JaLCDOI 10.18926/AMO/53680
FullText URL 69_5_325.pdf
Author Okada, Yoshiki| Endo, Hirosuke| Mitani, Shigeru| Fujiwara, Kazuo| Tetsunaga, Tomonori| Kagawa, Yohei| Fujii, Yosuke| Kunisada, Toshiyuki| Ozaki, Toshifumi|
Abstract Total hip arthroplasty (THA) is the most effective treatment for advanced or end-stage hip osteoarthritis. However, venous thromboembolism (VTE) remains one of its unresolved complications. We reviewed the records of 322 patients undergoing primary THA and investigated the efficacy of anticoagulant prophylaxis for VTE. Our study cohort consisted of 60 patients who received no anticoagulants, 100 patients who received a factor Xa inhibitor (fondaparinux), 100 patients who received low molecular weight heparin (enoxaparin), and 62 patients who selectively received no anticoagulant prophylaxis due to perioperative bleeding, weight, and/or hemoglobin concentration. Enhanced 64-slice multidetector row computed tomography was performed postoperatively for 7 days in all cases. The incidence of VTE in the four groups was 15%, 9.0%, 6.0%, and 6.4%, respectively. The incidence of VTE was significantly lower in the groups receiving anticoagulant prophylaxis and the group selectively receiving no anticoagulant prophylaxis than in the group receiving no anticoagulants. Complications of fondaparinux therapy included hepatic dysfunction in 4 cases (4.0%), minor bleeding in 2 cases (2.0%), persistent wound drainage in 3 cases (3.0%), and eruption in 1 case (1.0%). The complications of enoxaparin therapy were persistent wound drainage in 1 case (1.0%) and progression of anemia in 1 case (1.0%). The incidence of VTE was low in patients who selectively received no anticoagulant prophylaxis, so we conclude that anticoagulant prophylaxis should be used selectively in THA cases.
Keywords total hip arthroplasty venous thromboembolism anticoagulant prophylaxis complications
Amo Type Erratum
Published Date 2015-10
Publication Title Acta Medica Okayama
Volume volume69
Issue issue5
Publisher Okayama University Medical School
Start Page 325
End Page 325
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2015 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 26490031
Related Url http://doi.org/10.18926/AMO/53556
JaLCDOI 10.18926/AMO/53556
FullText URL 69_4_205.pdf
Author Okada, Yoshiki| Endo, Hirosuke| Mitani, Shigeru| Fujiwara, Kazuo| Tetsunaga, Tomonori| Kagawa, Yohei| Fujii, Yosuke| Kunisada, Toshiyuki| Ozaki, Toshifumi|
Abstract Total hip arthroplasty (THA) is the most effective treatment for advanced or end-stage hip osteoarthritis. However, venous thromboembolism (VTE) remains one of its unresolved complications. We reviewed the records of 322 patients undergoing primary THA and investigated the efficacy of anticoagulant prophylaxis for VTE. Our study cohort consisted of 60 patients who received no anticoagulants, 100 patients who received a factor Xa inhibitor (fondaparinux), 100 patients who received low molecular weight heparin (enoxaparin), and 62 patients who selectively received no anticoagulant prophylaxis due to perioperative bleeding, weight, and/or hemoglobin concentration. Enhanced 64-slice multidetector row computed tomography was performed postoperatively for 7 days in all cases. The incidence of VTE in the four groups was 15オ, 9.0オ, 6.0オ, and 6.4オ, respectively. The incidence of VTE was significantly lower in the groups receiving anticoagulant prophylaxis and the group selectively receiving no anticoagulant prophylaxis than in the group receiving no anticoagulants. Complications of fondaparinux therapy included hepatic dysfunction in 4 cases (4.0オ), minor bleeding in 2 cases (2.0オ), persistent wound drainage in 3 cases (3.0オ), and eruption in 1 case (1.0オ). The complications of enoxaparin therapy were persistent wound drainage in 1 case (1.0オ) and progression of anemia in 1 case (1.0オ). The incidence of VTE was low in patients who selectively received no anticoagulant prophylaxis, so we conclude that anticoagulant prophylaxis should be used selectively in THA cases.
Keywords total hip arthroplasty venous thromboembolism anticoagulant prophylaxis complications
Amo Type Original Article
Published Date 2015-08
Publication Title Acta Medica Okayama
Volume volume69
Issue issue4
Publisher Okayama University Medical School
Start Page 205
End Page 212
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2015 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 26289911
Web of Sience KeyUT 000365519100003
Related Url http://doi.org/10.18926/AMO/53680
JaLCDOI 10.18926/AMO/52008
FullText URL 67_6_351.pdf
Author Yokoyama, Yusuke| Abe, Nobuhiro| Fujiwara, Kazuo| Suzuki, Masahiko| Nakajima, Yoshikazu| Sugita, Naohiko| Mitsuishi, Mamoru| Nakashima, Yoshio| Ozaki, Toshifumi|
Abstract A computer-assisted navigation system to be used for total knee arthroplasties (TKAs) was reported to improve the accuracy of bone resection and result in precise implant placement, but the concomitant surgical invasion and time consumption are clinical problems. We developed a computed tomography (CT)-based navigation system (NNS) to be used for minimally invasive TKA. It requires only the reference points from a small limited area of the medial femoral condyle and proximal tibia through a skin incision to obtain optical images. Here we evaluated the usefulness and accuracy of the NNS in comparison with the commercially available BrainLAB image-free navigation system (BLS). In a clinical experiment, the registration times obtained with the NNS tended to be shorter than those obtained with the BLS, but not significantly so. The NNS group tended to be in the extended position in the sagittal plane of the distal femur within 3 degrees, and the BLS group showed rather flexed deviation in the sagittal plane of the anterior femur.
Keywords total knee arthroplasty navigation system minimally invasive surgery
Amo Type Original Article
Published Date 2013-12
Publication Title Acta Medica Okayama
Volume volume67
Issue issue6
Publisher Okayama University Medical School
Start Page 351
End Page 358
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2013 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 24356719
Web of Sience KeyUT 000328915700003
Related Url http://ousar.lib.okayama-u.ac.jp/metadata/52515
JaLCDOI 10.18926/AMO/48965
FullText URL 66_5_409.pdf
Author Sarai, Takaaki| Inoue, Takayuki| Fujiwara, Kazuo| Kuramoto, Koichi|
Abstract The human femur is subjected to an impulsive load at its distal end during daily life. Femoral bone fracture caused by impact loading is common in elderly women. It is important to clarify the dynamic response of the femur and to evaluate the change in its stress state during impact loading. A 3-dimensional model of the femur was prepared in the present study, and the impulsive stress waves propagating from the distal end of the femur were analyzed by the dynamic finite element method. This model showed that the von Mises equivalent stress is large on the anterior and posterior sides of the mid-diaphysis when the impact direction is different from that of the bone axis. As for the femoral neck, the absolute value of minimum principal stress initially increases on the medial side;slightly later the maximum principal stress increases on the lateral side. In this case, the absolute value of the maximum principal stress was found to be larger than that of the minimum principal stress, and the absolute value of the principal stress decreased as the impact angle increased. Further, the femoral neck and the trochanter were shown to have a higher risk of bone fracture when the impact direction is coincident with the bone axis.
Keywords biomechanics femur impulsive stress wave impact angle dynamic finite element analysis
Amo Type Original Article
Published Date 2012-10
Publication Title Acta Medica Okayama
Volume volume66
Issue issue5
Publisher Okayama University Medical School
Start Page 409
End Page 415
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2012 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 23093059
Web of Sience KeyUT 000310253900005
Author Fujiwara, Kazuo| Endo, Hirosuke| Miyake, Yoshiaki| Ozaki, Toshifumi|
Published Date 2010-08-02
Publication Title 岡山医学会雑誌
Volume volume122
Issue issue2
Content Type Journal Article
JaLCDOI 10.18926/AMO/30974
FullText URL fulltext.pdf
Author Ikuma, Hisanori| Abe, Nobuhiro| Uchida, Youichiro| Furumatsu, Takayuki| Fujiwara, Kazuo| Nishida, Keiichiro| Ozaki, Toshifumi|
Abstract <p>Instability of the knee after the medial collateral ligament (MCL) injury is usually assessed with the manual valgus stress test, even though, in recent years, it has become possible to apply magnetic resonance imaging (MRI) to the assessment of the damage of the ligament. The valgus instability of 24 patients (12 isolated injuries and 12 multiple ligament injuries) who suffered MCL injury between 1993 and 1998 was evaluated with the Hughston and Eilers classification, which involves radiographic assessment under manual valgus stress to the injured knees. We developed a novel system for classifying the degree of injury to the MCL by calculating the percentage of injured area based on MRI and investigated the relationship between this novel MRI classification and the magnitude of valgus instability by the Hughston and Eilers classification. There was a significant correlation between the 2 classifications (p=0.0006). On the other hand, the results using other MRI based classification systems, such as the Mink and Deutsch classificaiton and the Petermann classification, were not correlated with the findings by the Hughston and Eilers classification in these cases (p0.05). Since MRI is capable of assessing the injured ligament in clinical practice, this novel classification system would be useful for evaluating the stability of the knee and choosing an appropriate treatment following MCL injury.</p>
Keywords medial collateral ligament magnetic resonance imaging knee instability novel method
Amo Type Original Article
Published Date 2008-06
Publication Title Acta Medica Okayama
Volume volume62
Issue issue3
Publisher Okayama University Medical School
Start Page 185
End Page 191
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 18596835
Web of Sience KeyUT 000257130300006
JaLCDOI 10.18926/AMO/30721
FullText URL fulltext.pdf
Author Inoue, Atsushi| Asaumi, Koji| Endo, Hirosuke| Fujiwara, Kazuo| Mitani, Shigeru| Ozaki, Toshifumi|
Abstract The present retrospective study assessed radiographs to determine socket wear in total hip arthroplasty (THA) with 22-mm zirconia or COP (Cobalt-Chrome alloy rich in Cobalt and Phosphorous) heads, and in cemented stems at more than 10 years after operation. Sockets of ultra high molecular weight polyethylene were used in each of two THA groups (13 hips each) in a clinical trial in our hospital between 1989 and 1990. Three observers carried out masked assessments of the radiographs. Upon fi nal examination, there was no remarkable loosening in the zirconia or COP group, and no case had required revision surgery as of 2005. There was a statistically signifi cant diff erence between the 2 groups in average annual linear wear, at 0.093 mm/year and 0.046 mm/year in the zirconia and COP groups, respectively. Volume wear and average annual volume wear were also signifi cantly greater in the zirconia group despite its superior mechanical strength and toughness in vitro. Our present fi ndings do not confi rm early expectations of lower wear in long-term results of 22-mm zirconia femoral heads used in THA.
Keywords total hip arthroplasty zirconia head COP head polyethylene wear
Amo Type Original Article
Published Date 2006-12
Publication Title Acta Medica Okayama
Volume volume60
Issue issue6
Publisher Okayama University Medical School
Start Page 311
End Page 318
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 17189974
Web of Sience KeyUT 000243019000002