What causes impingement?

What causes impingement? So impingement is a chronic condition which is very common, more common in the over 40s, becomes increasingly common. Although the onset or the widespread use of handheld phone devices and laptops and computers has led to an increase in impingement in the younger age group as well now. But it's a chronic condition, more related I think to posture. There are other factors including smoking and poor conditioning of the patient in general can lead to an increased incidence of impingement, but certainly environment or the use that we put the arm and shoulder to has a part to play.