中华创伤骨科杂志
中華創傷骨科雜誌
중화창상골과잡지
CHINESE JOURNAL OF ORTHOPAEDIC TRAUMA
2010年
1期
61-65
,共5页
郑凯%郭征%郝玉琳%李述军
鄭凱%郭徵%郝玉琳%李述軍
정개%곽정%학옥림%리술군
股骨骨折%外固定器%生物力学%骨折,应力性%弹性模量
股骨骨摺%外固定器%生物力學%骨摺,應力性%彈性模量
고골골절%외고정기%생물역학%골절,응력성%탄성모량
Femoral fractures%External fixator%Biomechanics%Fractures,stress%Modulus of elasticity
目的 通过在模拟股骨上对不同弹性模量的外固定系统进行生物力学测试,探讨不同弹性模量外固定系统对股骨干骨折应力及其分布的影响.方法 选择8套与人体股骨力学性质类似的玻璃钢制成股骨干骨折模型,在模型上分别安装Ti-24Nb-4Zr-7.9Sn(低弹性模量组,弹性模量为33 Gpa,4套)和Ti-6Al-4V(高弹性模量组,弹性模量为110 Gpa,4套)钛合金半针,连接套夹和碳纤维外固定棒,在骨折断面,外固定半针以及钉道周围粘贴电阻应变计,分析局部应力,测量不同弹性模量外固定系统在同样载倚条件下骨折断面及钉道周围应力的大小和分布.结果 在实验载倚条件下,随着载荷和力矩的增大,高弹性模量组与低弹性模量组骨折断端和钉道周围应力有不同程度增大.当侧压载荷为90 N时,两组的侧压应变值分别为(6.5±3.5)×10~(-6)、(43.5±22.7)×10~(-6);当侧压载荷为300 N时,应变值为(16.5±0.7)×10~(-6)、(140.5±9.5)×10~(-6).当弯曲载荷为1.6 N·m时,两组的应变值分别为(0.3±0.5)×10~(-6)、(47.1±31.5)×10~(-6);当弯曲载荷为11.0 N·m时,应变值分别为(359.7±39.9)×10~(-6)、(453.5±29.0)×10~(-6).当侧压载荷≥90 N或弯曲载倚介于1.6～8.8 N·m时,两组之间骨折断端应力应变值差异有统计学意义(P<0.05).在3种力学作用下,与高弹性模量组相比,低弹性模量组钉道局部应力分布更均匀,应力相对集中的针道局部应力变小.结论 低弹性模量外固定系统有利于应力传导,更符合生物力学的要求,从而可能有效避免应力遮挡效应,促进骨折愈合.
目的 通過在模擬股骨上對不同彈性模量的外固定繫統進行生物力學測試,探討不同彈性模量外固定繫統對股骨榦骨摺應力及其分佈的影響.方法 選擇8套與人體股骨力學性質類似的玻璃鋼製成股骨榦骨摺模型,在模型上分彆安裝Ti-24Nb-4Zr-7.9Sn(低彈性模量組,彈性模量為33 Gpa,4套)和Ti-6Al-4V(高彈性模量組,彈性模量為110 Gpa,4套)鈦閤金半針,連接套夾和碳纖維外固定棒,在骨摺斷麵,外固定半針以及釘道週圍粘貼電阻應變計,分析跼部應力,測量不同彈性模量外固定繫統在同樣載倚條件下骨摺斷麵及釘道週圍應力的大小和分佈.結果 在實驗載倚條件下,隨著載荷和力矩的增大,高彈性模量組與低彈性模量組骨摺斷耑和釘道週圍應力有不同程度增大.噹側壓載荷為90 N時,兩組的側壓應變值分彆為(6.5±3.5)×10~(-6)、(43.5±22.7)×10~(-6);噹側壓載荷為300 N時,應變值為(16.5±0.7)×10~(-6)、(140.5±9.5)×10~(-6).噹彎麯載荷為1.6 N·m時,兩組的應變值分彆為(0.3±0.5)×10~(-6)、(47.1±31.5)×10~(-6);噹彎麯載荷為11.0 N·m時,應變值分彆為(359.7±39.9)×10~(-6)、(453.5±29.0)×10~(-6).噹側壓載荷≥90 N或彎麯載倚介于1.6～8.8 N·m時,兩組之間骨摺斷耑應力應變值差異有統計學意義(P<0.05).在3種力學作用下,與高彈性模量組相比,低彈性模量組釘道跼部應力分佈更均勻,應力相對集中的針道跼部應力變小.結論 低彈性模量外固定繫統有利于應力傳導,更符閤生物力學的要求,從而可能有效避免應力遮擋效應,促進骨摺愈閤.
목적 통과재모의고골상대불동탄성모량적외고정계통진행생물역학측시,탐토불동탄성모량외고정계통대고골간골절응력급기분포적영향.방법 선택8투여인체고골역학성질유사적파리강제성고골간골절모형,재모형상분별안장Ti-24Nb-4Zr-7.9Sn(저탄성모량조,탄성모량위33 Gpa,4투)화Ti-6Al-4V(고탄성모량조,탄성모량위110 Gpa,4투)태합금반침,련접투협화탄섬유외고정봉,재골절단면,외고정반침이급정도주위점첩전조응변계,분석국부응력,측량불동탄성모량외고정계통재동양재의조건하골절단면급정도주위응력적대소화분포.결과 재실험재의조건하,수착재하화력구적증대,고탄성모량조여저탄성모량조골절단단화정도주위응력유불동정도증대.당측압재하위90 N시,량조적측압응변치분별위(6.5±3.5)×10~(-6)、(43.5±22.7)×10~(-6);당측압재하위300 N시,응변치위(16.5±0.7)×10~(-6)、(140.5±9.5)×10~(-6).당만곡재하위1.6 N·m시,량조적응변치분별위(0.3±0.5)×10~(-6)、(47.1±31.5)×10~(-6);당만곡재하위11.0 N·m시,응변치분별위(359.7±39.9)×10~(-6)、(453.5±29.0)×10~(-6).당측압재하≥90 N혹만곡재의개우1.6～8.8 N·m시,량조지간골절단단응력응변치차이유통계학의의(P<0.05).재3충역학작용하,여고탄성모량조상비,저탄성모량조정도국부응력분포경균균,응력상대집중적침도국부응력변소.결론 저탄성모량외고정계통유리우응력전도,경부합생물역학적요구,종이가능유효피면응력차당효응,촉진골절유합.
Objective To explore the effects of external fixation system with various moduli of e-lasticity on the stress and its distribution at a femoral shaft fracture. Methods Glass fiber reinforced plastic (GFRP) which resembles human femur in mechanics was used to create 8 models of femoral shaft fracture. Four models were of low elastic modulus group in which the halfpins of the external fixation system were made of titanium alloy Ti-24Nb-4Zr-7. 9Sn (E = 33 GPa) while the uther 4 were of high elastic modulus group in which the external fixation system were made of titanium alloy Ti-6A1-4V (E=110 GPa) . Strain gages were mounted near the fracture plane, halfpin and pin track to detect the stresses and their distributions under the same load in the 2 external fixation systems of different moduli of elasticity. Results The stresses at the fracture end and around the pin track increased with an increase in the load and moment. When the lateral pressure load was not less than 90 N or the bending load ranged from 1.6 N·m to 8.8 N·m, the differences in the stress at the fracture end were significant between the 2 groups (P<0.05). In 3 kinds of operating modes, the low elastic modulus group showed more symmetrical distribution and less stress concentration around the pin track. Conclusion Since external fixation system of low elasticity modulus may be better in stress transmission and distribution, it can reduce the effect of stress-shielding and accelerate bone-healing.
