Department of Orthopaedics, University of Munich, Grosshadern Campus, Munich, Germany.
Pain Physician. 2012 Jan-Feb;15(1):E89-97.
The epidural lysis of adhesions (ELOA) procedure supposedly has a biomechanical component in addition to the targeted injection of medications into the epidural space. It is assumed that the catheters used for the ELOA procedure can release epidural scars and adhesions.
To evaluate the possible biomechanical effects of the typically used catheters and to put these effects into clinical perspective.
Experimental study.
The biomechanical laboratory of an academic orthopedic surgery department.
Experimental setups were devised that allow for the measurement of the 3 main forces that can be exerted by manipulating a catheter in the epidural space or by injecting fluids through such a catheter: axial forces, torsional forces, and hydraulic effects.
The maximum axial forces measured under extremely tight catheter guidance were 7 newton (N), whereas the maximum forces under conditions that more likely reflect a real treatment situation were between 1 and 2 N. The maximum torsional forces measured were 0.3 N under extremely tight catheter guidance and 0.01 N under more realistic conditions. The maximum flow that could be achieved through the typical catheter using normal saline and the maximum possible thumb pressure onto a 5 mL or a 10 mL Luer-Lock syringe was 0.48 mL/ s. Given these results and other data available to us, it appears impossible that the ELOA procedure with typically used catheters has any relevant mechanical effect.
Like with any experimental study, the realities of an in vivo situation can only be modeled to a limited degree. The main limitation of our study is that we cannot calculate, measure, or simulate neither the flow resistance between an epidural adhesion pocket and the open, local epidural space nor the flow resistance between the open, local epidural space and the larger epidural space as well as the retroperitoneal space.
According to our findings and arguments, the ELOA procedure is predominantly a method for the highly targeted application of epidural medications and possibly also has a lavage effect. A mechanical lysis of scars or adhesions appears unlikely.
硬膜外松解粘连（ELOA）手术除了将药物靶向注射到硬膜外腔外，据称还有一个生物力学成分。人们认为，用于 ELOA 手术的导管可以释放硬膜外疤痕和粘连。
评估通常使用的导管的可能的生物力学效应，并将这些效应置于临床角度进行考虑。
实验研究。
学术骨科手术系的生物力学实验室。
设计了实验装置，可测量通过在硬膜外腔中操作导管或通过此类导管注射流体而施加的 3 种主要力：轴向力、扭转力和液压效应。
在极其紧密的导管引导下测量到的最大轴向力为 7 牛顿（N），而在更能反映实际治疗情况的条件下的最大力为 1 至 2 N。在极其紧密的导管引导下测量到的最大扭转力为 0.3 N，在更现实的条件下为 0.01 N。使用生理盐水可通过典型导管达到的最大流量以及使用正常拇指压力对 5 mL 或 10 mL Luer-Lock 注射器施加的最大压力为 0.48 毫升/秒。根据这些结果和我们掌握的其他数据，似乎不可能通过通常使用的导管进行 ELOA 手术具有任何相关的机械效应。
像任何实验研究一样，只能在有限程度上对体内情况进行建模。我们研究的主要限制是，我们既无法计算、测量，也无法模拟硬膜外粘连囊中与开放的局部硬膜外空间之间的流动阻力，也无法模拟开放的局部硬膜外空间与更大的硬膜外空间以及腹膜后空间之间的流动阻力。
根据我们的发现和论点，ELOA 手术主要是一种高度靶向应用硬膜外药物的方法，并且可能还具有冲洗效果。疤痕或粘连的机械松解似乎不太可能。
