Large Breed Longevity. The average lifespan of all dogs -- both small and large -- is 12.8 years, reports pets.ca, a Canadian pet information provider. Some larger dogs tend not to live that long, and data varies considerably by breed.
Aching Legs. Aching Legs and Feet. Injury is the most common cause of leg pain (aching legs). However, even a simple back pain can cause your legs to ache depending on the degree of pain. Usually, elders and diabetics and people with poor circulation are the ones who experience leg pain especially at night.
Generally, leg pain refers to any pain that develops between your feet and your pelvis. To make matters even more complicated, the cause of leg pain may not even be due to a problem with your leg. For example, some spine disorders can cause leg pain. Leg pain may be acute or chronic. Onset may be sudden or gradual.