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Research paper thumbnail of Does the intraoperative tranexamic acid decrease operative blood loss during posterior spinal fusion for treatment of adolescent idiopathic scoliosis?

Spine, 2012

Retrospective, observational study. To assess the efficacy and safety of tranexamic acid (TXA) in... more Retrospective, observational study. To assess the efficacy and safety of tranexamic acid (TXA) in decreasing operative blood loss and the need for transfusion during posterior spinal fusion for the treatment of idiopathic scoliosis in adolescents. Blood loss associated with spinal surgery is a common potential cause of morbidity and often requires a blood transfusion, which subjects patients to the known risks of blood transfusion including transmission of diseases. Since the 1990s, intraoperative administration of antifibrinolytics has gained popularity. This study assesses the efficacy and safety of TXA in controlling blood loss during posterior spinal fusion for the treatment of idiopathic scoliosis in adolescents at 1 institution. A retrospective comparative analysis of 106 consecutive adolescents undergoing posterior spinal fusion procedures at 1 institution was performed. Patients were analyzed according to treatment group: controls (63) and TXA (43). There were no significant...

Research paper thumbnail of Cause of Idiopathic Scoliosis

Research paper thumbnail of Postoperative behavior of thoracolumbar/lumbar curve and coronal balance after posterior thoracic fusion for Lenke 1C and 2C adolescent idiopathic scoliosis

Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association, 2015

Controversy still exists around surgical strategies for Lenke type 1C and 2C curves with primary ... more Controversy still exists around surgical strategies for Lenke type 1C and 2C curves with primary thoracic and compensatory lumbar curves in adolescent idiopathic scoliosis (AIS). The benefit of selective thoracic fusion (STF) for these curve types is spontaneous lumbar curve correction while saving more mobile lumbar segments. However, a risk of postoperative coronal decompensation after STF has also been reported. This multicenter retrospective study was conducted to evaluate postoperative behavior of thoracolumbar/lumbar (TLL) curve and coronal balance after posterior thoracic fusion for Lenke 1C and 2C AIS. Twenty-four Lenke 1C and 2C AIS patients who underwent posterior thoracic fusion were included. The mean age of patients was 15.7 years old at time of surgery. Constructs used for surgery in all cases were pedicle screw constructs ending at L3 or above. Radiographic measurements were performed on Cobb angles of the main thoracic and TLL curves and coronal balance. Factors rela...

Research paper thumbnail of Lumbosacral fixation using sacroiliac buttress screws: a modification to the Jackson technique with intrasacral rods

Scoliosis, 2014

Background: The use of intrasacral rods has been previously reported for posterior lumbosacral fi... more Background: The use of intrasacral rods has been previously reported for posterior lumbosacral fixation. However, problems associated with this technique include poor stability of the rod in the sacrum, difficulty in contouring the rod to fit the lateral sacral mass, and the complicated assembly procedure for the rod and pedicle screws in the thoracolumbar segments after insertion of the rod into the sacrum. Methods: We used a screw with a polyaxial head instead of an intrasacral rod, which was inserted into the lateral sacral mass and assembled to the rod connected cephalad to pedicle screws. The dorsal side of the screw was stabilized by the sacral subchondral bone at the sacroiliac joint with iliac buttress coverage, and the tip of the screw was anchored by the sacral cortex. Results: Three different cases were used to illustrate lumbosacral fixation using intrasacral screws as an anchor for the spinal instrumentation. Effective resistance of flexural bending moment and fusion were achieved in these patients at the lumbosacral level. Conclusions: An intrasacral screw can be stabilized by subchondral bone with iliac buttress coverage at the dorsal and ventral sacral cortex. Posterior spinal fusion with this screw technique enables easier assembly of the instrumentation and presents better stabilization than that provided by the previously reported intrasacral rod technique for correction and fusion of thoracolumbar kyphoscoliosis.

Research paper thumbnail of Experimental scoliosis in melatonin-deficient C57BL/6J mice without pinealectomy

Journal of Pineal Research, 2006

Research paper thumbnail of Does the intraoperative tranexamic acid decrease operative blood loss during posterior spinal fusion for treatment of adolescent idiopathic scoliosis?

Spine, 2012

Retrospective, observational study. To assess the efficacy and safety of tranexamic acid (TXA) in... more Retrospective, observational study. To assess the efficacy and safety of tranexamic acid (TXA) in decreasing operative blood loss and the need for transfusion during posterior spinal fusion for the treatment of idiopathic scoliosis in adolescents. Blood loss associated with spinal surgery is a common potential cause of morbidity and often requires a blood transfusion, which subjects patients to the known risks of blood transfusion including transmission of diseases. Since the 1990s, intraoperative administration of antifibrinolytics has gained popularity. This study assesses the efficacy and safety of TXA in controlling blood loss during posterior spinal fusion for the treatment of idiopathic scoliosis in adolescents at 1 institution. A retrospective comparative analysis of 106 consecutive adolescents undergoing posterior spinal fusion procedures at 1 institution was performed. Patients were analyzed according to treatment group: controls (63) and TXA (43). There were no significant...

Research paper thumbnail of Cause of Idiopathic Scoliosis

Research paper thumbnail of Postoperative behavior of thoracolumbar/lumbar curve and coronal balance after posterior thoracic fusion for Lenke 1C and 2C adolescent idiopathic scoliosis

Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association, 2015

Controversy still exists around surgical strategies for Lenke type 1C and 2C curves with primary ... more Controversy still exists around surgical strategies for Lenke type 1C and 2C curves with primary thoracic and compensatory lumbar curves in adolescent idiopathic scoliosis (AIS). The benefit of selective thoracic fusion (STF) for these curve types is spontaneous lumbar curve correction while saving more mobile lumbar segments. However, a risk of postoperative coronal decompensation after STF has also been reported. This multicenter retrospective study was conducted to evaluate postoperative behavior of thoracolumbar/lumbar (TLL) curve and coronal balance after posterior thoracic fusion for Lenke 1C and 2C AIS. Twenty-four Lenke 1C and 2C AIS patients who underwent posterior thoracic fusion were included. The mean age of patients was 15.7 years old at time of surgery. Constructs used for surgery in all cases were pedicle screw constructs ending at L3 or above. Radiographic measurements were performed on Cobb angles of the main thoracic and TLL curves and coronal balance. Factors rela...

Research paper thumbnail of Lumbosacral fixation using sacroiliac buttress screws: a modification to the Jackson technique with intrasacral rods

Scoliosis, 2014

Background: The use of intrasacral rods has been previously reported for posterior lumbosacral fi... more Background: The use of intrasacral rods has been previously reported for posterior lumbosacral fixation. However, problems associated with this technique include poor stability of the rod in the sacrum, difficulty in contouring the rod to fit the lateral sacral mass, and the complicated assembly procedure for the rod and pedicle screws in the thoracolumbar segments after insertion of the rod into the sacrum. Methods: We used a screw with a polyaxial head instead of an intrasacral rod, which was inserted into the lateral sacral mass and assembled to the rod connected cephalad to pedicle screws. The dorsal side of the screw was stabilized by the sacral subchondral bone at the sacroiliac joint with iliac buttress coverage, and the tip of the screw was anchored by the sacral cortex. Results: Three different cases were used to illustrate lumbosacral fixation using intrasacral screws as an anchor for the spinal instrumentation. Effective resistance of flexural bending moment and fusion were achieved in these patients at the lumbosacral level. Conclusions: An intrasacral screw can be stabilized by subchondral bone with iliac buttress coverage at the dorsal and ventral sacral cortex. Posterior spinal fusion with this screw technique enables easier assembly of the instrumentation and presents better stabilization than that provided by the previously reported intrasacral rod technique for correction and fusion of thoracolumbar kyphoscoliosis.

Research paper thumbnail of Experimental scoliosis in melatonin-deficient C57BL/6J mice without pinealectomy

Journal of Pineal Research, 2006

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