• Clinics in Shoulder and Elbow
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• v.20 no.1
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• pp.49-56
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• 2017

Since the olecranon fractures are caused by relatively low-energy injuries, such as a fall from standing height, they are usually found without comminution. Less commonly they can be developed by high-energy injuries and have severe concomitant comminution or injuries to surrounding structures of the elbow. Because the fracture by nature is intra-articular with the exception of some avulsion-type fracture, a majority of olecranon fractures are usually indicated for surgical treatment. Even if there is minimal displacement, surgical treatment is recommended because there is a possibility of further displacement by the traction force of triceps tendon. The most common type of olecranon fracture is displaced, simple non-comminuted fracture (that is, Mayo type IIA fractures). Although tension band wiring was the most widespread treatment method for these fractures previously, there is some trends toward fixation using locking plates. Primary goal of the surgery is to restore a congruent joint and extensor mechanisms by accurate reduction and stable fixation so that range of motion exercises can be performed. The literature has shown that good clinical outcomes are achieved irrespective of surgical fixation technique. However, since the soft tissue envelope around the elbow is poor and the implants are located at the subcutaneous layer, implant irritation is still the most common complication associated with surgical treatment.

• Clinics in Shoulder and Elbow
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• v.24 no.4
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• pp.239-244
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• 2021

Background: Radial neck fracture in children is rare. This study attempted to evaluate the outcome of surgically treated patients and any associated complications. Methods: This study evaluated 23 children under 15 years of age with radial neck fracture who were treated with open reduction between 2006 and 2016 to determine their range of motion, postoperative complications, and radiographic outcomes. The results were assessed clinically using the Mayo clinic elbow performance score. Results: The mean follow-up duration for patients was 34.6 months. The average postoperative angulation was 3.6°. Hypoesthesia was reported in only 9% of patients, and none of the patients complained of postoperative pain. The postoperative X-ray results were excellent in 60% and good in 40%. No radiographic complications were identified. The elbow score was excellent in 87% and good in 13% (mean score, 96.74). There was a statistical relationship between range of motion limitations and age, degree of fracture, initial displacement, and surgical pin removal time. Conclusions: Although most patients accept the closed reduction method as a primary treatment, the present study suggests that an open-reduction approach has been associated with optimal therapeutic outcomes for patients in whom closed reduction was not satisfactory or indicated.

• Structural Engineering and Mechanics
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• v.8 no.4
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• pp.421-438
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• 1999

In this paper a practical limit load estimating procedure is proposed for general pipe-elbow structures subjected to complex loading (in-plane and out-of-plane bending, internal pressure and axial force). The explicit calculating formulae are presented on the basis of theoretical analysis combined with numerical simulation. Von Mises' yield criterion is adopted in both analytical and numerical calculation. The finite element examination shows that the method provides a simple but satisfactory prediction of pipe structures in engineering plastic analysis.

• The Journal of Korea Robotics Society
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• v.8 no.3
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• pp.164-172
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• 2013

This paper presents a new concept of a 1-DOF elbow exoskeleton driven by a twisted strings-based actuator. A novel joint actuation mechanism is proposed and its kinematic model is presented along with its experimental evaluation, and guidelines on how to choose the strings suitable for such an exoskeleton are given. We also proposed and experimentally verified a human intention detection method which takes advantage of intrinsic compliance of the mechanism. The study showed that the developed twisted strings-driven elbow exoskeleton is light, compact and have a high payload-to-weight ratio, which suggests that the device can be effectively used in a variety of haptics, teleoperation, and rehabilitation applications.

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.164-169
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• 2018

A detailed fatigue evaluation procedure was developed to mitigate the excessive conservativeness of the conventional environmental fatigue evaluation method for the pressurizer spray line elbow of domestic new nuclear power plants. The pressurizer spray line is made of austenitic stainless steel, which is relatively sensitive to the environmentally assisted fatigue, and has a low degree of design margin in terms of environmentally assisted fatigue due to the thermal stratification phenomenon on the pipe cross section as a whole or locally. In this study, to meet the environmental fatigue design requirements of the pressurizer spray line elbow, the new environmental fatigue evaluation has been performed, which used the ASME Code NB-3200-based detailed fatigue analysis and the environmental fatigue correction factor instead of the existing NB-3600 evaluation method. As a result, the design requirements for environmentally assisted fatigue were met in all parts of the pressurizer spray line elbow including the fatigue weakened zones by thermal stratification.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.212-220
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• 1998

Concomitant ipsilateral fractures of the humerus, radius and ulna are uncommon combined injury and are also called "floating elbow". It was found that this injury was usually a result of rather severe trauma and frequently associated injuries to other organ systems. It is controversial in the treatment of the "floating elbow", but the current treatment recommendations are open reduction and internal fixation of both the humerus and the forearm fracture with early initiation of range of motion exercises. The authors reviewed thirteen cases of ipsilateral fractures of the humerus, radius and ulna treated in our clinic from January 1992 to March 1997, and average follow-up period was over 18 months(range, 12 to 36 months). The results obtained were as follows; 1. The most common cause of injury was traffic accident and most common location of fractures was mid-third in both humerus and forearm. 2. The shape of fractures was transverse or comminuted in most cases. 3. The good clinical results were obtained by open reduction and internal fixation of both the humerus and the forearm fracture with early initiation of range of motion exercises. 4. The recovery was affected by the severity of the initial trauma and method of the treatment. 5. According to the Lange and Foster method, the functional result was good in 8 cases, fair in 4 cases and poor in 1 cases.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.1
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• pp.73-80
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• 2000

To determine the exact direction and location of the human joint in motion is crucial in developing a more accurate human model and producing a more fitting artificial joint. There have been several reports on the biomechanical analysis of the joint to determine the anatomy and movement of joints. However, all the previous researches were made in vitro study, that is, they investigated the passive movement of the joint from cadavers and the suggested location of the joint axis was difficult to make practical applications due to the lack of the direction of joint axis. Also, in many biomechanical models, each joint axis is assumed to lie horizontally or vertically to the adjacent links. Such an assumption causes inherent inaccuracy. In this study, the direction and location of the transverse elbow axis was obtained with respect to the global coordinate system whose origin is on the lateral epicondyle of the humerus. The suggested result based on the global coordinate system lying on the external landmark will be helpful to understand the information of the axis and to make an application. From the experiments conducted for five subjects, the direction and location of the elbow transverse joint was determined for each subject by the helical axis method. A statistical validation was also performed to confirm the result. Finally, the result was applied to develop a simple elbow model which is a part of the kinematic arm model. The simple elbow movement model was developed to validate the significance of the result and the kinematic arm model was able to describe the geometry of any complex linkage system. As a result, the errors incurred from the proposed model were significantly reduced when compared to the ones from the previous approach.

• Clinics in Shoulder and Elbow
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• v.4 no.1
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• pp.24-29
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• 2001

Purpose: To describe a technique of the modified Neviaser method and to evaluate the clinical outcome of the technique in the treatment of the complete acromioclavicular joint dislocation, Materials and Method: We evaluated 20 patients who were treated by a modified Neviaser method from June 1996 to January 1999, They were followed up for a minimum of two years. The operative technique includes fixation of the acromioclavicular joint, repair of coracoclavicular ligament and transfer of the anterolateral band of coracoacromial ligament. Results: The 20 patients were evaluated clinically using Kang's criteria. The satisfactory results obtained in 85%. The mean coracoclavicular interval ratio was decreased from 2.22 preoperatively to 1.07 postoperatively. At the time of two year follow-up, the mean ratio was 1.20. There was no definite complication such as re-dislocation of the joint. Conclusion: In above type 3 acromioclavicular dislocation, the modified Neviaser method provided the advantage of strong and stable fixation with a low complication rate. Therefore, it is thought to be one of the useful operative technique.

• Clinics in Shoulder and Elbow
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• v.20 no.4
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• pp.244-249
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• 2017

Shoulder kinematics is important, as it is associated with shoulder arthropathy and pain mechanisms. Various static and dynamic analysis methods are prevalent for shoulder kinematics. These include 2-dimensional plane x-ray, computed tomography, and magnetic resonance imaging, cadaver study, electromagnetic motion analysis, transcortical bone pins technique, and in vivo 3-dimensional motion analysis. Although these methods provide the value of the shoulder kinematics angle, they are unable to explain why such changes occur. Since each method has its pros and cons, it is important to understand all factors accurately, and to choose a method that best meets the purpose of the researcher.

• Clinics in Shoulder and Elbow
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• v.19 no.4
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• pp.237-240
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• 2016

Retear patterns after arthroscopic rotator cuff repair are classified into two patterns according to retear location. Type 1 is when the retear pattern occurs directly on the tendon at the bone repair site using the suture anchor repair method. Type 2 is when the retear pattern occurs at the musculocutaneous junction with a healed footprint in patients who undergo the suture bridge method. Here, the authors report another retear pattern, which was identified as a type 2 retear on magnetic resonance imaging in patients who had undergone arthroscopic rotator cuff repair by the suture-bridge technique. This pattern was different from the type 2 retear and occurred at the portion of the cuff away from the healed rotator cuff under the view of the arthroscope.