• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.17 no.2
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• pp.50-56
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• 2013

• Advances in biomechanics and applications
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• v.1 no.3
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• pp.169-185
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• 2014

Computational multibody models of the elbow can provide a versatile tool to study joint mechanics, cartilage loading, ligament function and the effects of joint trauma and orthopaedic repair. An efficiently developed computational model can assist surgeons and other investigators in the design and evaluation of treatments for elbow injuries, and contribute to improvements in patient care. The purpose of this study was to develop an anatomically correct elbow joint model and validate the model against experimental data. The elbow model was constrained by multiple bundles of non-linear ligaments, three-dimensional deformable contacts between articulating geometries, and applied external loads. The developed anatomical computational models of the joint can then be incorporated into neuro-musculoskeletal models within a multibody framework. In the approach presented here, volume images of two cadaver elbows were generated by computed tomography (CT) and one elbow by magnetic resonance imaging (MRI) to construct the three-dimensional bone geometries for the model. The ligaments and triceps tendon were represented with non-linear spring-damper elements as a function of stiffness, ligament length and ligament zero-load length. Articular cartilage was represented as uniform thickness solids that allowed prediction of compliant contact forces. As a final step, the subject specific model was validated by comparing predicted kinematics and triceps tendon forces to experimentally obtained data of the identically loaded cadaver elbow. The maximum root mean square (RMS) error between the predicted and measured kinematics during the complete testing cycle was 4.9 mm medial-lateral translational of the radius relative to the humerus (for Specimen 2 in this study) and 5.30 internal-external rotation of the radius relative to the humerus (for Specimen 3 in this study). The maximum RMS error for triceps tendon force was 7.6 N (for Specimen 3).

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.765-770
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• 2007

Purpose: Peritendinous adhesion is one of the most notorious complication after the flexor tendon injury. In this study, $Alloderm^{(R)}$(LifeCell Corp., Branchburg, N.J.), which is the decellularized human dermal analogue with its intact native basement membrane components, was used for the prevention of peritendinous adhesions following flexor tendon repair. Methods: Thirty New Zealand white male rabbits were divided equally into 3 groups. In all groups, the flexor digitorum profundus of the third finger of the right back foot was cut totally and repaired by modified Kessler suture technique. Following tendon repair, $Alloderm^{(R)}$ was wrapt around the repaired tendon in the first group and sodium hyaluronate gel was sprayed to the operation field in the second group. In the control group, no external material was applied. The right back foot were immobilized for 6 weeks to optimize the formation of adhesion ingrowth. After death, the third finger that repaired tendons and sheaths was removed en bloc. We checked range of motion. and studied histologically for all groups. Results: The experimental groups had better range of motion than the control group. We checked that the range of motion was 73.5 degrees in $Alloderm^{(R)}$ group, 55.9 degrees in the hyaluronic acid group, and 38.3 degrees in the control group. in the histological study, the experimental group had less adhesions compared with the control group. Conclusion: This study concludes that $Alloderm^{(R)}$ can decrease peritendinous adhesions following flexor tendon repairs in rabbits. We think the method could be used in clinical cases.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.236-239
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• 2009

Purpose: We wanted to evalulate the clinical results of pectoris major tendon transfer for a neglected winged scapula that was caused by paralysis of the serratus anterior due to injury to the long thoracic nerve. Materials and Methods: A patient had neglected winged scapula that followed an arthroscopic operation for multi-directional instability of the shoulder joint, which was caused by traumatic dislocation. The patient was treated with pectoralis major tendon transfer using the modified Eden-Lange procedure. The range of a motion was improved from forward flexion $90^{\circ}$ and external rotation $70^{\circ}$ to $170^{\circ}$ and $150^{\circ}$ respectively. Results and Conclusion: There were no complications or recurrence and the patient's psychological satisfaction was also high. If the shoulder girdle muscles are intact, except for the serratus anterior, then pectoralis tendon transfer is a satisfactory method that can provide normal scapulo-thoracic motion.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.5 s.57
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• pp.121-132
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• 2009

This paper introduces an experimental verification and a field application of the proposed technique using the combination of FEM and HGA about the loss prestressing force of an exteranl tendon by above same authors. The vibration tests have been conducted by using a laboratory models and the externally prestressed tendon at the field and the natural frequencies are extracted from the vibration tests. The proposed technique based on the extracted natural frequencies is applied. It is seen that the errors in the tension and lost prestressing force by proposed technique are about 4% from a laboratory model test. For the model verification at field, exact modeling has beem made with Rayleigh damping. It is seen that the error in the tension by proposed technique is less than 1% and the estimated lost prestressing force converges less than the exact value.

• Structural Engineering and Mechanics
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• v.18 no.4
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• pp.475-491
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• 2004

Anchorage devices play an important role in post-tensioned bridge structures since they must sustain heavy loads in order to permit the transfer of the prestressing force to the structure. In external prestressing, the situation is even more critical since the anchorage mechanisms, with the deviators, are the only links between the structure and the tendons throughout the service life of the structure. The behaviour of anchorage devise may be studied by using the finite element method. To do so, each component of the anchorage must be adequately represented in order to approximate the anchor mechanism as accurately as possible. In particular, the modelling of the jaw/tendon device may be carried out using the real geometry of these two components with an appropriate constitutive contact law or by replacing these components by a single equivalent. This paper presents the numerical study of a mono-strand anchorage device. The results of a comparison between two different representations of the jaw/tendon device, either as two distinct components or as a single equivalent, will be examined. In the double-component setup, the influence of the wedge configuration composing the jaw, and the influence of lubrication of the anchor, will be assessed.

• Clinics in Shoulder and Elbow
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• v.27 no.1
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• pp.126-130
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• 2024

Anterior glenohumeral instability with an irreparable subscapularis tear is a challenging problem for the orthopedic shoulder surgeon. Current techniques, including tendon transfers, yield inconsistent results with high rates of recurrent instability. Acellular dermal allografting has been used in young patients with massive superior rotator cuff tears with early success, but acellular dermal allografting is comparatively unstudied in anterior deficiency. We present two cases of anterior capsular reconstruction with an acellular dermal allograft in patients ages 66 and 58 years with irreparable subscapularis tendon tears. Follow-up for both patients exceeded 4 years, with forward flexion >140°, external rotation exceeding 60°, a Single Assessment Numeric Evaluation score >90 points, a visual analog scale score of 0 points, and an American Shoulder and Elbow Score of 98 points. In conclusion, acellular dermal allografting can be used to reconstruct the anterior capsule in patients with massive irreparable subscapularis tears, similar to its use in superior capsular reconstruction in patients with massive posterosuperior rotator cuff tears.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.475-480
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• 2002

This study is to develop a strengthening method for slab bridges with external prestressing. There are so many different strengthening methods for damaged slab bridges, external prestressing method is the most effective, economical and durable strengthening method among them. But, its problem lies in anchoring devices, so recently, an effective anchoring method was developed and showed its improvements. In this study, a more improved method is suggested. Longitudinal tendons placed on both side of slab strengthens the whole bridge, and lateral tendons placed under the slab strengthens the middle of slab, and conveys the load at middle slab to both sides. Structural analysis for the tensile force for strengthening were analysed. Generally, 200-280tons for longitudinal tendon and 130-190 tons for lateral tendons are good enough to strengthen the damaged slab. This method has no upward roof work, so it is very convenient for installing. And no spaces under the slab are need, so it is good for shallow slabs which has less space under the slab.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.117-120
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• 2006

This study is for the strengthening method of continuous bridge through external tendon strengthening that is the most general and effective among concrete bridge's strengthening method. Recently, it is numerous that slab's parts between spans have continuity for improving trafficable ability. However, in this case, slab would have a crack; bridge's durability would be damaged, and also it is too difficult to manage and maintain bridge due to the tensile strength of negative moment. Therefore, the purpose of this study is to demonstrate load-carrying through experiments and develop new external pre-stressing strengthening method for reinforcing continuous bridge.

• Clinics in Shoulder and Elbow
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• v.26 no.4
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• pp.406-415
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• 2023

Background: Surgical management of a massive rotator cuff tear (RCT) is always challenging. This study describes the clinical and radiological outcomes of patients who underwent bridging grafts using a plantaris tendon for an irreparable RCT. Methods: Thirteen patients with a massive RCT were treated with arthroscopic interposition of a folded plantaris tendon autograft between June 2017 and January 2020. For clinical evaluation, a visual analog scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, Constant-Murley score, and range of motion values were collected. For radiographic evaluation, standardized magnetic resonance imaging and ultrasonography were performed to check the integrity of the interposed tendon. Results: A statistically significant improvement at the final follow-up was evident in scores for the VAS (-3.0, P=0.003), ASES (24.9, P=0.002), D ASH (-20.6, P=0.001), and Constant-Murley values (14.2, P=0.010). In addition, significant improvement was shown in postoperative flexion (17.3°, P=0.026) and external rotation (27.7°, P<0.001). In postoperative radiologic evaluations, the interposed tendons were intact at the last examination in 12 of the 13 patients. No complications related to donor sites were reported. Conclusions: An arthroscopic bridging graft for irreparable RCTs using a modified Mason-Allen stitch and a plantaris autograft resulted in improved short-term radiological and clinical outcomes. Graft integrity was maintained for up to 2 years in most patients. Level of evidence: IV.