• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.389-392
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• 2004

It is clinically well known that pre-tension of wires increases the fracture stability in ring or hybrid external fixation. In some cases, additional half pin should be necessary to increase the stability when soft tissue impalement occurs during fixation. In this paper, the fracture stability of a hybrid external fixator system with different pre-tension effects and additional half-pins was analysed using FEM to investigate the effects of these pre-tension and half pin on the system stability quantitatively. 3-D finite element models of five different fixator frames were developed using by beam elements. In axial compression analysis, the fracture stiffness was increased maximally 62％ as the pre-tension increased. In torsion analysis, in the other hand, there is little variations in the fracture stiffness. Additional half pin increased the system stiffness about 200 ％. From the results, proper pre-tension and additional half pin would provide good methods to increase the fracture stability of the hybrid external fixator and provide more surgical options to minimize soft tissue damage at the fracture site.

• Journal of Korean Foot and Ankle Society
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• v.15 no.4
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• pp.187-194
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• 2011

Ankle injuries may involve the distal tibiofibular syndesmosis and can be associated with a variable degree of trauma to the soft tissue and osseous structures that play an important role in ankle joint stability. Ankle syndesmotic injury may occur solely as a soft tissue injury or in association with variable ankle fractures. Ankle syndesmotic injury does not necessarily lead to ankle instability; however, the coexistence of deltoid ligament injury critically destabilizes the ankle joint. The prevalence of these injuries may be higher than previously reported. The diagnosis of syndesmotic injury as not always easy because isolated ankle sprains may be missed in the absence of a frank diastasis and syndesmotic instability may be unnoticed in the presence of bimalleolar ankle fractures. Controversies arise at almost every phase of treatment includings : type of fixation(screw size, type of implant), number of cortices required for fixation and of need for hardware removal. Regardless of controversies, the most important goal should be restore and maintain the normal tibiofibular relationship to allow for healing of the ligamentous structures of the syndesmosis.

• Journal of Korean Foot and Ankle Society
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• v.9 no.1
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• pp.87-93
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• 2005

Purpose: We conducted this study to examine the clinical results of the proximal metatarsal wedge osteotomy using a single screw fixation and the distal soft tissue procedure in patients with moderate to severe hallux valgus deformity. Materials and Methods: Between February 2002 and February 2004, we performed these procedures on 12 patients (15 cases). The 6 cases of all patients had mild to moderate instability in the first MTC (metatarsocuneiform) joint. We estimated the clinical outcomes, the radiological findings and complications. Results: AOFAS score was improved from preoperative 41.5 points to 87.7 points lastly on average. The mean correction angle of HVA and IMA was $23.8^{\circ}$ and $6.6^{\circ}$, respectively. The mean position of tibial sesamoid was 2.67 before surgery and 0.87 after surgery. The mean shortening of the first metatarsal bone was 3.07 mm after surgery. There was no pain and complications on the first MTC joint except the breakage of screw in one case and instability of the first MTC joint was improved postoperatively. Conclusion: We obtained good clinical and radiographic outcomes in our series. So, proximal metatarsal wedge osteotomy using a single screw fixation and distal soft tissue procedure seems one of the good surgical treatments for moderate hallux valgus deformity.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.37.1-37.7
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• 2018

Background: Fibrous dysplasia (FD) is characterized by the replacement of normal bone by abnormal fibro-osseous connective tissue and typically treated with surgical contouring of the dysplastic bone. When dysplastic lesions involve occlusion, not only is surgical debulking needed, orthognathic surgery for correction of dentofacial deformity is mandatory. However, the long-term stability of osteotomized, dysplastic bone segments is a major concern because of insufficient screw-to-bone engagement during surgery and the risk of FD lesion re-growth. Case presentation: This case report reviewed two patients with non-syndromic FD that presented with maxillary occlusal canting and facial asymmetry. Le Fort I osteotomy with recontouring of the dysplastic zygomaticomaxillary region had been performed. The stability of osseous segments were favorable. However, dysplastic, newly formed bone covered the previous plate fixation site and mild bony expansion was observed, which did not influence the facial profile. Including the current cases, 15 cases of orthognathic surgery for FD with dentition have been reported in the literature. Conclusion: The results showed that osteotomy did not appear to significantly reduce the long-term stability of the initial fixation insufficiency of the screw to the dysplastic bone. However, based on our results and those of the others, long-term follow-up and monitoring are needed, even in cases where the osteotomized segment shows stable results.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.381-388
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• 2020

The quality control of pathological specimens is important for accurate molecular pathology testing. This study evaluated that specimen factors affecting the DNA quality during tissue processing and sample types for BRAF, EGFR, and KRAS mutations tests. One thousand seven hundred and seventy-two molecular pathology tests were investigated for the factors influencing the DNA quality, such as sample type, formalin fixation time, and reexamination status. Cytology samples stored in a saline solution had better DNA quality than commercial cytology preservation. Tissue samples fixed in formalin within 24 hours had better DNA quality than the samples fixed over 24 hours. Between the types of samples, fresh tissue samples and tissue samples with a high tumor cell density had relatively better DNA quality than the formalin-fixed paraffin-embedded (FFPE) tissues and cytology specimens. Of real-time PCR, the non-PNA Ct value increased proportionally with samples held for longer than 24 hours in formalin, and that the formalin-fixed time affects the sample DNA quality. In conclusion, the appropriate tumor cellularity and 10% neutral formalin fixation time are the most important factors for maintaining the DNA quality. These factors should be managed properly for an accurate pathological molecular test to ensure optimal DNA quality.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.33-37
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• 2009

Purpose: To evaluate the results of the compression plate fixation and autogenous bone graft in the management of humerus shaft nonunion. Materials and Methods: Eighteen cases were treated for humerus shaft nonunion using compression plate fixation and an autogenous iliac bone graft. The mean follow-up period was 28 months. Bony union was confirmed from the serial radiographs and the clinical outcomes were assessed according to ASES scoring system. Results: In 12 cases of initial plate fixation, the causes of nonunion were 6 cases of inadequate plate length, 2 with a broken plate, 2 with screw loosening, 1 infection and 1 noncompliance of a psychiatric patient. In 3 cases of initial intramedullary fixation, the cause of nonunion was a distraction of the fracture site. In 3 cases of external fixation, the cause of nonunion was inadequate fixation. All cases showed bony union after an average of 24 weeks. The clinical outcomes were 11 excellent, 6 good and 1 fair. Conclusion: In the treatment for nonunion, compression plate fixation with autogeneous bone graft after complete removal of the fibrous and necrotic tissue is believed to give satisfactory results.

• Archives of Reconstructive Microsurgery
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• v.16 no.1
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• pp.6-13
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• 2007

Purpose: To report the clinical results of the vascularized fibular graft in the treatment of intractable infected nonunion of femur. Materials and Methods: We reviewed 3 patients who were performed vascularized fibular graft in treated for intractable infected nonunion of femur. They had received an average of 5.6 times($4{\sim}8\;times$) surgical treatment at different hospitals. 1 case was of a infected nonunion in a fracture treated with internal fixation, the fracture having occurred after resection of a malignant tumor and transplantation of pasteurized autologous bone. 2 cases occurred after internal fixation in closed fractures. Surgical treatment was performed an average of 4 times($3{\sim}5\;times$) at our hospital and in all of the cases debridement of necrotic tissue and sequestrectomy. And vascularized fibular graft was performed. In all cases unilateral external fixation devices were used, of these, 1 case was changed into internal fixation. The final conclusion was made by assessment of functional outcomes and complications according to the standards of Paley. Results: As a result, in all of the cases bone union was achieved, and in the last follow up the functional results were excellent in 2 cases and good in 1 case. There were not presented leg length discrepancy of more than 2 cm, and further loss of knee joint motion. After previous treatment, average 23.3 months($16{\sim}30\;months$) was taken to eliminate infection and achieve complete bone union via vascularized fibular graft in our hospital. Conclusion: In treatment of intractable infected nonunion of femur, fairly good results can be expected after firm fixation, through debridement and vascularized fibular graft.

• Journal of Korean Dental Science
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• v.2 no.2
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• pp.24-30
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• 2009

Two component orthodontic C-implants have been introduced as intermaxillary fixation (IMF) screws in cases of periodontal problems with bone loss, severely damaged teeth, or short roots. This retrospective research sought to investigate the complications and risk factors associated with the failure of two-part C-implants for IMF cases and to show the possible indications compared to one-component mini-implants. The study sample consisted of 46 randomly selected patients who had a total of 203 implants. Pearson chi-square tests of independence were used to test for associations among categorical variables. At least 19 of the total 203 implants failed (9.3%). There was no significant difference in implant failure due to gender, oral hygiene, and placement, although a significant difference due to soft tissue characteristics and root contact was observed. The two-component design of the mini-implant is reliable for difficult IMF cases. Note, however, that the factors influencing implant failure were found to be age, root damage, and condition of soft tissues.

• Clinics in Shoulder and Elbow
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• v.20 no.4
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• pp.236-239
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• 2017

After dual plating with a locking compression plate for comminuted intraarticular fractures of the distal humerus, the incidence of ulnar nerve injury after surgery has been reported to be up to 38%. This can be reduced by an anterior transposition of the ulnar nerve but some surgeons believe that extensive handling of the nerve with transposition can increase the risk of an ulnar nerve dysfunction. This paper reports ulnar nerve injuries caused by the incomplete insertion of a screw head in dual plating without an anterior ulnar nerve transposition for AO/OTA type C2 distal humerus fractures. When an anatomical locking plate is applied to a distal humeral fracture, locking screws around the ulnar nerve should be inserted fully without protrusion of the screw because an incompletely inserted screw can cause irritation or injury to the ulnar nerve because the screw head in the locking system usually has a slightly sharp edge because screw head has threads. If the change in insertion angle and resulting protruded head of the screw are unavoidable for firm fixation of fracture, the anterior transposition of the ulnar nerve is recommended over a soft tissue shield.

• Archives of Plastic Surgery
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• v.42 no.5
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• pp.580-587
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• 2015

Background Descent of the lateral aspect of the brow is one of the earliest signs of aging. The purpose of this study was to describe an open surgical technique for lateral brow lifts, with the goal of achieving reliable, predictable, and long-lasting results. Methods An incision was made behind and parallel to the temporal hairline, and then extended deeper through the temporoparietal fascia to the level of the deep temporal fascia. Dissection was continued anteriorly on the surface of the deep temporal fascia and subperiosteally beyond the temporal crest, to the level of the superolateral orbital rim. Fixation of the lateral brow and tightening of the orbicularis oculi muscle was achieved with the placement of sutures that secured the tissue directly to the galea aponeurotica on the lateral aspect of the incision. An additional fixation was made between the temporoparietal fascia and the deep temporal fascia, as well as between the temporoparietal fascia and the galea aponeurotica. The excess skin in the temporal area was excised and the incision was closed. Results A total of 519 patients were included in the study. Satisfactory lateral brow elevation was obtained in most of the patients (94.41%). The following complications were observed: total relapse (n=8), partial relapse (n=21), neurapraxia of the frontal branch of the facial nerve (n=5), and limited alopecia in the temporal incision (n=9). Conclusions We consider this approach to be a safe and effective procedure, with long-lasting results.