I need to split my mom's gowns in the back. What is a good way to close it without causing discomfort to her back?

We got mom some knee length sleep shirts made of t-shirt material. Then we cut them right up the back to the band at the neck but not through the band. That held it in place. We didn't even hem the cut edges-just left them raw because then she wouldn't even feel the edges under her. It worked really well and it was so easy to change gowns--just slip the neck band over her head and slip her arms into the sleeves.