The shoulder is a complex joint–what does the research say is the weakest rotator cuff muscle and why?

Chris you ask a lot of broad questions when the answers are really multifaceted and complex. Are you asking which muscle is the most often injured out to the group of Supraspinatus, Infraspinatus, Teres Minor, and Subscapularis?

The weakest is totally dependent on the client’s history and activities. If I experienced a serious Teres Minor tear at some point and never had it evaluated or treated, that is most likely going to be the weakest of the group.