CAJ | 학술논문

背景：由于椎弓根毗邻结构的重要性，一旦置钉偏差损伤毗邻结构后果极为严重，虽然胸椎椎弓根-肋骨复合体置入螺钉的安全性明显大于椎弓根螺钉，但关于椎弓根-肋骨复合体应用不同截面积的螺钉的力学研究尚少有人涉及。 　　目的：分析中上胸椎椎弓根-肋骨复合体应用不同截面积螺钉的力学特征。 　　方法：取5具新鲜成人胸椎T 1-T 10标本及相连的一段肋骨(长50-60 mm)，以双功能骨密度测试仪测量椎体骨密度，排除骨质疏松椎体，同时行胸椎CT扫描。按照CT测量结果置入直径分别为5.5，6.0和6.5 mm的椎弓根螺钉，进行CT扫描证实螺钉的位置，生物力学测试机上测量每颗螺钉的最大拔出力。 　　结果与结论：38个骨密度正常的标本共分别置入25枚5.5 mm、25枚6.0 mm和26枚6.5 mm螺钉，由于螺钉破坏椎弓根-肋骨复合体和螺钉穿破椎体，共得出68枚螺钉最大拔出力结果，三者的最大轴向拔出力分别为(812.36±147.22) N，(868.64±160.48) N，(946.48±157.58) N，其中6.5 mm与5.5 mm螺钉的最大轴向拔出力的差异有显著性意义(P<0.05)。提示中上胸椎椎弓根-肋骨复合体中应用直径5.5 mm以上的椎弓根螺钉，可获得坚强的内固定，可满足临床内固定需要。
배경：유우추궁근비린결구적중요성，일단치정편차손상비린결구후과겁위엄중，수연흉추추궁근-륵골복합체치입라정적안전성명현대우추궁근라정，단관우추궁근-륵골복합체응용불동절면적적라정적역학연구상소유인섭급。 　　목적：분석중상흉추추궁근-륵골복합체응용불동절면적라정적역학특정。 　　방법：취5구신선성인흉추T 1-T 10표본급상련적일단륵골(장50-60 mm)，이쌍공능골밀도측시의측량추체골밀도，배제골질소송추체，동시행흉추CT소묘。안조CT측량결과치입직경분별위5.5，6.0화6.5 mm적추궁근라정，진행CT소묘증실라정적위치，생물역학측시궤상측량매과라정적최대발출력。 　　결과여결론：38개골밀도정상적표본공분별치입25매5.5 mm、25매6.0 mm화26매6.5 mm라정，유우라정파배추궁근-륵골복합체화라정천파추체，공득출68매라정최대발출력결과，삼자적최대축향발출력분별위(812.36±147.22) N，(868.64±160.48) N，(946.48±157.58) N，기중6.5 mm여5.5 mm라정적최대축향발출력적차이유현저성의의(P<0.05)。제시중상흉추추궁근-륵골복합체중응용직경5.5 mm이상적추궁근라정，가획득견강적내고정，가만족림상내고정수요。
BACKGROUND:Due to the importance of pedicle adjacent structures, once the screw replacement appears a deviation, adjacent structures may be damaged, leading to extremely serious consequences. Although the security of screw placement in thoracic vertebral pedicle-rib complex is significantly greater than that of pedicle screws, the mechanics of the pedicle-rib complex at different cross-sectional areas of the screw are rarely reported. OBJECTIVE:To observe mechanical property of different cross-sectional area screws in the middle and upper thoracic vertebral pedicle-rib complex. METHODS:Five specimens of adult cadaveric thoracic spine (T 1-T 10 ) and adjacent rib segment (50-60 mm long) were used. The bone density of specimens was measured using difunctional bone density testing machine, and osteoporotic vertebral body was excluded. The position of the screws was detected with CT images. The maximal withdrawal force of the pedicle screw was measured with biomechanical force test machine. RESULTS AND CONCLUSION:Thirty-eight specimens at normal bone density were implanted with 25 screws (5.5 mm), 25 screws (6.0 mm) and 26 screws (6.5 mm). Because the pedicle screws destroyed the pedicle-rib complex and perforated the vertebral body, we final y obtained the withdrawal force of 68 screws. The axial withdrawal force of pedicle screws at different diameters was (812.36±147.22) N, (868.64±160.48) N and (946.48±157.58) N, respectively. There were significant differences between the 5.5 mm screws and the 6.5 mm screws (P<0.05). Experimental findings indicate that, the pedicle screws (diameter>5.5 mm) are suitable in the middle and upper thoracic vertebral pedicle-rib complex due to strong internal fixation and clinical requirement.