The swelling and eschar (scab) are both indicative that there is a localized infection in the distal portion of her hallux. If you wish to treat this yourself, first step may include soaking the toe in either warm Epsom salt water or dilute antiseptic baths such as chlorhexidine. By doing that, you'll loosen the eschar, and kill any bacteria present on the surface. After the area is loose and pliable, you can take a pair of tweezers, and a scalpel, and try to work out the eschar until full debridement has been achived.
In most cases, behind the eschar, there is caseous material and puss in which attempts to squeeze out the material would be recommended. The open tissue can be packed with an antibacterial ointment or Manuka honey.
Being that the area is so localized, it's likely your hen is suffering from something else internally creating the paralysis you're seeing. Viral, bacterial diseases, trauma, toxicosis, are some reasons a chicken may go lame.