• Journal of Industrial Technology
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• v.21 no.B
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• pp.195-203
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• 2001

The purpose of this study is to estimate ultimate uplift capacity of permanent anchor which was cast into weathered rock. The ultimate uplift capacity was estimated from the load-displacement curve of four different anchors which have different bond length. The creep test was performed for 15minutes under the maximum load of each step in order to understand the load-transfer property of permanent anchor and to decide which anchor to choose. The destruction range of soil due to the changes in load was estimated by installing dial gauge on the ground which was cast into the weathered rock. Ultimately, the study on the behavior of the anchor case into the weathered rock was performed by comparing and analyzing the estimated result of the UUC obtained by the full scale pull out test in the field with the exsting theoretical and practical results of soil and rock anchor.

• Clinics in Shoulder and Elbow
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• v.17 no.3
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• pp.145-150
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• 2014

In the patients of retracted massive rotator cuff tears, there are much of difficulty to functional recovery and pain relief. Nevertheless the development of treatment, there are still debates of the best treatments in the massive rotator cuff tears. Recenlty various of treatments are introduced; these are acromioplasty with debridement, biceps tenotomy, great tuberoplasty with biceps tenotomy, partial repair, mini-open rotator cuff repair, arthroscopic rotator cuff repair, soft tissue augmentation, tendon transfer, flap, hemiarthroplasty, and reverse total shoulder arthroplasty. That there is no difference of result for reverse total shoulder arthroplasty between patients who have massive rotator cuff tear without arthritis and patients who have cuff tear arthropathy. Reverse total shoulder arthroplasty is one of reliable and successful treatment options for massive rotator cuff tear. Especially it is more effective for patients who have a pseudoparalysis.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.4
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• pp.307-315
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• 2008

Post-tensioned precast concrete system (PPS) consists of U-shaped precast wide beams and concrete column. The continuity of beam-column joint is provided with the topping concrete on the PC shell beam and post-tensioning. Nonlinear analysis was conducted, using ANSYS, a finite-element analysis program, to obtain data for determining the characteristics of the structure and to allow various parametric analyses for post-tensioned wide beam-column connections. In this analysis, the Solid 65 element was used, in which concrete element had 8 nodes and each node had 3 degrees of freedomIn. Solid 65, the shear-transfer factor reflects a decrease of shear strength for the positions with cracks, as an impact factor to make the analysis value approximate the experiment value. In this study, the behavior of test specineus were most closely predicted to the experimental results, when the shear-transfer coefficient 0.85 was used for a closed crack, and 0.2 was used for an open crack.

• Journal of Korean Foot and Ankle Society
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• v.18 no.2
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• pp.62-67
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• 2014

Purpose: Reconstructive surgeries for equinocavovarus foot deformities are quite variable, including hind-midfoot osteotomy or arthrodesis, soft tissue procedure, tendon transfers, etc. Comprehensive evaluation of the deformity and its etiology is mandatory for achievement of successful deformity correction. Few studies in this field have been reported. We report on the clinical and radiographic outcome of reconstruction for cavovarus foot deformities. Materials and Methods: The study is based on 16 feet with cavovarus foot deformities that underwent bony and soft tissue reconstructive surgery from 2004 to 2008. We evaluated the etiologies, varieties of surgical procedures performed, pain score, functional scores, and patient satisfaction and measured the radiographic parameters. Results: The average age at the time of surgery was 39.4 years old, with a male/female ratio of 9/4 and an average follow-up period of 23.9 months (range, 12~49 months). The etiologies of the cavovarus deformity were idiopathic 7 feet, residual poliomyelitis 5 feet, Charcot-Marie-Tooth disease 2 feet, and Guillain-Barre syndrome and hemiplegia due to cerebrovascular accident sequela 1 foot each. Lateral sliding calcaneal osteotomies were performed in 12 feet (75%), followed by Achilles tendon lengthening and plantar fascia release in 11 feet (69%), and first metatarsal dorsiflexion osteotomy/arthrodesis and tendon transfer in 10 feet (63%). Visual analogue scale pain score showed improvement, from an average of 4.2 to 0.5 points. American Orthopaedic Foot and Ankle Society ankle-hindfoot score showed significant improvement, from 47.8 to 90.0 points (p<0.05). All patients were satisfied. Ankle range of motion improved from $27.5^{\circ}$ to $46.7^{\circ}$. In radiographic measurements, calcaneal pitch angle improved from $19.1^{\circ}$ to $15.8^{\circ}$, Meary angle from $13.0^{\circ}$ to $9.3^{\circ}$, Hibb's angle from $44.3^{\circ}$ to $37.0^{\circ}$, and tibio-calcaneal axis angle from varus $17.5^{\circ}$ to varus $1.5^{\circ}$ Conclusion: We achieved successful correction of cavovarus foot deformities by performing appropriate comprehensive reconstructive procedures with improved functional, radiographic measures and high patient satisfaction.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.836-844
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• 2011

Purpose: Hands are the chief organs for physically manipulating the environment, using anywhere from the roughest motor skills to the finest, and since the fingertips contain some of the densest areas of nerve endings on the human body, they are continuously used organ with complex functions, and therefore, often gets injured. To prevent any functional loss, a detailed anatomical knowledge is required to have a perfect surgical treatment. Also it is necessary to have a thorough understanding of arrangements of the human extensor tendons and intertendinous connections when tenoplasty or tendon transfer is required. We performed a study of the arrangements of the human extensor tendons and the configuration of the intertendinous connections over the dorsum of the wrist and hand. Methods: A total of 58 hands from Korean cadavers were dissected. The arrangements of extensor indicis proprius, extensor digitorum communis, and extensor digiti minimi tendons and intertendinous connections were studied. Results: The most common distribution patterns of the extensor tendons of the fingers were as follows: a single extensor indicis proprius (EIP) tendon which inserted ulnar to the extensor digitorum-index (EDC-index); a single EDC-index; a single EDC-middle; a double EDC-ring; an absent EDC-little; a double extensor digiti minimi (EDM), a single EDC-index (98.3%), a single EDC-middle (62%), a double EDC-ring (50%), and an absent (65.5%) or a single (32.8%) EDC-little. A double (70.6%) EDM tendons were seen. Intertendinous connections were classified into 3 types: type 1 with thin filamentous type, type 2 with a thick filamentous type, and type 3 with a tendinous type subdivided to r shaped 3r type and y shaped 3y type. The most common patterns were type 1 in the 2nd intermetacarpal space, type 2 in the 3rd intermetacarpal space, and type 3r in the 4th intermetacarpal space. And in the present study, we observed one case of the extensor digitorum brevis manus (EDBM) on the boht side. Conclusion: A knowledge of both the usual and possible variations of the extensor tendon and the intertendinous connection is useful in the identification and repair of these structures.

• Journal of Biomedical Engineering Research
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• v.34 no.3
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• pp.141-147
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• 2013

Ultrasonic shears is currently in wide use as an energy device for minimal invasive surgery. There is an advantage of minimizing the carbonization behavior of the tissue due to the vibrational energy transfer system of the transducer by applying a piezoelectric ceramic. However, the vibrational energy transfer system has a pitfall in energy consumption. When the movement of the forceps is interrupted by the tissue, the horn which transfers the vibrational energy of the transducer will be affected. A study was performed to recognize different tissues by measuring the impedance of the transducer of the ultrasonic shears in order to find the factor of energy consumption according to the tissue. In the first stage of the study, the voltage and current of the transducer connecting portion were measured, along with the phase changes. Subsequently, in the second stage, the impedance of the transducer was directly measured. In the final stage, using the handpiece, we grasped the tissue and observed the impedance differences appeared in the transducer To verify the proposed tissue distinguishing method, we used the handpiece to apply a force between 5N and 10N to pork while increasing the value of the impedance of the transducer from 400 ${\Omega}$.. It was found that fat and skin tissue, tendon, liver and protein all have different impedance values of 420 ${\Omega}$, 490 ${\Omega}$, 530 ${\Omega}$, and 580 ${\Omega}$, respectively. Thus, the impedance value can be used to distinguish the type of tissues grasped by the forceps. In the future study, this relationship will be used to improve the energy efficiency of ultrasonic shears.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.68-72
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• 1998

With the advent of microvascular free-tissue transfer, this single stage resurfacing method for large scar and soft tissue defects around the wrist in the patients of electrical burn has distinctive advantage over the conventional multistage pedicle-flap transfer. Between 1992 and 1996, we treated 9 cases of 8 patients who had large scar around the wrist due to old electrical burn with free flaps as a preparation of staged tendon graft. Mean age was 30.3 years and average scar area was $6{\times}11cm$. The length of time the injury and free flaps was 9 months on an average. Prior to the free flap, we performed the angiography to all patients in order to evaluate the circulation of the forearm and hand and to choose the recipient vessel. In all cases, proximal ulnar arteries in the forearm remained intact and all radial arteries remained intact in 8 of 9 cases on angiogram. The interosseous arteries were well visualized in all cases. We used the ulnar arteries as a recipient artery. The types of flaps used were f scapular cutaneous flaps, 2 dorsalis pedis flaps and a radial forearm flap. Flap survial was 100 percents with satisfactory functional and cosmetic results. Free flaps using ulnar artery as a recipient artery is one of the useful reconstruction methods for the resurfacing of large scar around the wrist in the patients of old electrical burn.

• Journal of Korean Neurosurgical Society
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• v.46 no.1
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• pp.1-4
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• 2009

Objective: To report an unsuspected adaptive plasticity of single upper motor neurons and of primary motor cortex found after microsurgical connection of the spinal cord with peripheral nerve via grafts in paraplegics and focussed discussion of the reviewed literature. Methods: The research aimed at making paraplegics walk again, after 20 years of experimental surgery in animals. Amongst other things, animal experiments demonstrated the alteration of the motor endplates receptors from cholinergic to glutamatergic induced by connection with upper motor neurons. The same paradigm was successfully performed in paraplegic humans. The nerve grafts were put into the ventral-lateral spinal tract randomly, with out possibility of choosing the axons coming from different areas of the motor cortex. Results: The patient became able to selectively activate the re-innervated muscles she wanted without concurrent activities of other muscles connected with the same cortical areas. Conclusion: Authors believe that unlike in nerve or tendon transfers, where the whole cortical area corresponding to the transfer changes its function a phenomenon that we call "brain plasticity by areas". in our paradigm due to the direct connection of upper motor neurons with different peripheral nerves and muscles via nerve grafts motor learning occurs based on adaptive neuronal plasticity so that simultaneous contractions of other muscles are prevented. We propose to call it adaptive functional "plasticity by single neurons". We speculate that this phenomenon is due to the simultaneous activation of neurons spread in different cortical areas for a given specific movement, whilst the other neurons of the same areas connected with peripheral nerves of different muscles are not activated at the same time. Why different neurons of the same area fire at different times according to different voluntary demands remains to be discovered. We are committed to solve this enigma hereafter.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.451-459
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• 2020

Background For volar soft tissue defects of the proximal interphalangeal (PIP) joint, free flaps are technically challenging, but have more esthetic and functional advantages than local or distant flaps. In this study, we compared the long-term surgical outcomes of arterial (hypothenar, thenar, or second toe plantar) and venous free flaps for volar defects of the PIP joint. Methods This was a single-center retrospective review of free flap coverage of volar defects between the distal interphalangeal and metacarpophalangeal joint from July 2010 to August 2019. Patients with severe crush injuries (degloving, tendon or bone defects, or comminuted/intra-articular fractures), thumb injuries, multiple-joint and finger injuries, dorsal soft tissue defects, and defects >6 cm in length were excluded from the study, as were those lost to follow-up within 6 months. Thirteen patients received arterial (hypothenar, thenar, or second toe plantar) free flaps and 12 received venous free flaps. Patients' age, follow-up period, PIP joint active range of motion (ROM), extension lag, grip-strength ratio of the injured to the uninjured hand, and Quick Disabilities of Arm, Shoulder & Hand (QuickDASH) score were compared between the groups. Results Arterial free flaps showed significantly higher PIP joint active ROM (P=0.043) and lower extension lag (P =0.035) than venous free flaps. The differences in flexion, grip strength, and QuickDASH scores were not statistically significant. Conclusions The surgical outcomes of arterial free flaps were superior to those of venous free flaps for volar defects of the PIP joint.

• Archives of Reconstructive Microsurgery
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• v.6 no.1
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• pp.87-95
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• 1997

Traumatic injury to the hand often leads to soft tissue defects with exposed tendons, bones, or joints. Though many new flap have been introduced, the choice of flap that would be best for the patient depends on such factors as the site, size, and degree of wounds. Additionally the selected surgical method should be yielded cosmetic and functional superiority by the one-staged reconstruction. In our experience, small to medium sized soft tissue defect with bone and tendon exposure of hand can be resurfaced with an arterialized venous free flap from the volar aspect of distal forearm. Wide and deep defects of the hand can be covered with a sensory cutaneous free flap such as the medial plantar free flap, dorsalis pedis free flap, and radial forearm free flap. Specialized flap such as wrap-around flap, toe-to-finger transfer, onychocutaneous free flap can be used for the recontruction of defect on the thumb and finger. Based on the above considerations and our clinical experience of 60 free flap cases of the hand, the various methods for the proper repair of soft tissue defects of the hand are described. And we obtained satisfactory functional and cosmetic results with 95% success rate of free flap.