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 Science KeyUT 000243019000002
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 Science KeyUT 000328915700003
Related Url http://ousar.lib.okayama-u.ac.jp/metadata/52515
JaLCDOI 10.18926/AMO/60373
FullText URL 74_4_345.pdf
Author Tanaka, Takaaki| Furumatsu, Takayuki| Hiranaka, Takaaki| Okazaki, Yuki| Masudaa, Kenji| Senoa, Noritaka| Ozaki, Toshifumi|
Abstract The aim of this study was to evaluate tunnel coalition and inter-tunnel distance by comparing the tibial tunnel position in double-bundle anterior cruciate ligament (ACL) reconstruction performed with a conventional guide versus a posterolateral (PL) divergence (PLD) guide. Subjects were 43 patients (ACL tip aimer: 20 knees; PLD guide: 23 knees) who underwent double-bundle ACL reconstruction between September 2014 and December 2017. In all cases, the tibial tunnel position, tunnel edge distance and tunnel angles were evaluated based on CT images. Clinical outcome was evaluated using the Lachman test, pivot-shift test, and Lysholm score. Tibial tunnel positions were similar between the conventional and PLD guide groups, while tibial tunnel edge distance was significantly less in the conventional group. Tunnel coalition was observed in 5 knees in the conventional and no knees in the PLD guide group. Distance between two tibial tunnel centers was 9.1 mm for the tip aimer, and 10.5 mm for the PLD guide. Creation of the PL tunnel tended to involve insertion from a more medial aspect for the PLD guide group than the conventional guide group. No differences in clinical outcomes were noted. The PLD guide can be used to create anatomically-positioned PL tunnels, and reduce the probability of occurrence of tunnel coalition.
Keywords anterior cruciate ligament reconstruction tibial tunnel position PL divergence guide tunnel coalition
Amo Type Original Article
Published Date 2020-08
Publication Title Acta Medica Okayama
Volume volume74
Issue issue4
Publisher Okayama University Medical School
Start Page 345
End Page 350
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2020 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 32843766
Web of Science KeyUT 000562508700010
NAID 120006880212
JaLCDOI 10.18926/AMO/30972
FullText URL fulltext.pdf
Author Endo, Hirosuke| Asaumi, Koji| Mitani, Shigeru| Noda, Tomoyuki| Minagawa, Hiroshi| Tetsunaga, Tomonori| Ozaki, Toshifumi|
Abstract <p>A minimally invasive plate osteosynthesis technique using a locking compression plate (LCP) has been used widely in trauma cases. Its advantages are that the MIPO technique does not interfere with the fracture site and thus provides improved biological healing, and that the LCP has excellent angular stability. Its use in bone lengthening, however, has not been established. In such cases, it is desirable to shorten the external skeletal fixation period as much as possible. Here, the MIPO technique using an LCP was applied to femoral distraction osteogenesis in an attempt to shorten the external skeletal fixation period. For femoral lengthening, the MIPO technique was performed in 2 stages. Orthofix external fixators (Orthofix, England) were used to insert screws from the anterolateral side rather than from the lateral side of the femur for bone lengthening. When sufficient callus formation was detected postoperatively at the site of bone lengthening, and the absence of infection was ensured, limb draping was performed, including a whole external fixator, and then the MIPO technique was applied with an LCP. In 3 cases (5 limbs), the average duration of external skeletal fixation was 134days, the average external-fixation index was 24days/cm, and the average consolidation index was 22days/cm. The MIPO technique using an LCP made it possible to shorten the external skeletal fixation-wearing period in femoral lengthening.</p>
Keywords femoral lengthening minimally invasive plate osteosynthesis locking compression plate external skeletal fixation external-fixation index
Amo Type Original Article
Published Date 2008-10
Publication Title Acta Medica Okayama
Volume volume62
Issue issue5
Publisher Okayama University Medical School
Start Page 333
End Page 339
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 18985094
Web of Science KeyUT 000260391300008
JaLCDOI 10.18926/AMO/32853
FullText URL fulltext.pdf
Author Endo, Hirosuke| Noda, Tomoyuki| Mitani, Shigeru| Nakahara, Ryuichi| Tetsunaga, Tomonori| Kunisada, Toshiyuki| Ozaki, Toshifumi|
Abstract <p>Femoroacetabular impingement (FAI) is a condition characterized by the impingement of the femur and acetabulum. In Japan, this disorder has become recognized gradually. Here we report a rare case of surgically treated FAI, associated with an osseous protrusion on the acetabulum of a 30-year-old female. Plain computed tomography (CT) and reconstructive 3D-CT images clearly demonstrated an anterolateral bony protrusion. Hip arthroscopy showed no degeneration of the cartilage on either the femoral or acetabular side, but degeneration at the edge of labrum was observed in the region of the bony protrusion. The complete removal of the bony protrusion under hip arthroscopy was thus considered impracticable, and a small skin incision was therefore made anteriorly to approach the acetabulum. The Short-Form 36-Item Health Survey (SF-36) revealed improvement in all scores.</p>
Keywords femoroacetabular impingement bony protrusion Pincer type hip arthroscopy SF36
Amo Type Case Report
Published Date 2010-04
Publication Title Acta Medica Okayama
Volume volume64
Issue issue2
Publisher Okayama University Medical School
Start Page 149
End Page 154
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 20424671
Web of Science KeyUT 000276996900010
Title Alternative Japanese guidelines for the treatment of hip fractures in the elderly
FullText URL 122_253.pdf
Author Noda, Tomoyuki| Ozaki, Toshifumi|
Publication Title 岡山医学会雑誌
Published Date 2010-12-01
Volume volume122
Issue issue3
Start Page 253
End Page 257
ISSN 0030-1558
language 日本語
Copyright Holders Copyright (c) 2010 岡山医学会
File Version publisher
DOI 10.4044/joma.122.253
NAID 130004903185
Author Okada, Yoshiki| Abe, Nobuhiro| Hisamori, Noriyuki| Kaneeda, Toshiaki| Moriyama, Shigeaki| Ohmori, Hitoshi| Mizutani, Masayoshi| Yanai, Hiroyuki| Nakashima, Yoshio| Yokoyama, Yusuke| Ozaki, Toshifumi|
Published Date 2017-02
Publication Title Acta Medica Okayama
Volume volume71
Issue issue1
Content Type Journal Article
JaLCDOI 10.18926/AMO/54825
JaLCDOI 10.18926/AMO/58274
FullText URL 74_2_151.pdf
Author Yamamoto, Norio| Dan’ura, Tomoyuki| Noda, Tomoyuki| Ozaki, Toshifumi|
Abstract This is the second report of an atypical peri-implant femoral fracture occurring at the distal screw after intramedullary nail fixation of a pertrochanteric fracture. A 94-year-old Japanese female with a 5-year history of alendronate intake presented with prodromal pain in her right thigh after intramedullary nail fixation. Plain radiographs showed an incomplete noncomminuted transverse fracture at the distal screw, suggesting an atypical peri-implant femoral fracture. The pathogenesis of an atypical peri-implant femoral fracture could be a combined systemic bone metabolism disorder and repetitive overloading at the screw, similar to the pathogenesis of an atypical periprosthetic femoral fracture around stem implantation.
Keywords atypical femoral fracture insufficiency fracture bisphosphonate atypical peri-implant femoral fracture, atypical periprosthetic femoral fracture
Amo Type Case Report
Published Date 2020-04
Publication Title Acta Medica Okayama
Volume volume74
Issue issue2
Publisher Okayama University Medical School
Start Page 151
End Page 157
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders CopyrightⒸ 2020 by Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 32341590
Web of Science KeyUT 000528278500009
NAID 120006839453
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 Science KeyUT 000257130300006
JaLCDOI 10.18926/AMO/40007
FullText URL fulltext.pdf
Author Furumatsu, Takayuki| Ozaki, Toshifumi|
Abstract Epigenetics is an essential mechanism to control gene expression and fundamental cellular processes. DNA methylation in CpG-rich promoters correlates with gene silencing. Histone modification including histone acetylation and deacetylation determines the stability of the chromatin structure. Condensed chromatin (heterochromatin), which has a higher-order histone-DNA structure, prevents the access of transcriptional activators to their target genes. The fundamental unit of eukaryotic chromatin consists of 146 bp of DNA wrapped around a histone octamer. Posttranslational modifications of the histone tail and the chromatin remodeling complex disrupt histone-DNA contacts and induce nucleosome mobilization. Histone acetylation of specific lysine residues in the histone tail plays a crucial role in epigenetic regulation. Histone acetylation is a dynamic process regulated by the antagonistic actions of 2 families of enzymes - the histone acetyltransferases (HATs) and the histone deacetylases (HDACs). The balance between histone acetylation and deacetylation serves as a key epigenetic mechanism for transcription factor-dependent gene expression and the developmental process. We review emerging evidence that DNA methylation, histone acetylation modified by HAT and/or HDAC, and transcription factor-associated molecules contribute to a mechanism that can alter chromatin structure, gene expression, and cellular differentiation during chondrogenesis.
Keywords epigenetics DNA methylation histone acetylation and HAT histone deacetylation and HDAC chondrogenesis
Amo Type Review
Published Date 2010-06
Publication Title Acta Medica Okayama
Volume volume64
Issue issue3
Publisher Okayama University Medical School
Start Page 155
End Page 161
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
Copyright Holders Okayama University Medical School
File Version publisher
Refereed True
PubMed ID 20596126
Web of Science KeyUT 000279094300001
Author Furumatsu, Takayuki| Ozaki, Toshifumi| Asahara, Hiroshi|
Published Date 2010-08-02
Publication Title 岡山医学会雑誌
Volume volume122
Issue issue2
Content Type Journal Article
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
Author Miyake, Yoshiaki| Furumatsu, Takayuki| Kubota, Satoshi| Kawata, Kazumi| Ozaki, Toshifumi| Takigawa, Masaharu|
Published Date 2011-06-03
Publication Title Biochemical and Biophysical Research Communications
Volume volume409
Issue issue2
Content Type Journal Article
Author Saiga, Kenta| Furumatsu, Takayuki| Yoshida, Aki| Masuda, Shin| Takihira, Shota| Abe, Nobuhiro| Ozaki, Toshifumi|
Published Date 2010-11-12
Publication Title Biochemical and Biophysical Research Communications
Volume volume402
Issue issue2
Content Type Journal Article
Author Furumatsu, Takayuki| Hachioji, Motomi| Saiga, Kenta| Takata, Naoki| Yokoyama, Yusuke| Ozaki, Toshifumi|
Published Date 2010-01-01
Publication Title Biochemical and Biophysical Research Communications
Volume volume391
Issue issue1
Content Type Journal Article
Author Furumatsu, Takayuki| Shukunami, Chisa| Amemiya-Kudo, Michiyo| Shimano, Hitoshi| Ozaki, Toshifumi|
Published Date 2010-01
Publication Title The International Journal of Biochemistry & Cell Biology
Volume volume42
Issue issue1
Content Type Journal Article
Author Furumatsu, Takayuki| Ozaki, Toshifumi| Asahara, Hiroshi|
Published Date 2009-05
Publication Title The International Journal of Biochemistry & Cell Biology
Volume volume41
Issue issue5
Content Type Journal Article
Author Tetsunaga, Tomonori| Furumatsu, Takayuki| Abe, Nobuhiro| Nishida, Keiichiro| Naruse, Keiji| Ozaki, Toshifumi|
Published Date 2009-09-18
Publication Title Journal of Biomechanics
Volume volume42
Issue issue13
Content Type Journal Article
Author Furumatsu, Takayuki| Matsumoto, Emi| Kanazawa, Tomoko| Fujii, Masataka| Lu, Zhichao| Kajiki, Ryotaro| Ozaki, Toshifumi|
Published Date 2013-05-31
Publication Title Journal of Biomechanics
Volume volume46
Issue issue9
Content Type Journal Article
JaLCDOI 10.18926/AMO/49259
FullText URL 67_1_65.pdf
Author Sakata, Kenichiro| Furumatsu, Takayuki| Abe, Nobuhiro| Miyazawa, Shinichi| Sakoma, Yoshimasa| Ozaki, Toshifumi|
Abstract Bone marrow-stimulating techniques such as microfracture and subchondral drilling are valuable treatments for full-thickness cartilage defects. However, marrow stimulation-derived reparative tissues are not histologically well-documented in human osteoarthritis. We retrospectively investigated cartilage repairs after marrow stimulation for the treatment of large cartilage defects in osteoarthritic knees. Tissues were obtained from patients who underwent total knee arthroplasty (TKA) after arthroscopic marrow stimulation in medial compartmental osteoarthritis. Clinical findings and cartilage repair were assessed. Sections of medial femoral condyles were histologically investigated by safranin O staining and anti-type II collagen antibody. Marrow stimulation decreased the knee pain in the short term. However, varus leg alignment gradually progressed, and TKA conversions were required. The grade of cartilage repair was not improved. Marrow stimulations resulted in insufficient cartilage regeneration on medial femoral condyles. Safranin O-stained proteoglycans and type II collagen were observed in the deep zone of marrow-stimulated holes. This study demonstrated that marrow stimulation resulted in failed cartilage repair for the treatment of large cartilage defects in osteoarthritic knees. Our results suggest that arthroscopic marrow stimulation might not improve clinical symptoms for the long term in patients suffering large osteoarthritic cartilage defects.
Keywords bone marrow stimulation microfracture subchondral drilling osteoarthritis of the knee cartilage repair
Amo Type Case Report
Published Date 2013-02
Publication Title Acta Medica Okayama
Volume volume67
Issue issue1
Publisher Okayama University Medical School
Start Page 65
End Page 74
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 23439511
Web of Science KeyUT 000316829900009