In endemic goitre areas 20%of the population over 70 years old will have a retrosternal goitre. The definition of a retrosternal goitre varies with respective authors, there are four major definitions.
I started PT after 10 days and can straighten my leg, bend to a little past 90 degrees and walk without crutches three days before the 3 week post surgery mark.
After each surgery, my PS told me I could exercise gently, which meant I could walk at a pace of 2.5 miles/hour, for roughly two - four weeks afterwords. It just depends on how long it takes you to heal before you can really start exercising again.