Shoulder Replacement Explained in Simple Terms

I'm Dr. Patrick Denard, a shoulder specialist at the Oregon Shoulder Institute. I do 100% shoulder surgery, and this video is intended to really help my patients who are going through shoulder replacement to kind of understand the process, what it looks like, what the risks are, and everything from beginning to afterwards. They really have a better understanding. My goal as a shoulder specialist is that my patients really feel informed about their process. I think that, that process when somebody really knows what's going on helps them have a better outcome and improves communication. So we're going to go over some of, some of the high-level things about shoulder replacement. So first off, it's always important to consider the shoulder anatomy. When we're talking about shoulder replacement, you really need to think about arthritis and you need to think about the rotator cuff. So what is the rotator cuff? It's not the cup, it's the rotator cuff. There are 4 muscles that surround the ball and socket joint. And these muscles really help not only drive function of the shoulder but also provide stability to the shoulder. And that is really, really important because the shoulder is the most mobile joint in the body. But because it's very mobile, it's susceptible to instability either before in the form of tears or after if the rotator cuff does not heal depending on the type of repair or replacement that is being done. When it comes to the bone, We talk about arthritis in a lot of different locations. You know, it's really common for people to have an MRI that says there's AC joint arthritis, but that's really not what we're concerned about. We're concerned about the glenohumeral joint, the ball and socket joint, and that is where the arthritis and a shoulder replacement is addressed. And that's really what drives the mobility or function of the shoulder more than any other part of it. Now, with shoulder arthritis, what happens is that normal cartilage layer between the ball and the socket. There's cartilage on both sides, wears down. That leads to lack of motion. It often leads to mechanical symptoms and pain, of course, as a result. Sometimes you can get bone spurs as a result of that. You can get cystic change in the bone, which is a reaction of the bone to arthritis. Essentially, you wanna think about this as the padding in the joint wearing down. And this typically occurs with time. Although in some cases it can occur after injury. And there's a strong genetic relationship as well. So it's not uncommon for people to come to me who are having a shoulder replacement and they've had other replacements in other joints of their body such as their hip or their knee. There's really two broad categories of shoulder arthritis. There's multiple categories, but there's two broad categories. The first is primary glenohumeral arthritis. In this case, the rotator cuff is intact. And you have loss of cartilage and you get bone spur formation. So an example here on the left side, we see a normal x-ray. You can see a clear space between the ball and the socket joint. This is looking straight at, uh, somebody with this x-ray. And on the right side, you see somebody who has large bone spur, what some people even term a goat's beard. There's loss of that normal clear space because the cartilage is worn away because x-ray goes through cartilage. Now, the other broad category is rotator cuff arthropathy or rotator cuff arthritis. This occurs where, again, on the left side we have a normal joint. On the right side, if the rotator cuff is compromised, you have lack of stability. We talked about that earlier. The ball rides up as a result because you get what's called loss of concavity compression because the rotator cuff normally pulls the ball into the socket. Provides that stability. So the ball rides up, you get abnormal mechanics, and over time those abnormal mechanics lead to arthritis of the shoulder joint. So what is a shoulder replacement? Really, at a high level here, what we're trying to do is remove arthritis and improve pain and improve function. There are two broad categories: anatomic shoulder replacement and reverse shoulder replacement. In an anatomic shoulder replacement, it relies on the rotator cuff being intact or functional. That's because the stability is provided by the rotator cuff. Simply understood, what we try to do is restore the anatomy. So we replace the ball with a metal ball and the socket with a plastic socket. That's sort of the cartilage padding. And we want to do that in a way that it respects the normal anatomy of the patient. With reverse shoulder replacement, what we're doing is we're typically using this in people with a lot of bone loss on the socket side. Or in people who have rotator cuff tears where there's not stability. So in this case, a ball is placed on the socket side and the stem of the cup is placed on the arm bone side. Both accomplish getting rid of arthritis. They just work through different mechanisms. So I want to show you a video here which really kind of walks through, uh, anatomic shoulder replacement, and I'll show one with reverse shoulder replacement. This is a pretty good video. It's a little bit different than what I do, but I think animations are really helpful in in the understanding. Again, here we've talked about the ball and the socket joint where we have a normal shoulder joint, the glenohumeral joint being really the major site of function or motion of the shoulder itself. And of course, when you have damage to the cartilage, you get again loss of joint space that leads to pain and decreased range of motion. So what we do with an anatomic shoulder replacement is remove that diseased cartilage on the ball side. And then on the socket side, we also remove that diseased cartilage and we place in a plastic socket. That's the most common method at this point in time in 2026 as of this video, although there are evolving techniques for that as well. And on the ball side, there are really two options. You can place a stem and place a ball on top of that. What I do in my cases is actually use what's called a stemless device because that leads to less violation of the bone and better restoration of the anatomy. A stem is really only used in people with very poor bone quality, and I would actually argue in those cases probably there's other things going on to the point where reverse shoulder replacement should be considered. But I think the, the big thing to point out here is that in most cases, in order to get into the shoulder, you have to take down one tendon in the front of the shoulder called the subscapularis. And that subscapularis, as you can see pictured here, must be repaired at the time, and that needs to heal to get function of the shoulder, or at least function is better when that tendon heals. Now, there are some approaches using what's called subscapularis sparing approaches where the subscapularis is not taken down. However, overall, the literature currently looking at that technique shows that while it's appealing because you don't have necessarily to have healing of that tendon and perhaps a faster rehab, there are many limitations, particularly in the sizing of the implants. And what's critical is that placement of the components is anatomic. So getting those off, if you're even off by a few millimeters, really affects function long term. So the gold standard right now is to take down the subscapularis by various amounts approaches. What I do is take off a fleck of bone because bone heals the best, and then repair that back at the end. And that also drives some of the rehab afterwards that we'll get into. Now with the reverse shoulder replacement, uh, it's a little bit different here. So instead of restoring the anatomy in the goal of trying to make it like it was before somebody had arthritis, what we're doing is putting a ball on the socket side and a stem with a cup on the arm bone side. So again, here, diseased cartilage, limiting range of motion, causing pain. The ball again is removed as it is done for an anatomic replacement. I remove that at the exact same angle or position. And then when we go to the socket side, what we do is we prep a base plate. That base plate is prepped so it can hold what's called a glenosphere. That glenosphere is the ball. And that's really gonna be fixed in place by fixing that glenosphere in place. What you do is you have stability restored because the cup is on the arm bone side. So a lot of people think reverse shoulder replacement is somehow changing the arm substantially. It's really not. It's just reversing the ball socket relationship to provide stability of the joint. Now again, this is very effective in people who have rotator cuff tears. Or in people who have problems on the socket side where there's not a lot of bone. And that's because when you're fixing the base plate on the socket side, there are screws that go into the bone and, uh, typically a post that really provide enhanced biomechanical fixation. Because of the change in relationship of the ball and socket joint, there are some limitations. So for instance, Reverse shoulder replacement is very good for getting somebody to raise their arm overhead and go out to the side. However, people can be more limited behind the back, and that has to do with the anatomy of the shoulder joint itself. So because a normal shoulder not only rotates but it glides, with a reverse replacement this is not happening because you can't glide around that ball. You can only move around that fixed point. You can be more limited in internal rotation behind the back, especially how the shoulder is designed with some bones in front of the shoulder that can limit internal rotation. We take several steps, or I take several steps, to try to improve that. One is moving patients early. Two is in both anatomic and reverse shoulder replacement situations, I plan in advance. In particular, we really want to pay attention to the size of that ball because our data shows that actually having a smaller ball or the smallest possible ball for the individual patient with lateralization, meaning going away from the socket side, improves range of motion, particularly motion behind the back. It also actually limits pain compared to if you have really large spheres or glenospheres. Those can create more overstuffing. Now, when you look at preparing for this, I really think about surgery not starting at the day of surgery but beginning months in advance. So one of the biggest things, or one of the, the key factors that people can really pull on as a lever to improve their chances of a good outcome, is nutrition. A lot of people think that they eat well, but the reality is your body needs more fuel after a shoulder replacement, or any surgery for that matter. So it's really important to increase your protein. There's also data showing that certain vitamins increases your chances of a good outcome. I in particular recommend the THRIVE Protocol, which is in all the information, my packets. But even if somebody doesn't want to do that, I would really encourage them to do something on their own. And it's not just eating well, it's supplementing in addition. I obtain vitamin D levels on all my patients as well prior to, because the impact vitamin D on surgical outcomes is well documented prior to the surgery. I not only recommend that everybody read the surgical packet that I provide, which is over 20 pages, but they have a preoperative visit. That's just a chance to go over final questions, to really understand the procedure. If there's any details that somebody doesn't understand, make sure that everybody is aligned. One of the other key things is really limiting the chance of infection. So infection in the shoulder is a little bit different than infection in knee or hip. It's caused by bacteria most commonly that live in the skin in the front of the shoulder called C. acnes. One of the simplest things that anybody can do to lower their risk of infection is to use benzoyl peroxide, also called Clearasil. This is an over-the-counter medication that actually kills the bacteria that lives in the skin. Now, it's commonly used for acne, and that's because this same bacteria is associated with acne. But again, because it lives in front of the shoulder, if you put this cream over several days in advance, this reduces the bacterial burden, and we think it lowers the risk of infection. The night prior to surgery, you want to not eat or drink anything. However, I would recommend carbohydrate loading the night prior to surgery. I typically recommend that with a high carbohydrate drink that's included in the Thrive Protocol. If somebody does not do that, I would recommend that they consume a high carbohydrate drink the night prior. And that's because when you don't eat or drink anything after midnight, because of anesthesia requirements, they're worried about things like aspiration. They want your They want your belly to basically be free of food. The downside of that is that you can go into depletion and your body needs that energy to go through surgery. It's the same thing we talked about having the fuel in general. So having that carbohydrate loading in advance, just like an athlete prepares for an event, will help you get through surgery. And the, the data clearly supports that concept. The day of surgery, you want to check your arrival time, but typically you're going to arrive anywhere from an hour and a half to 2 hours in advance. This is an outpatient procedure, so 90% of the shoulder replacements I perform, patients go home the same day. The majority of those are done in an ambulatory surgery center, and that really allows people to recover in the safety of their own home and have a lower complication rate in general. Typically, people are going to take their normal medications. The one exception to that is— there's actually two exceptions to that, but the major one is lisinopril. You don't want to take that the morning of surgery because if somebody is on lisinopril and they take that, that can drop their blood pressure. The other thing that people will need to stop prior to surgery is blood thinners. That's always going to be discussed in advance and it varies by the type of blood thinner somebody takes, which we can have a personalized discussion about and go through that. Now what are the risks and complications? Anytime you're having surgery, shoulder surgery or any type of surgery, there are risk of complications. The general complications are those you have with any surgery. There's infection, blood clots, bleeding, nerve injury. Infection rate for shoulder replacement in the literature, meaning published studies, it's about 2 to 4%. My infection rate is less than 1%. That has to do with several things. Number one is doing things like the benzoyl peroxide in advance. Number two is we really try to optimize nutrition. Number three, I have an extensive protocol to reduce that risk that includes preoperative antibiotics and how we prep the skin, etc., as we go through, and things we do during the time of surgery to reduce that chance of infection. Um, and lastly is surgical speed. So it's well shown that the longer a surgery takes, the more inflammation is created, the more the risk of infection goes up. Because this is all I do, we have a shorter surgical time, which leads to less risk of infection afterwards. Blood clots, I typically recommend that somebody take a baby aspirin for a couple of weeks afterwards. The risk of blood clot for shoulder replacement is very, very low. I perhaps see one of these every couple of years, and it's usually in somebody who has a history of blood clots. If somebody does have a history of blood clots, I recommend that we do something beyond aspirin going in to reduce that risk. Bleeding or hematoma, I've never had to give somebody a blood transfusion for a primary shoulder replacement. It's even very rare with a revision shoulder replacement. It can occur that people can get a hematoma, which is essentially some bleeding inside the shoulder that leads to swelling. This risk is very low. It's gotten really, really low, in particular in the last several years, because we give a medication called tranexamic acid, and that really lowers the risk of bleeding during surgery. Nerve injury, also very uncommon. We'll talk about the risk with nerve blocks subsequently, but essentially because you're working around the shoulder, there's always risk of stretching nerves. That risk is very low if you know the anatomy and know exactly what you're doing in these cases. Specifically when we talk about anatomic shoulder replacement, there's some specific risks that I think are important to be aware of. The big one is rotator cuff healing failure. Meaning that you take down the subscapularis tendon and that tendon does not heal. If that does not occur, sometimes you'll see people end up with instability of their shoulder. Also, long-term, there's the concern that the rotator cuff degenerates over time and leads to instability. This is the most common early complication of a shoulder replacement, especially an anatomic shoulder replacement. If that occurs, it can be managed. Oftentimes it can be managed with a conservative approach. In some cases, somebody can require conversion to a reverse shoulder replacement. Long term, the survival of a shoulder implant is 90% at 10 years, 70 to 80% at 20 years. What do I mean by that? That means that if you look 10 years later, 90% of the implants are still in somebody's shoulder, and 20 years later, 70 to 80% are still in somebody's shoulder. The more you use it, the more that plastic socket can wear out. But if you look at the overall track record, it's very good. So for somebody who's very young, say under the age of 55, there's some specific considerations that we may alter technique, et cetera, to try to lower this risk. We always try to lower the risk in general, but there's some specific considerations in those people who are very, very active. We talked about rotator cuff failure long-term already. In terms of reverse shoulder replacement, the unique risks to reverse shoulder replacement compared to anatomic replacement are a couple-fold. The survival of the implant is very, very similar. 90% at 10 years, 70 to 80% at 20 years. So the track record is very good. But there's a couple of unique risk factors. Number one is dislocation. That means because you have a joint that's constrained around that ball, that shoulder dislocates. Again, In the literature studies, this rate is about 3 to 4%. My personal rate is less than 1%, and that's because I have a very specific protocol for patients based on their preoperative plan. I look at their CT scans and their MRIs and use an approach for restoring soft tissue stability based on that plan with what their status of their soft tissue looks like, as well as their height. And that allows me to restore stability to the joint and have a very low risk of dislocation. The one complication that's very hard to reduce the risk of is acromial stress fracture. Now, because you have a ball on the socket side and the stem of the cup on the arm bone side, effectively the arm is lengthened a bit. That puts tension on the acromion bone. Just like a runner can go out and say they start running miles and miles, they can get a stress reaction which can turn into a stress fracture. That can occur with reverse shoulder replacement because we're putting the arm in a new position. Now that rate in the literature is about 4%. Our rate is right there at that number. We take some steps to try to prevent this. Number one is looking at factors going in like vitamin D levels and bone density, especially in older people. The risk increases as people age or get older because bone density declines. If we identify this, we can treat this in advance. So that's why it's really important to take a look at those factors. A second thing that's really important is nutrition. I spoke about that earlier. Our data, my data in particular, shows that people who are nutritionally deficient have a higher risk of this occurring. So we try to lower this risk by encouraging high protein prior to surgery and immediately after surgery. Another thing that's not proven but I think provides a benefit is early range of motion, and I encourage early isometrics prior to surgery. This is on my rehab site where you can see these exercises in advance, but the idea here is that bone remodels in response to stress. So if you start engaging the arm early, that can provide some benefit by getting the bone to remodel, to sort of prep in advance. And that's important because a lot of people who need a reverse shoulder replacement, they haven't been able to use their arm a lot. So you sort of get what's called disuse osteopenia, meaning because there's not a lot of activity, bone density declines. And again, bone remodels in response to stress. So even if somebody can't use arm, if we can get them against a wall, isometrics, I think that provides benefit. Another thing with reverse shoulder replacement is I don't like having people in a sling for a long period of time because if they just rest for 4 weeks, that disuse osteopenia can actually progress. So I like them to do some controlled early motion right after surgery and come out of the sling at 2 weeks. Now the caveat there is I don't want it to be aggressive. So we want some early motion to ease people into this process. But there's actually data showing that if somebody goes to formal physical therapy too early, like right out of the gate, they actually increase this risk of stress fractures. So it has to be done in a controlled, thoughtful manner. Long term, the risk really is that people do not do as well with internal rotation behind the back. I spoke about that earlier. That's really the limitation compared to anatomic shoulder replacement. And When you look at the best outcomes, the best range of motion, it's better with an anatomic compared to reverse shoulder replacement. Both people will get above their head or above their shoulder level, that is, and out to the side. But you'll get slightly better range of motion with an anatomic. And in particular, that occurs with internal rotation behind the back. Long-term risk, component loosening, it's really rare. Usually what happens is the plastic liner wears out. That plastic liner wearing out leads to what's called loss of containment. That loss of containment, because you get asymmetric wear— that is, wear on the bottom of the plastic in particular— can lead to instability. That typically will occur many, many years after the procedure, say 10 years. If that occurs, that is manageable because you can simply exchange that plastic liner and perhaps change the size of the ball to improve stability. Now, of course, anytime somebody is having surgery, it's important to recognize that there are alternatives. You can do things like medications, like anti-inflammatories in particular. Injections are an option, whether that's steroid or PRP. And then of course, physical therapy. Physical therapy is typically effective for mild to moderate arthritis. It is not typically effective for severe arthritis where somebody has bone-on-bone arthritis and very limited range of motion. But these are alternatives and we always try to maximize these first. What happens after rehabilitation? Everybody's worried about the time being in the sling. This varies a little bit for me based on the procedure that we do. For an anatomic replacement, I have somebody in a sling for 4 weeks. During that time, they're doing hand, wrist, and elbow range of motion only. They start formal therapy at 4 weeks and work their way up. The reason I don't do a lot of immediate range of motion for an anatomic replacement is because that subscapularis healing in the front of the shoulder is so critical. We did a randomized controlled trial several years ago showing that if people sat in the sling for 4 weeks with an anatomic replacement, they had higher healing rates and they actually did better long term. They had a little bit slower recovery like the first few weeks, but it resolved by 8 to 12 weeks and again, better long term. So that trade-off is worth it. And it's there. With a reverse shoulder replacement, because you're not reliant on the subscapularis for healing, although we do repair it after the procedure, I let somebody come out of sling in 2 weeks and I'll let them do some immediate range of motion for the reasons I expressed earlier, and that has to do with not getting disuse osteopenia. However, I typically don't start formal physical therapy again to the 4 weeks for the same point of not overdoing it at the beginning. There are some cases, especially with reverse replacement, where I'll do what's called a subscapularis sparing approach. I mentioned that with anatomic. With anatomic, there are limitations because of bone spurs, etc., that can make that have some downsides with position that are not there with component position of reverse. So in certain settings, I'll do a subscapularis sparing, and in those cases, it's a sling for comfort only, but it's a case-by-case basis. The sling typically has a pillow or a brace where you're out to the side, uh, to really provide some support early on. Afterwards, what does it look like for pain management? A lot of people think that shoulder replacement is going to be a very painful procedure. It turns out the recovery from shoulder replacement in my patients is actually easier than rotator cuff. 30% of my patients do not take a single narcotic. How do we do this? We use a multimodal approach. So we use medications that are non-narcotic like Tylenol, ibuprofen, a nerve pain medication at night. We do provide a few narcotic medications, but it's very rare for any of my patients to get a refill on those. So we only provide 10 to 15 pills, and that's very effective. It's also really key to use ice. It sounds basic, but having ice with a cold compression unit has been shown to improve outcomes, lower pain scores after procedure. And if you combine all these things with an efficient procedure that doesn't have your inflammation levels spike a lot, you can really get through this in an effective manner. Of course, removing the arthritis itself really does a lot as well. At the time of surgery, part of the multimodal approach is either having a nerve block or local anesthesia, and it's really the patient's choice of what they want to do in this regard. So with a nerve block, you have a needle placed around the brachial plexus, which are the bundle of nerves that go down your arm. That provides anesthetic at that site that will numb up the arm for 12 to 18 hours. That provides complete pain relief. There are some downsides. There's a small risk of permanent nerve injury anytime you're putting a needle around nerves. Now that risk is less than 1%, but if you look closely at the studies, you'll see that many patients, or a few percent of patients, have some numbness that persists for a couple of months. That typically resolves over time. The other thing with a nerve block is that some people don't like the feeling of having lack of control over the arm because you're numbing up the entire set of nerves. You can get both sensory and motor control loss. And some people really don't like having the arm feel like it's sort of flaccid or can't move for that 12 to 18 hours. With a local anesthetic, what I do is I just inject local medication around the shoulder itself, including some of the major nerves that go to the shoulder but not in the neck, and provide that in the skin and soft tissue. That does not provide as complete a pain relief immediately. Typically somebody after this is going to say have a 3 or 4 out of 10 pain compared to 0 out of 10 with a nerve block. When you look at the two at 24 hours, however, there is no difference between the two because once you get through that early period, there's really no difference. The upside to the local anesthesia— that means injecting nerve medication or numbing medication around the shoulder— is that you essentially have no risk of nerve injury. So how do you decide? I would say most people decide to have a nerve block because the risk of complication is overall very low. Again, serious nerve injury less than 1%, a couple of percent of people having some numbness persists. I think it's also very beneficial if somebody is traveling the day of surgery, say they're going a couple of hours or many hours away, it's probably better to have complete nerve medication or nerve block to really have complete numbness. If you're somebody who is very stoic and you feel that you really have a high pain tolerance and you're in the local area, doing a local anesthetic is probably sufficient. What does the recovery look like? This looks at my patients. This is an ASCS score, American Shoulder and Elbow Surgeons score. It's a validated score that we administer and use for publication as well. The point here that I really want to show you is that much of the recovery after shoulder replacement occurs in the first 3 months. And in fact, by 6 months and you go beyond, it's really pretty flat, meaning that 80% of the recovery occurs in the first, uh, 6 months— or sorry, 3 months— and by 6 months it's pretty flat. So you'll get some small gains perhaps between 6 months and 1 year that are not detected by this scoring system, but much of the gain occurs really early. So I typically tell somebody 6 months for full recovery, and at 3 months you're about 80% of the recovery. In terms of pain, you see the pain scores drop off right away, really within 2 weeks. Most of my patients come back and say they have pain score of anywhere from 0 to 2. They're not typically taking narcotic medication at that point in time, and that really levels off very, very quickly. What does self-care at home look like? First off, I really advise that people keep moving right away. Walking right away is highly encouraged. You should be doing that because it helps your body recover in general. Actually, there's even studies that say if walk, you have lower shoulder pain, you can do some early range of motion that's based on your particular rehab protocol. When you are sitting on the couch and you're awake, you can rest with your sling off, sort of replicating the position. I actually like that because not having that pillow or brace on the inside, sometimes that'll push on the inside and cause a little swelling. So getting a break from that is really important. But if you're up moving around, you're walking, you're sleeping, the sling is on. Sleeping with the sling on can be difficult. One alternative to that is to use what's called a shoulder sleeper pillow. Some people find that very comfortable. That's something that can be obtained online. We have a referral code for anybody who wants to get that. Additionally, sleeping— I like to use a wedge pillow that goes in my bed. I actually had shoulder surgery myself. That helps you sleep a little bit upright to take a little bit of pressure off the shoulder. I like using the ice compression machine at night to help sleep as well. After shoulder replacement, you can shower 48 hours afterwards. You're doing hand, wrist, and elbow stuff right away, so you're able to do self-care, eating, typing, those types of things. The other big one is driving. People ask about driving all the time. It's— there are studies showing you can drive at 2 weeks safely with a sling on. What does return to activity look like? Again, you're moving right away. Really, over the first couple of weeks, you're working on the pain stuff, early range of motion. Your rehab is based on your protocol. Then at the couple of weeks standpoint to a couple of months standpoint, you're going back into therapy, you're gradually advancing your activities, and our goal is full activity at 4 to 6 months without restrictions. So for instance, golf is one that people ask about a lot. I typically allow putting at 3 months, chipping at 4 months, full swing at the 5 to 6 month point. That can be accelerated in some cases, but that's a general guideline. So I hope that this helps you understand shoulder replacement better. Again, being more informed is going to help you get through the process in the best possible way. Our goal is to be there for you every step of the way. If you have questions, please reach out anytime, and we would love to answer those for you to get you the best outcome and information possible. Thank you.