How to add context information to U-Net input


I have contextual information in addition to my input image with its corresponding segmentation mask (in my case the contextual information is the absolute body height in which the CT slice is positioned).

I want to add this information to the input, so my U-Net can learn the expected size and type of organs in this body height and use this to improve segmentation.
How can I add this scalar to the input image? As a an additional channel?

Thanks for the help.