What is an eatable to use after knee replacement surgery?

A wide variety of edibles are available. Be careful with dosing, as a small brownie or cookie can be very potent and cause strong psychoactive effects. Edibles are more difficult to dose than inhaled cannabis. I might suggest a small portion of a chocolate bar or a whole plant tincture extract with CBD and THC. The tincture is applied under the tongue, and is absorbed through the mucous membranes directly into the bloodstream. Effects should occur within 30 minutes and last for several hours.