What does is the glenohumeral joint and what does it do? (ANATOMY)

Glenohumeral joint arthritis is caused by the destruction of the cartilage layer covering the bones in the glenohumeral joint. This creates a bone-on-bone environment, which encourages the body to produce osteophytes (bone spurs). Friction between the humerus and the glenoid increases, so the shoulder no longer moves smoothly or comfortably

For me a person with a phd and who knows what there talking about.i know the chances of a radiation leak is low but if it does the area within a 96.3 mile radius would be unusable because of contamination