19 Oct Textile Innovation for Surgical Robotics Applications
A growing geriatric population, rising chronic disease rates, and increased demand for less invasive surgical procedures are some of the major factors contributing to the adoption of automation in healthcare[i]. Incorporating robots in the operating room has enabled a shift away from open-surgery, and towards complex, high-precision procedures that can often be minimally invasive[ii]. Robotic surgery opens the possibilities for greater geometrical precision — which is especially beneficial for anatomical areas that are difficult for a human surgeon to access — and may result in shorter hospitalizations. Many leading medical device companies are investing in development of surgical robotics systems, and government organizations have ramped up funding to support robotics R&D efforts. The global surgical robotics market is anticipated to reach $12.6 billion by 2025, according to BIS Research[iii].
Textiles are proving to be a viable and advantageous alternative to traditional metal in robotic devices, thanks in large part to their ability to be thinner, lower profile, cost-effective, and to support better articulation. Incorporation of textiles into surgical robotics systems such as robotic arms enables greater flexibility and smoother movements. For a wide range of surgical applications requiring gripping, cutting or suturing, textiles can give the hand on a robotic device more degrees of freedom and improved orientation. Textiles are now commonly being used as tethers for actuators, and even as replacements for stainless steel wire in robotic-assisted laparoscopic staplers. Contrary to some misconceptions, transitioning from metal to textile components in robotic devices does not mean sacrificing strength – in fact, in some cases textiles using modern high-performance fibers can be even stronger than metals, while also having the flexibility to conform to twists, bends and grooves in a device.
In general, braided textiles usually prove to be ideal for balancing the size and strength requirements in robotic surgery platforms. Braids can bear significant weight, and the cylindrical shape makes them well-suited to wind through cannulas, a transcatheter delivery system, or to conform to twists and turns. Cortland Biomedical can customize the characteristics of different zones of a single braid – for example, enabling a high degree of flexibility at the distal end of a braid while being stable in the middle for maximum load bearing. Cortland Biomedical’s highly skilled hand fabrication capabilities can even create different splices, loops and end terminations that can be used with other braids or terminations within a robotic device. In some cases, a woven textile may be considered, particularly for covering a metal component in a robotic device. Wovens are inherently strong and resistant to deformation.
When designing a textile for a surgical robotics platform, a textile product developer should work closely with the medical device manufacturer to first understand exactly how the textile will be used. Specifications to establish early in the design process include what the surgical application is, whether there are any size constraints, and if there are any bends or grooves in the device. This will drive an informed recommendation regarding the textile configuration and, very importantly, the material selection. For example, when strength is key, ultra-high molecular weight polyethylene may be the best material choice, but if stability and chemical resistance are the top priority liquid crystal polymer (LCP) may be preferable.
To strike the right balance of size and strength of braiding parameters, the textile product developer should do extensive mechanical testing — including tensile strength, elongation, and diameter measurements. Textiles have much more compliant properties than metals in terms of torque, flexibility and strength. When looking to replace a metal with a textile, the textile should have limited elasticity. A high degree of elasticity can lead to deformation if components are loaded into a robotic device under tension and then left for long periods of time. Some of the elasticity in a braid can be removed by aligning films and yarns in a way that removes a lot of the constructional stretch, or a core can be put in to act as the load bearing member in the braid.
In conclusion, robotic platforms have the potential to bring greater precision and less invasive approaches to a huge variety of applications across general surgery, urology, orthopedics, gynecology, cardiovascular and more. From catheter insertion to cardiac ablation, by working alongside human surgeons in the OR, robots can help improve the result for the patient. As the surgical robotics industry continues to evolve and become more advanced, close collaboration between textile developers and medical device OEMs will result in greater innovation and the potential for better patient outcomes.
By Michelle Lishner, Development Engineer, Cortland Biomedical