改进型肱骨逆行旋入钉的生物力学测试及临床应用评估

背景：昆明医学院附属延安医院骨科设计的肱骨旋入式自锁髓内钉，多方面均优于现有国内外设计的带锁髓内钉，但顺行旋入式髓内钉与传统带锁髓内钉普遍存在肩袖损伤和肩关节功能活动障碍，而逆行旋入式髓内钉则彻底解决了这一难题。 目的：根据初期设计的逆行旋入钉存在的问题，结合肱骨解剖特点和临床实践，进行改进与完善工作，力图从根本上解决原逆行旋入钉髓内固定存在的若干问题，以利于进一步临床应用与推广。 方法：根据肱骨的解剖学特点，利用肱骨尸体标本进行相关生物力学测试。并应用改良后的逆行旋入钉治疗73例肱骨骨折患者，观察旋入钉与原型钉在抗轴向压缩、抗拉伸、抗扭转、抗弯曲方面的不同之处及生物力学测试结果和纳入患者的临床疗效。 结果与结论：改进后旋入钉在抗轴向压缩、抗拉伸、抗扭转、抗弯曲4个方面均优于原型钉，两者比较差异均有显著性意义(P < 0.01)。患者随访3~48个月，均愈合良好，置入后无感染、金属断裂、内固定松动等并发症。提示，改进型逆行旋入钉生物力学测试更合理，且操作简便，并发症少，具有广泛的临床应用前景及推广价值。

Biomechanical tests and clinical application evaluation of advanced humeral retrograde intramedullary nail

BACKGROUND:The humeral auto-locked intramedullary nail, designed by Yanan Hospital of Kunming Medical University, exhibits several advantages over previous domestic locked intramedullary nails. However, anterograde screwing-type intramedullary nail and traditional auto-locked intramedullary nail induce rotator cuff injury and dysfunction of shoulder joint. Retrograde intramedullary nail solves these problems. OBJECTIVE:To improve the retrograde intramedullary nail based on humeral bone dissection to benefit clinical application. METHODS:According to humeral bone anatomic characteristics, related biomechanical tests were performed using humeral samples from corpse. Retrograde intramedullary nail was used to treat 73 patients with fracture of humerus. The resistance of axial compression, extension, torsion, blending were compared, and clinical effects were observed. RESULTS AND CONCLUSION:The retrograde intramedullary nail exhibited advantages in resisting axial compression, extension, torsion, and blending compared with previous existed nails (P < 0.01). The patients were followed up for 3-48 months, and healed well. No infection, nail breakage, or loosening occurred. Results showed that the advanced retrograde intramedullary nail is reasonable in biomechanical tests, with simple operation, few complications. It should be used widely in clinic.