By Jonathan Chu, MD
Interventional Pain Medicine
PM&R

So maybe your shoulder has been hurting, and your doctor has told you that your pain is coming from something called the rotator cuff.

However, a lot of my patients were often unsure about what the rotator cuff actually is, and why it could cause them so many problems.

Thus, in this video, I’m going to explain exactly what your rotator cuff is, why it can hurt, and the general steps you can take to rehabilitate your rotator cuff and get out of pain.

First of all, let’s start with the anatomy, as I would always tell the med students and residents rotating with me that, when it comes to pain medicine, if you understand the anatomy and structure, you’ve already won half the battle.

First, it is important to know that the rotator cuff is not on the outside of the shoulder, but is actually a structure that is below the superficial muscles.

In more specific anatomical terms, you would say that the rotator cuff is actually deep to the deltoid muscle, which is the big, quadrilateral shaped muscle on the outside of the shoulder that bodybuilders love to work on.

In the simplest terms, the rotator cuff is just a set of four key muscles and their tendons.

Though these muscles are quite small, they are extremely important, and serve the vital function of holding your humerus, or upper arm bone, in its socket, which is also known as the glenohumeral joint.

Thus, if your rotator cuff didn’t exist, your upper arm would have trouble staying in the socket, as the rotator cuff and joint capsule are really the main structures holding your upper arm in place. As a quick aside, this is the reason why shoulder instability is a potential, though uncommon, complication of massive rotator cuff tears.

And thus, if you study the structure of the rotator cuff and the rest of the shoulder, you’ll see that it is not necessarily the most stable joint in the human body. However, there’s a reason that the shoulder was designed this way: this distinctive structure makes your shoulder the most mobile joint in the entire body, and allows for immense freedom of movement, which is why under normal circumstances, you can move your arms a full 180 degrees above your head with no problems whatsoever.

Now, let’s take a closer look at these 4 vital muscles that make up the rotator cuff.

They are often known as the SITS muscles, because the acronym encompasses the first four letters of all of the muscles.

Let’s go through them.

The first, and most important muscle, is known as the supraspinatus. The name is quite apt, because it really describes exactly what it is.

Let’s break down the latin. Supra, means above, and then spinatus, refers to the spine of the scapula, which is one of the main bones of your shoulder. So, supraspinatus simply means muscle that sits directly above the spine of the scapula. The muscle starts in the scapula, in a bony hollow known as a fossa, and then runs underneath this important bony structure known as the acromion (which is going to be very important later), and then attaches to a large tubercle on the humerus, which is your upper arm bone.

Where the muscle originates and where it inserts is extremely important, because it tells us what the function of the muscle is: which is abduction.

Now the anatomical term is actually quite similar to the colloquial usage. For example, alien abduction means to be taken away (by aliens lol). The anatomical term is similar, in that it means that the muscle moves the arm away from the body. The supraspinatus is most important for the first 15 degrees of movement, and afterwards it really is the much bigger deltoid muscle that does the majority of the work.

The next letter in the acronym is I, which stands for infraspinatus. Now, breaking down this term: infra is Latin for below, and spinatus again refers to the spine of the scapula, so this word means muscle that is below the spine of the scapula. This muscles job is external rotation, which means that it works to rotate your arm outwards.

The next letter is T, which stands for teres minor. This is an in itty-bitty muscle that actually is located directly below the infraspinatus, and it also helps to rotate the arm outwards, although it is a relatively weak muscle and really doesn’t do that much (hence, why it is referred to as minor).

The last letter is S, which stands for subscapularis. This muscle is actually located directly in front of the scapula, and actually does internal rotation, which means that it rotates the arm inwards.

So overall, to summarize, the rotator cuff is a set of small muscles and tendons in the deep shoulder, which serve to hold the upper arm in its socket, and also help with the vital motions of:

Abduction

External rotation

Internal rotation

And as you can see, though these muscles are quite small, they are extremely important.

Now, let’s talk about how this thing can potentially get injured. Rotator cuff tears are unfortunately very common, especially among athletes and people who do a lot of manual work. Let’s take a deep dive and look at how this actually happens.

When we’re talking about rotator cuff tears, the most commonly involved structure is the supraspinatus, though the other muscles can also sometimes be involved also.

As we said earlier, the supraspinatus is the muscle and tendon that abducts the shoulder, and also passes under this bony shield known as the acromion.

Now, as you can probably tell from the diagram, this puts the supraspinatus in a rather vulnerable position, as it can often rub and bump up against the acromion when you do lots of overhead activities, or lots of repeated active shoulder abduction motions. Also, there is a subset of patients who have something called a hooked acromion, which means that their acromion actually has a hook-like shape, and will thus cause a lot more rubbing and friction against the rotator cuff, and increases their likelihood of sustaining injury.

Most rotator cuff tears occur as a result of excessive overuse, such as if your job involves manual labor, or perhaps you have been training in boxing or MMA, or even just playing a lot of tennis. It also can occur suddenly, as often seen with baseball pitchers.

Now, interestingly, a lot of people actually have asymptomatic tears of their rotator cuff tendons. I remember during my residency, we would often practice diagnostic ultrasound on each other, and it was quite common to find rotator cuff tears in our co-residents that they didn’t even know they had.

Now of course, if you’re watching this video you probably have significant pain, which means that your rotator cuff is likely both torn and also actively inflamed.

Now, a very common question patients ask is if they need surgery for this.

And the answer, much to their relief, is usually no.

In fact, over 80 percent of rotator cuff tears can be managed conservatively, without surgery and recover very well with just conservative management, and this even includes many patients who have full-thickness tears.

In general, surgery is reserved for those who have failed all of the standard conservative treatments first, and even then it is wise to have an in-depth discussion with your physician before moving forward.

Now, the topic of conservative treatments for the rotator cuff is really quite huge, so I’m going to give a succinct overview here, and hopefully do some additional videos focusing on this topic specifically.

Now, the rehabilitation of a rotator cuff tear can be broken into 4 distinct steps or phases.

1) The first step is to control the pain. This is because rotator cuff tears can be really quite painful and debilitating, so the first step is to control that pain so that you can engage in your physical therapy properly, and also allow you to sleep and just go about living your life.

As far as pain control goes, the simplest and easiest first thing to do is to apply ice, which will help to ease the inflammation and swelling. In general, you want to ice for about 15-20 minutes at a time.

If you don’t have liver problems, you can also take Tylenol, following the directions on the bottle.

You can also try NSAIDs, which are non-steroidal anti-inflammatory drugs. Examples of these would be naproxen or ibuprofen, and these types of medications are a very good short-term choice if you don’t have stomach or kidney problems.

However, because they can potentially cause stomach and kidney problems when taken in the long-term, you really want to talk to your doctor if you plan on taking them for more than one or two weeks. Also, while most of these NSAIDs are over-the-counter, there are a few good ones that are prescription only. I personally like prescribing meloxicam, and also celebrex if insurance covers it, because both are more selective inhibitors of cyclooxygenase, which essentially means that they tend to cause less GI and kidney side effects. Of course, if you find yourself needing to take NSAIDs for longer than a week you can definitely talk to your doctor about the various options that might be right for you.

Lastly, you can also try a steroid injection into the shoulder. Since I was trained in Interventional Pain Medicine and PM&R, I have done tons of these and I really like doing them. It is a very simple injection, and can be easily performed by pain medicine, PM&R, sports medicine, or orthopedic doctors, and also by many general practitioners.

Most doctors do these injections using only anatomical landmarks, and this is super quick and easy; after sterilizing the region your doctor will just shoot a little mixture of steroid medication and local anesthetic under the acromion and over the rotator cuff, thus bathing the entire area in anti-inflammatory medication.

You can also do the same procedure using ultrasound guidance; this increases the accuracy and will also give you a little more peace of mind that the medication got directly to the target. I’ve done many hundreds of these using both of these methods and I think that both work very well, though to be honest, I actually prefer the landmark method because it is so quick and easy for the patient. Of course, depending on your past medical history, you may or may not be eligible to safely receive a steroid injection, so if you’re interested, definitely talk to your doctor about whether you’d be a good candidate for the procedure.

2) The next step is to rebuild your range of motion. Oftentimes, after a rotator cuff tear, people go through a period of time in which their shoulder is relatively immobile due to the pain, and so over time they come to find that they’ve lost a lot of range of motion.

Thus, the next step is to work with a physical or occupational therapist to slowly rebuild the range of motion of your shoulder. This usually starts with passive range of motion, and gradually progresses to active range of motion.

Now, it is important to keep in mind that the home exercises that your physical therapist gives you are just as important, if not important, as the exercises you do during the actual therapy sessions.

3) The next step is to progressively strengthen the shoulder. This involves strengthening the deltoid muscle, as well as strengthening the rotator cuff itself. It also involves strengthening the muscle groups around the shoulder to help to stabilize it and thus rebuild a strong foundation, so to speak, and this is known as scapular stabilization.

4) The last step is to continue strengthening the shoulder while gradually returning to the activities you love doing. This phase involves additional strengthening exercises as well as activity-specific exercises.

Now, it’s important to make sure that you have patience throughout these steps. In severe rotator cuff tears it is actually quite common for it to require 12 weeks or more to progress through all of these steps, though it could definitely progress more quickly than that also.

So there you have it, an overview of your rotator cuff and all of the essential information you need to know. I’m Dr. Chu with 360 Pain Academy; thanks for watching, and make sure to check out the website for lots of free articles about overcoming pain. Take care until the next video.

References:

American Academy of Orthopaedic Surgeons. Management of Rotator Cuff Injuries Clinical Practice Guideline. Published March 11, 2019

Braddom, R. L. (Ed.). (2010). Physical medicine and rehabilitation (4th ed.). Saunders/Elsevier.

Cuccurullo, S. J. (2004). Physical medicine and rehabilitation board review. Demos Medical Publishing.

Massachusetts General Brigham Sports Medicine. Rehabilitation Protocol for Non-Operative Massive Rotator Cuff Tear(s).