Kei Watanabe

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STUDY DESIGN A retrospective comparative study. OBJECTIVE To investigate the morphologic features of proximal vertebral fractures in adults following spinal deformity surgery using segmental pedicle screw instrumentation. SUMMARY OF BACKGROUND DATA Fractures above pedicle screw constructs are a clinical problem that warrants further investigation for(More)
The objective of this study was to compare efficacy of cervical surgery for myelopathy in patients > or = 70 and < or = 60 years of age. Forty patients > or = 70 years and 50 patients < or = 60 years of age with MRI and CT proven myelopathy were neurologically assessed using the JOA score. Three operative procedures were performed: anterior spinal fusion,(More)
BACKGROUND There have been no standardized surgical options for severe scoliotic curvatures ≥100°. Halo-gravity traction is a viable option for surgical treatment of severe scoliosis. The aim of this study was to evaluate the efficacy and safety of perioperative halo-gravity traction for scoliosis curves ≥100° with respect to radiographic outcomes and(More)
Osteoporotic fracture in elderly populations is increasing worldwide, but there are few data on the incidence and outcome of osteoporotic fractures, including upper extremity and vertebral fracture, during a certain period in a defined geographic area. The purpose of this study was to determine the incidence of osteoporotic fractures in a particular area:(More)
STUDY DESIGN A comparative study. OBJECTIVE To report a preliminary evaluation of the Scoliosis Research Society Outcomes Instrument (SRS-24) and determine whether differences in baseline scores exist between American and Japanese patients with idiopathic scoliosis. SUMMARY OF BACKGROUND DATA Because the SRS outcomes instrument was primarily introduced(More)
BACKGROUND CONTEXT The use of nonsteroidal anti-inflammatory drugs (NSAIDs) had been implicated as a risk factor for nonunion in spinal fusion. Even with a number of animal and human studies suggesting NSAIDs either delay or inhibit spinal fusion rates, these drugs continue to be used because of demonstrated benefits. Diclofenac sodium is no exception. It(More)
Ossification of the posterior longitudinal ligament of the spine (OPLL) is a common spinal disorder among the elderly that causes myelopathy and radiculopathy. To identify genetic factors for OPLL, we performed a genome-wide association study (GWAS) in ∼8,000 individuals followed by a replication study using an additional ∼7,000 individuals. We identified(More)
STUDY DESIGN Case report. OBJECTIVE To describe an iatrogenic aortic injury by pedicle screw instrumentation during posterior reconstructive surgery of spinal deformity. SUMMARY OF BACKGROUND DATA Iatrogenic major vascular injuries during anterior instrumentation procedures have been reported by several authors, but there have been few reports regarding(More)
To examine how the dorsolateral prefrontal cortex (DLPFC) contributes to the decision process of the saccade direction, we recorded single-neuron activity while two monkeys performed two oculomotor delayed-response (ODR) tasks. In an ordinary ODR task, monkeys were required to make a memory-guided saccade to the cue location after a 3-s delay. In a(More)
Two-dimensional imaging is not adequate for evaluating ossification of the posterior longitudinal ligament (OPLL). This study was designed to evaluate the accuracy of a novel computed tomography (CT)-based three-dimensional (3D) analysis method that we had devised to measure volume changes in OPLL. Twenty OPLL patients (12 male and 8 female; mean age 63.6(More)