• The Journal of Korean Orthopaedic Ultrasound Society
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• v.5 no.1
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• pp.15-21
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• 2012

Primary radial nerve palsy occurs in association with approximately 10% of humerus shaft fractures. Secondary radial nerve palsy, which is iatrogenic, occurs in association with approximately 10% to 20% of humerus shaft fractures. Whether the radial nerve palsy is caused primarily by the fracture or secondarily by the surgery, it is necessary to determine whether the radial nerve is being disrupted or compressed by the surrounding structures. This evaluation will dictate whether to await natural recovery or to perform surgical exploration. The current authors report one case of primary radial nerve palsy, due to the humerus fracture, and one case of secondary radial nerve palsy, associated with the osteosynthesis procedure. In both patients, the radial nerve was assessed for anatomical integrity with ultrasonography. Nerve disruption was found in one patient, and a sural nerve graft was performed. Nerve adhesion was found in the other patient, and neurolysis was performed. In both cases, the clinical results were satisfactory. This report focuses on the usefulness of ultrasonography in radial nerve assessment in patients with radial nerve palsy.

• Clinics in Shoulder and Elbow
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• v.23 no.3
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• pp.131-135
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• 2020

Background: Resection of the radial head is a surgical indication for comminuted radial head fracture in which internal fixation is inaccessible. Some complications from the surgery can alter the function of the patient's elbow. The objective of this study was to assess functional outcome of the elbow after resection of the radial head. Methods: A retrospective longitudinal study was performed with patients who underwent radial head resection between 2008 and 2018. Elbow function was assessed by the Mayo Elbow Performance Index (MEPI) for 11 patients comprising three women and eight men. The mean follow-up was 47.6 months. The mean age was 41±10.3 years. Results: Nine patients had a stable and painless elbow. The mean extension-flexion arc was 97.73°±16.03°. The mean values of pronation and supination were 76.8° and 74.5°, respectively. The mean MEPI score was 83.2 points, and restoration of overall function was achieved in 81% of the cases. Poor function was noted in one in 10 that presented with a terrible triad. Conclusions: Resection of the radial head restored elbow functionality at a rate of 81%, which was a good outcome for patients.

• Journal of Veterinary Clinics
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• v.18 no.2
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• pp.156-159
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• 2001

A 6-year-old male mongrel dog with a 7-month history of ulnar-radial nonunion fracture was treated with implantation of recombinant human bone morphogenetic protein-2 (rhBMP-2). The dog had received surgical correction three times prior to the admission but radiography of the affected limb revealed a typical figure of nonunion fracture. Glossly, the fractured ends were sclerotic and the area between the ends was filled with fibrous tissue. After debridement the shaft was fixed by an 10-hole plate. rhBMP-2 at a total dose of 256 micrograms was implanted with a synthetic carrier into the 10-mm defect formed by the debridement. Callus formation responding to rhBMP-2 was radiographically observed at 4 weeks after implantation and the defect bridged both fracture ends by 8 weeks after implantation. The plate was removed at 12 months after implantation. Any complications were not observed for 5 months after removal of the plate.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.2
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• pp.5-13
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• 1995

Various techniques to measure fracture toughness which is an important parameter to predict fracture behavious of structural materials have been reported. Among these mathods, this paper describes the micro-Vickers indentation crack method to estimate the fracture toughness of some WC-Co composites. Two indentation crack patterns (such as radial-median cracks (orhalf-penny cracks) and Palmqvist cracks generated during indentation) are referred precisely. The fracture toughness of WC-4.7wt%Co, WC-6wr%Co and WE-9wr%Co composites were estimated by using some equations given by Shetty et al., Nihara et al. in this study. We show the reliability of indentation method by comparing the results with those from literatures. The appropriate equation to estimate the fracture toughness in the case of WC-Co composite is given. In addition, some technical informations in terms of the crack length by indentation in estimating the existence of the surface residual stress that prevents to obtain an accurate fracture toughness are presented.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.140-145
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• 2011

Purpose: Installing a radial head prosthesis has developed into a reliable procedure to replace the native radial head for treating unreconstructible radial head fracture when this is associated with an unstable elbow or forearm. A variety of implants have been developed and these are now commercially available. This article reviews the literature related to the indications, the available implants and the surgical techniques of radial head replacement arthroplasty. Materials and Methods: The main indication for a metallic radial head prosthesis is a comminuted fracture that is not amenable to reconstruction, and particularly if it is associated with complex elbow injuries. Excision of the radial head should be avoided in the presence of combined injured ligaments or interosseous membrane injury. Three different implants are available in Korea, including the bipolar, press fit monopolar and loose fit monopolar radial head prostheses. A primary technical goal of radial head arthroplasty is the insertion of an implant that closely replicates the native radial head. The major pitfall when using a metallic radial head prosthesis is the insertion of a longer implant, which results in overstuffing of the radiocapitellar joint. Results and Conclusion: Satisfactory clinical results can be anticipated when a radial head prosthesis is used for the correct indications and when a systemic approach is undertaken to ensure proper sizing. For the future studies, we need data regarding the long term outcomes and comparison of the various types of prostheses.

• Journal of the Korean Society of Safety
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• v.11 no.4
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• pp.3-9
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• 1996

In this study, comparison of theoretical solutions with experimental results is examined through fracture conditions for the case of float glasses subjected static loading. The range of fracture generation limits and critical penetration energies are solved according to the impactor mass under the high velocity, and analytical method of fracture strength and penetration strength are presented. Also, fracture patterns are investigated according to impact velocities. The results obtained from this study are as follows ; 1) Radial cracks are generated from the loading point regardless of plate thickness in the case of the plate subjected to the static loading. In the case of high-speed impact, dimensions of ring cracks become to smaller and length of radial cracks becomes shorter with the rapidity of impact velocity. 2) Kinetic change volume of collision after/before is constant regardless of velocities over the range of critical penetration velocity. 3) Although the same impact energy is working, the critical penetration energy is increased with the shorter of impactor mass. 4) Although the same impact energy is working, the penetration fracture of lighter Impactor mass is generated more than that of heavier impactor mass, and the impulse of lighter impacter mass appear more than that of heavier impactor mass. Therefore, the penetration fracture in the case of greater impulse is generated earlier regardless of the of the dimensions of Impact loading.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.3
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• pp.199-205
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• 1994

The fracture characteristics and tool life of ceramics and WC, CBN cutting tool when turning heat treated steel STD11($H_RC$ 60) were investigated experimentally to clarify the machinability and optimum tool materials in cutting of difficult-to-cut material with high hardness. Forthermore, the behaviors of the tool wear and failure were examined with regard to cutting force. The hardened steel wore the cutting tool edge rapidily and increased the cutting forces, especially radial force. The tool was worn by the abrasive action. Flank Weat of $Al_2O_3-TiC$ ceramic and WC tool become relatively large and CBN & $Al_2O_3$, ceramic tool had a long life among the tool materials tested. The tool fracture patterns were just like minor cutting wear, flank wear, crater wear, notch wear, chipping. Flank wear rate was accelerated by occurrence of chipping. During the proceeding of machining, it was possible to foresee the catastrophic fracture of tool by abrupt increase of radial force.

• Clinics in Shoulder and Elbow
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• v.10 no.1
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• pp.84-91
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• 2007

Purpose: The aim of this study was to report seven cases of metallic radial head prosthesis and present the limit of use in Korea. Materials and Methods: Metallic radial head arthroplasty was performed on 7 patients between April 2006 and December 2006, who had complex elbow injury including comminuted radial head fracture. Indication, operative findings and outcome were assessed. Availability and payment of implant were investigated. Results: All of the patients had more than one associated injury including coronoid fracture, olecranoan fracture, and ligament ruptures. According to Mason classification, there were three type III and four type IV fractures. All radial head fractures were too comminuted to reconstruct. There were two excellent results, four good, and one poor, as graded by Mayo score. There were no patient with instability and implant related complications. Insufficient supply of implant did not enable to do scheduled surgery in 2 cases. Current medical insurance did not cover charge for radial prosthesis, five patients could not help paying for that by themselves. Conclusion: Metallic radial head implants are useful when the radial head cannot be repaired reliably. Preoperative preparing and coverage by medical insurance based on appropriate indication are helpful for decision for a treatment option.

• Transactions of Materials Processing
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• v.12 no.3
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• pp.228-235
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• 2003

In this paper, the workability of flange in the radial extrusion is analyzed in terms of the deformation pattern, the punch load and the forming limit by using simulation and experiment. A single action pressing is applied to both simulation and experiment. The analysis in this study is focused on the transient extrusion into the gap in radial direction with various gap heights and die corner radius. Based on the surface strains where surface cracking occurs, the forming patterns and strain-fracture relationships in producing radially extruded flange are obtained.

• Journal of Veterinary Clinics
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• v.33 no.2
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• pp.135-137
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• 2016

A 6-month-old, weighing 2.8 kg, female, domestic short-haired cat presented with open fracture at right distal radius about a month ago. Based on radiological findings, hyperplasia at the right radioulna and left humerus was found. Results of the cytological examination were inflammatory reaction and reactive osteoblast. Distal radial ostectomy proceeded with necrotic bone debridement. Three weeks after operation, the radial bone lysis was seen on radiograph but clinical condition improved. Hyperplasia at the right radioulna and left humerus was dissolved. Two months after operation, she can use her both forelimbs despite right elbow have been diagnosed as arthrosclerosis because of periosteal reaction. Six months after operation, clinical symptoms of limbs were not detected. In this case, open fracture was treated through delayed surgical debridement procedure, therefore hematogenous osteomyelitis occurs at another forelimb. The longer a wound remains open, the more likely it is that infection will develop. The infection can occur to fracture bone and seed from hematogenous spread to another normal bone. In conclusion, when open fracture occurs, early antibiotic treatment and urgent surgical intervention are recommended.