Influence of novel design alteration of pedicle screw on pull-out strength: A finite element study.

Background: We conducted a finite element study to assess the effectiveness of a novel pedicle screw design with two alterations in the distal and proximal portions.

Methods: Finite element (FE) models of 24 vertebrae were constructed using computed tomographic data. Pull-out strength of 4 different pedicle screws were compared.

Magnetic Resonance Imaging Evaluation of the Effects of Surgical Invasiveness on Paravertebral Muscles After Muscle-preserving Interlaminar Decompression (MILD).

Study Design: This is a retrospective study.

Objectives: The aim of this study was to determine the extent of damage to the paravertebral muscles after muscle-preserving interlaminar decompression (MILD) using magnetic resonance imaging to evaluate changes in the multifidus muscle (MF).

Summary Of Background Data: Short-term surgical outcomes of MILD for lumbar spinal canal stenosis (LSCS) are satisfactory; however, the extent of damage to the paravertebral muscles after MILD remains unclear.

Dislodgement and gastrointestinal tract penetration of bone cement used for spinal reconstruction after lumbosacral vertebral tumor excision: A case report.

Introduction: Polymethylmethacrylate (PMMA) cement is useful for spinal reconstruction, but can cause complications including new vertebral fractures, neurological disorders and pulmonary embolism. We report a case in PMMA cement used for spinal reconstruction after tumor curettage dislodged and penetrated the gastrointestinal tract.

Diagnoses: The patient was diagnosed with a retroperitoneal extragonadal germ cell tumor at age 27 years.

Three-dimensional morphology and kinematics of the craniovertebral junction in rheumatoid arthritis.

Study Design: A case-series study.

Objectives: To measure the 3-dimensional (3D) morphology and kinematics of the craniovertebral junction (CVJ) using a 3D computed tomography (CT) model; to reveal abnormal patterns and the relationships between pathology and kinematics.

Summary Of Background Data: Evaluations using radiography, 2-dimensional (2D) CT and magnetic resonance imaging have limitations because of the complex 3D structure of the CVJ.

The clinical usefulness of preoperative dynamic MRI to select decompression levels for cervical spondylotic myelopathy.

The study subjects included 54 patients with cervical spondylotic myelopathy who underwent a selective laminoplasty. The patients were divided into three groups according to the number of decompressed levels: two levels, three levels and four or five levels. The number of cord compressions at every intervertebral level was determined in the flexion, neutral, and extension position using a dynamic magnetic resonance imaging (MRI) scan in consideration of both static and dynamic compressions.

Muscle-preserving interlaminar decompression for the lumbar spine: a minimally invasive new procedure for lumbar spinal canal stenosis.

Study Design: Outcomes of muscle-preserving interlaminar decompression (MILD) for the lumbar spine are reported.

Objective: To verify the clinical findings of lumbar MILD.

Summary Of Background Data: A preliminary short-term follow-up study of lumbar MILD demonstrated satisfactory neural recovery and reduced invasiveness.

A new approach to the spectral study of unstable radicals and ions in solution by the use of an inert gas glovebox system: observation and analysis of the infrared spectra of the radical anion and dianion of p-terphenyl.

By using a Fourier-transform infrared spectrometer contained in an inert gas glovebox system (oxygen and water concentrations: <0.1 ppm), high-quality infrared absorption spectra have been observed for the radical anion and dianion of p-terphenyl in tetrahydrofuran solutions. Density functional theory with the B3LYP nonlocal exchange-correlation functional and the 6-311+G** basis set has been used for the calculations of the structures and infrared spectra of the neutral species, radical anion, and dianion of p-terphenyl.

Is posterior spinal cord shifting by extensive posterior decompression clinically significant for multisegmental cervical spondylotic myelopathy?

Study Design: Posterior cervical spinal cord shifting after selective single laminectomy associated with partial laminotomies was compared with that after bilateral open-door laminoplasty between the C3 and C7 levels in relation to the clinical results of each procedure.

Objectives: To investigate the clinical significance of posterior spinal cord shifting after extensive cervical laminoplasty.

Summary Of Background Data: Current techniques used for cervical laminoplasty for multisegmental cervical spondylotic myelopathy (CSM) are consecutively performed between the C3 and C6 or C7 levels with expectation that the spinal cord will shift backward to keep it clear of anterior compression.