Mermelstein L E, Chow L C, Friedman C, Crisco J J
Department of Orthopaedic Surgery and Rehabilitation, Yale University School of Medicine, New Haven, Connecticut, USA.
J Orthop Trauma. 1996;10(1):15-20. doi: 10.1097/00005131-199601000-00003.
The ability of calcium phosphate cement (CPC) to reinforce cancellous screws placed in previously stripped holes was studied in vitro. The distal end of canine femurs were harvested. A total of 15 screws were placed in six femurs. The pullout strength (failure force), failure displacement, stiffness, and energy absorbed were determined for the screws in the intact cancellous bone. Next, these stripped screw holes were packed with CPC. The pullout test was repeated, and the results were compared using a paired, Student's t test. We found that the CPC was able to reinforce the previously stripped holes and significantly increase the pullout strength (1,159 +/- 278 N versus 678 +/- 297 N) and the stiffness (1,990 +/- 569 N/mm versus 1,519 +/- 609 N/mm) of the constructs, as well as the energy absorbed by the constructs until failure (467 +/- 180 N.mm versus 278 +/- 140 N.mm). There was no difference in the failure displacement (0.94 +/- 0.23 versus 0.85 +/- 0.51 mm). This study documents the ability of CPC to acutely reinforce cancellous bone screws in a region with no or poor-quality cancellous bone.
对磷酸钙骨水泥（CPC）增强置于先前已剥离骨孔中的松质骨螺钉的能力进行了体外研究。采集犬股骨远端。在六根股骨中总共置入15枚螺钉。测定完整松质骨中螺钉的拔出强度（破坏载荷）、破坏位移、刚度和吸收能量。接着，用CPC填充这些已剥离的螺钉孔。重复拔出试验，并采用配对t检验比较结果。我们发现，CPC能够增强先前已剥离的骨孔，显著提高构建体的拔出强度（1159±278N对678±297N）和刚度（1990±569N/mm对1519±609N/mm），以及构建体直至破坏时吸收的能量（467±180N·mm对278±140N·mm）。破坏位移无差异（0.94±0.23对0.85±0.51mm）。本研究证明了CPC在无松质骨或松质骨质量差的区域急性增强松质骨螺钉的能力。
