• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.240-244
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• 2009

Purpose: This study examined the outcomes of closed reduction and fixation of the coracoid process fracture using a suture anchor in a patient with combined acromioclavicular dislocation for which the coraco-clavicular ligament was intact. Materials and Methods: A 26 year-old male patient with a coracoid process fracture that was associated with a type III acromioclavicular joint dislocation was operated on with anchor suture fixation. This is the first trial of this operative procedure. Results: At the postoperative follow-up at 3 months, complete union of the coracoid process fracture was seen. The shoulder had a full range of motion and the shoulder function was normal. Conclusion: Closed reduction and fixation using one suture anchor for treating coracoid process fracture is a safe, effective procedure.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.1
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• pp.188-195
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• 2002

To investigate the degradation of mechanical properties induced mainly by neutron irradiation, the tensile tests were conducted from room temperature to 300\\`c using the irradiated and the unirradiated Zr-2.5Nb pressure tube materials. The irradiated longitudinal and transverse specimens were collected from the coolant inlet, middle, and outlet parts of M-11 tube which had been operated in Wolsung CANDU Unit-1 and exposed to different operating temperatures and irradiation fluences. The different tensile behavior was characterized not by the fluences of irradiation but by the tensile loading direction. The transverse specimen showed the higher strength and lower elongation than those of the longitudinal one. It was believed that these phenomena resulted from the microstructure anisotropy caused by the extrusion process. The increased strength hardening and decreased elongation embrittlement of the irradiated material were compard to those of the unirradiated one. While the tensile strength of the inlet was higher than that of the outlet, the elongation of the inlet was lower than that of outlet. Considering the operation condition, it was proposed that the operating temperature could be a more effective parameter than the irradiation fluence for long-time life. Through the TEM observation, it was found that while the a-type dislocation density was increased, the c-type dislocation was not changed in the irradiated. The fact that the higher dislocation density was sequentially distributed over the inlet, the middle, and the outlet parts was consistent with the distribution of the tensile strength.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.26-34
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• 1998

The management of acute acromioclavicular dislocations has usually followed the accepted principles of obtaining an anatomical reduction of the joint and maintaining it until soft tissue healing has occurred. So, the preferred treatment for acute acromioclavicular dislocation is controversial. We analysed operatively treated twenty-eight cases for acute acromioclavicular dislocation between February 1994 and January 1997 and reviewed postoperatively to evaluate the results of three different methods. We collected retrospectively the data via clinical history, associated injury, type of injury, radiographic review, Taft score, and final results. Follow up time averaged 14 months. (range, 12 to 21 ) In according to Rockwood's classification, ]7 cases were type Ⅲ, 1 case was type IV, and 10 cases were type V. Ten cases were treated with the modified Phemister method, ten cases with the modified Bosworth method and eight cases with the modified Weaver-Dunn method. ]n patients treated by modified Phemister method, the Taft score was 9.4 points and 8 cases achieved good or excellent results. In patients treated by modified Bosworth method, the Taft score was 9.8 points and 8 cases achieved good or excellent results. In patients treated by modified Weaver-Dunn method, the Taft score was 10.3 points and 7 cases achieved good or excellent results. The overall Taft score was 9.9 points and 23 cases achieved good or excellent results. There were four complications, such as calcification or metallic loosening or breakage of K-wire, but did not influence late results. In conclusions, there was no significant difference of results regarding the different three methods. However, our results indicated that the coracoclavicular ligament reconstruction by transfer of coracoacromial ligament produced better results.

• Structural Engineering and Mechanics
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• v.64 no.1
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• pp.71-79
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• 2017

In this study, interaction of several interface cracks located between a functionally graded material (FGM) layer and an elastic layer under anti-plane deformation based on the distributed dislocation technique (DDT) is analyzed. The variation of the shear modulus of the functionally graded coating is modeled by an exponential and linear function along the thickness of the layer. The complex Fourier transform is applied to governing equation to derive a system of singular integral equations with Cauchy type kernel. These equations are solved by a numerical method to obtain the stress intensity factors (SIFs) at the crack tips. The effects of non-homogeneity parameters for exponentially and linearly form of shear modulus, the thickness of the layers and the length of crack on the SIFs for several interface cracks are investigated. The results reveal that the magnitude of SIFs decrease with increasing of FG parameter and thickness of FGM layer. The values of SIFs for FGM layer with exponential form is less than the linear form.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.98-101
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• 2009

Purpose: These case reports have been prepared to highlight the uncommon occurrence of anterior shoulder dislocation after an epileptic seizure, the recognition of which is important as this type of injury is associated with bony lesions and a high incidence of recurrence. Materials and Methods: We report two cases of recurrent anterior dislocation of the shoulder due to grand mal epilepsy. These cases were treated as usual anterior dislocations of the shoulder, and were regularly followed to detect any recurrence of shoulder instability. Results: Outcome of the surgery in the two cases was different because of the differences in seizure control. In the patient in whom seizures were well-controlled, there was no recurrence of instability, while the patient with poorly controlled seizures developed a recurrence of the dislocation following shoulder repair. Conclusion: The authors emphasize the need to control seizures in order to prevent injury recurrence in this subset of patients.

• Journal of the Korean Arthroscopy Society
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• v.15 no.1
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• pp.13-18
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• 2011

Purpose: The purpose of this study is to evaluate the radiologic and clinical results of the arthroscopic coracoclavicular fixation of the acute acromioclavicular dislocation using $TightRope^{(R)}$ (Arthrex, Inc, Naples, FL). Materials and Methods: We performed the arthroscopic coracoclavicular fixation using $TightRope^{(R)}$ in twenty patients with the Rockwood type III or V acute acromioclavicular dislocation between February, 2009, and February, 2010. Mean follow-up was 13.4(range 8~22) months. Radiologic results were evaluated by comparing the distances between the clavicle and the coracoid process with those in the contralateral sides using the acromioclavicular stress radiographs. Clinical results were made according to the KSS(Korean Shoulder Scoring System), and the cosmetic satisfaction of the patient was assessed. Results: Radiologically, 18 cases showed excellent, 1 case showed good and 1 case showed fair results. Clinically, KSS was mean 98.5 (range 92~100) points and all cases revealed satisfactory cosmetic results. Because one case complained of skin tenderness and discomfort of palpation, we closed the knot with surrounding muscle & fascia. Then local wound infection occurred, so we treated it by incision and drainage under local anesthesia and antibiotic therapy for 2 weeks. Conclusion: Arthroscopic coracoclavicular fixation using $TightRope^{(R)}$ for treating the Rockwood type III or V acute acromioclavicular dislocation showed satisfactory radiologic and clinical results. It seems to be a good treatment method that has little postoperative complication, provides an early rehabilitation and an excellent cosmetic result, and does not require secondary operation for removal of metal implant.

• Clinics in Shoulder and Elbow
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• v.7 no.1
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• pp.1-4
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• 2004

As the multidirection and posterior instabilities of the shoulder are not only uncommon but responds well to conservative treatment, the shoulder instabilities which requires surgical treatment are traumatic anterior type in most cases, Although various surgical procedures had been used in the past, Bankart procedure is the standard surgical method as a primary procedure in traumatic anterior instability, Nevertheless there has been changes in the techniques of Bankart procedure in order to minimize decrease of external rotation and effectively address capsular laxilty, Capsular shift might be needed if there remains excessive capsular laxity of the inferior capsule after repair of the Bankart lesion, Large bony Bankart lesion should be fixed if possible and severe glenoid rim erosion requires extracapsular bone block after repair of the capsule. Although a few surgical procedures are described for the management of Hill-Sachs lesion in special circumstances, Hill-Sachs lesion does not usually need to be addressed.

• Interaction and multiscale mechanics
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• v.1 no.4
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• pp.423-435
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• 2008

This paper employs the reproducing kernel (RK) approximation for evaluation of field theory-based incompatibility tensor in a polycrystalline plasticity simulation. The modulation patterns, which is interpreted as mimicking geometrical-type dislocation substructures, are obtained based on the proposed method. Comparisons are made using FEM and RK based approximation methods among different support sizes and other evaluation conditions of the strain gradients. It is demonstrated that the evolution of the modulation patterns needs to be accurately calculated at each time step to yield a correct physical interpretation. The effect of the higher order strain derivative processing zone on the predicted modulation patterns is also discussed.

• Clinics in Shoulder and Elbow
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• v.22 no.3
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• pp.149-153
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• 2019

We experienced acromial erosion and subsequent fracture after the treatment of Rockwood type V acromioclavicular dislocation with hook plate and coracoclavicular ligament augmentation. It was treated by using a surgical technique to address an acromial fracture and subsequent losses of reduction in acromioclavicular joint with two trans-acromial cortical screws (crossbar technique). The reduction state of acromioclavicular joint could be maintained by these two screws. Our crossbar technique could be considered as a good salvage procedure for the reduction loss caused by cutout or significant erosion of acromion after insertion of clavicular hook plate.

• Korean Journal of Materials Research
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• v.18 no.8
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• pp.450-453
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• 2008

Mg-doped and In-Mg co-doped p-type GaN epilayers were grown in a low-pressure metal organic chemical vapor deposition technique. The effect of In doping on the p-GaN layer was studied through photoluminescence (PL), persistent photoconductivity (PPC), and transmission electron microscopy (TEM) at room temperature. For the In-doped p-GaN layer, the PL intensity increases significantly and the peak position shifts to 3.2 eV from 2.95 eV of conventional p-GaN. Additionally, In doping greatly reduces the PPC, which was very strong in conventional p-GaN. A reduction in the dislocation density is also evidenced upon In doping in p-GaN according to TEM images. The improved optical properties of the In-doped p-GaN layer are attributed to the high crystalline quality and to the active participation of incorporated Mg atoms.