山子 剛 (ヤマコ ゴウ)

YAMAKO Go

写真a

職名

准教授

研究分野・キーワード

生体機械工学

取得学位 【 表示 / 非表示

  • 新潟大学 -  博士(工学)

専門分野(科研費分類) 【 表示 / 非表示

  • 生体医工学・生体材料学

  • 機械材料・材料力学

 

論文 【 表示 / 非表示

  • One-dimensional standing and sitting interface based on relative distances

    Geunho Lee, Yuki Fujio, Go Yamako, Hiroki Tamura, Etsuo Chosa

    Proc. 7th IIAE International Conference on Industrial Application Engineering     146 - 149   2019年03月  [査読有り]

    共著

  • Effects of a valgus unloader brace in the medial meniscectomized knee joint: a biomechanical study

    Shriram D., Yamako G., Chosa E., Lee Y., Subburaj K.

    Journal of orthopaedic surgery and research   14 ( 1 )   2019年02月  [査読有り]

    共著

     概要を見る

    BACKGROUND: Patients undergoing total or partial arthroscopic meniscectomy for treating traumatic meniscal tears are at greater risk of developing knee osteoarthritis (OA) due to increased mechanical load. The purpose of this study was to evaluate the effects of a valgus unloader brace in the medial meniscectomized knee joint during the gait cycle. METHODS: A three-dimensional finite element model of the knee joint was developed using the substructures segmented from magnetic resonance images. Experimentally measured forces and moments for one complete gait cycle, without brace and with brace at three different alignment angles (0°, 4°, and 8°), were applied to the finite element model, and the changes in the tibiofemoral contact mechanics were estimated. RESULTS: The brace in 0°/4°/8° valgus alignment modes reduced the total contact force in the medial compartment by 16%/46%/82% at opposite toe off and 18%/17%/29% at opposite initial contact events, while it increased the total contact force in the lateral compartment by 31%/81%/110% at opposite toe off and 30%/38%/45% at opposite initial contact events, respectively, when compared to the unbraced meniscectomized knee. CONCLUSIONS: Increasing the valgus alignment from 0° to 4° and 8° resulted in a greater reduction of contact conditions (total contact force, total contact area, peak contact pressure) in the medial compartment and vice versa in the lateral compartment. This decrease in contact conditions in the medial compartment infers enhanced knee joint function due to a valgus unloader brace, which translates to increased knee-related confidence. Results suggest choosing a higher valgus alignment angle could potentially increase the risk for the onset of osteoarthritis in the lateral compartment, and this computational model could be used in validating the effectiveness of braces on joint health.

    DOI

  • Identification of key events in baseball hitting using inertial measurement units

    Punchihewa N., Yamako G., Fukao Y., Chosa E.

    Journal of Biomechanics     2019年  [査読有り]

    共著

     概要を見る

    © 2019 Quantification of baseball hitting mechanics under game conditions help players to become successful batters and prevent injuries. Inertial measurement units (IMUs) can measure motion without any spatial restriction and are thus becoming a popular tool to investigate sports biomechanics. Biomechanical analysis of hitting requires the accurate detection of key events including “foot-off” while leaning back (F Off ), “foot-on” during forward swing (F On ), and ball impact. Ten male university baseball players hit a ball suspended on a T pole five times in kick-hitting and glide-hitting styles. Three IMUs were attached on mid-pelvis and on each hand to record acceleration and orientation data. The key events identified by the three IMUs were compared with those retrieved by an optical motion capture system with force platforms. The timings of the local peak acceleration of the pelvis in the direction of the pitcher that were recorded by the IMU closely matched those of F Off and F On events detected by the ground reaction force. Root mean square error (RMSE) between each measurement for the F Off and F On events were 0.024 and 0.031 s, respectively. The timing of the

    DOI PubMed

  • Acetabular reinforcement ring with additional hook improves stability in three-dimensional finite element analyses of dysplastic hip arthroplasty

    Totoribe K., Chosa E., Yamako G., Zhao X., Ouchi K., Hamada H., Deng G.

    Journal of Orthopaedic Surgery and Research   13 ( 1 ) 313   2018年12月  [査読有り]

    共著

     概要を見る

    © 2018 The Author(s). Background: The stability of acetabulum reconstructions using reinforcement rings and hooks is important for successful replacement surgery. The objective of this study was to biomechanically determine the effects of the hook on stress and the related micromotions of the acetabular reinforcement ring during the immediate postoperative period. Methods: Acetabular reinforcement ring models were developed using a nonlinear, three-dimensional, finite element method. Using a pre-prepared template, we constructed without-hook and bone graft models of varying volumes and material properties. Results: The stress on the inferior margin of the acetabulum was higher in the with-hook model than in the without-hook model, especially with increased bone graft volumes, and the stiffness of the bone graft material was decreased. Relative micromotions in the without-hook model were higher than in the with-hook models. The highest relative micromotion was observed in the model with increased bone graft volume and lower stiffness of bone graft material. Conclusions: In biomechanical analyses, the hook effectively dispersed stress and improved the initial fixation strength of the acetabular reinforcement ring.

    DOI PubMed

  • Biomechanical analysis of supra-acetabular insufficiency fracture using finite element analysis

    Tanaka H., Yamako G., Kurishima H., Yamashita S., Mori Y., Chiba D., Chosa E., Itoi E.

    Journal of Orthopaedic Science   23 ( 5 ) 825 - 833   2018年09月  [査読有り]

    共著

     概要を見る

    © 2018 Background: Supra-acetabular insufficiency fractures (SAIFs) occur in the upper acetabulum and are rare compared with insufficiency sacral, femoral head, or ischial fractures. However, SAIFs are known to occur in low grade trauma, and the underlying mechanism is still remained unclear. Methods: We performed biomechanical analysis using finite element analysis to clarify the mechanisms underlying the development of SAIFs. Patient-specific models and bone mineral density (BMD) were derived from pelvic computed tomography data from two patients with SAIF (unaffected side) and two healthy young adults. The bone was assumed to be an isotropic, linearly elastic body. We assigned Young's modulus of each element to the pelvis based on the BMD, and reported the relationships for BMD–modulus. Clinically relevant loading conditions—walking and climbing stairs—were applied to the models. We compared the region of failure risk in each acetabulum using a maximum principal strain criterion. Results: The average supra-acetabular BMD was less than that of the hemi-pelvis and femoral head, but was higher than that of the femoral neck and greater trochanter. Greater minimum principal strain was concentrated in the supra-acetabular portion in both the SAIF and healthy models. In the SAIF models, the higher region of the failure risk matched the fracture site on the acetabulum. Conclusions: Relative fragility causes compressive strain to concentrate in the upper acetabulum when walking and climbing stairs. When presented with a patient complaining of hip pain without apparent trauma or abnormal X-ray findings, physicians should consider the possibility of SAIF and perform magnetic resonance imaging for the diagnosis of SAIF.

    DOI

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著書 【 表示 / 非表示

  • 関節外科(特集 運動器を扱うメディカルスタッフのためのバイオメカニクス必携)

    企画・編集:帖佐 悦男 (担当: 共著 )

    メジカルビュー社  2016年11月

  • 関節外科(特集 運動器を扱うメディカルスタッフのためのバイオメカニクス必携)

    企画・編集:帖佐 悦男 (担当: その他 )

    メジカルビュー社  2016年11月

  • 未来型人工関節を目指して -その歴史から将来展望まで―

    吉川秀樹, 他 (担当: 共著 , 担当範囲: pp.181-186 )

    日本医学館  2013年07月

  • 未来型人工関節を目指して -その歴史から将来展望まで―

    吉川秀樹, 他 (担当: その他 , 担当範囲: pp.181-186 )

    日本医学館  2013年07月

  • 整形・災害外科 (特集 骨・関節のバイオメカニクス –最近の進歩)

    企画:黒坂昌弘 (担当: 共著 , 担当範囲: pp.1365-1374 )

    金原出版  2012年10月 ISBN: 0387-4095

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総説・解説記事 【 表示 / 非表示

工業所有権 【 表示 / 非表示

  • 運動器評価システム及び運動器評価方法

    特願 特願2015-185872  特許 特許第6281876号

    山子 剛,帖佐 悦男

  • 立ち上がり能力測定用の椅子及び立ち上がり能力評価システム

    特願 特願2014-240243  特許 6493781

    鄧 鋼,帖佐 悦男,山子 剛

学術関係受賞 【 表示 / 非表示

  • Best Paper Award

    2019年03月28日   The 7th IIAE International Conference on Industrial Application Engineering  

    受賞者:  Geunho Lee, Yuki Fujio, Go Yamako, Hiroki Tamura, Etsuo Chosa

  • Outstanding Contribution in Reviewing(Clinical Biomechanics)

    2017年04月   ELSEVIER  

    受賞者:  Go Yamako

  • Outstanding Contribution in Reviewing(Medical Engineering & Physics)

    2015年01月   Elsevier  

    受賞者:  Go Yamako

科研費(文科省・学振)獲得実績 【 表示 / 非表示

  • 人工股関節全置換術後の生体力学的な未来予測

    基盤研究(C)

    研究期間:  2017年04月  -  2020年03月  代表者:  山子 剛

  • 術後の骨量減少が生じない傾斜低弾性人工股関節ステムの最適化研究(国際共同研究強化)

    国際共同研究加速基金(国際共同研究強化)

    研究期間:  2016年04月  -  2018年03月  代表者:  山子 剛

  • 術後の骨量減少が生じない傾斜低弾性人工股関節ステムの最適化研究

    若手研究(B)

    研究期間:  2014年04月  -  2016年03月  代表者:  山子 剛

  • 皮質骨の微細孔構造及び基質の石灰化が骨力学特性に及ぼす影響

    若手研究(B)

    研究期間:  2008年04月  -  2010年03月  代表者:  山子 剛

その他競争的資金獲得実績 【 表示 / 非表示

  • フォースプレートを用いた『ロコモ』モニタリングシステムの製品化

    提供機関:  国立研究開発法人 科学技術振興機構  JST マッチングプランナープログラム「探索試験」

    研究期間: 2015年04月  -  2017年03月  代表者:  山子 剛

  • 機械的強度と弾性率を部位毎に最適化させた新素材活用による新たな人工 股関節ステムの開発と事業化

    提供機関:  国立研究開発法人日本医療研究開発機構  AMED 医工連携事業化推進事業

    研究期間: 2014年04月  -  2017年03月 

  • マッチング研削システムによるMetal on metal型人工股関節摺動面の高精度クリアランス制御

    提供機関:  その他省庁等  中小企業庁 戦略的基盤技術高度化事業(サポイン)

    研究期間: 2013年04月  -  2014年03月 

  • Micro-CT装置を利用した骨石灰化度測定システムの開発

    提供機関:  国立研究開発法人 科学技術振興機構  JST シーズ発掘試験(A)

    研究期間: 2008年04月  -  2009年03月  代表者:  山子 剛

  • 大腿骨髄外アライメントガイドの研究開発

    提供機関:  国立研究開発法人 科学技術振興機構  JST 研究成果実用化検討(FS)課題

    研究期間: 2007年04月  -  2008年03月  代表者:  山子 剛

研究発表 【 表示 / 非表示

  • Evaluation of Pressure Distribution on Patellar-Tendon-Bearing Sockets during Walking and Stair Ascent and Descent in Two Subjects

    Koji Totoribe, Etsuo Chosa, Go Yamako, Xin Zhao, Hiroaki Hamada, Koki Ouchi, Gang Deng

    ORS 2019 Annual Meeting  (Austin, TX)  2019年02月  -  2019年02月   

  • Hip Joint Reaction Force during the Gait on the Healthy and Diseased side of Patients with Unilateral Hip Osteoarthritis

    Koki Ouchi, Deng Gang, Go Yamako, Koji Totoribe, Etsuo Chosa

    ORS 2019 Annual Meeting  (Austin, TX)  2019年02月  -  2019年02月   

  • 変形性股関節症患者を対象とした三次元動作解析時における股関節中心位置に関する検討

    露木天哉,鄧鋼,大内宏輝,山子剛,鳥取部光司, 帖佐悦男

    第45回日本臨床バイオメカニクス学会  (秋田)  2018年11月  -  2018年11月   

  • 片側変形性股関節症患者を対象とした歩行時における健側と患側の股関節反力の検討

    大内宏輝,鄧鋼,山子剛,鳥取部光司, 帖佐悦男

    第45回日本臨床バイオメカニクス学会  (秋田)  2018年11月  -  2018年11月   

  • 人工股関節置換術におけるロングステムの有限要素解析:スクリュー本数の影響

    鳥取部光司, 帖佐悦男,山子剛,大内宏輝,鄧鋼

    第45回日本臨床バイオメカニクス学会  (秋田)  2018年11月  -  2018年11月   

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