May T C, Krause W R, Preslar A J, Smith M J, Beaudoin A J, Cardea J A
Orthopedic Biomechanics Laboratory, Medical College of Virginia, Richmond.
J Arthroplasty. 1990 Mar;5(1):19-27. doi: 10.1016/s0883-5403(06)80005-7.
The revision rate of total hip arthroplasty has increased dramatically over recent years, leading to different methods of extraction of the femoral cement mantle to reduce operative time and surgical risks. The use of high-energy shock waves produced by the Dornier HM.3 Lithotripter to interrupt the cement-bone interface and to reduce the material properties of the cement is investigated. Tests were conducted to measure the pull-out strength of cemented treated rods versus untreated rods, from the medullary canal of canine femurs. The treated femurs showed an average reduction in pull-out strength of 43%. An investigation involving the material properties of acrylic bone cement was also conducted. The properties tested were the compressive modulus of elasticity, the ultimate compressive strength, the ultimate tensile strength, and fracture toughness. The scanning electron microscope aided in determining whether microfractures in the cement resulted from the shock wave treatment. A theoretical study utilizing the finite element method was used to investigate areas of select shock wave treatment about the femoral prosthesis. Analysis of the results showed that the lithotripter treatment had no significant effect on the compressive properties but reduced the tensile properties and fracture toughness significantly. Scanning electron microscopy uncovered definite areas of induced microfractures not present in the control specimens. This study supports the concept of clinically noninvasive, preoperative shock wave treatment prior to total hip revision.
近年来，全髋关节置换术的翻修率急剧上升，这导致了不同的股骨骨水泥壳取出方法，以减少手术时间和手术风险。人们研究了使用多尼尔HM.3体外冲击波碎石机产生的高能冲击波来中断骨水泥与骨的界面，并降低骨水泥的材料性能。进行了测试，以测量经骨水泥处理的棒材与未经处理的棒材从犬股骨骨髓腔中的拔出强度。经处理的股骨拔出强度平均降低了43%。还对丙烯酸骨水泥的材料性能进行了研究。测试的性能包括压缩弹性模量、极限抗压强度、极限抗拉强度和断裂韧性。扫描电子显微镜有助于确定骨水泥中的微裂纹是否由冲击波处理引起。利用有限元方法进行的理论研究用于研究股骨假体周围选定冲击波治疗的区域。结果分析表明，碎石机治疗对压缩性能没有显著影响，但显著降低了拉伸性能和断裂韧性。扫描电子显微镜发现了对照标本中不存在的明确的诱导微裂纹区域。本研究支持在全髋关节翻修术前进行临床无创、术前冲击波治疗的概念。
