• Archives of Reconstructive Microsurgery
• /
• v.9 no.2
• /
• pp.114-119
• /
• 2000

The soft tissue defects including the Achilles tendon are complex and very difficult to reconstruct. Recently, several free composite flaps including the tendon have been used to reconstruct large defects in this area in an one-stage effort. Our case presents a patient reconstructed with free composite dorsalis pedis flap along with the extensor digitorum longus and superficial peroneal nerve for extensive defects of the Achilles tendon and surrounding soft tissue. A 36-year-old-man sustained an open injury to the Achilles tendon. He was referred to our department with gross infection of the wound and complete rupture of the tendon associated with loss of skin following reduction of distal tibial bone fracture. After extensive debridement, $6{\times}8cm$ of skin loss and 8cm of tendon defect was noted. Corresponding to the size of the defect, the composite dorsalis pedis flap was raised as a neurosensory unit including the extensor digitorum longus to provide tendon repair and sensate skin for an one-stage reconstruction. One tendon slip was sutured to the soleus musculotendinous portion, the other two were sutured to the gastrocnemius musculotendinous portion with 2-0 Prolene. The superficial peroneal nerve was then coaptated to the medial sural cutaneous nerve. The anterior tibial artery and vein were anastomosed to the posterior tibial artery and accompanying vein in an end to end fashion. After 12 months of follow-up, 5 degrees of dorsiflexion due to the checkrein deformity and 58 degrees of plantar flexion was achieved. The patient was able to walk without crutches. Twopoint discrimination and moving two-point discrimination were more than 1mm at the transferred flap site. The donor site healed uneventfully. Of the various free composite flaps for the Achilles tendon reconstruction when skin coverage is also needed, we recommand the composite dorsalis pedis flap. The advantages such as to control infection, adequate restoration of ankle contour for normal foot wear, transfer of the long tendinous portion, and protective sensation makes this flap our first choice for reconstruction of soft tissue defect including the Achilles tendon.

• Journal of Korean Foot and Ankle Society
• /
• v.20 no.1
• /
• pp.6-11
• /
• 2016

Flatfoot deformity, defined as loss of medial longitudinal arch, sometimes involves symptoms such as medial arch pain or Achilles tendon tightening, etc. Whether the etiology of deformity is congenital or acquired, i.e., posterior tibial tendon dysfunction, symptoms are largely resolved with conservative treatment including medication, orthoses, and activity modification. Surgery should be considered in cases of failure of conservative treatment and clinicians can select an appropriate technique among many surgical options including calcaneal osteotomy or flexor digitorum longus tendon transfer. Principles of corrective surgery include the recovery of alignment and the preservation of joint motion.

• Archives of Reconstructive Microsurgery
• /
• v.5 no.1
• /
• pp.128-136
• /
• 1996

Radial nerve injury is caused by variety of etiologies, mainly traumatic. It is primarily a motor nerve and loss of it's function leads to a significant disability. Surgical treatments of radial nerve comprise of neurolysis(internal or external), neurorrhaphy(eineural, perineural or epi-perineural), nerve graft and tendon transfer. However, there is still controversies in treatment methods and time of operation. Authors experienced 23 cases of radial nerve injuries who were treated by operative methods and followed up over 1 year's duration. The male to female ratio was 18 to 5 and mean age was 30.7 years old. The causes were 13 cases in fractures, 5 cases in crushing injury, 3 cases in laceration, 1 case in CO poisoning and 1 case in unknown cause. The summary of the study were as follows ; 1. Excellent or good results were obtained in overall 16 cases among 23 cases; 5 of 9 cases in neurolysis, 3 of 3 cases in neurorrhaphy, 2 of 3 cases in nerve graft and 6 of 8 cases in tendon transfer. 2. In cases of neurorrhaphy and nerve graft, primary or delayed repair showed excellent or good results and neurolysis performed before 6 months leads to better results. But there was no correlations between the time of injury and operation in tendon transfer. 3. The radial nerve injury associated with extensive soft tissue defect or any conditions that leads to nerve ischemia results poor prognosis. 4. The patients aged under 40 years showed better prognosis in clinical results according to the age of surgical treatment. 5. If the surgeon decide the method and the time of operation through the exact evaluation of the factors which influencing the end result such as age of the patient, level and type of injury, extent of nerve lesion and the associated tissue injury, good result could be expected.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.6 no.4
• /
• pp.336-341
• /
• 2018

The prestressing force introduced to the tendon in pretensioned concrete members is transferred by direct bond between tendon and concrete, which requires a proper estimation of stress transfer length. The use of pretensiond and/or precast members with UHPC (Ultra High Performance Concrete) may give many advantages in quality control. This paper presents an experiment to estimate the stress transfer length of UHPC for various compressive strength levels of UHPC, cover depths, diameters of tendons and tensioning forces. According to the result of this experiment, the stress transfer length of UHPC member is much reduced comparing that of normal strength concrete. The reduction in stress transfer length of UHPC may come from the high bond strength capacity of UHPC. The transfer lengths obtained from this experiment are compared to those in current design code and a new formula is proposed.

• Journal of the Korea Concrete Institute
• /
• v.20 no.6
• /
• pp.697-704
• /
• 2008

This paper presents an analytical prediction of Nonlinear characteristics of prestressed concrete bridges by strengthened of externally tendon considering construction sequence, using unbonded tendon element and beam-column element based on flexibility method. Unbonded tendon model can represent unbounded tendon behavior in concrete of PSC structures and it can deal with the prestressing transfer of posttensioned structures and calculate prestressed concrete structures more efficiently. This tendon model made up the several nodes and segment, therefore a real tendon of same geometry in the prestressed concrete structure can be simulated the one element. The beam-column element was developed with reinforced concrete material nonlinearities which are based on the smeared crack concept. The fiber hysteresis rule of beam-column element is derived from the uniaxial constitutive relations of concrete and reinforcing steel fibers. The formulation of beam-column element is based on flexibility. Beam-column element and unbonded tendon element were be involved in A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), that were used the analysis of RC and PSC structures. The proposed numerical method for prestressed concrete structures by strengthened of externally tendon is verified by comparison with reliable experimental results.

• Journal of the Korean Arthroscopy Society
• /
• v.13 no.3
• /
• pp.212-219
• /
• 2009

Medially retracted large-sized rotator cuff tears includes large-sized tears, massive tears and irreparable tears. Generally arthroscopic repair or open repair of rotator cuff tears is used in reparable tears. However, arthroscopic repair requires long period practice and endurance. In irreparable tears, arthroscopic debridement, partial repair, latissimus dorsi transfer and retrograde arthroplasty can be the option. Arthoscopic debridement gives temporal relief who experienced improvement in pain and increase in range of motion after subacromial local anesthetic injection. Also arthroscopic partial repair gives good results in irreparable cases, especially in suprascapular nerve traction neurapraxia. Tendon transfer can be used in mild to moderate muscle weakness in shoulder abduction for long term treatment. Pectoralis major transfer can be used in anterosupeior tears and latissimus dorsi transfer can be used in posterosuperior tears. Reverse shoulder prosthesis is used in extreamly weakened shoulder pseudoparalysis. The authors discussed the method of arthroscopic repair in irreparable tears. The debridement, partial repair, and tendon transfer could be used in medially retracted large-sized rotator cuff tears.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.583-584
• /
• 2009

This is an experimental study of test parameters that have not been fully covered by previous researches in order to estimate more accurate transfer length of pretensioned, prestressed concrete members.

• 대한미세수술학회:학술대회논문집
• /
• 1996.10a
• /
• pp.169-170
• /
• 1996

• Computers and Concrete
• /
• v.31 no.4
• /
• pp.337-348
• /
• 2023

Shear wall is commonly used as a lateral force resisting system of concrete mid-rise and high-rise buildings, but it brings challenges in providing relatively large space throughout the building height. For this reason, the structure system where the upper structure with bearing, non-bearing and/or shear walls that sits on top of a transfer plate system supported by widely spaced columns at the lower stories is preferred in some regions, particularly in low to moderate seismic regions in Asia. A thick reinforced concrete (RC) plate has often been used as a transfer system, along with RC transfer girders; however, the RC plate becomes very thick for tall buildings. Applying the post-tensioning (PT) technique to RC plates can effectively reduce the thickness and reinforcement as an economical design method. Currently, a simplified model is used for numerical modeling of PT transfer plate, which does not consider the interaction of the plate and the upper structure. To observe the actual behavior of PT transfer plate under seismic loads, it is necessary to model whole parts of the structure and tendons to precisely include the interaction and the secondary effect of PT tendons in the results. This research evaluated the seismic behavior of shear wall-type residential buildings with PT transfer plates for the condition that PT tendons are included or excluded in the modeling. Three-dimensional finite element models were developed, which includes prestressing tendon elements, and response spectrum analyses were carried out to evaluate seismic forces. Two buildings with flat-shape and L-shape plans were considered, and design forces of shear walls and transfer columns for a system with and without PT tendons were compared. The results showed that, in some cases, excluding PT tendons from the model leads to an unrealistic estimation of the demands for shear walls sit on transfer plate and transfer columns due to excluding the secondary effect of PT tendons. Based on the results, generally, the secondary effect reduces shear force demand and axial-flexural demands of transfer columns but increases the shear force demand of shear walls. The results of this study suggested that, in addition to the effect of PT on the resistance of transfer plate, it is necessary to include PT tendons in the modeling to consider its effect on force demand.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.4A
• /
• pp.279-286
• /
• 2011

FRP (Fiber Reinforced Polymer) tendons can be used as an alternative to solve the corrosion problem of steel tendons. Material properties of FRP tendons-bond strength, transfer length, development length-must be determined in order to apply to concrete structures. First of all, in case of application for pretension concrete members with CFRP tendons, transfer length is an important characteristic. The bond of the material characteristics should be demanded clearly to apply to PSC structures prestressed with FRP tendons. This paper investigated on the bond characteristics of FRP reinforcements with various surface-type. To determine the bond characteristics of FRP materials used in place of steel reinforcement or prestressing tendon in concrete, pull-out testing suggested by CAN/CSA S806-02 was performed. A total of 40 specimens were made of concrete cube with steel strands, deformed steel bar and 6 different surface shape FRP materials like carbon or E-glass. Results of the bonding tests presented that each specimen showed various behaviors as the bond stress-slip curve and compared with the bond characteristic of CFRP tendon developed in Korea.