MINIATURE ACTUATOR FOR BONE LENGTHENING/TRANSPORT SYSTEM

目前用于骨延长和骨运输过程的技术主要依赖于用于骨段的固定和移动的横向销或线。这些针和线导致显著的发病率，特别是疼痛、瘢痕形成、局部关节活动度丧失和针部位感染。提出了一种线缆致动器，其将消除贯穿线或针的经皮穿透以及相关的疼痛、疤痕、挛缩和感染风险。该致动器将使一个实用的，完全植入式牵引装置的应用，骨延长和骨运输程序。为了确保植入系统的临床成功，致动器必须是小型的、自供电的、自动的（在没有患者主动参与的情况下致动）和可控的（提供外部临床控制和编程的方法）。第一阶段将开始致动器的开发，并将建造和测试几个能够产生1200 N可控牵引力的工程原型。在第二阶段，将开发和测试最终形式的致动器。该装置将占用不到100 cc，由一个小型集成电池供电，并通过无线电发射机进行传输。拟议的商业应用：每年约有15，000至20，000例手术用于替换或再生超过2.5 cm长的缺失骨段。每年大约有6,000例肢体延长手术。其中约三分之一将成为该系统的候选人。与其他方法相比，所提出的设计是有利的，因为该机构相对于骨位于远处，力由线缆传递。因此，可以植入标准髓内棒，并且该系统可以应用于任何适合棒固定的骨。

Current techniques for bone lengthening and bone transport procedures rely primarily on transverse pins or wires for fixation and movement of the bone segments. These pins and wires are responsible for significant morbidity, specifically pain, scarring, loss of motion in regional joints, and pin site infection. A cable actuator is proposed that will eliminate percutaneous penetration of transfixing wires or pins and the associated pain, scars, contractures, & risk of infection. This actuator will enable a practical, fully implantable distraction device for application to bone lengthening and bone transport procedures. To ensure clinical success of the implant system, the actuator must be small, self-powered, automatic (actuate without active patient participation), and controllable (provide means for external clinical control and programming). Phase I will begin development of the actuator, and several engineering prototypes capable of generating a controllable distraction force of 1200 N will be built and tested. In Phase II, a final-form actuator will be developed and tested. This device will occupy less than 100 cc, be powered by a small, integrated battery, and be directed transcutaneously by a radio transmitter. PROPOSED COMMERCIAL APPLICATIONS: Approximately 15,000 to 20,000 procedures are performed annually to replace or regenerate missing bone segments over 2.5-cm long. There are about 6,000 limb lengthenings performed annually. About one-third of these would be candidates for this system. The proposed design is advantageous compared to other approaches because the mechanism is located remotely, relative to the bone, with the force transmitted by a cable. Therefore, a standard intermedullary rod can be implanted, and the system can be applied to any bone amenable to rod fixation.