve formations in the myodural bridge complex of adult humans

The myodural bridge complex (MDBC) consists of connective tissue bands connecting the spinal dura mater to the suboccipital muscles passing throughout the posterior atlanto-occipital and atlanto-axial spaces. It is a universal evolutionarily conserved anatomical structure present in most vertebrate species including humans. Its physiology is unknown, but it is thought that it may be related to cerebrospinal fluid circulation. On the other hand, there is no information about the possible innervation of MDBC in humans. In the present study, immunohistochemistry (S100 protein and neurofilament proteins) was used to study the innervation of MDBC in five specimens of adult human cadavers. In all cases, nerve profiles were observed forming isolated nerve fibers or small nerve bundles, sometimes associated with blood vessels. In one case (1/5), at the level of the junction of the MDBC with the posterior rectus capitis minor muscle, complex capsulated formations containing a variable number of sensory nerve formations were found. We consider that such formations may be related to the proprioceptor system of the suboccipital muscles, but further studies are needed to determine their frequency, density and possible function.

On the spinal venous sinus of Alligator mississippiensis.

The epidural space of the American alligator (Alligator mississippiensis) is largely filled by a continuous venous sinus. This venous sinus extends throughout the trunk and tail of the alligator, and is continuous with the dural sinuses surrounding the brain. Segmental spinal veins (sl) link the spinal venous sinus (vs) to the somatic and visceral venous drainage. Some of these sl, like the caudal head vein along the occipital plate of the skull, are enlarged, suggesting more functional linkage. No evidence of venous valves or external venous sphincters was found associated with the vs; the relative scarcity of smooth muscle in the venous wall of the sinus suggests limited physiological regulation. The proatlas (pr), which develops between the occipital plate and C1 in crocodylians, is shaped like a neural arch and is fused to the dorsal surface of the vs. The present study suggests that the pr may function to propel venous blood around the brain and spinal cord. The vs effectively encloses the spinal dura, creating a tube-within-a-tube system with the (smaller volume) spinal cerebrospinal fluid (CSF). Changes in venous blood pressure, as are likely during locomotion, would impact dural compliance and CSF pressure waves propagating along the spinal cord.

Postnatal meningeal CSF transport is primarily mediated by the arachnoid and pia maters and is not altered after intraventricular hemorrhage-posthemorrhagic hydrocephalus

BackgroundCSF has long been accepted to circulate throughout the subarachnoid space, which lies between the arachnoid and pia maters of the meninges. How the CSF interacts with the cellular components of the developing postnatal meninges including the dura, arachnoid, and pia of both the meninges at the surface of the brain and the intracranial meninges, prior to its eventual efflux from the cranium and spine, is less understood. Here, we characterize small and large CSF solute distribution patterns along the intracranial and surface meninges in neonatal rodents and compare our findings to meningeal CSF solute distribution in a rodent model of intraventricular hemorrhage-posthemorrhagic hydrocephalus. We also examine CSF solute interactions with the tela choroidea and its pial invaginations into the choroid plexuses of the lateral, third, and fourth ventricles.Methods1.9-nm gold nanoparticles, 15-nm gold nanoparticles, or 3 kDa Red Dextran Tetramethylrhodamine constituted in aCSF were infused into the right lateral ventricle of P7 rats to track CSF circulation. 10 min post-1.9-nm gold nanoparticle and Red Dextran Tetramethylrhodamine injection and 4 h post-15-nm gold nanoparticle injection, animals were sacrificed and brains harvested for histologic analysis to identify CSF tracer localization in the cranial and spine meninges and choroid plexus. Spinal dura and leptomeninges (arachnoid and pia) wholemounts were also evaluated.ResultsThere was significantly less CSF tracer distribution in the dura compared to the arachnoid and pia maters in neonatal rodents. Both small and large CSF tracers were transported intracranially to the arachnoid and pia mater of the perimesencephalic cisterns and tela choroidea, but not the falx cerebri. CSF tracers followed a similar distribution pattern in the spinal meninges. In the choroid plexus, there was large CSF tracer distribution in the apical surface of epithelial cells, and small CSF tracer along the basolateral surface. There were no significant differences in tracer intensity in the intracranial meninges of control vs. intraventricular hemorrhage-posthemorrhagic hydrocephalus (PHH) rodents, indicating preserved meningeal transport in the setting of PHH.ConclusionsDifferential CSF tracer handling by the meninges suggests that there are distinct roles for CSF handling between the arachnoid-pia and dura maters in the developing brain. Similarly, differences in apical vs. luminal choroid plexus CSF handling may provide insight into particle-size dependent CSF transport at the CSF-choroid plexus border.

Artificial spinal dura mater made of gelatin microfibers and bioadhesive for preventing cerebrospinal fluid leakage.

Artificial spinal dura mater was designed by combining solution blow-spun gelatin microfibers and dopamine-capped polyurethane bioadhesive. Notably, the gelatin microfibers had a special pore structure, good water adsorption capability, and excellent burst pressure resistance. The bioadhesive layer contributed to the excellent sealing performance in the wet state. This material provides a promising alternative as an artificial spinal dura mater to prevent cerebrospinal fluid leakage.

Microscopic observation of collagen fibers in spinal dura mater under uniaxial stretch

Microscopic observation of collagen fibers in spinal dura mater under uniaxial stretch

The influence of spinal venous blood pressure on cerebrospinal fluid pressure

In Alligator mississippiensis the spinal dura is surrounded by a venous sinus; pressure waves can propagate in the spinal venous blood, and these spinal venous pressures can be transmitted to the spinal cerebrospinal fluid (CSF). This study was designed to explore pressure transfer between the spinal venous blood and the spinal CSF. At rest the cardiac-related CSF pulsations are attenuated and delayed, while the ventilatory-related pulsations are amplified as they move from the spinal venous blood to the spinal CSF. Orthostatic gradients resulted in significant alterations of both cardiac- and ventilatory-related CSF pulsations. Manual lateral oscillations of the alligator’s tail created pressure waves in the spinal CSF that propagated, with slight attenuation but no delay, to the cranial CSF. Oscillatory pressure pulsations in the spinal CSF and venous blood had little influence on the underlying ventilatory pulsations, though the same oscillatory pulsations reduced the ventilatory- and increased the cardiac-related pulsations in the cranial CSF. In Alligator the spinal venous anatomy creates a more complex pressure relationship between the venous and CSF systems than has been described in humans.

The relationship between myodural bridge, atrophy and hyperplasia of the suboccipital musculature, and cerebrospinal fluid dynamics

The Myodural Bridge (MDB) is a physiological structure that is highly conserved in mammals and many of other tetrapods. It connects the suboccipital muscles to the cervical spinal dura mater (SDM) and transmits the tensile forces generated by the suboccipital muscles to the SDM. Consequently, the MDB has broader physiological potentials than just fixing the SDM. It has been proposed that MDB significantly contributes to the dynamics of cerebrospinal fluid (CSF) movements. Animal models of suboccipital muscle atrophy and hyperplasia were established utilizing local injection of BTX-A and ACE-031. In contrast, animal models with surgical severance of suboccipital muscles, and without any surgical operation were set as two types of negative control groups. CSF secretion and reabsorption rates were then measured for subsequent analysis. Our findings demonstrated a significant increase in CSF secretion rate in rats with the hyperplasia model, while there was a significant decrease in rats with the atrophy and severance groups. We observed an increase in CSF reabsorption rate in both the atrophy and hyperplasia groups, but no significant change was observed in the severance group. Additionally, our immunohistochemistry results revealed no significant change in the protein level of six selected choroid plexus-CSF-related proteins among all these groups. Therefore, it was indicated that alteration of MDB-transmitted tensile force resulted in changes of CSF secretion and reabsorption rates, suggesting the potential role that MDB may play during CSF circulation. This provides a unique research insight into CSF dynamics.

Risk Factors for Cerebrospinal Fluid Leakage After Extradural Spine Surgery: A Meta-Analysis and Systematic Review

Cerebrospinal fluid (CSF) leakage is 1 of the common complications of spine surgery and is largely caused by intraoperative or postoperative dural tears. Associations of different factors with postoperative CSF leakage have not been consistent. In this study we aimed to identify demographic, disease-related, and surgical risk factors for CSF leakage after extradural spine surgery in a systematic review and meta-anlysis. The PubMed, EMBASE, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure, Chinese Wanfang data, Chinese Weipu Database, and SinoMed databases were searched from inception until October 24, 2022. Fixed-effects or random-effects models were used to calculate odds ratios and 95% confidence intervals. The quality of observational studies was evaluated using the Newcastle-Ottawa scale instrument. A total of 15 observational studies with 1,719,923 participants were included in this systematic review. All studies had a Newcastle-Ottawa scale score greater than or equal to 6. Age older than 70years, smoking, ossification of the posterior longitudinal ligament, adhesion of spinal dura, spinal canal stenosis, cervical fracture, spondylolisthesis, revision surgery, and multiple surgical segments were all related to CSF leakage in the pooled analysis. Obesity and disease duration>1year were not associated with the leakage of CSF. This study will provide a reference for the identification of patients at high risk of developing CSF leakage, which suggests clinicians to strengthen the observation of drainage fluid in high-risk groups.

Clinical characteristics and risk factors of intracranial hemorrhage after spinal surgery.

Intracranial hemorrhage after spinal surgery is a rare and devastating complication. To investigate the economic burden, clinical characteristics, risk factors, and mechanisms of intracranial hemorrhage after spinal surgery. A retrospective cohort study was conducted from January 1, 2015, to December 31, 2022. Patients aged ≥ 18 years, who had undergone spinal surgery were included. Intracranial hemorrhage patients were selected after spinal surgery during hospitalization. Based on the type of spinal surgery, patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage. The patients' pre-, intra-, and post-operative data and clinical manifestations were recorded. A total of 24472 patients underwent spinal surgery. Six patients (3 males and 3 females, average age 71.3 years) developed intracranial hemorrhage after posterior spinal fusion procedures, with an incidence of 0.025% (6/24472). The prevailing type of intracranial hemorrhage was cerebellar hemorrhage. Two patients had a poor clinical outcome. Based on the type of surgery, 30 control patients were randomly matched in 1:5 ratio. The intracranial hemorrhage group showed significant differences compared with the control group with regard to age (71.33 ± 7.45 years vs 58.39 ± 8.07 years, P = 0.001), previous history of cerebrovascular disease (50% vs 6.7%, P = 0.024), spinal dura mater injury (50% vs 3.3%, P = 0.010), hospital expenses (RMB 242119.1 ± 87610.0 vs RMB 96290.7 ± 32029.9, P = 0.009), and discharge activity daily living score (40.00 ± 25.88 vs 75.40 ± 18.29, P = 0.019). The incidence of intracranial hemorrhage after spinal surgery was extremely low, with poor clinical outcomes. Patient age, previous stroke history, and dura mater damage were possible risk factors. It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.

DURAL MECHANICAL RESPONSES TO LOAD-CONTROLLED ASYMMETRIC BIAXIAL STRETCH

This study conducted a series of biaxial stretching tests on the spinal dura mater. To investigate the specific effects of different loading patterns on mechanical responses of the dura mater, load-controlled asymmetric (longitudinal vs. circumferential loading at 1:0.5 and 0.5:1 ratios) and equi-load (longitudinal vs. circumferential at a 1:1 ratio) biaxial stretching tests were performed. The dural meninge was found to be most compliant when a circumferentially dominant loading pattern (longitudinal vs. circumferential at a 0.5:1 ratio or physiological biaxial stretch) was used. Additionally, physiological biaxial stretch resulted in the lowest strain energy density in the toe region of stress–strain curves, i.e., physiological deformation ranges, whereas mechanical loading caused abruptly stiffening of the linear region of stress–strain curves even under circumferentially dominant loading. On the other hand, stress relaxation and elastin content of the dural tissue had no effect on stored strain energy density within the range of biaxial stretch tested in this study. These results indicate that physiological biaxial stretching contributes to structural protection of the spinal cord and the spinal dura, which may be attributable to changes in the arrangement of embedded collagen fibers and concomitant mechanical interactions with surrounding tissues.

Factors affecting administration of palliative care in primary central nervous system tumors: An NCDB analysis.

e24146 Background: Primary central nervous system (CNS) tumors are a diverse group of neoplasms that can vary greatly in terms of their cellular origin, histological features, clinical behavior, and prognosis. Many diagnoses leave patients with a poor prognosis and an impaired quality of life. Palliative care (PC) has long been used as a means to improve quality of life and symptoms associated with debilitating malignancies; however, its use in CNS tumors is not well characterized. Yet, the plethora of life-altering symptoms such as gait impairment, cognitive decline, motor deficits, and seizures provide a need for further multidisciplinary approaches to integrating PC with primary CNS tumor diagnoses. We aim to assess factors that influence the receipt of PC in the current data on central nervous system tumor patients and assess differences in overall survival. Methods: This study retrospectively evaluated the use of PC in patients with single primary malignant central nervous system tumors (gliomas, neuroepitheliomatous neoplasms, and meningiomas) diagnosed and recorded in the National Cancer Database (NCDB) between 2004 and 2020. Patients were identified by ICD-O-3 coding and patients with other malignancies were excluded. Multivariable logistic regression was performed to evaluate associations between patient characteristics and the use of PC, and Kaplan-Meier curves with log-rank analysis were used to determine survival for each group. Results: After excluding patients without information on utilization of PC, a total of 9295 patients with primary CNS tumors were considered in the final analysis. Overall, 1.31% received palliative care. From patients receiving palliative care, 81.1-93.4% received non-curative treatment with surgery, radiation, chemotherapy, or a combination of one or more of these modalities with additional pain management. Odds of receiving palliative care were decreased in black patients, patients who received non-palliative surgical treatment, patients with a primary tumor site at the optic chiasm, patients with unilateral tumors, and patients with private, medicaid, other government, or unknown insurance status. Odds of receiving palliative care were increased with increased Charlson-Deyo Score, in patients receiving non-palliative systemic or radiation treatment, and patients with a primary site at the spinal dura. Utilization of PC was associated with a decreased 1-year and 5-year overall survival. Conclusions: PC use in CNS tumors was influenced by tumor location, treatment type, insurance status, patient race, and comorbidity index. This study demonstrates the areas in which use of PC utilization is still lacking across a diverse set of CNS tumors and patients. Further exploration is needed into the integration of palliative care broadly across these malignancies as it still remains low despite the abundance of quality-of-life altering symptoms.

Superficial siderosis: comparison of two cases indicates two distinct diagnostic entities. Illustrative cases.

Superficial siderosis is the deposition of hemosiderin in the superficial layers of the central nervous system. It has been described in patients with chronic leakage of blood into the cerebrospinal fluid or with amyloid angiopathy, often associated with Alzheimer's disease (AD). We present two cases of superficial siderosis with vastly different symptomatologies and treatment courses. The patient in case 1 had diffuse superficial siderosis demonstrated on T2-weighted magnetic resonance imaging (MRI), appearing mostly in the inferior cerebellum and extending throughout the neuraxis. He presented with hearing loss, spasticity, gait abnormalities, and urinary incontinence. Ultimately, surgical exploration of the thoracic spinal dura revealed an arteriovenous fistula, which was obliterated. His clinical course stabilized but with persistent deficits. The patient in case 2 had a family history of AD and underwent MRI to evaluate for memory impairment, which demonstrated superficial siderosis of the left occipital lobe. Lumbar puncture demonstrated only traumatic contamination by red blood cells, but tau protein analysis was consistent with the diagnosis of AD. Superficial siderosis is a diagnostic term prompted by findings on MRI that can arise due to two different pathological entities. The diagnosis in case 1 should be termed diffuse superficial siderosis and in case 2 should be termed lobar cortical siderosis.

Blockade of VEGFR3 signaling leads to functional impairment of dural lymphatic vessels without affecting autoimmune neuroinflammation.

The recent discovery of lymphatic vessels (LVs) in the dura mater, the outermost layer of meninges around the central nervous system (CNS), has opened a possibility for the development of alternative therapeutics for CNS disorders. The vascular endothelial growth factor C (VEGF-C)/VEGF receptor 3 (VEGFR3) signaling pathway is essential for the development and maintenance of dural LVs. However, its significance in mediating dural lymphatic function in CNS autoimmunity is unclear. We show that inhibition of the VEGF-C/VEGFR3 signaling pathway using a monoclonal VEGFR3-blocking antibody, a soluble VEGF-C/D trap, or deletion of the Vegfr3 gene in adult lymphatic endothelium causes notable regression and functional impairment of dural LVs but has no effect on the development of CNS autoimmunity in mice. During autoimmune neuroinflammation, the dura mater was only minimally affected, and neuroinflammation-induced helper T (TH) cell recruitment, activation, and polarization were significantly less pronounced in the dura mater than in the CNS. In support of this notion, during autoimmune neuroinflammation, blood vascular endothelial cells in the cranial and spinal dura expressed lower levels of cell adhesion molecules and chemokines, and antigen-presenting cells (i.e., macrophages and dendritic cells) had lower expression of chemokines, MHC class II-associated molecules, and costimulatory molecules than their counterparts in the brain and spinal cord, respectively. The significantly weaker TH cell responses in the dura mater may explain why dural LVs do not contribute directly to CNS autoimmunity.

A Neglected Normal Anatomical Structure in Mammal: A Study in Bats and Tree Shrews

The myodural bridge is a dense connective tissue connecting muscles and ligaments to the spinal dura mater in the atlanto-occipital interspace. Some researchers believe that the myodural bridge may play a vital physiological role. It is possible, for instance, that the prevention of spinal dura mater infoldings might be involved in regulated cerebrospinal fluid circulation. For instance, it is possible to prevent spinal dura mater infoldings, regulating cerebrospinal circulation. Bats are nocturnal and the only mammals that can perform a genuine and sustained flight, whereas tree shrews are arboreal mammals that often climb to a high altitude of about 10,000 feet. Both animals have lifestyles that are different from other previously studied mammals. The study of these two animals will shed further light on the existence of the myodural bridge in mammals. Gross anatomical dissection was used to observe the connections between the deep muscles of the neck and the dura mater at the level of the atlanto-occipital interspace. The existing structures were analyzed using conventional and special histological staining techniques. The suboccipital regions in bats and tree shrews contained the rectus capitis dorsal major (RCDma), rectus capitis dorsal minor (RCDmi), oblique capitis anterior (OCA), and oblique capitis posterior (OCP). Dense connective tissue connects the RCDmi to the posterior atlanto-occipital membrane (PAOM) and the latter to the spinal dura mater. The myodural bridge in these mammals shares a similar structure to the myodural bridge in humans. Histological analyses confirmed that the connective fibers of the myodural bridge were primarily type I collagen fibers. In this study, it is supplemented by the existence of the myodural bridge in mammals. This further demonstrates that myodural bridge widely exists in the normal anatomy of mammals. This provides morphological support for a comparative anatomical study of the physiological function of the myodural bridge.

Effects of cervical rotatory manipulation on the cervical spinal cord complex with ossification of the posterior longitudinal ligament in the vertebral canal: A finite element study.

Background: There are few studies focusing on biomechanism of spinal cord injury according to the ossification of the posterior longitudinal ligament (OPLL) during cervical rotatory manipulation (CRM). This study aimed to explore the biomechanical effects of CRM on the spinal cord, dura matter and nerve roots with OPLL in the cervical vertebral canal. Methods: Three validated FE models of the craniocervical spine and spinal cord complex were constructed by adding mild, moderate, and severe OPLL to the healthy FE model, respectively. We simulated the static compression of the spinal cord by OPLL and the dynamic compression during CRM in the flexion position. The stress distribution of the spinal cord complex was investigated. Results: The cervical spinal cord experienced higher von Mises stress under static compression by the severe OPLL. A higher von Mises stress was observed on the spinal cord in the moderate and severe OPLL models during CRM. The dura matter and nerve roots had a higher von Mises stress in all three models during CRM. Conclusion: The results show a high risk in performing CRM in the flexion position on patients with OPLL, in that different occupying ratios in the vertebral canal due to OPLL could significantly increase the stress on the spinal cord complex.

Radiation disrupts the protective function of the spinal dura mater in a mouse model of tumor-induced spinal cord compression

Radiation disrupts the protective function of the spinal dura mater in a mouse model of tumor-induced spinal cord compression

Collagen-Based Grafts and Autologous Dura Replacement in Patients with Dura Abnormalities: A Retrospective Comparative Evaluation

Introduction: Accidental spinal anomalies of the spinal dura mater are the source of cerebrospinal fluid (CSF) leakage. Typically, dura abnormalities are identified in 3 percent of endoscopic lumbar discectomy cases. Objective: The purpose of the current research was to evaluate the results of autologous dura replacement versus collagen-based grafts in individuals with dura deformities. Methods: The Institute of Neurosurgery at Liaquat National Hospital Karachi undertook this randomized evaluation to identify the most effective therapy for dura mater defects. Employing non-probability random selection, 82 cases among both sexes were selected. Participants were divided randomly into two subgroups i.e. Group 1A received an autologous graft for dura restoration, whereas Group 2B received a semi-synthetic dura replacement. A skilled surgeon led a medical team of six people who completed the entire process. Results: The operation duration for semi-synthetic collagen was significantly reduced. There was a 40 minute variation in total time spent by the two groups. Autologous grafts showed ideal tightness and better flexibility and fair workability on the other hand semi-synthetic collagen showed better tightness and workability and ideal flexibility. Postoperative hospital stays were seen to be 26 + 2.5 hours in Group 1A whereas they were 23 + 2.5 hours for Group B. Conclusion: According to the aforementioned findings, an accessible, secure, and efficient substitution for an autologous graft for dura restoration in dura abnormalities is the use of a semi-synthetic collagen substitute. Keywords: semi-synthetic collagen substitute, cerebrospinal fluid, dura abnormalities, autologous graft.

Tensile properties of human spinal dura mater and pericranium

Autologous pericranium is a promising dural graft material. An optimal graft should exhibit similar mechanical properties to the native dura, but the mechanical properties of human pericranium have not been characterized, and studies of the biomechanical performance of human spinal dura are limited. The primary aim of this study was to measure the tensile structural and material properties of the pericranium, in the longitudinal and circumferential directions, and of the dura in each spinal region (cervical, thoracic and lumbar) and in three directions (longitudinal anterior and posterior, and circumferential). The secondary aim was to determine corresponding constitutive stress–strain equations using a one-term Ogden model. A total of 146 specimens were tested from 7 cadavers. Linear regression models assessed the effect of tissue type, region, and orientation on the structural and material properties. Pericranium was isotropic, while spinal dura was anisotropic with higher stiffness and strength in the longitudinal than the circumferential direction. Pericranium had lower strength and modulus than spinal dura across all regions in the longitudinal direction but was stronger and stiffer than dura in the circumferential direction. Spinal dura and pericranium had similar strain at peak force, toe, and yield, across all regions and directions. Human pericranium exhibits isotropic mechanical behavior that lies between that of the longitudinal and circumferential spinal dura. Further studies are required to determine if pericranium grafts behave like native dura under in vivo loading conditions. The Ogden parameters reported may be used for computational modeling of the central nervous system.Graphical abstract