Do NOT scrub the legs...this can cause bleeding which will inevitably lead to infection if you do not apply betadine or an antibiotic ...you should soak the legs to loosen any debris from the leg mites..then apply castor oil or vaseline...a thread I just read suggested castor oil as it has antibacterial properties ...the main thing is that you recognise that there is a scaley leg mite problem and treatment although it can take quite some time to treat is effective.
Do treat the areas up to where the feathers are on the legs..reapply frequently massaging the oil in an upwards direction..this will smother any mites under the scales...it is also recommended to treat the head area and comb as the mites can also affect this area... wishing you and your flock a mite free future!