Comparing adjacent segment biomechanics between anterior and posterior cervical fusion using patient-specific finite element modeling.

Study Design: This study employed a patient-specific finite element model.

Purpose: To quantify the effect of anterior and posterior surgical approaches on adjacent segment biomechanics of the patient-specific spine and spinal cord.

Overview Of Literature: Adjacent segment degeneration (ASD) is a well-documented complication following cervical fusion, typically resulting from accelerated osteoligamentous deterioration and subsequent symptomatic neural compression.

Using Finite Element Models to Assess Spinal Cord Biomechanics after Cervical Laminoplasty for Degenerative Cervical Myelopathy.

Cervical laminoplasty is an established motion-preserving procedure for degenerative cervical myelopathy (DCM). However, patients with pre-existing cervical kyphosis often experience inferior outcomes compared to those with straight or lordotic spines. Limited dorsal spinal cord shift in kyphotic spines post-decompression and increased spinal cord tension may contribute to poor neurological recovery and spinal cord injury.

Recovery Trajectories of Patient-reported Outcomes After Surgery for Degenerative Cervical Myelopathy: A Bayesian Latent Class Modeling Approach.

Study Design: Retrospective study.

Objective: The aim of this study was to identify recovery trajectory clusters after surgery for degenerative cervical myelopathy (DCM), as well as to determine clinical and imaging characteristics associated with functional recovery trajectories.

Background: Accurate prediction of postsurgical neurological recovery for the individual patient with DCM is challenging due to varying patterns of functional recovery.

Effect of sagittal alignment on spinal cord biomechanics in the stenotic cervical spine during neck flexion and extension.

Spinal cord stress and strain contribute to degenerative cervical myelopathy (DCM), while cervical kyphosis is known to negatively impact surgical outcomes. In DCM, the relationship between spinal cord biomechanics, sagittal alignment, and cord compression is not well understood. Quantifying this relationship can guide surgical strategies.

Impact of postsurgical rehabilitation on outcomes for degenerative cervical myelopathy.

Objective: Despite widespread use, there is limited evidence to support postsurgical rehabilitation to enhance neurological recovery after surgery for degenerative cervical myelopathy (DCM). Outcomes research for DCM seldom accounts for the effect of postsurgical rehabilitation. The aim of this study was to quantify the impact of postsurgical rehabilitation on outcomes after surgery for DCM.

Interventions to Optimize Spinal Cord Perfusion in Patients With Acute Traumatic Spinal Cord Injury: An Updated Systematic Review.

Study Design: Systematic review update.

Objectives: Interventions that aim to optimize spinal cord perfusion are thought to play an important role in minimizing secondary ischemic damage and improving outcomes in patients with acute traumatic spinal cord injuries (SCIs). However, exactly how to optimize spinal cord perfusion and enhance neurologic recovery remains controversial.

Complex Neck Loading and Injury Tolerance in Lateral Bending With Head Rotation From Human Cadaver Tests.

Advancements in automated vehicles may position the occupant in postures different from the current standard posture. It may affect human tolerance responses. The objective of this study was to determine the lateral bending tolerance of the head-cervical spine with initial head rotation posture using loads at the occipital condyles and lower neck and describe injuries.

Preliminary Data of Neck Muscle Morphology With Head-Supported Mass in Male and Female Volunteers.

Introduction: This study quantified parameters related to muscle morphology using a group of upright seated female and male volunteers with a head-supported mass.

Materials And Methods: Upright magnetic resonance images (MRIs) were obtained from 23 healthy volunteers after approval from the U.S.

Pelvis-Sacrum-Lumbar Spine Injury Characteristics From Underbody Blast Loading.

Introduction: Combat-related injuries from improvised explosive devices occur commonly to the lower extremity and spine. As the underbody blast impact loading traverses from the seat to pelvis to spine, energy transfer occurs through deformations of the combined pelvis-sacrum-lumbar spine complex, and the time factor plays a role in injury to any of these components. Previous studies have largely ignored the role of the time variable in injuries, injury mechanisms, and warfighter tolerance.

Subclinical respiratory dysfunction and impaired ventilatory adaptation in degenerative cervical myelopathy.

Degenerative cervical myelopathy (DCM) is a debilitating neurological condition characterized by chronic compression of the cervical spinal cord leading to impaired upper and lower limb function. Despite damage to areas of the cervical spinal cord that house the respiratory network, respiratory dysfunction is not a common symptom of DCM. However, DCM may be associated with respiratory dysfunction, and this can affect the ventilatory response to respiratory challenges during emergence from anesthesia, exercise, or pulmonary disease.

Cervical Column and Cord and Column Responses in Whiplash With Stenosis: A Finite Element Modeling Study.

Spine degeneration is a normal aging process. It may lead to stenotic spines that may have implications for pain and quality of life. The diagnosis is based on clinical symptomatology and imaging.

Comparison of Load-Sharing Responses Between Graded Posterior Cervical Foraminotomy and Conventional Fusion Using Finite Element Modeling.

Following the diagnosis of unilateral cervical radiculopathy and need for surgical intervention, anterior cervical diskectomy and fusion (conventional fusion) and posterior cervical foraminotomy are common options. Although patient outcomes may be similar between the two procedures, their biomechanical effects have not been fully compared using a head-to-head approach, particularly, in relation to the amount of facet resection and internal load-sharing between spinal segments and components. The objective of this investigation was to compare load-sharing between conventional fusion and graded foraminotomy facet resections under physiological loading.

Upper cervical spine bone mineral content variations in elderly females.

The purpose of the study was to determine the bone mineral densities (BMDs) of the C1 and C2 vertebrae and discuss their implications for autonomous vehicle environments and vulnerable road users. Using quantitated computed tomography (QCT), the BMDs were obtained at eight regions for the C1 vertebra and seven regions for the C2 vertebra. The spine surgeon author outlined the boundaries of each region, and nine elderly female human cadaver specimens were used.

Finite element modeling of the human cervical spinal cord and its applications: A systematic review.

Background Context: Finite element modeling (FEM) is an established tool to analyze the biomechanics of complex systems. Advances in computational techniques have led to the increasing use of spinal cord FEMs to study cervical spinal cord pathology. There is considerable variability in the creation of cervical spinal cord FEMs and to date there has been no systematic review of the technique.

Open surgical ligation of a thoracic spinal epidural arteriovenous fistula causing thoracic myelopathy: illustrative case.

Background: Spinal epidural arteriovenous fistulas (eAVFs) are rare spinal vascular malformations characterized by an abnormal connection from the paraspinal and paravertebral system to the epidural venous plexus. This contrasts with the more frequently seen spinal dural AVF, where the fistula is entirely intradural. Although endovascular repair is commonly performed for spinal eAVF, few cases require open surgical ligation.

Effect of Cervical Stenosis and Rate of Impact on Risk of Spinal Cord Injury During Whiplash Injury.

Study Design: Finite Element Study.

Objective: To determine the risk of spinal cord injury with pre-existing cervical stenosis during a whiplash injury.

Summary Of Background Data: Patients with cervical spinal stenosis are often cautioned on the potential increased risk of spinal cord injury (SCI) from minor trauma such as rear impact whiplash injuries.

Determinants of spinal cord stress and strain in degenerative cervical myelopathy: a patient-specific finite element study.

Degenerative cervical myelopathy (DCM) is the commonest cause of spinal cord dysfunction in older adults and is characterized by chronic cervical spinal cord compression. Spinal cord stress and strain during neck motion are also known contributors to the pathophysiology of DCM, yet these factors are not routinely assessed for surgical planning. The aim of this study was to measure spinal cord stress/strain in DCM using patient-specific 3D finite element models (FEMs) and determine whether spinal cord compression is the primary determinant of spinal cord stress/strain.

Diffusion-weighted MRI of the spinal cord in cervical spondylotic myelopathy after instrumented fusion.

Introduction: This study investigated tissue diffusion properties within the spinal cord of individuals treated for cervical spondylotic myelopathy (CSM) using post-decompression stabilization hardware. While previous research has indicated the potential of diffusion-weighted MRI (DW-MRI) markers of CSM, the metallic implants often used to stabilize the decompressed spine hamper conventional DW-MRI.

Methods: Utilizing recent developments in DW-MRI metal-artifact suppression technologies, imaging data was acquired from 38 CSM study participants who had undergone instrumented fusion, as well as asymptomatic (non-instrumented) control participants.

Differences in spinal cord biomechanics after laminectomy, laminoplasty, and laminectomy with fusion for degenerative cervical myelopathy.

Objective: Spinal cord stress/strain during neck motion contributes to spinal cord dysfunction in degenerative cervical myelopathy (DCM), yet the effect of surgery on spinal cord biomechanics is unknown. It is expected that motion-preserving and fusion surgeries for DCM will have distinct effects on spinal cord biomechanics. The aim of this study was to compare changes in spinal cord biomechanics after laminectomy with fusion, laminectomy, and laminoplasty using a patient-specific finite element model (FEM) for DCM.

Spinal Cord Stress After Anterior Cervical Diskectomy and Fusion: Results from a Patient-Specific Finite Element Model.

Degenerative cervical myelopathy (DCM) is the commonest cause of cervical spinal cord dysfunction in older adults and is characterized by spinal cord compression and stress during neck motion. Although surgical decompression eliminates static spinal cord compression, cord stress resulting from flexion-extension motion of the spinal column has not been determined for single and multi-level surgical interventions. The effect of surgery on spinal cord stress is expected to change with the number of surgical levels as well as patient-specific anatomy.

Evolving Profile of Acute Spinal Cord Injury Demographics, Outcomes, and Surgical Treatment in North America: Analysis of a Prospective Multi-Center Dataset of 989 Patients.

Changes in demography and injury patterns have altered the profile and outcome of acute spinal cord injury (SCI) over time. This study sought to describe recent trends in epidemiology and early clinical outcomes using the multi-center North American Clinical Trial Network (NACTN) for Spinal Cord Injury Registry. All participants with blunt acute traumatic SCI ( = 782) were grouped into three five-year time intervals from 2005 to 2019 (2005-2009, 2010-2014, and 2015-2019).

A prospective multi-center study comparing the complication profile of modest systemic hypothermia versus normothermia for acute cervical spinal cord injury.

Study Design: Prospective multi-center trial.

Objectives: To characterize the complication profile associated with modest systemic hypothermia after acute cervical SCI in a prospective multi-center study.

Setting: Five trauma centers in the United States.

Surgical Management of Postradiation, Dropped Head Spinal Deformity in Patients with Head and Neck Cancer.

Background: Dropped head syndrome is a morbid condition that affects daily functionality, causing pain and dysphagia and respiratory compromise. Reported causes of dropped head syndrome include neuromuscular disorders, iatrogenic from cervical spine surgery, and idiopathic and postradiation for head and neck cancers. Management of this spinal disorder remains challenging, as the complication rates are high.