• Structural Engineering and Mechanics
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• v.57 no.4
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• pp.717-731
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• 2016

In orthopedic surgery and more especially in total arthroplastie of hip, the fixing of the implants generally takes place essentially by means of constituted surgical polymer cement. The damage of this materiel led to the fatal rupture and thus loosening of the prosthesis in total hip, the effect of over loading as the case of tripping of the patient during walking is one of the parameters that led to the damage of this binder. From this phenomenon we supposed that a remain of bone is included in the cement implantation. The object of this work is to study the effect of this bony inclusion in the zones where the outside conditions (loads and geometric shapes) can provoke the fracture of the cement and therefore the aseptic lousing of the prosthesis. In this study it was assumed the presence of two bones -type inclusions in this material, one after we analyzed the effect of interaction between these two inclusions damage of damage to this material. One have modeled the damage in the cement around this bone inclusion and estimate the crack length from the damaged cement zone in the acetabulum using the finite element method, for every position of the implant under the extreme effort undergone by the prosthesis. We noted that the most intense stress position is around the sharp corner of the bone fragment and the higher level of damage leads directly the fracture of the total prosthesis of the hip.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.24-29
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• 2019

Purpose: To evaluate the characteristics and the risk factors of early onset subsequent vertebral compression fractures after percutaneous vertebroplasty. Materials and Methods: A total of 44 patients, who had a new subsequent vertebral fracture after percutaneous vertebroplasty for an osteoporotic vertebral compression fracture between January 2013 and December 2015, were recruited. The patients were divided into two groups according to the onset period of subsequent fracture. The number of patients who had a fracture within 3 months following vertebroplasty were 22 cases (Group A); after 3 months were 22 cases (Group B). Variables, including age, sex, bone mineral density (BMD), body mass index (BMI), preexisting vertebral compression fracture, location of the initial fracture, intradiscal cement leakage, injected cement volume, restoration of vertebral body height, and correction of kyphosis, in the two groups were analyzed and compared retrospectively. Results: The age, sex, BMD, BMI, preexisting vertebral compression fracture, location of the initial fracture, intradiscal cement leakage, and correction of kyphosis were similar in the two groups. Both a greater volume of bone cement injected and a greater degree of vertebral height restoration contributed significantly to the risk of fracture within 3 months. Conclusion: The cement volume and degree of height restoration are risk factors for early onset fracture at the adjacent vertebrae after percutaneous vertebroplasty and close attention is needed during the follow-up period.

• Journal of the Korean Orthopaedic Association
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• v.56 no.5
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• pp.445-449
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• 2021

Insertional bone cysts of the knee joint mainly appear in the form of small cysts at the bone attachment of the cruciate ligaments, and are usually not associated with symptoms. The authors report a 31-year-old man diagnosed with a huge insertional bone cyst connected to the femoral attachment of the posterior cruciate ligament in the knee joint, who obtained good results after curettage and bone cement filling.

• Journal of Trauma and Injury
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• v.28 no.3
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• pp.202-205
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• 2015

Purpose: Pulmonary cement embolization after vertebroplasty is a well-known complication. The reported incidence of pulmonary cement emboli after vertebroplasty ranges frome 2.1% to 26% with much of this variation resulting from which radiographic technique is used to detect embolization. Onset and severity of symptoms are variable. Case description: We present the case of a 83-year-old women who underwent fourth lumbar vertebroplasty and subsequently had dyspnea several days later. Posteroanterior chest radiography showed multiple linear densities. Computed tomography of thorax revealed also multiple bilateral, linear hyperdensities within the lobar pulmonary artery branches are detected in axial and coronal views. Literature Reviews: Operative management of vertebral compression fractures has included percutaneous vetebroplasty for the past 25 years. Symptoms of pulmonary cement embolism can occur during procedure, but more commonly begin days to weeks, even months, after vertebroplsty. Most cases of pulmonary cement emboli with cardiovascular and pulmonary complications are treated nonoperatively with anticoagulation. Endovascular removal of large cement emboli from the pulmonary arteries is not without risk and sometimes requires open surgery for complete removal of cement pieces. Conclusion: Pulmonary cement embolism is a potentially serious complication of vertebroplasty. If a patient has chest pain or respiratory difficulty after the procedure, chest radiography and possibly advanced chest imaging studies should be performed immediately.

• Structural Engineering and Mechanics
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• v.66 no.1
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• pp.37-43
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• 2018

In orthopedic surgery and in particular in total hip arthroplasty, the implant fixation is carried out using a surgical cement called polymethylmethacrylat (PMMA). This cement has to insure a good adhesion between implant and bone and a good load distribution to the bone. By its fragile nature, the cement can easily break when it is subjected to a high stress gradient by presenting a craze zone in the vicinity of inclusion. The focus of this study is to analyze the effect of inclusion in some zone of cement in which the loading condition can lead to the crack opening leading to their propagation and consequently the aseptic loosening of the THR. In this study, the fracture behavior of the bone cement including a strange body (bone remain) from which the onset of a crack is supposed. The effect of loading condition, the geometry, the presence of both crack and inclusion on the stress distribution and the fracture behavior of the cement. Results show that the highest stresses are located around the sharp tip of bony inclusion. Most critical cracks are located in the middle of the cement mantle when they are subjected to one leg standing state loading during walking.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.2
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• pp.112-118
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• 1997

Multicentric chondrosarcoma other than the mesenchymal subtype is rare separate entity. We experienced a case with nonmonomelic synchronous multicentric chondrosarcoma without any preexisting lesions of Oilier's disease or Maffucci's syndrome. To our knowledge, there was no report of synchronous nonmonomelic multicentric chondrosarcoma. A thirty-three year old man had right distal thigh pain of one and half year. Bone scan showed hot lesions on medial condyle of right femur and shaft of left femur. Plain X-ray showed osteolytic lesion on right femur and slight cortical thickening and calcific lesion was observed on left femoral shaft. Curettage and bone cement filling was done on both lesions. The pathology reports were grade I chondrosarcoma on both side of femur. At one month from operation, pathologic fracture of left femur occurred on bone cement-host bone junction. Conservative treatment and radiotherapy of 60Gy was done. At 8 months from operation, nonunion was evident. Segmental resection of left femur with contralateral fibula graft and second look operation on right condyle lesion were done. At 6 months from revision, fracture occurred at host-graft bone junction. We removed previous hardware and applied long DCP and massive autogenous bone graft. Afterwards, the patient looks good and union was progressing. But at 4 years from last operation, hypertrophic nonunion occurred. Another revision was done with condylar plate and bone graft and now he is well without any sign of local recurrence or metastasis.

• Structural Engineering and Mechanics
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• v.55 no.1
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• pp.93-109
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• 2015

Finite element analysis (FEA) combined with the concepts of linear elastic fracture mechanics (LEFM) provides a practical and convenient means to study the fracture and crack growth of materials. In this paper, a numerical modeling of crack propagation in the cement mantle of the reconstructed acetabulum is presented. This work is based on the implementation of the displacement extrapolation method (DEM) and the strain energy density (SED) theory in a finite element code. At each crack increment length, the kinking angle is evaluated as a function of stress intensity factors (SIFs). In this paper, we analyzed the mechanical behavior of cracks initiated in the cement mantle by evaluating the SIFs. The effect of the defect on the crack propagation path was highlighted.

• Journal of Korean Neurosurgical Society
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• v.51 no.2
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• pp.120-123
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• 2012

Objective : Percutaneous vertebroplasty (PVP) is usually carried out under three-dimensional (2D) fluoroscopic guidance. However, operative complications or bone cement distribution might be difficult to assess on the basis of only 2D radiographic projection images. We evaluated the feasibility of performing an intraoperative and postoperative examination in patients undergoing PVP by using three-dimensional (3D) reconstructive C-arm. Methods : Standard PVP procedures were performed on 14 consecutive patients by using a Siremobil Iso-$C^{3D}$ and a multidetector computed tomography machine. Post-processing of acquired volumetric datasets included multiplanar reconstruction (MPR) and surface shaded display (SSD). We analyzed intraoperative and immediate postoperative evaluation of the needle trajectory and bone cement distribution. Results : The male : female ratio was 2 : 12; mean age of patients, 70 (range, 77-54) years; and mean T score, -3.4. The mean operation time was 52.14 min, but the time required to perform and post-process the rotational acquisitions was 7.76 min. The detection of bone cement distribution and leakage after PVP by using MPR and SSD was possible in all patients. However, detection of the safe trajectory for needle insertion was not possible. Conclusion : 3D rotational image acquisition can enable intra- or post-procedural assessment of vertebroplasty procedures for the detection of bone cement distribution and leakage. However, it is difficult to assess the safe trajectory for needle insertion.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.1
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• pp.9-14
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• 2006

Purpose: The proximal tibial sarcoma patients, especially in their growing ages have problems of reconstruction. This study is to devise a methodology which can circumvent this limitations. Materials and Methods: Four cases of proximal tibial osteosarcoma underwent hemiarthroplasty. The mean age was 13 years (11~15) with a mean follow-up of 64 months (47~89). The procedure consists of ultrahigh molecular weight polyethylene (UHMWPE) liner as an substitute for the joint surface and this piece was fixed to the remaining tibial bone stock with Ender nail and bone cement. Results: Final functional score was 23.5 (78.3% of control) by MSTS criteria. All the cases showed stable joint without pain. Hemiarthroplasty related complications were absent. By saving the femoral physis, expected leg length discrepancy could be minimized by this procedure. Conclusions: Hemiarthroplasty of proximal tibia can be an option in pediatric sarcoma patients.

• Journal of the Korean Orthopaedic Association
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• v.55 no.1
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• pp.90-94
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• 2020

Percutaneous balloon kyphoplasty is an option for pain relief in pathological vertebral compression fractures. Complications related to cement leakage through cortical defects have been reported. On the other hand, dural compression due to retropulsion of the tumor mass is rarely reported. The authors report a case of a 65-year female patient who had cauda equina syndrome after a percutaneous balloon kyphoplasty in a pathological vertebral fracture, even though epidural compression were not found prior to surgery. Magnetic resonance imaging revealed retropulsion of the tumor mass into the spinal canal through the disrupted posterior vertebral cortex.