• Nuclear Engineering and Technology
• /
• 제53권7호
• /
• pp.2304-2311
• /
• 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.

• 대한족부족관절학회지
• /
• 제21권2호
• /
• pp.70-74
• /
• 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.

• 대한정형외과학회지
• /
• 제56권1호
• /
• pp.76-81
• /
• 2021

흉쇄관절의 외상성 탈구는 드문 손상으로 전방 탈구가 후방 탈구에 비하여 흔하다. 후방 탈구는 종격동 구조물을 압박하여 잠재적 위험성이 있다고 잘 알려져 있지만 전방 탈구는 그러한 위험성에 대한 고려가 없었다. 전방 탈구라도 흉골 골절의 전방 각형성과 동반된 경우에 후방 탈구와 마찬가지로 종격동 압박이 발생 가능하며 그로인한 위험성이 있다. 본 저자들은 종격동 압박 증상이 있는 흉골 골절과 동반된 외상성 흉쇄관절 전방 탈구에 대하여 금속판을 이용해 수술적 치료를 시행하였고 비교적 양호한 결과를 얻었다. 이는 국내외에서 매우 드물게 보고되는 사례로 이를 문헌고찰과 함께 보고하고자 한다.

• 대한족부족관절학회지
• /
• 제18권3호
• /
• pp.124-128
• /
• 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.

• 대한족부족관절학회지
• /
• 제4권1호
• /
• pp.19-22
• /
• 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
• /
• 제5권1호
• /
• pp.23-28
• /
• 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.

• 대한족부족관절학회지
• /
• 제13권1호
• /
• pp.106-108
• /
• 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.

• 대한족부족관절학회지
• /
• 제8권2호
• /
• pp.182-190
• /
• 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.

• 대한족부족관절학회지
• /
• 제12권2호
• /
• pp.210-215
• /
• 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
• /
• 제1권2호
• /
• pp.205-211
• /
• 1998

저자들은 상완골 근위부의 골절탈구로 일차성 견관절 반치환술로 치료받은 환자 25례중 14례를 대상으로 치료결과를 분석하여 다음과 같은 결론을 얻었다. 1. 전례에서 동통은 소실되거나 완화되었으나 Neer의 평가에 따라 총 14례중 5례에서만 만족할만 한 결과를 믿었으며 나머지 9례에서는 불만족한 결과를 보였다. 2. 수상시 상완곤두의 분쇄상이 심하거나, 수술이 지연되어 골편치 연화가 심한 경우 상완골 길이와 humeral offset의 유지가 힘들었으며, 견관절 반치환술 시팽한 측이 정상측보다 1cm 이상 단축을 보인 경우가 5례였으며 이 경우 능동적 견관절 운동범위가 정상측보다 감소되었다. 3. 견관절 반치환술은 분쇄상 상완골 근위부 골절에서 사용되어지며 동통의 감소와 기능의 호전은 있으나 완전한 회복은 어려우며 수술시 연부조직 손상이 적고 적당한 후염각, 결절의 재건 과 회전근개의 수복은 필수적이다. humeral offset과 길이의 유지는 술 후 능동적 견관절 운동 범위의 향상에 영향을 미치며 아울러 환자의 협조하에 체계적인 재활운동이 필요할 것으로 사료된다.