Mike,

Here's an explanation from the web:

Quote
Bone spurs develop most often in parts of the body where bone rubs against bone. Some doctors say this is a part of the normal aging process; that it's the body's way of compensating for worn-down cartilage and bone loss, which occurs due to osteoarthritis. Essentially, the body tries to repair the worn-down cartilage and bone loss by forming a new bone.


So, in my case when lifting or moving my arm past a certain point the new growth of bone around the joint causes pain and it from moving any further.

The Doctor told me it's common for people that spend a lot of time working overhead.


Bill