• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2304-2311
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• 2021

The dislocation density in strain-hardened Alloy 690 was analyzed using scanning transmission electron microscopy (STEM) to study the relationship between the local plastic strain and susceptibility to primary water stress corrosion cracking (PWSCC) in nuclear power plants. The test material was cold-rolled at various thickness reduction ratios from 10% to 40% to simulate the strain-hardening condition of plant components. The dislocation densities were measured at grain boundaries (GB) and in grain interiors of strain-hardened specimens from STEM images. The dislocation density in the grain interior monotonically increased as the strain-hardening proceeded, while the dislocation density at the GB increased with strain-hardening up to 20% but slightly decreases upon further deformation to 40%. The decreased dislocation density at the GB was attributed to the formation of deformation twins. After the PWSCC growth test of strain-hardened Alloy 690, the fraction of intergranular (IG) fracture was obtained from fractography. In contrast to the change in the dislocation density with strain-hardening, the fraction of IG fracture increased remarkably when strain-hardened over 20%. From the results, it was suggested that the PWSCC growth behavior of strain-hardened Alloy 690 not only depends on the dislocation density, but also on the microstructural defects at the GB.

• Journal of Korean Foot and Ankle Society
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• v.21 no.2
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• pp.70-74
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• 2017

Fractures and fracture-dislocations of the ankle are caused by a variety of mechanisms. In addition to fractures, injuries of soft tissue, such as ligaments, tendons, nerves, and muscles may also occur. Among these, a tibialis posterior tendon injury is difficult to be identified due to swelling and pain at the fracture site. It is difficult to observe tibialis posterior tendon injury on a simple radiograph; it is usually found during surgery by accident. There are some studies regarding irreducible ankle fracture-dislocations due to interposition of the tibialis posterior tendon; however, to the best of our knowledge, there has not been any report about interposition of injured tibialis posterior tendon. Herein, we report a case of an irreducible fracture-dislocation of the ankle due to injured tibialis posterior tendon interposition that was observed intraoperatively, interrupting the reduction of ankle fracture-dislocation. We obtained satisfactory clinical result after reduction of the trapped tendon, fracture reduction, and internal fixation; therefore, we are willing to report this case with the consent of the patient. This study was conducted with an approval from the local Institutional Ethics Review Board.

• Journal of the Korean Orthopaedic Association
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• v.56 no.1
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• pp.76-81
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• 2021

A traumatic dislocation of the sternoclavicular joint is a rare injury, and among them, anterior dislocation is more common than a posterior dislocation. Posterior dislocation is a potential risk by compressing the mediastinal structures, but an anterior dislocation has not been considered a risk. Traumatic sternoclavicular joint anterior dislocation associated with anterior angulation of a sternal fracture can develop mediastinal compression and have a risk in the same way as a posterior dislocation. This case report is about a traumatic sternoclavicular joint anterior dislocation with a sternal fracture accompanied by mediastinal compression that was treated surgically using a plate and showed relatively good clinical results. This rare case is reported along with a review of the relevant literature.

• Journal of Korean Foot and Ankle Society
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• v.18 no.3
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• pp.124-128
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• 2014

Purpose: The purpose of this study was to assess the treatment outcomes and prognosis of Lisfranc joint fracture and dislocation according to the mechanism of injury and treatment method. Materials and Methods: Twenty six patients with Lisfranc fracture-dislocation who had been treated surgically were included in this retrospective study. The patients were divided into two groups according to mechanism of injury: direct crushing injury (16 patients) and indirect rotational or compressive injury (10 patients). The patients were also divided into three groups according to the surgical methods. The parameters used were radiographic evaluation, patients' subjective satisfaction levels, length of hospital stay, and the American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score. Statistical analysis was performed. Results: The mean postoperative AOFAS midfoot score was 78.7. The mean length of stay was 39.6 days. Statistically significant differences in subjective satisfaction, AOFAS midfoot score, and length of hospital stay were observed between the two groups (p<0.05). However, no significance differences were observed between the three groups who were divided according to the different surgical methods (p>0.05). Conclusion: Mechanism of trauma and the severity of soft-tissue injury were significant prognostic factors affecting the surgical outcomes of Lisfranc joint fracture and dislocation.

• Journal of Korean Foot and Ankle Society
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• v.4 no.1
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• pp.19-22
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• 2000

Fracture and dislocation of the four lateral metatarsal head and neck at the metatarsophalangeal joint, which may be associated with a hyperextension force, axial load, and additional rotating force, has rarely been reported. The patient was a 32-year-old man who sustained the injury in a motor vehicle accident. Manual reduction was easily performed but maintenance of reduction was difficult, due to the associated fractures of the metatarsal necks. Thus percutaneous internal fixation with Kirshner's wires was required.

• Clinics in Shoulder and Elbow
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• v.5 no.1
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• pp.23-28
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• 2002

Purpose Displaced lateral end fracture of clavicle and acromioclavicular dislocation type Ⅲ∼Ⅵ may be required surgical treatment. Material and Methods : From May 1998 to March 2001, we operated with Welter plate with minimal incision by one surgeon. Immediately, pendulum and passive exercise was initiated after surgery. The shoulder function was evaluated using UCLA score. Average follow up was on 28(12∼45) months. Results : All 11 patients were regained satisfactory function. Average UCLA score was 31.9(29~35) at last follow up. Conclusion . The merit of Welter plate fixation with minimal incision is simple technique, reduced surgical time, smaller scar than large plate, strong fixation, early exercise, reduced implant failure. The disadvantage is expensive, skin irritatatation by long hook. But Welter plate fixation with minimal incision is a good method of internal fixation and excellent clinical result in surgical treatment of type H displaced lateral end fracture of the clavicle and type Ⅲ∼Ⅵ acromioclavicular dislocation.

• Journal of Korean Foot and Ankle Society
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• v.13 no.1
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• pp.106-108
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• 2009

Calcaneus fracture with a subtalar dislocation are extremely rare. A case of a joint depression type calcaneus fracture with a lateral dislocation of the calcaneal posterior facet and tuberosity is presented. We treated it with open reduction and internal fixation with Steinmann pins and K-wires through limited posterior approach and obtained satisfactory radiographic and clinical outcome.

• Journal of Korean Foot and Ankle Society
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• v.8 no.2
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• pp.182-190
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• 2004

Purpose: To evaluate the clinical feature and the results of the treatment of Lisfranc joint fracture/dislocation with limited open reduction, pin fixation and Ilizarov external fixation. Materials and Methods: From June 2001 to May 2003, six patients with Lisfranc fracture/dislocation were treated. The average periods of follow-up was 23 months. After limited open reduction on the second tarso-metatarsal joint, we performed pin fixation of the above joint. On the other Lisfranc joint fracture/dislocation, closed reduction and the application of Ilizarov external fixator was done. This rigid system produced the early partial weight bearing and joint motion of the injured foot and ankle joint. The parameters used were radiographic evaluation, patient's clinical assesment and the AOFAS midfoot score. Results: We used the Myerson's criterier to evaluate the radiographic result. All cases could be achieved more than nearly anatomical reduction. Three cases of excellent and 3 cases of good result could be obtained in the evaluation of the patient's clinical assesment. The average AOFAS midfoot score was 87.2 ($76{\sim}95$) points. Conclusion: The treatment using Ilizarov external fixation on Lisfranc joint fracture/dislocation can be another useful method.

• Journal of Korean Foot and Ankle Society
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• v.12 no.2
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• pp.210-215
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• 2008

Peroneal tendon dislocation in association with calcaneal fracture is not common and difficult to diagnose and is often overlooked. It can result in peroneal tendon tear and tenosynovitis which in turn lead to ankle pain and dysfunction. Early detection with through physical examination and CT scan is important to reduce the subsequent tendon dysfunction. We experienced 6 cases of peroneal tendon dislocation associated with calcaneal fracture, and treated 3 of them at the time of fracture operation and treated the other 3 after calcaneal fracture surgery due to sustained pain. We report the results with a review of the literature.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.205-211
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• 1998

The comminuted fracture and dislocation of the proximal humerus occur more frequently in older patient group and operative treatment is difficult due to poor bone quality. Based on Neer's work, hemiarthroplasty has now become widly accepted for the management of the three-part fracture and four-part fracture-dislocation of the proximal humerus in old age group. The purpose of this study is to evaluate function, pain relief, and patient satisfaction after hemiarthroplasty for proximal humerus fractures and dislocations. Authors reviewed and analyzed 14 prosthetic replacement in comminuted proximal humeral fracture and dislocation at the Department of Orthopaedic Surgery, Yonsei University Wonju College of Medicine from March, 1988 to May, 1997. The results were as follows the average age was 58.9years and the ratio of males and females was 5:9. The most common cause of injury was traffic accident(43%). According to the classification of Neer, three part fracture were three(21%), four-part fracture and four-part fracture-dislocation were eleven(79%). The prosthetic replacement was performed within two weeks in eight patient and six were performed after two weeks. The results were analysed according to Neer's criteria and five cases showed satisfactory results. We concluded that hemiarthroplasty for fracture and dislocation of the proximal humerus facilitated the restoration of humerus length and pain relief, thereby allowing earlier motion to prevent the development of painful shoulder: stiffness.