Given a choice between the two – acupuncture. Acupuncture is particularly good for that sort of injury. And as it happens, I'm receiving acupuncture on a weekly basis for shoulder problems at the moment. When I mentioned the problem to my GP he said "stretch exercises" and left it at that. 3 sessions of acupuncture, and my shoulders are almost completely sorted – and that's after many months of the problem. If you do go for acupuncture, I strongly advise you avoid medical stuff who have been on an "acupuncture course" – go to a traditional Chinese doctor…..in the same way that you would buy a curry in an Indian restaurant and not a pizzeria.
NB, many years ago I was told I needed an operation due carpal tunnel syndrome in my left arm, 3 sessions of acupuncture cured it 100% and it never returned.