Churchill D L, Incavo S J, Uroskie J A, Beynnon B D
McClure Musculoskeletal Research Center, Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington 05405-0084, USA.
Clin Orthop Relat Res. 2001 Dec(393):335-44. doi: 10.1097/00003086-200112000-00039.
Adequate bone cement pressurization is critical in obtaining optimal femoral cement mantles during total hip arthroplasty. Pressurization can be generated during insertion of the femoral stem into the cement-filled canal. This may be clinically useful in augmenting conventional cement gun pressurization. Two factors, which were expected to influence the amount of insertion-induced pressurization, are the cement's cure state (viscosity) at the time of insertion and the femoral stem profile. This study evaluated the effect of these factors on cement pressurization during stem insertion. Femoral stems were inserted at a controlled rate into a reusable, simulated femoral canal. Intramedullary pressures were monitored at four locations along the canal's medial midline. The intrusion factor quantity, which accounts for pressure magnitude, duration of pressurization, and cement viscosity, was developed to quantify pressurization. Stem insertion into late cure stage (high viscosity) cement resulted in significantly higher intramedullary pressures (as much as 187% higher) and intrusion factors (as much as 43% higher) as compared with early stage (low viscosity) cement. The highest pressures and intrusion factors were found in the distal canal. A tapered stem profile resulted in significantly higher pressures (as much as 65%) and higher intrusion factors (as much as 63%) than a straight stem.
在全髋关节置换术中，充分的骨水泥加压对于获得最佳的股骨骨水泥固定层至关重要。在将股骨柄插入充满骨水泥的髓腔时可产生加压。这在增强传统骨水泥枪加压方面可能具有临床实用性。预计会影响插入诱导加压量的两个因素是插入时骨水泥的固化状态（粘度）和股骨柄的外形。本研究评估了这些因素对柄插入过程中骨水泥加压的影响。以可控速率将股骨柄插入可重复使用的模拟股骨髓腔。沿髓腔内侧中线的四个位置监测髓内压力。开发了侵入因素量来量化加压，其考虑了压力大小、加压持续时间和骨水泥粘度。与早期（低粘度）骨水泥相比，将柄插入晚期固化阶段（高粘度）骨水泥会导致显著更高的髓内压力（高达187%）和侵入因素（高达43%）。在远端髓腔发现了最高的压力和侵入因素。与直柄相比，锥形柄外形导致显著更高的压力（高达65%）和更高的侵入因素（高达63%）。
