Fell off my horse yesterday. doc thinks a potential torn rotator cuff. waiting a week or 2 to do imaging to see if it resolves. would a sling help?

Sling OK as needed: A sling is only necessary if it allows you t get around easier without fear of doing further damage based on your surroundings and environment. A sling unweights the arm and allows your strained deltoid muscles to "take a break". Once your outer deltoid muscles can efficiently hold your arm in position, the sling becomes superfluous. Rehabilitation to regain motion and function can then begin.