• Clinics in Shoulder and Elbow
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• v.2 no.2
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• pp.126-132
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• 1999

Purpose : To evaluate the functional and radiographic outcome of the modified Bosworth method in the surgical treatment of acute type V acromioclavicular joint dislocation. Materials and Methods: From June 1995 to May 1998, 20 patients were operated on for acute and complete acromioclavicular dislocation(Rockwood type V). The operative technique includes fixation of the coracoclavicular joint with Bosworth screw or 6.5mm cancellous screw and imbrication of trapezius and deltoid muscles. The average age was 34 years(range, 19 to 51 years). These 20 patients with an average follow-up of 18months, were evaluated clinically using the UCLA scoring system. Additional radiographical assessment was performed with stress radiographs. Results: Excellent or good clinical results were obtained in 95%(19 cases). And the average coracoclavicular interval ratio was decreased from 3.31(2.2-6.0) to 1.13(1-1.4) in stress radiographs. There were 4 cases of hetero­topic calcification postoperatively but there was no correlation with clinical result. Posttraumatic A-C joint arthritis was developed in one case. In that case, the distal clavicular resection was done under the arthroscopic technique. Conclusion: The severe displacement observed with type V injuries is incompatible with normal shoulder function if the shoulder is left in its displaced position. In type V injuries, significant damage to the deltoid and trapezius musculature and overlying fascia occurs, therefore open reduction and good fixation must be obtained with imbrication of trapezius and deltoid muscles. In our type V acute complete acromioclavicular dislocation, the modified Bosworth technique provides excellent results with a low complication rate.

• Clinics in Shoulder and Elbow
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• v.21 no.1
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• pp.48-55
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• 2018

While non-operative treatment with structured rehabilitation tends to be the strategy of choice in the management of Rockwood type III acromioclavicular joint injury, some advocate surgical treatment to prevent persistent pain, disability, and prominence of the distal clavicle. There is no clear consensus regarding when the surgical treatment should be indicated, and successful clinical outcomes have been reported for non-operative treatment in more than 80% of type III acromioclavicular joint injuries. Furthermore, there is no gold standard procedure for operative treatment of type III acromioclavicular joint injury, and more than 60 different procedures have been used for this purpose in clinical practice. Among these surgical techniques, recently introduced arthroscopic-assisted procedures involving a coracoclavicular suspension device are minimally invasive and have been shown to achieve successful coracoclavicular reconstruction in 80% of patients with failed conservative treatment. Taken together, currently available data indicate that successful treatment can be expected with initial conservative treatment in more than 96% of type III acromioclavicular injuries, whereas minimally invasive surgical treatments can be considered for unstable type IIIB injuries, especially in young and active patients. Further studies are needed to clarify the optimal treatment approach in patients with higher functional needs, especially in high-level athletes.

• Clinics in Shoulder and Elbow
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• v.11 no.1
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• pp.46-52
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• 2008

Purpose: This study examined the outcomes of reconstruction of the coracoclavicular ligaments with using two suture anchors and performing coracoacromial ligament transfer in patients with acromioclavicular dislocation. Material and methods: Forty patients with complete acromioclavicular dislocation were included in this study. According to the preoperative radiographs, 5 patients with AC dislocations were diagnosed as type III, 4 patients as type IV and 31 patients as type V. Two 3.5mm suture anchors with four strands of nonabsorbable sutures were separately placed on the anterolateral and posteromedial portion of the base of the coracoid process to stabilize the distal clavicle. The coracoacromial ligament was then transferred to the undersurface of the distal end of the clavicle for augmentation. Results: At a mean follow-up of 28 months, the average Constant score improved to 97 points. All the patients returned to normal life at an average of 3.2 months postoperatively. At the last follow-up, 37 patients achieved anatomical reduction and three patients showed complete redislocation. However, the clinical results of the patients with redislocation were satisfactory. Conclusion: Anatomical coracoclavicular reconstruction using two suture anchors and coracoacromial ligament transfer for treating complete acromioclavicular dislocation is a safe, effective procedure for restoring a physiologically stable acromioclavicular joint.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.266-269
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• 2010

Purpose: We report case of neglected elbow dislocation for three years. Material and method: A 45 years old female patient presented with neglected elbow dislocation for three years. Since the patient had contracture in both lateral and medial collateral ligament of elbow, dissection was done. After total separation of posterior articular capsule and incision of anterior articular capsule, by manual manipulation, reduction of radiohumeral and ulnohumeral joints were obtained. We applied modified Morrey type hinged external fixation in the elbow and done early elbow exercise. Result and Conclusion: Since we have experienced a satisfactory result in the case with neglected elbow dislocation for 3 years by using open reduction and hinged external fixation, we report it with the literature.

• Clinics in Shoulder and Elbow
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• v.6 no.1
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• pp.80-84
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• 2003

We report a patient with an anterior dislocation of the shoulder with uncommon bucket handle type fracture of the anterior glenoid fossa with intact glenoid labrum. The fracture fragment was displaced into the posterior aspect of the glenohumeral joint resulting in prevention of reduction of the shoulder. Excellent fixation was obtained with suture anchors and bioabsorbable interfragmentary screws. This allowed stable range of motion exercises, optimizing the patient's functional outcome.

• Ceramist
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• v.9 no.6
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• pp.49-55
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• 2006

Intra-type alumina-based nanocomposites, in which second-phase nanoparticles are embedded within alumina grains, use dislocation activities to enhance strength and fracture toughness. The dislocations are generated around the nanoparticles by residual stresses during cooling process. In this paper, first, we explain strengthening and toughening mechanisms of alumina-based nanocomposites based on dislocation activities. Second, we propose a soaking method to construct the intra-type nanostructure and fabricate alumina/nickel and alumina/silver nanocomposites. The nanocomposites are then annealed in order to enhance the fracture toughness of the materials. Finally, we discuss the relation between the strength, fracture toughness, and critical frontal process zone size of the materials.

• Journal of Mechanical Science and Technology
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• v.20 no.8
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• pp.1209-1216
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• 2006

An AZ31 magnesium alloy was tested at constant temperatures ranging from 423 to 473 K (0.46 to 0.51 Tm) under constant stresses. All of the creep curves exhibited two types depending on stress levels. At low stress (${\sigma}/ G < 4 {\times}10^{-3}$), the creep curve was typical of class A (Alloy type) behavior. However, at high stresses (${\sigma}/ G > 4 {\times}10^{-3}$), the creep curve was typical of class M (Metal type) behavior. At low stress level, the stress exponent for the steady-state creep rate was of 3.5 and the true activation energy for creep was 101 kJ/mole which is close to that for solute diffusion. It indicates that the dominant deformation mechanism was glide-controlled dislocation creep. At low stress level where n=3.5, the present results are in good agreement with the prediction of Fridel model.

• Structural Engineering and Mechanics
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• v.86 no.4
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• pp.535-546
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• 2023

In the present paper, multiple interface cracks between a functionally graded orthotropic coating and an orthotropic half-plane substrate under concentrated loading are considered by means of the distribution dislocation technique (DDT). With the use of integration of Fourier transform the problem is reduced to a system of Cauchy-type singular integral equations which are solved numerically to compute the dislocation density on the surfaces of the cracks. The distribution dislocation is a powerful method to calculate accurate solutions to plane crack problems, especially this method is very good to find SIFs for multiple unequal cracks located at the interface. Hence this technique allows considering any number of interface cracks. The primary objective of this paper is to investigate the effects of the interaction of multiple interface cracks, load location, material orthotropy, nonhomogeneity parameters and geometry parameters on the modes I and II SIFs. Numerical results show that modes I/II SIFs decrease with increasing the nonhomogeneity parameter and the highest magnitude of SIF occurs where distances between the load location and crack tips are minimal.

• Clinics in Shoulder and Elbow
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• v.18 no.3
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• pp.144-151
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• 2015

Background: The consensus is that a bony Bankart lesion shorter than 25% of the length of glenoid does not affect the clinical result; hence, such lesions were often neglected. However, small bony Bankart lesions are associated with various types of capsulolabral lesions. Methods: A total of 82 patients who had undergone arthroscopic capsulolabral lesion repair surgery for anterior shoulder dislocation were reviewed. The prevalence rates of early and late type of capsulolabral lesions were compared between a group of patients with and a group without small bony Bankart lesions. In addition, the types of accompanying capsulolabral lesion were analyzed according to the type of bony Bankart lesion. Finally, the clinical outcomes were evaluated (active range of motion, American Shoulder and Elbow Surgeons score and Rowe's score). Results: Among the 13 patients who had small bony Bankart lesions, the prevalence rate of early and late type of capsulolabral lesions was 38.5% and 61.5%, respectively. Among the 69 patients without bony Bankart lesion, the prevalence rates of early and late type of capsulolabral lesions were 74% and 26%, respectively. Significantly worse clinical outcome was observed for the group of patients with both small bony Bankart lesions and late type of capsulolabral lesion. Conclusions: More severe type of small bony Bankart lesion appears to be associated with late type of capsulolabral lesion. The significantly worse clinical outcome for patients with both small bony Bankart lesion and late type of capsulolabral lesion indicates that small bony Bankart lesions cannot always be neglected.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.175-179
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• 1998

The acromioclavicular joint is commonly affected by traumatic and degenerative conditions. Most injuries are due to direct trauma, such as a fall on the shoulder. Although there is general agreement on treatment of type I, Ⅱ, Ⅳ, V and VI acromioclavicular injuries, the treatment of type Ⅲ injuries remains controversial. Sixty patients, ranging in age from 19 to 57 years(average, 32), were evaluated an average of 57.5 (range, 13 to 96) months after surgical reconstruction for Rockwood type Ⅲ Ⅳ, V acromioclavicular dislocation. Phemister method (47 cases), Bosworth (3 cases), Weaver and Dunn method (10 cases) were used to correct displacement. An increase of the coracoclavicular distance of the injured shoulder over the normal shoulder was average 7.1㎜ at initial, average l㎜ on postoperatively, and average 2㎜ at follow-up. Overall, 54 of 60(90%) patients achieved satisfactory results. Degree of increase of the coracoclavicular distance has no inliluence to clinical results.