Patients that are your age and are already developing hammertoes should certainly only wear shoes with a deep and wide toe box and also shoes with stretchable material over the toes. There are a wide array of choices as far a brands are concerned. Orthofeet and Aetrex are some examples that have men's and women’s shoe gear. As far as athletic shoes are concerned, I would use a brand you are comfortable with that has options with a stretchable and accommodating toe box.
I hope this helps! Have a great day.
Jonathan M. Kletz, DPM