Yes, I have an indentation kind of between my bicep and deltoid muscles on my left arm . It s the size of a quarter. I noticed it about 2 months ago. It didn t hurt or anything. And it s very slightly discoloured. Almost looks like a scar . But for the past week now, I ve been having mild aches and pains going on in the same arm. Some days it aches, and some days it doesn t. It s really freaking me out. My friends all tell me that it might be a torn muscle. But I really don t remember hurting my arm. Although, at the beginning of this year, I pulled a muscle in my upper back, kind of between my shoulder blades. Would that have anything to do with this indentation that just appeared out of nowhere??