• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.65-71
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• 1996

In the design of wood structures, the consideration of the dynamic load effect has been increased. Generally, damping ratio is presented as the method of considering dynamic load effect. So, the relationship between joint type and damping ratio was investigated. It has been known that the joint extremely damp the dynamic load in wood structures. Static test was performed to determine the effects of nail size and friction area on joint strength and stiffness. Joint strength and stiffness were increased with nail size. However, the static properties of joint was not affected by friction area. Cyclic test was performed to determine the effects of nail size, friction area and load magnitude on damping ratio, Damping ratio was affected by all factors. Increasing the width of the bottom plate was suggested as the most adequate method to increase the damping ratio without the reduction of the static properties of the structures.

• Structural Engineering and Mechanics
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• v.28 no.2
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• pp.239-257
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• 2008

Double-sided punched metal plate timber fasteners present projections on both sides, which offer improved joint fire resistance and better joint aesthetics. In this paper, 3-D nonlinear finite element models were developed to simulate double-sided nail plate fastener timber joints. The models, incorporating orthotropic elasticity, Hill's yield criterion and elasto-plasticity and contact algorithms, are capable of simulating complex contact between the tooth and the timber and between the base plate and the timber in a fastener. Using validated models, parametric studies of the double-sided nail plate joints was undertaken to cover the tooth length and the tooth width. Optimal configuration was assumed to have been attained when increase in nail plate tooth width did not result in a raise in joint capacity, in conjunction with the optimum tooth length. This paper presents the first attempt to model and optimise tooth profile of double-sided nail plate fastener timber joints, which offers rational designs of such fasteners.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.2
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• pp.244-248
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• 1995

Glomus tumor is uncommon tumor with an incidence of about 1% in soft tissue tumors and the single most common location is the subungual region of the finger. Many reports have emphasized that glomus tumors were difficult to diagnose and that the result of surgical removal was good, but nail deformity has received little attention. Most of authors removed the entire nail or partially splitted the nail to exposure the nail bed and tumor. Nobody reported whether nail deformity after operation was present or not. But, an abnormal nail is both a cosmetic and a functional problem in that catches on objects. In this study, our attention was postoperative nail deformity as well as the results of surgical removal. Seven patients(eight cases) who were diagnosed as a subungal glomus tumor in the hand were treated by surgical excision without removal of the nail and followed over twenty two months. And then we report on our experience with 8 cases of subungual glomus tumor which were successfully treated by complete excision without nail deformity.

• Clinics in Shoulder and Elbow
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• v.18 no.1
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• pp.47-51
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• 2015

Iatrogenic damage of the rotator cuff followed by postoperative shoulder function loss is a potential complication after antegrade intramedullary nailing (AIN) for a humeral fracture. The authors present a case of arthroscopic rotator cuff repair and subacromial decompression of a non-healed rotator cuff tendon (mainly supraspinatus) and secondary impingement syndrome caused either by the tear or a proud nail after AIN for a mid-shaft humeral fracture. At presentation, the patient complained of right shoulder pain and 'snapping', especially during forward elevation and abduction of the shoulder, of 4 years duration. Right shoulder pain started sometime after pain due to the humeral shaft fracture, operation had subsided, and persisted after nail removal. Arthroscopic findings showed a longitudinal rotator cuff tear at the nail entry point that had not healed and severe fibrous hypertrophy on the acromion underspace, which is a unique finding since most longitudinal splits of tendon fibers are more likely to heal than conventional rotator cuff tears detached from bone. The torn rotator cuff was repaired after debridement and placing side-to-side sutures. At his 34-month follow-up after rotator cuff repair, the patient showed complete recovery and had excellent clinical scores.

• Journal of Korean Foot and Ankle Society
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• v.12 no.1
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• pp.86-92
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• 2008

Purpose: To evaluate the safety and prognostic factors of intramedullary nailing of distal tibia fractures in terms of function and symptoms of the ankle joint. Materials and Methods: We retrospectively analyzed 22 distal tibial fractures with intramedullary nailing. The mean duration of follow-up was 43 months. We reviewed medical records to describe each case. We measured radiographic parameters such as fracture configuration, arthritic change of the ankle joint and status of reduction. We also assessed clinical results by AOFAS ankle hind foot scoring system, degree of pain by VAS and range of motion to find out prognostic factors for functional result of the ankle joint. Results: Bone healing was obtained in all cases without any wound complications. Mean AOFAS ankle score was 94. There were 4 cases with mild (VAS<3/10) ankle pain and 2 cases with mild limitation of ankle motion. The comminution of fracture had a significant relationship with delayed angular deformity of ankle joint (p=0.032). There was no other significant parameter affecting ankle joint function except the location of nail-end. Conclusion: Intramedullary nailing in distal tibia fracture is a safe and effective procedure. But further study may need to evaluate the relationship between the position of nail-end and the function of ankle joint.

• Journal of Korean Foot and Ankle Society
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• v.19 no.4
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• pp.171-175
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• 2015

Purpose: Tibiotalocalcaneal arthrodesis has been used as a treatment option for severe deformity including Charcot arthropathy, avascular necrosis of the talus, and severe osteoarthritis of the ankle and subtalar joint. The purpose of this study was to evaluate the result of the surgical outcome of tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail. Materials and Methods: Tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail was performed by one surgeon in 36 cases. Clinical and radiological finding was evaluated using assessment of fusion time, 5th metatarsal-tibial angle, possibility of postoperative complication, visual analogue scale for pain and American Orthopaedic Foot and Ankle Society (AOFAS) score. Results: Union was achieved in 33 cases at an average of 23 weeks (11~29 weeks). There were 3 cases of nonunion and 1 case of reoperation. Nail-tibial angle tended to be larger in nonunion cases. AOFAS score showed significantly poor outcome at malalignment (${\geq}5^{\circ}$), negative value of 5th metatarsal-tibial angle. Conclusion: Tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail is considered a useful treatment option for severe destruction and deformity involving ankle and subtalar joint.

• The Journal of the Korean bone and joint tumor society
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• v.18 no.2
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• pp.83-88
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• 2012

We reviewed the clinical features of 2 patients who underwent surgery for subungal exostosis, focusing on postoperative deformity of the nail. The lesion destroyed the nail bed and was excised with a direct approach. then thin split-thickness sterile matrix graft was done after excision of the tumor because the defect of the nail bed was large. Good postoperative appearance of the nail was obtained by thin split-thickness sterile matrix graft. The use of thin split-thickness sterile matrix graft for the replacement of a nail bed defect can regain a smooth, adherent, and normal-looking nail and avoid donor-site morbidity. Thin split-thickness toe-nail bed graft is a good choice for the prevention of postoperative deformity.

• Clinics in Shoulder and Elbow
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• v.17 no.3
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• pp.120-126
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• 2014

Background: To compare the treatment of the proximal humerus fracture using a Polarus nail or Philos plate, we aimed to analyze the functional recovery and the factors affecting the selection between the two types of surgery. Methods: The study included 107 patients with proximal humerus fracture who underwent surgery at our institution. Of these patients, 67 underwent surgery with Polarus nails (G1) and 40 with Philos plates (G2). In G1, the cases of two- and three-part fractures were 60 and 7 cases, in G2, the cases of two-, three-, and four-part fractures were 28, 10, and 2 cases, respectively. The average age was 61 years old, and the average follow-up period was 32.5 months. We compared radiological results, the functional recovery retrospectively. Results: The radiological union time was 6.8 weeks and 8.7 weeks on average in G1 and G2 (p < 0.05). At the one-year follow-up period, these were visual analogue scale (VAS) 1.355, forward flexion (FF) 130.968, external rotation (ER) 50.161, internal rotation (IR) L2 in G1, and VAS 0.781, FF 135.806 ER 51.25, IR L1 in G2, respectively, showing no significant differences between the two groups (p > 0.05). Similar observations were made at the final follow-up. In terms of functional recovery, no significant differences were seen at the one-year or at the final follow-up period (p > 0.05). Conclusions: For the surgical treatment of proximal humeral fracture, the selection of the type of surgery is affected by the fracture pattern. However, both methods give satisfactory outcomes and do not show significant differences in the functional outcome after the surgery.

• Journal of the Korean Wood Science and Technology
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• v.41 no.3
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• pp.211-220
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• 2013

The nailed joints in wood construction are commonly designed to resist and carry the lateral load but also subject to withdrawal force like uplift load due to the wind. This research was conducted to evaluate the performance of nailed joint composed of dimension lumber and sheathing materials through the nail withdrawal and unsymmetric double shear joint test, and then compared to current design values. The withdrawal strength was greatly dependant on wood specific gravity, and the withdrawal strength of I-joist with OSB showed higher value in spite of low specific gravity. The maximum withdrawal loads were greater than that of derived current design values about 5 times. The lateral resistance of Japanese larch/OSB nailed joints was higher than that of SPF/OSB nailed joint, and derived allowable lateral strength of nailed joints in this study exceeded the current design values. The failure mode of nailed joints was primarily due to the nail bending and this tendency was notable in SPF/OSB nailed joint.

• Journal of the Korean Wood Science and Technology
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• v.37 no.6
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• pp.524-530
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• 2009

In the post-beam structure, the infilled light-frame construction provides most shear strengths. Shear properties of the light-frame structure can be estimated from the shear properties of nailed connection for the sheathings, and those of nailed connections can be done from nail bending strengths. For the basic study to predict the yield strength and the slip modulus of a nailed sheathing shear wall, those of a nailed joint were examined from nail bending strengths. To estimate shear properties of a nailed connection, referenced bearing strength and bearing constant for the wood members and the experimental nail bending strengths of the helically threaded nail were applied. The yield strength using the diameter at grooves instead of shank diameter was well coincided with the experimental value, but the slip modulus was estimated much smaller. The effective factors, specific gravity for the main member, withdrawal by nail head diameter to the side member, and embedment and moment at the nail head were considered, and further examinations are needed for the precise prediction of the nailed connections.