弹性髓内钉技术的力学原理与应用原则  

Mechanical characteristics and application principle of flexible intramedullary nail

作　　者：杨建平[1] Yang Jianping(Department of Pediatric Orthopaedics,Tianjin Hospital,Tiajin 300211,China)

机构地区：[1]天津市天津医院小儿骨科,300211

出　　处：《中华骨科杂志》2021年第21期1583-1588,共6页Chinese Journal of Orthopaedics

摘　　要：弹性髓内钉技术是目前国内外治疗儿童四肢长骨干闭合性骨折的首选方法。弹性髓内钉由钛合金材料制成,具有可塑性和内在的弹性,负重时不易断裂。术前应根据健侧骨干全长X线片测量骨干的直径和长度,将弹性钉预弯成"C"形,然后经骨干近端或远端内外侧皮质打入髓腔,依靠其内在的弹性在入钉点、"C"形的顶点和钉尖部位构成三点固定,使骨折端的应力达到平衡,形成髓内支架,骨干周围的肌肉组成软组织框架,达到相对稳定的生物学固定。正确地预弯两枚弹性钉的"C"形弧度、选择适宜的粗细和入钉点位置,使弹性钉在髓腔内占据的空间最大,同髓腔内壁接触的距离最长可有效抵抗横向、轴向和旋转不稳定;同时,钉尖和钉尾在干骺端张开分离的间距越大,抗扭转畸形的效果越好。在手术操作过程中,有效的闭合整复骨折、正确的弹性钉打入方法、钉尾的正确处理以及术后适当的外固定也是弹性髓内钉技术的关键。For long bone closed fractures in children,flexible intramedullary nail technique is the preferred technique domestically and abroad.The flexible intramedullary nail is made of titanium alloy material with satisfied plasticity and inherent elasticity,which is not easy to break with load bearing.Before operation,the diameter and length of the diaphysis should be measured according to the X-ray film of the uninjured side in full length.Further,the elastic nail should be pre-bent into"C"shape and then insert the medullary cavity through the proximal or distal medial and lateral cortex of the diaphysis respectively.Thus,a three-point fixation at the entry point with"C"shaped apex and the nail tip is developed based on the elasticity of the nail.The stress at the fractures is balanced and the intramedullary stent is formed,consequently.The muscles around the diaphysis constitute a soft tissue framework,which can achieve relatively stable biological fixation.The flexible intramedullary nail can provide appropriate pre-bending of two"C"shape elastic nails,optimal thickness and accurate insertion point position,and the larger the space occupied by the elastic nail in the marrow cavity with longer contact distance with the inner wall of the marrow cavity,Thus,the fracture side with flexible intramedullary nail can resist transverse,axial and rotational instability effectively.Meanwhile,the larger the gap between the tip and tail in epiphyseal is,the better the effects of anti-torsion deformity are.During the surgical procedure,effective close reduction of the fracture,correct way of elastic nail insertion,proper nail tail management and postoperative appropriate external fixation are the tips of elastic intramedullary nail technology.

关 键 词：弹性髓内钉 闭合性骨折 弹性钉 骨折端 生物学固定 旋转不稳定 干骺端 近端 

分 类 号：R726.8[医药卫生—儿科]