摘要
背景:肘关节"恐怖三联征"是严重复杂的骨折脱位损伤。能否通过修复内侧副韧带结构替代冠状突骨块的固定来重建肘关节的稳定性值得探讨研究。目的:通过建立肘关节"恐怖三联征"的有限元模型,在肘关节外侧柱稳定性重建的基础上,比较尺骨冠状突骨折固定和内侧副韧带修补两种模式下,肘关节不同屈曲角度的力学值,评价两种手术方法对肘关节稳定性的影响。方法:利用肘关节CT、MRI图片的相关数据,计算机生成命令流文件,建立肘关节实体模型,进行网格划分,去除1/3冠状突,去除桡骨小头及内外侧副韧带即为恐怖三联征模型。模拟内侧副韧带断裂后是否进行修复,冠状突骨块是否固定两种情况,并且对其分别施加纵向载荷,分析各种工况条件下肘关节关节面的应力分布,比较肘关节的稳定性。结果与结论:①肘关节伸直位0°时正常肘关节关节面的最大应力为0.78 MPa。将1/3冠状突骨折模型骨折做固定,内侧副韧带不修补,该模型关节面的最大应力为0.84MPa,而冠状突骨折不做固定,仅修补内侧副韧带的肘关节模型关节面的最大应力也是0.84MPa;②肘关节屈曲30°时正常肘关节模型关节面的最大应力为2.02 MPa,将1/3冠状突骨折模型骨折做固定,内侧副韧带不修补,该模型关节面的最大应力为2.02 MPa,而冠状突骨折不做固定,修补内侧副韧带的肘关节模型关节面的最大应力为2.07 MPa;③肘关节伸直位0°时正常肘关节关节面的最大位移为0.14 mm,将1/3冠状突骨折模型骨折做固定,内侧副韧带不修补,该模型关节面的最大位移为0.15mm,而冠状突骨折不做固定,修补内侧副韧带的肘关节模型关节面的最大位移为0.16 mm;④肘关节屈曲30°时正常肘关节模型关节面的最大位移为0.52 mm,将1/3冠状突骨折做固定,内侧副韧带不修补,该模型关节面的最大位移为0.52 mm,而冠状突骨折不做固定,修补内侧副韧带的模型关节面的最大位移为0.51 mm;⑤上述结果显示,实验成功建立肘关节"恐怖三联征"的有限元模型,将1/3冠状突骨折做固定,如果不修补内侧副韧带,该模型关节面的最大应力及位移略小于正常模型的数值。而冠状突骨折不做固定,仅修补内侧副韧带,其肘关节模型关节面的最大应力及位移大于或基本等于正常模型的该数值。因此,在肘关节外侧柱稳定性重建的基础上,内侧副韧带能够取代冠状突骨折的固定,重建肘关节的稳定性。
BACKGROUND: The ?terrible triad injury" of the elbow joint is a serious complex fracture and dislocation. It is worthwhile to study on stability of the elbow joint by repairing the medial collateral ligament structure instead of the fixation of the coronal process.OBJECTIVE: To compare the mechanical value of different flexion angles of the elbow joint under two modes of fixing ulnar coronoid process and repairing medial collateral ligament based on the stability reconstruction of the lateral column of the elbow joint and to evaluate the effect of two surgical methods on the stability of the elbow joint by establishing a finite element model of the "terrible triad injury" of the elbow joint.METHODS: Using data of the elbow joint CT and MRI, command stream files were generated from the computer. The elbow joint solid model was established and meshed. To compare the elbow joint stability, by simulating whether the medial collateral ligament was repaired or not after fracture, and the coronoid process was fixed or not, longitudinal load was applied to analyze the stress distribution on the elbow joint surface under various working conditions.RESULTS AND CONCLUSION:(1) The maximum stress of the normal elbow joint surface was 0.78 MPa when the elbow joint was extended to 0°. If the 1/3 coronoid process fracture was fixed, and the medial collateral ligament was not repaired, the maximum stress of the articular surface of the model was 0.84 MPa. If the coronoid process fracture was not fixed, the medial collateral ligament was repaired, the maximum stress of the articular surface was also 0.84 MPa.(2) When the elbow joint was flexed 30°, the maximum stress of the articular surface of the normal elbow joint model was 2.02 MPa. If the 1/3 coronoid process fracture was fixed, and the medial collateral ligament was not repaired;the maximum stress of the joint surface was 2.02 MPa. If the coronoid process fracture was not fixed, the medial collateral ligament was repaired, and the maximum stress was 2.07 MPa.(3) The maximum displacement of the normal elbow joint surface was 0.14 mm when the elbow joint was straight. If the 1/3 coronoid process fracture was fixed, and the medial collateral ligament was not repaired, the maximum displacement of the articular surface of the model was 0.15 mm. If the coronoid process fracture was not fixed, the medial collateral ligament was repaired, the maximum displacement of the articular surface of the elbow joint model was 0.16 mm.(4) When the elbow joint was flexed30°, and the maximum displacement of the articular surface of the normal elbow joint model was 0.52 mm. If the 1/3 coronoid process fracture was fixed, and the medial collateral ligament was not repaired, and the maximum displacement was 0.52 mm. If the coronoid process fracture was not fixed, the medial collateral ligament was repaired, and the maximum displacement was 0.51 mm.(5) The above results show that the experiment has successfully established the finite element model of the "terrible triad injury" of the elbow joint. If the 1/3 coronoid process fracture is fixed, the medial collateral ligament is not repaired, and the maximum stress and displacement of the articular surface of the model were slightly smaller than those of the normal model. If the coronoid process fracture is not fixed, only the medial collateral ligament is repaired, and the maximum stress and displacement of the articular surface of the elbow joint model are greater or substantially equal to the values of the normal model. Biomechanical studies suggest that the medial collateral ligament can replace the fixation of the coronoid process fracture and reconstruct the stability of the elbow joint on the basis of the stability reconstruction of the lateral column of the elbow joint.
引文
[1]Hotchkiss RN.Fractures and dislocations of the elbow.In:Rockwood CA Jr,Green DP,Bucholz RW,Heckman JD,eds.Rockwood and Green?s Fractures in Adults.4th ed,Vol 1.Philadelphia,PA,USA:Lippincott-Raven.1996;929-1024.
[2]Chen NC,Ring D.Terrible triad injuries of the elbow.J Hand Surg Am.2015;40(11):2297-2303.
[3]Giannicola G,Calella P,Piccioli A et al.Terrible triad of the elbow:is it still a troublesome injury?Injury.2015;46(Suppl 8)S68-S76.
[4]Mazhar FN,Ebrahimi H,Jafari D et al.Radial head resection versus prosthetic arthroplasty in terrible triad injury:a retrospective comparative cohort study.Bone Joint J.2018;100-B(11):1499-1505.
[5]Pugh DMW,Wild LM,Schemitsch EH,et al.Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures.J Bone Joint Surg Am.2004;86(6):1122-1130.
[6]McKee MD,Pugh DM,Wild LM,et al.Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures:surgical technique.J Bone Joint Surg Am.2005;87(s1):22-32.
[7]Mellema JJ,Doornberg JN,Dyer GS,et al.Distribution of coronoid fracture lines by specific patterns of traumatic elbow instability.J Hand Surg Am.2014;39(10):2041-2046.
[8]Feng D,Zhang X,Jiang Y et al.Plate fixation through an anterior approach for coronoid process fractures:a retrospective case series and a literature review.Medicine(Baltimore).2018;97(36):e12041.
[9]刘仁浩,周楠,毕郑刚.尺骨冠状突骨折的修复策略及生物力学分析[J].中国组织工程研究,2013,21(43):7610-7617.
[10]Sard A,Dutto E,Rotini R,et al.The posterior bundle of the elbow medial collateral ligament:biomechanical study and proposal for a new reconstruction surgical technique.Musculoskelet Surg.2017;101(Suppl 2):181-186.
[11]Kovacevic D,Vogel LA,Levine WN.Complex elbow instability:radial head and coronoid.Hand Clin.2015;31(4):547-556.
[12]Hartzler RU,Llusa-Perez M,Steinmann SP et al.Transverse coronoid fracture:when does it have to be fixed?Clin Orthop Relat Res.2014;472(7):2068-2074.
[13]Morry BF,An KN.Stability of the elbow:osseous constraints.J Shoulder Elbow Surg.2005;1:174-178.
[14]Callaway GH,Field LD,Deng XH.Biomechanical evaluation of the medial collateral ligament of the elbow.J Bone Joint Surg Am.1997;8:1223-1231.
[15]Maloney MD,Mohr KJ,Attrache NS.Elbow injuries in the throwing athlete.Difficult diagnosis and surgical complications.Clin Sport Med.1999;4:795-809.
[16]Poelert S,Valstar E,Weinans H,et al.Patient-specific finite element modeling of bones.Proc Inst Mech Eng H.2013;227(4):464-478.
[17]Burkhart TA,Andrews DM,Dunning CE.Finite element modeling mesh quality,energy balance and validation methods:a review with recommendations associated with the modeling of bone tissue.J Biomech.2013;46(9):1477-1488.
[18]Doornberg JN,Ring D.Coronoid fracture patterns.J Hand Surg Am.2006;31(1):45-52.
[19]Jeon IH,Sanchez-Sotelo J,Zhao K,et al.The contribution of the coronoid and radial head to the stability of the elbow.JBone Joint Surg Br.2012;94:86-92.
[20]Pugh DMW,Wild LM,Schemitsch EH,et al.Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures.J Bone Joint Surg Am.2004;86(6):1122-1130.
[21]McKee MD,Pugh DM,Wild LM,et al.Standard surgical protocol to treat elbow dislocations with radial head and coronoid fractures:surgical technique.J Bone Joint Surg Am.2005;87(s1):22-32.
[22]Mathew PK,Athwal GS,King GJW.Terrible triad injury of the elbow:current concepts.J Am Acad Orthop Surg.2009;17(7):137-151.
[23]Labott JR,Aibinder WR,Dines JS,et al.Understanding the medial ulnar collateral ligament of the elbow:review of native ligament anatomy and function.World J Orthop.2018;9(6):78-84.
[24]Dodds SD,Fishler T.Terrible triad of the elbow.Orthop Clin North Am.2013;44(1):47-58.
[25]Hrubina M,Horak Z,Skotak M et al.Assessment of complications depending on the sliding screw position-finite element method analysis.Bratisl Lek Listy.2015;116(5):302-310.
[26]Aquilina P,Parr WC,Chamoli U,et al.Finite element analysis of patient-specific condyle fracture plates:a preliminary study.Craniomaxillofac Trauma Reconstr.2015;8(2):111-116.
[27]倪鹏辉,张鹰,杨晶,等.临床骨科中应用的有限元分析法:新理论与新进展[J].中国组织工程研究,2016,20(31):4693-4699.