i'd be leery of using an inflatable cast for any distance with a known leg fracture - unless it was a stable, lower leg fracture.

there are walking casts - remember tom brady pre-super bowl - but they are too bulky for edc. the inflatables are heavy plastic - think waterbed-type plastic. would wear out quickly.

depends too on how far you are going to walk. if it were a great distance i think the pain would stop you.

and the potential for further, permanent injury to the surrounding structures is too great.

IMHO i'd stabilize the suspected - hopefully not a compound (bone thru skin) fracture - and fashion a one-sided crutch, keeping the injured leg bent back at the knee and out of the way. make better time to the e.r.