Alex wears this shirt by Working Style, and it is a classic shirt with buttons down the centre which runs from below the collar until the hem of the shirt, this shirt is roomy and would not be restrictive if you were pushing your mobility aids. The cuffs at the hem of the sleeves keep the fit to the arm slimming, still roomy, yet not too wide that it would be annoying if you were pushing your wheelchair.
The buttons down the center and at the collar are standard size, and if you struggle with dexterity, you might prefer some help with these. As for getting on and off, this shirt is cotton and as previously mentioned is roomy, accordingly, you will have some space to move the shirt around you to get your arm in.
If you struggle with leaning forwards out of your wheelchair, you might prefer another kind of shirt – as you would need to lean forward to get this around you.