• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.160-167
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• 2005

Purpose : Distal femur and proximal tibia are the common sites affected by giant cell tumor of bone. There are a variety of treatment modality including wide excision and intralesional curettage. We evaluated the local recurrence rates and the post-operative functional scores of giant cell tumors around knee joint and investigated the identification of possible prognostic factors for recurrence. Materials and Methods: We reviewed 41 patients pathologically confirmed as giant cell tumors around knee joint that have undergone intralesional curettage using high-speed burr and methylmethacrylate. We evaluated the recurrence rate and post-surgical functional score and possible prognostic factors for recurrence, such as, gender, age, tumor location, size, subchondral invasion, intra-articular invasion and the Campanacci Grades. Mean follow up period was 50 (12-122) months. Results: The recurrence rate was 17% and mean recurrence onset was 10 months postoperatively. According to Musculoskeletal Tumor Society (MSTS) functional evaluation system, the average score was 27.8(93%) and 78% had excellent function. According to our study, suspected prognostic factors revealed not significant for recurrence. Conclusion: We found no significant recurrence related factors. Intralesional excision with high-sped burring and PMMA provides a low recurrence rate, similar to others in the literature, and good functional scores.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.1
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• pp.45-50
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• 2011

Hot-Press-Forming (HPF), an advanced sheet metal forming method using stamping at a high temperature of about $900^{\circ}C$ and quenching in an internally cooled die set, is one of the most successful forming process in producing crash-resistant parts such as pillars and bumpers with complex shape, ultrahigh strength, and minimum springback. To optimize conditions of a forming quality in HPF process and secure a safe product without any failures, such as fractures and wrinkling, the simulations based on the coupled thermo-mechanical analysis for a hot-press-formed lower control arm are applied with Taguchi's orthogonal array experiment. Three factor variables - the friction coefficient, blank shape, and hole location for burring - are selected to be optimized. The most effective condition of a forming quality for a hot-press-formed lower control arm is suggested. The simulation results are confirmed with experimental ones.

• Archives of Craniofacial Surgery
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• v.21 no.1
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• pp.73-76
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• 2020

Cranial implant removal is recommended if implants become exposed owing to scalp necrosis after cranioplasty. However, it carries the risk of extensive bleeding, and the resultant cranial defects can cause both aesthetic and functional problems. We present a case of a scalp defect exposing a cranial prosthetic implant that was reconstructed with a local flap and salvaged using an indwelling antibiotic irrigation system. A 73-year-old man presented with scalp necrosis after undergoing cranioplasty due to intracranial hemorrhage. The cranial implant was exposed through the scalp defect. Methicillin-resistant Staphylococcus aureus was detected in the culture from the open wound. After debridement of the necrotic tissue and burring of the superficial layer of the implant, a transposition flap was used to cover the defect and an indwelling antibiotic irrigation system was installed. Continuous irrigation with vancomycin was conducted for 5 days, and intravenous vancomycin was continued for 4 weeks. The flap was in good condition at 4 months postoperatively, with no infection. The convex contour of the scalp was well maintained. The patient's neurological status was stable. Exposed cranial implants can be salvaged with continuous antibiotic irrigation as an alternative to implant removal; thus, the risk of bleeding and possible disfigurement may be avoided.

• Journal of Mechanical Science and Technology
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• v.19 no.4
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• pp.968-975
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• 2005

The shearing process for the sheet metal is normally used in the precision elements such as semi-conductor components. In these precision elements, the burr formation brings a bad effect on the system assembly and demands the additional de-burring process, so this imposes high cost on manufacturing. In this paper, we have developed the in-situ auto-aligning precision meso-punching system to investigate the burr formation mechanism and ultimately minimize burr. Firstly, we introduced the punch-die contact sensing method to align the punch and the die at initial state prior to the punching process. Secondly, by using the low-price semi-con­ductor laser, burr formed on the edges is measured intermittently during the punching process. We could, finally, make burr on the sheet metal uniformized and minimized by controlling of the precision X - Y table, $1\;{\mu}m$ resolution, and measuring burr height by semiconductor laser. Experimental results show the validity of our system for pursuing the burr-free punched elements.

• Archives of Craniofacial Surgery
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• v.25 no.1
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• pp.38-43
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• 2024

Cherubism is a rare fibro-osseous condition characterized by bilateral expansion of the mandible and maxilla. Due to its rarity, treatment guidelines for cherubism have not been clearly established. Observation without surgical intervention is typically recommended, as cherubism often regresses spontaneously after puberty. However, a surgical intervention may be necessary if aggressive lesions lead to severe complications. In this report, we present a case involving surgical management of cherubism that did not spontaneously regress until early adulthood. An 18-year-old man was diagnosed with cherubism, presenting characteristic upward-looking eyes and a swollen face. He strongly desired surgical management. Gross contouring of the mandible was performed using an osteotome. Subsequently, delicate contouring was performed by bone burring and curettage. The remaining multiple locular bony defects were filled with demineralized bone matrix. No major complications, including infection and hematoma, occurred during the 8-month follow-up period. The facial contour remained stable without the aggravation of cherubism. The patient was satisfied with the cosmetic results. Considering that cherubism is a rare disease globally, with few reported cases in Korea, and that treatment guidelines are not clearly established, we anticipate that the results of this case will contribute to the development of future protocols for treating cherubism.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.1
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• pp.15-22
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• 2006

Purpose: This study was designed to investigate the clinical and oncological results of giant cell tumor, treated with electrocautery as an adjuvant. Materials and Methods: We evaluated 47 giant cell tumors treated in both institution from 1989 to 2004, retrospectively. We treated all 47 cases with intralesional curettage and speed burring and followed electrocautery as an local adjuvant. Results: The mean follow up periods was 44 months and ranged from 12 to 180 months. The local recurrence occurred in 8 patients (17%) and one case lung metastasis was found. There was one case complication (septic knee) associated with electrocautery as an adjuvant. Conclusions: We thought electrocautery was feasible adjuvant treatment method of giant cell tumor, because it is very convenient technique, and the local recurrence rate was similar to any other methods.

• Archives of Plastic Surgery
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• v.33 no.3
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• pp.371-375
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• 2006

Frontometaphyseal dysplasia is a rare genetic syndrome first described by Gorlin and Cohen in 1969. This disease affects the skeletal system and connective tissue, and could be characterized by hyperostosis of the skull, prominence of supraorbital ridges, additional skeletal and extraskeletal abnormalities. It is believed that the condition is an X-linked dominant trait with severe manifextations in males and extreme variability in females.We described a case of 15-year-old boy manifested a pronounced supraorbital ridge associated with exorbitism. He also had bilateral progressive hearing deficit, thoracic spine scoliosis, chest wall deformity, bilateral maxillary sinusitis and both 5th finger arachnodactyly.The patient underwent a fronto-temporo-orbital cranioplasty through a coronal incision. The frontal bone including supraorbital region, orbital lateral rim and temporal bone were extensively contoured with burr. And then, burring of the medial aspect of lateral orbital wall was made to increase both orbital volume for correction of exorbitism. Postoperative results show well corrected prominent supraorbital ridge, hyperostosis of frontotemporal bone and exorbitism. The patient was satisfied with the improved appearance. No recurrence occurred during the 6 months of follow-up period. We report this case as it shows esthetically good result without any complication.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.10
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• pp.1303-1310
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• 2001

In order to be applicable to the combustion modelling of stratified charged combustion like that of - lean burn and GDI engine, the correlations of laminar burring velocities fur several hydrocarbon fuels and methanol are needed over a wide range of equivalence ratio, pressure and temperature. In this study, these correlations are modeled in the 1311owing form based on the experimental and Muller\`s modeling results for several fuels, where $\alpha$, ξ, and ξ are functions of pressure and temperature, $S_{L}$ =$\alpha$ exp[-ξ($\Phi$-$\Phi$$_{m}$)$^{2}$ -exp {-ζ($\Phi$-$\Phi$$_{m}$)}-ζ($\Phi$-$\Phi$$_{m}$)]. By using the results calculated by PREMIX code with Sloane\`s detailed chemical reaction mechanism for propane, it is verified that the coefficients of the abode modeling can be determined by considering laminar burning velocity data only in a range of equivalence ratio less than $\Phi$$_{m}$. Therefore, Muller\`s modeling results can be adopted leer modeling of the pressure and temperature dependency. Compared with the results of the existing Keck'and Gulder's models, those of the present one showed the good agreement of the recent experimental data, especially in the range of lean and rich sides.s.des.s.

• Journal of Korean Foot and Ankle Society
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• v.17 no.4
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• pp.288-293
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• 2013

Purpose: Number of arthroscopic surgery is gradually increasing with development of its equipment and technique. Arthroscopic ankle surgery performed with the traction device has various complications and need more time for preparation. We investigated whether the complication rate increased when surgery was performed without the traction device, and compared the complication rate of arthroscopic surgery with the traction device. Materials and Methods: From January 2009 to June 2012, arthroscopic ankle surgery was performed without the traction device in four hundred eleven cases. There were two hundred sixty-one males and one hundred fifty females. The average age at operation was 35 years (range, 17-56), and the average follow up period was 28 months (range, 12-41). Postoperative symptoms and complications were checked. Results: There were difficulties performing arthroscopic surgery without the traction device in five cases with severe traumatic osteoarthritis. However, after burring and shaving, we had enough space to work on. Superficial peroneal nerve symptom was found in two cases, grooving of talus was found in 11, and saphenous vein injury was found in five. Since preparing for the traction device was unnecessary, we were able to save time with the mean duration of surgery of 50 minutes (range, 30-120). Conclusion: With only manual traction, we could explore the entire ankle joint without damage on cartilage. Yet, skilled arthroscopic technique will be necessary for arthroscopic surgery without the traction device.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.512-515
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• 2011

Purpose: Osteoma is one of the common benign tumors of the skull vault and facial skeleton. Although most of the osteomas cause no symptoms, forehead osteomas may lead to facial disfigurement. Osteoma usually happens in solitary lesion and multiple osteomas which don't combine with syndrome are very rare. We report an experience of treatment of non-syndromic multiple osteomas in the skull. Methods: A 54-year-old female patient visited due to the multiple palpable hard masses on her forehead in 2010. In 2002 of her first visit, masses started to appear on her forehead and she was diagnosed as the osteoma by excisional biopsy. She visited again because the mass size and number increased. In preoperative CT scanning, there were above 160 of osteomas, so surgery was planned. Enterogastroduodenoscopy and colonoscopy was conducted to rule out Gardener's syndrome, however there was no abnormality such as multiple polyposis. Results: Under general anesthesia, coronal approach was conducted. There were numerous osteomas in frontal and parietal bone. The multiple osteomas were removed by burring and the patient recovered without any postoperative complications. Conclusion: Multiple osteomas in the skull were rarely reported, although it can accompanied with Gardener's syndrome. We report a case of non-syndromic multiple osteomas in skull vault.