*sigh* I’ve already made an addition but this idea is SO under-explored. So please also consider:
The literally limitless possibilities for prosthesis, including having a character stand on their flying prosthetic foot in order to fly/levitate, prosthesis that remains awake while they sleep and can defend them in the night, prosthesis that looks completely real but is just packed with compartments, prosthesis that functions precisely like a real limb and is directed normally by the brain, invisible prosthesis, magnetized steampunk prosthesis, limb prosthesis that is basically a floating hand/foot with the limb between missing- like, can’t be touched missing,
A full menagerie of mythical beasts that can serve as service animals, up to and including keeping the soul in the body while waiting for healers to arrive so that the heart can be re-started much longer after it has stopped beating. Some mythical birds were said to steal nightmares and fly away with them as well.
Horse-sized intelligent dragons used as mobility aids
Chariot/chair/wheelchair mobility aids that levitate and/or move quickly
Emergency communication devices that will alert the other holders of a crisis with location and specifics even when you’re is unconscious, such as with epilepsy or passing out from low blood sugar
Hearing aids/glasses that not only aide impaired hearing/vision, but also allow the user to hear/see in other specified places in the world
Magical devices that stimulate dead nerves in cases where a limb goes dead, reducing the need for amputation
Similar magical devices that straight-up reanimate dead limbs, so that you can leave your arm lying around and still use it when you walk away (so much plot opportunity, SO much)
Magical capsules you can swallow that give you lots of healthy energy, which can be used for various disorders that lead to fatigue but can also be used as a first aide to aide healing of wounds/illness
Pill cases that remember what you need to take and what you’ve actually taken and WILL get in your face if you’ve forgotten
Capsules or spells for cleanliness that reduces the need to bathe for those for whom it’s difficult
House plants that release chemicals your brain SHOULD be producing so that you breathe it in- possibly in conjunction with medication that helps to regulate so you don’t overdose on serotonin what you’re trying to sleep
Plants you can eat that will literally replace your compromised immune system
A ritual that will take a magical 3D photograph of your current physical condition, and, if you’ve taken one, you can use this complicated spell to have your physical body go back and become exactly what it was at that point- like a computer backup.
Many, many options for spells, healing herbs and rituals that will ease chronic pain