• Journal of the Korean Orthopaedic Association
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• v.52 no.1
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• pp.83-91
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• 2017

Purpose: To investigate the clinical outcomes of distal hook augmentation using a pedicle screw in thoracolumbar fusion in elderly patients. Materials and Methods: This retrospective multicenter study recruited 20 patients aged 65 years or older, who underwent anterior support and long level posterior fusion in the thoracolumbar junction with a follow-up of one year. To assess the effect of distal hook augmentation, the patients were divided into two groups; the pedicle screw with hook group (PH group, n=10) and the pedicle screw alone group (PA group, n=10). Results: The average age was 72.4 years (65-83 years). The average fusion segment was 4.6 segments (3-6 segments). There were no significant differences in age, sex, causative diseases, bone mineral density of lumbar and proximal femur, number of patients with osteoporosis, and number of fused segments between the two groups (p≥0.05). At 1 year follow-up after surgery, parameters related with distal screw pullout were significantly worse in the PA group. No patients in the PH group had distal screw pullout. However, six patients (60%, 6/10) in the PA group had distal screw pullout. There were no significant differences in the progression of distal junctional kyphosis between the two groups. Conclusion: Distal hook augmentation is an effective procedure in protecting distal pedicle screws against the pullout when long level thoracolumbar fusion was performed in elderly patients aged 65 years or older.

• 대한두경부종양학회:학술대회논문집
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• 1991.11a
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• pp.36-36
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• 1991

• The Journal of the Korean dental association
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• v.4 no.1
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• pp.19-24
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• 1963

• The Journal of the Korean dental association
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• v.3 no.1
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• pp.40-43
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• 1961

• Journal of Sericultural and Entomological Science
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• v.33 no.2
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• pp.68-71
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• 1991

Mulberry cuttings from shoots of Shinkwangppong(Morus bombycis koidz.) had been callused in vermiculite separately at 15, 20, 25 and 30$^{\circ}C$ for 15 days before transplanting them in greenhouse to make clear the effect of temperature on root formation and growth is as follow. The buds of cuttings started sprouting in 4 and 6 days of callusing at 30 and 25$^{\circ}C$, respectively, reaching 100% budding in 10 and 15 days of callusing. Budding was delayed, however, at low temperature, showing 86% and 92% at 15 and 20$^{\circ}C$, respectively, in 15 days. Rooting from the cuttings was also accelerated at high temperature, showing 97-100% rooting at 25$^{\circ}C$ and 30$^{\circ}C$, in 15 days of callusing but no more than 93% at low temperature even in 35 days. Although high temperature increased root number and length after 15 days in callusing, no differences showed in the number and the weight at more than 20$^{\circ}C$ in 35 days of cuttings.

• Journal of Sericultural and Entomological Science
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• v.33 no.2
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• pp.63-67
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• 1991

Various concentrations of ${\alpha}$-naphthalence acetic acid(NAA) as a root-promoting substance were tested in hardwood cutting of the mulberry(Morus bombycis Koidz., cultivar : Shinkwangppong) to make clear the callusing effect on the budding and root growth. Budding and shoot growth of cuttings were delayed at high concentrations of NAA within 10 days of callusing. Especially more severe is it at higher than 50ppm. More than 93% of them, however, budded in two weeks when callused at less than 100ppm NAA. Although rooting was accelerated at high concentration of NAA from the bigining of cutting, after that, rooting percentage increased to reach 100% in 35 days of cutting in any concentration except 150ppm with relatively low rooting. Root growth was utmostly accelerated at 50ppm NAA to show the highest amount in number, length and weight of roots per cutting although high concentration of it decreased mean root length.

• Applied Microscopy
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• v.31 no.4
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• pp.307-314
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• 2001

Safflower (Carthamus tinctorius L.) is a thistle-like annual plant mainly grown in dry hot climates as an oilseed or birdseed. Traditionally, the oil has mainly been sold in the health food market because it is unsaturated having high linoleic and oleic acid levels. With increased health consciousness in recent years, the oil quality has become a more general health issue. This study was designed to understand whether safflower seed powder has positive effects on the fracture healing in rats. Simple transverse fracture of rat fibula was made with a rotating diamond disc saw. The histologic changes of rats were observed with a scanning electron microscope. The fractured fibulae showed a complete fusion at the fracture site in the 4th to 5th week after a simple transverse fracture. Administration of safflower seed powder facilitated the speed of histologic changes without affecting qualitative changes. These results suggest that safflower seed powder nay have substances that help the fracture healing process.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.11
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• pp.943-950
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• 2016

The purpose of this study was to evaluate and compare by finite element analysis the biomechanical performance, in terms of cervical stand-alone cage screw insert angle (Type 3 - 5: 2 Screws) and screw arrangement (Type 6 and 7: 3 Screws / Type 8 and 9: 4 Screws), and the range of motion (ROM) of traditional anterior cervical discectomy of a fusion device (Type 1: Cage / Type 2: Cage + ACP). Our study suggests that the biomechanical behavior of a postoperative cervical spine could indeed be influenced by design features, such as screw angle and number of screws. In particular, ROM and the risk of subsidence were more sensitive during extension about type 5 (Insert Angle $20^{\circ}$). Our study also suggested that the number of screw asymmetries between up and down for type 6 and 7 could result in differences in the risk of screw fracture manifesting in different clinical aspects.

• Journal of Yeungnam Medical Science
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• v.7 no.1
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• pp.203-210
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• 1990

This is a case report of correction of malunioned maxilla after traffic accident by Le Fort I osteotomy and posterior segmental osteotomy. By this procedure, authors obtained the following results. 1. The malinioned maxilla after traffic accident which had anterior crossbite, posterior open bite and scissor's bite were corrected by Le Fort I osteotomy and posterior segmental osteotomy. 2. No postoperative infection and specific complication were seen in this case. 3. Postoperative intermaxillary fixation was maintained for 8 weeks. And then, the patient could open his mouth in normal range after a week of intermaxillary fixation removal. 4. For rigid fixation and reducing relapse, the osteotomized maxilla was fixed with miniplates.

• Composites Research
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• v.34 no.3
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• pp.186-191
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• 2021

The lumbar spinal fusion is a treatment performed to restore the stability of the degenerated lumbar. In this study, the intervertebral discs between two or more segments are removed and a bone graft is inserted to harden the segments. The pedicle screw system is inserted to vertebral bodies to fix two or more segments so that they can be firmly fused. In this study, a total of 7 patient-specific lumbar finite element models were created and pedicle screw systems were installed. The connecting rods made of titanium and CFR-PEEK was inserted to the generated models. Finite element analysis was conducted for four representative spine behaviors and statistical analysis was performed to investigate the biomechanical effects by the material properties of connecting rods. The intradiscal pressure of adjacent segments and the range of motion of the joints of each segment were investigated. In the subjects who used CFR-PEEK instead of Ti for connecting rods, the intradiscal pressure of adjacent segments tend to decrease and the range of motion of each segment tend to increase. However, no statistically significant difference in tendency was observed under all loading conditions.