C2-C3 Anterior Cervical Fusion: Technical Report.

Study Design: Retrospective review of patients at a university hospital.

Objective: To describe the anterior approach for cervical discectomy and fusion (ACDF) at C2-C3 level and evaluate its suitability for treatment of instability and degenerative disease in this region.

Summary Of Background Data: The anterior approach is commonly used for ACDF in the lower cervical spine but is used less often in the high cervical spine.

Medical science and the Cruelty to Animals Act 1876: A re-examination of anti-vivisectionism in provincial Britain.

The Cruelty to Animals Act 1876 was an important but ambiguous piece of legislation. For researchers it stymied British science, yet ensured that vivisection could continue under certain restrictions. For anti-vivisection protestors it was positive proof of the influence of their campaigns, yet overly deferent to Britain's scientific elite.

Management strategies for acute spinal cord injury: current options and future perspectives.

Purpose Of Review: Spinal cord injury is a devastating acute neurological condition with loss of function and poor long-term prognosis. This review summarizes current management strategies and innovative concepts on the horizon.

Recent Findings: The routine use of steroids in patients with spinal cord injuries has been largely abandoned and considered a 'harmful standard of care'.

Hydrostatic comparison of nonpenetrating titanium clips versus conventional suture for repair of spinal durotomies.

Study Design: Biomechanics.

Objective: To compare the hydrostatic strength of suture and nonpenetrating titanium clip repairs of standard spinal durotomies.

Summary Of Background Data: Dural tears are a frequent complication of spine surgery and can be associated with significant morbidity.

Spinal duraplasty materials and hydrostasis: a biomechanical study: laboratory investigation.

Object: Dural tears are a frequent complication of spinal surgery and contribute to significant morbidity. Occasionally, dural tears cannot be closed primarily and dural patch grafts must be utilized. No data exist on the comparative immediate hydrostatic strength of various patch materials used alone or with a biological adhesive in a spinal dural tear model.

Two-level noncontiguous versus three-level anterior cervical discectomy and fusion: a biomechanical comparison.

Study Design: Biomechanical study.

Objective: To determine biomechanical forces exerted on intermediate and adjacent segments after two- or three-level fusion for treatment of noncontiguous levels.

Summary Of Background Data: Increased motion adjacent to fused spinal segments is postulated to be a driving force in adjacent segment degeneration.

Minimally invasive percutaneous transpedicular screw fixation: increased accuracy and reduced radiation exposure by means of a novel electromagnetic navigation system.

Background: Minimally invasive percutaneous pedicle screw instrumentation methods may increase the need for intraoperative fluoroscopy, resulting in excessive radiation exposure for the patient, surgeon, and support staff. Electromagnetic field (EMF)-based navigation may aid more accurate placement of percutaneous pedicle screws while reducing fluoroscopic exposure. We compared the accuracy, time of insertion, and radiation exposure of EMF with traditional fluoroscopic percutaneous pedicle screw placement.

A population-based study of all-terrain vehicle-related head and spinal injuries.

Background: All-terrain vehicles (ATVs) are inherently unstable and their use results in numerous injuries annually in the United States.

Objective: We evaluated the magnitude of ATV-related head and spinal column injuries in Utah and identified risk factors that might be addressed by preventative measures.

Methods: Four statewide trauma and hospital databases were queried to obtain data on hospital visits by patients with ATV-related neurological injuries in Utah from 2001 to 2005.

The biomechanical contribution of varying posterior constructs following anterior thoracolumbar corpectomy and reconstruction.

Object: Thoracolumbar corpectomy is a procedure commonly required for the treatment of various pathologies involving the vertebral body. Although the biomechanical stability of anterior reconstruction with plating has been studied, the biomechanical contribution of posterior instrumentation to anterior constructs remains unknown. The purpose of this study was to evaluate biomechanical stability after anterior thoracolumbar corpectomy and reconstruction with varying posterior constructs by measuring bending stiffness for the axes of flexion/extension, lateral bending, and axial rotation.

Atlantoaxial transarticular screw fixation: update on technique and outcomes in 269 patients.

Background: Transarticular screw (TAS) fixation is our preferred method for stable internal fixation of the atlantoaxial joint because of its excellent outcomes, versatility, and cost-effectiveness.

Objective: In this article, we update our series of patients who have undergone TAS fixation, with attention to surgical technique, planning, complication avoidance, and anatomic suitability.

Methods: We retrospectively reviewed 269 patients (150 women, 119 men; average age, 52.

Anterior fixation of odontoid fractures in an elderly population.

Object: Fractures of the odontoid process are the most common fractures of the cervical spine in patients over the age of 70 years. The incidence of fracture nonunion in this population has been estimated to be 20-fold greater than that in patients under the age of 50 years if surgical stabilization is not used. Anterior and posterior approaches have both been advocated, with excellent results reported, but surgeons should understand the drawbacks of the various techniques before employing them in clinical practice.

Use of allograft bone for posterior C1-2 fusion.

Object: An iliac crest autograft is the gold standard for bone grafting in posterior atlantoaxial arthrodesis but can be associated with significant donor-site morbidity. Conversely, an allograft has historically performed suboptimally for atlantoaxial arthrodesis as an onlay graft. The authors have modified a bone grafting technique to allow placement of a bicortical iliac crest allograft in an interpositional manner, and they evaluated it as an alternative to an autograft in posterior atlantoaxial arthrodesis.

Local and global subaxial cervical spine biomechanics after single-level fusion or cervical arthroplasty.

An experimental in vitro biomechanical study was conducted on human cadaveric spines to evaluate the motion segment (C4-C5) and global subaxial cervical spine motion after placement of a cervical arthroplasty device (Altia TDI,Amedica, Salt Lake City, UT) as compared to both the intact spine and a single-level fusion. Six specimens (C2-C7) were tested in flexion/extension, lateral bending, and axial rotation under a +/- 1.5 Nm moment with a 100 N axial follower load.

Endovascular balloon angioplasty for treatment of posttraumatic venous sinus thrombosis. Case report.

In severe cases, posttraumatic cerebral sinus thrombosis can result in venous congestion and persistent intracranial hypertension refractory to both conventional medical therapy and surgical decompression. The authors report a unique case of a patient successfully treated with endovascular mechanical thrombolysis using balloon angioplasty for clinically significant posttraumatic venous sinus thrombosis and review the reported treatments for cerebral venous sinus occlusive disease. This 18-year-old man suffered severe closed head injury from a fall while skateboarding.

Oronasopharyngeal chordomas.

Background: Chordomas are rare tumors derived from notochordal remnants. The authors report on a series of three cases of primary familial oronasopharyngeal chordomas treated at our institution.

Methods: A retrospective chart review was completed of the three cases of primary familial oronasopharyngeal chordoma treated at the University of Utah.

Surgical treatment of occipitocervical instability.

Objective: Instability of the occipitocervical junction can be a challenging surgical problem because of the unique anatomic and biomechanical characteristics of this region. We review the causes of instability and the development of surgical techniques to stabilize the occipitocervical junction.

Methods: Occipitocervical instrumentation has advanced significantly, and modern modular screw-based constructs allow for rigid short-segment fixation of unstable elements while providing the stability needed to achieve successful fusion in nearly 100% of patients.

The cervical end of an occipitocervical fusion: a biomechanical evaluation of 3 constructs. Laboratory investigation.

Object: Stabilization with rigid screw/rod fixation is the treatment of choice for craniocervical disorders requiring operative stabilization. The authors compare the relative immediate stiffness for occipital plate fixation in concordance with transarticular screw fixation (TASF), C-1 lateral mass and C-2 pars screw (C1L-C2P), and C-1 lateral mass and C-2 laminar screw (C1L-C2L) constructs, with and without a cross-link.

Methods: Ten intact human cadaveric spines (Oc-C4) were prepared and mounted in a 7-axis spine simulator.

Spinal lipomas: clinical spectrum, embryology, and treatment.

Spinal lipomas, particularly lipomas of the conus medullaris and terminal filum, are the most common form of occult spinal dysraphism and represent a wide spectrum of disease with regard to anatomy, clinical presentation, and treatment options. These lesions, however, are united by a similar embryology and pathological mechanism by which symptoms arise. Recently, the treatment of these lesions has generated much controversy, with some physicians advocating surgical treatment for all patients regardless of symptoms and others proposing that surgery be withheld until symptoms develop.

Spinal radiosurgery for metastatic disease of the spine.

Background: Metastatic tumor in the spinal column is common, causing symptomatic spinal cord compression in approximately 25,000 patients annually. Although surgical treatment of spinal metastases has become safer, less invasive, and more efficacious in recent years, there remains a subset of patients for whom other treatment modalities are needed. Stereotactic radiosurgery, which has long been used in the treatment of intracranial lesions, has recently been applied to the spine and enables the effective treatment of metastatic lesions.

Pigmented villonodular synovitis associated with pathological fracture of the odontoid and atlantoaxial instability. Case report and review of the literature.

Pigmented villonodular synovitis (PVNS) is a proliferative disorder of the synovium with a predisposition for the appendicular skeleton. Rarely PVNS can arise from the spine, where this disorder usually presents with localized or radicular pain secondary to involvement of the posterior elements. The authors report the case of an 82-year-old woman who presented with long-standing neck pain and acute upper-extremity numbness and weakness.

Castleman disease of the spine mimicking a nerve sheath tumor. Case report.

Castleman disease is a rare lymphoproliferative disease of unknown cause. In most cases, afflicted patients present with a mediastinal mass although the disease may manifest in numerous other sites, including intracranially and rarely intraspinally. The authors report on the case of a 19-year-old woman who presented with a large paraspinal mass emanating from the T7-8 neural foramen.

Transient postictal MRI changes in patients with brain tumors may mimic disease progression.

Background: Transient postictal imaging abnormalities in patients with non-tumor-related seizures are well documented and include fluid-attenuated inversion recovery/T2 hyperintensity and parenchymal and meningeal contrast enhancement. In contrast, transient postictal imaging abnormalities in patients with tumor-related seizures have been poorly described. Fifty percent of patients with brain tumors have a seizure during the course of their illness and are often imaged after a seizure or after a change in seizure character or frequency.

Edema is a precursor to central nervous system peritumoral cyst formation.

Despite the common occurrence and frequent clinical effects of peritumoral cysts in the central nervous system (CNS), the mechanism underlying their development and evolution is not understood. Because they commonly produce peritumoral cysts and because serial magnetic resonance imaging (MRI) is obtained in von Hippel-Lindau disease patients, hemangioblastomas provide an opportunity to examine the pathophysiology of CNS peritumoral cyst formation. Serial MRI was correlated with the clinical findings in 16 von Hippel-Lindau disease patients with 22 CNS hemangioblastomas (11 spinal cord; 11 cerebellar) that were associated with the appearance and evolution of peritumoral cysts.

Somatic mutations in VHL germline deletion kindred correlate with mild phenotype.

Generally, von Hippel-Lindau (VHL) disease is caused by a germline mutation of the VHL gene (chromosome 3p), and tumorigenesis is initiated from a "second-hit" deletion. A subset of VHL patients have a germline deletion of the VHL gene, and the molecular events leading to tumorigenesis are not fully understood. To determine the molecular pathogenesis of tumor formation in this setting, we analyzed five central nervous system hemangioblastomas from three patients of a single VHL germline deletion kindred, all displaying mild clinical phenotype.