Metamaterial for tuneable compressive response in prosthetic liners

Prosthetics have reformed the lives of leg amputees, but pressure-related problems (discomfort and skin breakdown) are still a significant concern. The prosthetic socket, where the residual limb sits, is a critical interface between the residual limb and the prosthesis. A liner (cushioning material) is worn over the residual limb to reduce movement and chafing between the skin and the socket [1]. For optimal wearing comfort, bony areas of the stump ideally require soft liner material while areas of the stump with soft tissue need a stiffer material. In this study, it is shown that mechanical metamaterials can be used to tune the compressive properties of a material by creating unit cells of different shapes and sizes.