Do you know what a rotator cuff is? For those who do, fabulous! Maybe you're a baseball fan or an anatomist. For those who don't, this is the group of muscles and their tendons that move your shoulder joint. When I was cutting up cadavers, we used the mnemonic SItS to remember what comprises the rotator cuff. That stands for subscapularis, infraspinatus, supraspinatus, and teres minor (that's why the t is lower case, because there's also a teres major), four muscles related to the scapula. All of them insert into the proximal part of the humerus, the upper arm bone, and along with the scapula and the clavicle, comprise the shoulder joint. The shoulder joint itself is also rather interesting as it is really a compromise between flexibility and stability, and its flexibility may also be what accounts for the surprisingly high number of injuries and chronic problems that occur here. As Rick and I discuss on PodMed this week, that may be as many as one in seven people older than 70, according to this paper in JAMA! Culpa mea! I had no idea it was so very common, and that's why I decided to write about it this week.
The paper is really an expose of what clinicians should look for and how they should evaluate people who come to them complaining of shoulder pain, and that's between 7 and 26% of the population at any one time, based on extensive meta-analysis. The authors state that complaints about pain in this joint are the third most-common reason people seek medical help for a musculoskeletal problem, and they use the acronym RCD, for rotator cuff disease, to describe it. Wow. It's even a disease! In an interesting series of case studies, video and illustrations, they delineate the different types of injuries or chronic problems that comprise RCD and how to distinguish them one from another. Rather than do so here I'll simply refer clinicians to the article, but the good news is, they're all low-tech and can be accomplished in an office visit.
The major symptom of RCD is pain, in particular when the arm is raised overhead. In their extensive discussion the authors indicate that while many people are referred to specialists for evaluation, their assertion is that with practice, primary care physicians should be perfectly capable of evaluating RCD using their algorithm. That's good news for the large number of folks with RCD, who might not have to shop their injuries to find out what's wrong. One thing I would like to have seen in the article is what people can do about it once they're diagnosed, but I guess that's a topic for another article.
Other topics this week include screening for peripheral artery disease or PAD in Annals of Internal Medicine, steroid injections for carpal tunnel syndrome in the same journal, and overdiagnosis of thyroid cancer in the BMJ. Until next week, y'all live well.