Welcome at HCM.
I can understand your concerns.
It looks from your details that your husband has deep vein thrombosis
in his leg vein.As THIS DVT is more then 2 months old so it comes in category of CHRONIC DVT. At this stage this DVT scarred the vein of leg.There is opening of minute blood vessel channels after blockage of large veins these opening channels are not sufficient to maintain the venous outflow.This insufficiency is the reason for swelling after use of limb.
At this stage only treatment which can be helpful is ,stent
surgery.In this surgeon puts a stent through the organized clot & through which blood flows start to flow again in blocked vessel.After this surgery he will be kept on anticoagulant
medicines for few months.
Hope this all will help you.
With best wishes.