n.

骨折

WordNet

interrupt, break, or destroy; "fracture the balance of power"
breaking of hard tissue such as bone; "it was a nasty fracture"; "the break seems to have been caused by a fall" (同)break
fracture a bone of; "I broke my foot while playing hockey" (同)break
become fractured; "The tibia fractured from the blow of the iron pipe"
break (a bone); "She broke her clavicle"
break into pieces; "The pothole fractured a bolt on the axle"
violate or abuse; "This writer really fractures the language"
the act of cracking something (同)crack, cracking

PrepTutorEJDIC

〈U〉(特に)骨を折ること;骨を折った状熊 / 〈C〉割れ(裂け)目,(鉱物の)破砕面 / 〈足・腕などを〉‘を'骨折する;…‘を'砕く / 骨折する;砕ける

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/11/07 11:14:17」(JST)

wiki en

[Wiki en表示]

For other uses, see Fracture (disambiguation).

A fracture is the separation of an object or material into two, or more, pieces under the action of stress.

The fracture of a solid almost always occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displacement develops in this case perpendicular to the surface of displacement, it is called a normal tensile crack or simply a crack; if a displacement develops tangentially to the surface of displacement, it is called a shear crack, slip band, or dislocation.^[1]

The word fracture is often applied to bones of living creatures (that is, a bone fracture), or to crystals or crystalline materials, such as gemstones or metal. Sometimes, in crystalline materials, individual crystals fracture without the body actually separating into two or more pieces. Depending on the substance which is fractured, a fracture reduces strength (most substances) or inhibits transmission of light (optical crystals).

A detailed understanding of how fracture occurs in materials may be assisted by the study of fracture mechanics.

A fracture is also the term used for a particular mask data preparation procedure within the realm of integrated circuit design that involves transposing complex polygons into simpler shapes such as trapezoids and rectangles.

Fracture strength[edit]

Stress vs. strain curve typical of aluminum
1. Ultimate tensile strength
2. Yield strength
3. Proportional limit stress
4. Fracture

5. Offset strain (typically 0.2%)

Fracture strength, also known as breaking strength, is the stress at which a specimen fails via fracture.^[2] This is usually determined for a given specimen by a tensile test, which charts the stress-strain curve (see image). The final recorded point is the fracture strength.

Ductile materials have a fracture strength lower than the ultimate tensile strength (UTS), whereas in brittle materials the fracture strength is equivalent to the UTS.^[2] If a ductile material reaches its ultimate tensile strength in a load-controlled situation,^{[Note 1]} it will continue to deform, with no additional load application, until it ruptures. However, if the loading is displacement-controlled,^{[Note 2]} the deformation of the material may relieve the load, preventing rupture.

If the stress-strain curve is plotted in terms of true stress and true strain the curve will always slope upwards and never reverse, as true stress is corrected for the decrease in cross-sectional area. The true stress on the material at the time of rupture is known as the breaking strength. This is the maximum stress on the true stress-strain curve, given by point 1 on curve B.

Types[edit]

Brittle fracture[edit]

Brittle fracture in glass.

Fracture of an aluminum crank arm. Bright: brittle fracture. Dark: fatigue fracture.

In brittle fracture, no apparent plastic deformation takes place before fracture. In brittle crystalline materials, fracture can occur by cleavage as the result of tensile stress acting normal to crystallographic planes with low bonding (cleavage planes). In amorphous solids, by contrast, the lack of a crystalline structure results in a conchoidal fracture, with cracks proceeding normal to the applied tension.

The theoretical strength of a crystalline material is (roughly)

where: -

is the Young's modulus of the material,

is the surface energy, and

is the equilibrium distance between atomic centers.

On the other hand, a crack introduces a stress concentration modeled by

(For sharp cracks)

where: -

is the loading stress,

is half the length of the crack, and

is the radius of curvature at the crack tip.

Putting these two equations together, we get

Looking closely, we can see that sharp cracks (small ) and large defects (large ) both lower the fracture strength of the material.

Recently, scientists have discovered supersonic fracture, the phenomenon of crack motion faster than the speed of sound in a material.^[3] This phenomenon was recently also verified by experiment of fracture in rubber-like materials.

Ductile fracture[edit]

Ductile failure of a specimen strained axially.

Schematic representation of the steps in ductile fracture (in pure tension).

In ductile fracture, extensive plastic deformation (necking) takes place before fracture. The terms rupture or ductile rupture describe the ultimate failure of tough ductile materials loaded in tension. Rather than cracking, the material "pulls apart," generally leaving a rough surface. In this case there is slow propagation and an absorption of a large amount energy before fracture.^{[citation needed]}

Many ductile metals, especially materials with high purity, can sustain very large deformation of 50–100% or more strain before fracture under favorable loading condition and environmental condition. The strain at which the fracture happens is controlled by the purity of the materials. At room temperature, pure iron can undergo deformation up to 100% strain before breaking, while cast iron or high-carbon steels can barely sustain 3% of strain.^{[citation needed]}

Because ductile rupture involves a high degree of plastic deformation, the fracture behavior of a propagating crack as modeled above changes fundamentally. Some of the energy from stress concentrations at the crack tips is dissipated by plastic deformation before the crack actually propagates.

The basic steps are: void formation, void coalescence (also known as crack formation), crack propagation, and failure, often resulting in a cup-and-cone shaped failure surface.

Crack separation modes[edit]

The three fracture modes.

There are three ways of applying a force to enable a crack to propagate:

Mode I crack – Opening mode (a tensile stress normal to the plane of the crack)
Mode II crack – Sliding mode (a shear stress acting parallel to the plane of the crack and perpendicular to the crack front)
Mode III crack – Tearing mode (a shear stress acting parallel to the plane of the crack and parallel to the crack front)

For more information, see fracture mechanics.

Crack initiation and propagation accompany fracture. The manner through which the crack propagates through the material gives great insight into the mode of fracture. In ductile materials (ductile fracture), the crack moves slowly and is accompanied by a large amount of plastic deformation. The crack will usually not extend unless an increased stress is applied. On the other hand, in dealing with brittle fracture, cracks spread very rapidly with little or no plastic deformation. The cracks that propagate in a brittle material will continue to grow and increase in magnitude once they are initiated. Another important mannerism of crack propagation is the way in which the advancing crack travels through the material. A crack that passes through the grains within the material is undergoing transgranular fracture. However, a crack that propagates along the grain boundaries is termed an intergranular fracture.

Notes[edit]

^ A simple load-controlled tensile situation would be to support a specimen from above, and hang a weight from the bottom end. The load on the specimen is then independent of its deformation.
^ A simple displacement-controlled tensile situation would be to attach a very stiff jack to the ends of a specimen. As the jack extends, it controls the displacement of the specimen; the load on the specimen is dependent on the deformation.

References[edit]

^ Cherepanov, G.P., Mechanics of Brittle Fracture
^ ^a ^b Degarmo, E. Paul; Black, J T.; Kohser, Ronald A. (2003), Materials and Processes in Manufacturing (9th ed.), Wiley, p. 32, ISBN 0-471-65653-4.
^ C. H. Chen, H. P. Zhang, J. Niemczura, K. Ravi-Chandar and M. Marder (November 2011). "Scaling of crack propagation in rubber sheets". Europhysics Letters 96 (3): 36009. Bibcode:2011EL.....9636009C. doi:10.1209/0295-5075/96/36009.

External links[edit]

Web postings at http://www.jwave.vt.edu/crcd/farkas/lectures/Fract1/tsld006.htm
Virtual museum of failed products at http://materials.open.ac.uk/mem/index.html
Fracture and Reconstruction of a Clay Bowl
Ductile fracture
Modes of Fracture from Virginia Tech Materials Science and Engineering

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 骨折のマネージメントの一般原則：骨治癒および骨折について general principles of fracture management bone healing and fracture description
2. 指、手、および手首の骨折の概要 overview of finger hand and wrist fractures
3. 骨折のマネージメントの一般原則：小児における骨折のパターンおよび種類 general principles of fracture management fracture patterns and description in children
4. ストレス骨折の概要 overview of stress fractures
5. 成人における足関節骨折の概要 overview of ankle fractures in adults

English Journal

Twenty-One-Year Follow-Up of Supination-External Rotation Type II-IV (Orthopaedic Trauma Association Type B) Ankle Fractures: A Retrospective Cohort study.

Donken CC, Verhofstad MH, Edwards MJ, van Laarhoven CJ.SourceFrom the *Department of Surgery, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; and the †Department of Surgery, St Elisabeth Hospital, Tilburg, The Netherlands.
Journal of orthopaedic trauma.J Orthop Trauma.2012 Dec 21. [Epub ahead of print]
OBJECTIVE: To evaluate long-term results after protocoled treatment of supination-external rotation (SER) Type II-IV ankle injuries.DESIGN: Retrospective cohort study.SETTING: Level I trauma center.PATIENTS: Two hundred seventy-six adult patients with an SER Type II-IV ankle fracture between January
PMID 22198654

Relationship between types of head injury and age of pedestrian.

Richards D, Carroll J.SourceTRL (Transport Research Laboratory), Crowthorne House, Nine Mile Ride, Wokingham, Berkshire RG40 3GA, United Kingdom.
Accident; analysis and prevention.Accid Anal Prev.2012 Jul;47:16-23. Epub 2012 Feb 2.
This paper explores the relationship between age and the different types of head injury received by pedestrians in traffic accidents with cars. The analysis is based on information collected by hospitals in England, and is supported by in-depth case examples. The principle result is that the risk of
PMID 22405234

Corticosteroid-induced osteoporosis: an update for dermatologists.

Clarke BL.SourceMayo Clinic School of Medicine, Rochester, MN, USA.
American journal of clinical dermatology.Am J Clin Dermatol.2012 Jun 1;13(3):167-90. doi: 10.2165/11594250-000000000-00000.
Long-term corticosteroid treatment is the most common secondary cause of bone loss. Patients treated with long-term corticosteroid therapy may develop osteopenia or osteoporosis, and many have fractures. It is difficult to predict which corticosteroid-treated patients will develop significant skelet
PMID 22393910

Skeletal metastasis in renal cell carcinoma: Current and future management options.

Wood SL, Brown JE.SourceCancer Research UK Clinical Centre at Leeds, University of Leeds, St. James's Hospital, Leeds, UK.
Cancer treatment reviews.Cancer Treat Rev.2012 Jun;38(4):284-91. Epub 2011 Jul 29.
Metastasis to the skeleton is common in advanced renal cancer and leads to debilitating skeletal complications including severe pain, increased fracture rate and spinal cord compression. The incidence of renal cell carcinoma is increasing by around 2% per year and recent advances in targeted anti-an
PMID 21802857

Japanese Journal

Influence of Microstructure on Fatigue Fracture Characteristics of Al2O3

Kido Mitsuo,Katayama Gounozyo,Inoda Nana,Tsuchibushi Yasuyuki
広島工業大学研究紀要 33, 67-74, 36192-00-00
… Fatigue fracture characteristics under static and cyclic loading were investigated for three kinds of Al2O3, with microstructures controlled by sintering additives (MgO, SiO2+CaO) and particle size. … In addition, surface analysis by EDX on fatigue fracture surfaces in Material SC showed that Si and Ca, the components of the sintering additives, were decreased markedly at SCG sites under cyclic loading in water. …
NAID 120005403235

屋久島沿岸域の岩盤露頭における単一割れ目内の充填物の年代値とその変動要因の検討

松下智昭,長田昌彦,高橋学 [他]
応用地質 = Journal of the Japan Society of Engineering Geology 56(1), 2-14, 2015-04
NAID 40020439806

EBM講座(第46回)海外の治験データを中心としたカテプシンKに関する最新情報

田井宣之,井上大輔
骨粗鬆症治療 = Journal of osteoporotic medicine 14(1), 64-68, 2015-04
NAID 40020438094

第64回(平成26年度)全国工作責任者大会特別講演から構造用鋼溶接継手の強度と破壊評価

南二三吉
ボイラ研究 (390), 19-25, 2015-04
NAID 40020433172

Related Pictures

$full size version of Pseudo-Jones fracture$ $full size version of Monteggia fracture$ $full size version of Galeazzi fracture$ $full size version of Incomplete fracture$ $View full size version of Patella fracture$

★リンクテーブル★

リンク元	「100Cases 16」「骨折」「吹き抜け骨折」「broken bone」「破砕」
拡張検索	「bone fracture」

「100Cases 16」

　　[★]

☆case16　膝の痛み

■glossary

indigestion 消化障害、消化不良

■症例

80歳　男性

主訴：左膝の痛みと腫脹

現病歴：左膝の痛みを2日前から認めた。膝は発熱・腫脹しており、動かすと疼痛を生じる。時々胸焼けと消化不良が見られる。6ヶ月前のhealth checkで、高血圧(172/102mmHg)と血中クレアチニンが高い(正常高値)こと以外は正常といわれた。その4週間数回血圧を測定したが、高値が継続したため、2.5mg bendrofluamethizide(UK)/ベンドロフルメチアジド bendroflumethiazide(US)で治療を開始した。最近の血圧は138/84 mmHgであった。

喫煙歴：なし。

飲酒歴：一週間に平均4unit。

既往歴：股関節に中程度(mild)の変形性関節症

家族歴：特記なし

服薬歴：アセトアミノフェン(股関節の疼痛に対して)

身体所見 examination

　血圧 142/86mmHg。体温37.5℃。脈拍88/分。grade 2 hypertensive retinopathy(高血圧症性網膜症)。心血管系、呼吸器系に検査場異常なし。手にDIPにヘバーデン結節なし。

　左膝が発熱し腫脹している。関節内に液、patellar tap陽性。90℃以上膝関節を屈曲させると痛みを生じる。右の膝関節は正常に見える。

検査　 investigation

　生化学：白血球増多、ESR 上昇、尿素高値、グルコース高値

　単純X線：関節間隙やや狭小。それ以外に異常は認めない。

■problem list

　#1 左膝の痛み

　#2 胸焼け

　#3 消化不良

　#4 高血圧

　#5 クレアチニン正常高値

　#6 股関節の変形性リウマチ

　#7 高血圧性網膜症

■考え方

　・関節痛の鑑別診断を考える。

　・VINDICATEで考えてみてもよいでしょう。

　・関節痛の頻度としては　外傷＞慢性疾患(OAなど)＞膠原病＞脊椎疾患＞悪性腫瘍

■関節痛の鑑別疾患

DIF 282

V Vascular 血友病 hemophilia, 壊血病 scurvy, 無菌性骨壊死 aseptic bone necrosis (Osgood-Schlatter diseaseとか)

I Inflammatory 淋疾 gonorrhea, ライム病 lyme disease, 黄色ブドウ球菌 Staphylococcus, 連鎖球菌 Streptococcus, 結核 tuberculosis, 梅毒 syphilis, 風疹 rubella, 単純ヘルペス herpes simplex, HIV human immunodeficiency virus, サイトメガロウイルス cytomegalovirus

N Neoplastic disorders 骨原性肉腫 osteogenic sarcoma, 巨細胞腫 giant cell tumors

D Degenerative disorders degenerative joint disease or 変形性関節症 osteoarthritis

I Intoxication 痛風 gout (uric acid), 偽痛風 pseudogout (calcium pyrophosphate), ループス症候群 lupus syndrome of hydralazine (Apresoline) and procainamide, gout syndrome of diuretics

C Congenital and acquired malformations bring to mind the joint deformities of tabes dorsalis and syringomyelia and congenital dislocation of the hip. Alkaptonuria is also considered here.

A Autoimmune indicates (多い)関節リウマチ RA (可能性)血清病 serum sickness, 全身性エリテマトーデス lupus erythematosus, リウマチ熱 rheumatic fever, ライター症候群 Reiter syndrome, 潰瘍性大腸炎 ulcerative colitis, クローン病=限局性回腸炎 regional ileitis, 乾癬性関節炎 psoriatic arthritis (老人であり得る)リウマチ性多発筋痛症 polymyalgia rheumatica

T Trauma 外傷性滑膜炎 traumatic synovitis, tear or rupture of the collateral or cruciate ligaments, 亜脱臼 subluxation or laceration of the meniscus (semilunar cartilage), 脱臼 dislocation of the joint or patella, a 捻挫　 sprain of the joint, and fracture of the bones of the joint.

E Endcrine 先端肥大症 acromegaly, 閉経 menopause, 糖尿病 diabetes mellitus

■答え

　骨格筋系-関節炎-単関節炎-急性単関節炎

　痛風　尿酸　→　発熱、ESR↑、白血球↑

　偽痛風　ピロリン酸カルシウム

　高齢女性でチアジド系利尿薬の使用により痛風が誘発されやすい。特に腎機能低下、糖尿病の人はこのリスクが高まる。

■(BSTからの知識「)循環器領域での利尿薬

・心不全の治療において、循環血漿量を減らし、心臓の前負荷を軽減する。

・利尿薬は高尿酸血症を起こす。(けど、心不全の治療において高尿酸血症になったからといって痛風を発症している患者はみたことない)

・電解質異常を起こしやすいので、血液生化学の検査でモニタして注意する。たとえば低Kで不整脈のリスクが高まる。

・チアジド系の利尿薬は血糖を上げるし、尿酸を上げる

・長期の使用で腎機能を低下させる

■initial plan

　Dx 1. 関節液の吸引：関節液の一般検査、生化学検査、培養検査、

　　　　・白血球が増加していれば急性炎症性であることを示す。

　　　　・偏光顕微鏡で関節液を検鏡する。

　　　　　・尿酸の結晶：針状結晶。negatively birefringent

　　　　　・ピロリン酸カルシウムの結晶：positively birefringent

　Tx 1. 関節液の吸引：炎症が軽度改善

　　 2. NSAIDによる疼痛管理

　　 3. PPI：NSAID 潰瘍を予防するため

　　 4. ACE inhibitorの導入

「骨折」

　　[★]

英: fracture
関

高齢者における骨折の好発部位

参考1

多い

上腕骨頚部：転倒して手を伸ばしてついた、直接方外側を打った場合に外科頚骨折しやすい。特に高齢者、特に女性に多い。
橈骨遠位部：コーレス骨折(Colles骨折)は10歳前後の小児と骨粗鬆症を有する老人に多い。
椎骨(椎体圧迫骨折)：骨粗鬆症を生じている女性に多い。
大腿骨頚部

やや多い

肋骨
上腕骨遠位部
坐骨？
大腿骨遠位部
脛骨近位部
脛骨位部

小児の骨折

→小児骨折

骨折による骨癒合しにくい部位

血流が乏しいことによる

大腿骨頚部内側骨折、手根骨舟状骨骨折、脛骨中下1/3骨折、距骨骨折

骨折による出血量

SOR.631

開放骨折の場合には2倍の出血量が予想される。

骨盤骨折	1000-5000ml
大腿骨骨折	500-1000ml
脛骨骨折	500ml
上腕骨骨折	350ml

診察

1. 皮下骨折/開放骨折
2. 血管損傷の有無
3. 末梢神経損傷の有無
4. 軟部組織の損傷
5. 受傷部位周辺臓器の損傷
6. 受傷後の時間経過

参考

1. 高齢者の転倒障害

http://www.biomech.mech.nagoya-u.ac.jp/iplweb/impact_bio/pdf/1st/Harada.pdf

「吹き抜け骨折」

　　[★]

英: blow out fracture, blow-out fracture, blowout fracture
関: 眼窩吹き抜け骨折、眼窩底吹き抜け骨折

[show details]

うち出し骨折 : 35 件
眼窩底破裂骨折 : 84 件
強打骨折 : 約 3,000 件
吹抜け骨折 : 約 912 件
吹き抜け骨折 : 約 10,700 件
ブロウアウト眼窩骨折 : 30 件

うち出し骨折 fracture : 16 件
眼窩底破裂骨折 fracture : 35 件
強打骨折 fracture : 9 件
吹抜け骨折 fracture : 45 件
吹き抜け骨折 fracture : 約 942 件
ブロウアウト眼窩骨折 fracture : 23 件