Artificial Replacement of the Shoulder - Prof. W. Angus Wallace

Dr. Sechrest: Hello, I’m Dr. Randale Sechrest, your host for eOrthopod.TV. Today I have as a guest, Professor Angus Wallace, from the University of Nottingham. Today we’ll be talking about shoulder arthroplasty. Good afternoon, Dr. Wallace.

Dr. Wallace: Good afternoon, Dr. Sechrest.

Dr. Sechrest: Professor Wallace, what I thought we would talk about today is a procedure, that I understand you’re an expert on, called shoulder arthroplasty, and for patients that are watching, shoulder arthroplasty refers to artificial replacement of the shoulder. So what I thought we would talk about first is a little bit about the procedure and the conditions that the procedure is used for. Why would a patient come to you for a shoulder arthroplasty? What disease processes lead a patient to need a shoulder arthroplasty?

Dr. Wallace: The usual disease is osteoarthritis of the shoulder, sometimes called OA for short, and this is a condition of wear and tear of the joint inside the joint. Your shoulder is normally covered inside with what we call cartilage, and that is a nice, smooth, slidey surface, and that cartilage in osteoarthritis disappears and you start to get bone on bone contact and that is painful and actually makes noise. So some people get shoulders that creak.

Dr. Sechrest: So osteoarthritis or wear and tear arthritis is the most common cause for a shoulder arthroplasty. Do you ever have to perform shoulder arthroplasties for other disease processes such as fractures of the shoulder or problems with other types of arthritis like rheumatoid arthritis?

Dr. Wallace: Yes, rheumatoid arthritis used to be one of the common indications in the United Kingdom, but modern drugs have made the need for a shoulder replacement very much less, so we don’t see so many rheumatoid patients now. We do treat quite a lot of fractures with shoulder replacements, and the shoulder replacement is usually just the hemi-arthroplasty – that’s half the joint – we replace the ball of the joint and use the stem of the artificial joint to help splint the fracture.

Dr. Sechrest: Let’s move on a little bit and talk a bit about the area of the body that we’re really talking about and some of the anatomy of the shoulder. Can you describe, when we’re talking about the shoulder joint, what parts of the body are we talking about?

Dr. Wallace: Well, we’re looking at the whole of the shoulder area, but the shoulder comprises four different joints. You’ve got the ball and socket joint inside the shoulder, which is the one that we are talking about replacing. You’ve also got a joint up above the shoulder between the collar bone and the point of the shoulder that we call acromioclavicular joint. Then we’ve got, at the inner side, a joint where the collar bone articulates with the breast bone, and then underneath the shoulder blade there is a joint between the shoulder blade and the chest and that’s actually quite an important joint. That’s a sliding joint where the shoulder blade slides over the chest wall. Many people don’t appreciate that when you move your shoulder one-third of the movement is actually shoulder blade movement and not shoulder joint movement. Two-thirds is shoulder joint movement. So the combination, when you lift your arm up is usually one-third shoulder blade on the chest wall, and two-thirds movement at the true shoulder joint.

Dr. Sechrest: Now if I’m a patient and I’m developing osteoarthritis or any type of arthritis of the shoulder that may need an artificial joint replacement of the shoulder, what sort of symptoms am I looking for? What sort of symptoms bring patients into your office?

Dr. Wallace: Patients start to get pain in the region of the upper arm and they get confused because the pain is felt in this area here below the shoulder rather than in the true shoulder itself. This is what we call ‘referred’ pain so the pain is being felt in a different place from where the problem is, and the arthritis inside the joint gives pain initially in the upper arm and then, as the arthritis becomes more severe, it moves down the arm into the forearm, and this can be very confusing for patients who can’t understand why they’ve got arm pain when actually it’s a shoulder problem. The other thing that alerts them to the fact that this is getting worse is that they start to get night pain and their sleep is disturbed at night. But if they lie perfectly still they can usually avoid having too much discomfort.

Dr. Sechrest: Now let’s talk a little bit about treatment other than surgery. When you are treating patients who have osteoarthritis of the shoulder or one of these other arthritis problems, mostly wear and tear arthritis of the shoulder, what sort of treatments are you going to recommend prior to surgery, before you consider going ahead and doing a shoulder replacement.

Dr. Wallace: Initially, we recommend the non-steroidal anti-inflammatory drugs. The sort of drugs that we use are ibuprofen, which you take orally, and that reduces the inflammation and the pain a little. We don’t however like patients to be forced into taking these drugs long-term, because they do occasionally upset the stomach and you’ve got to be careful of that. We modify their activities and if, for instance, your shoulder is getting painful initially from a sporting activity – playing tennis or doing lifting above shoulder level – then we may simply modify activities in order to make the patient more comfortable. However, as the condition progresses this limitation becomes intrusive and once you get to the stage of having night pain, that’s the time when you really have to start thinking about whether you need a shoulder replacement operation.

Dr. Sechrest: Now, do you rely on any sort of injections? Are you a believer in cortisone injections for this disease process? Physical therapy as a treatment for osteoarthritis of the shoulder? Do you feel like that’s been official at all?

Dr. Wallace: I do try physiotherapy. Sometimes patients develop a degree of shoulder stiffness with their osteoarthritis and if you can stretch it out, they improve significantly. I also do use steroid injections into shoulder, but my experience has been that if you inject the shoulder with steroids you get good pain relief for about 6-8 weeks, but then the pain comes back again and sometimes it can come back worse than it was before you injected the shoulder so it’s not a way of solving the problem.

Dr. Sechrest: When you sit down and have a discussion with a patient who’s trying to decide whether it’s time to consider an artificial shoulder replacement, what are the keys that you use to determine whether or not to recommend surgery for that patient?

Dr. Wallace: I think it’s important for me to understand and get to know the patient quite well. I need to know what activities the patient does; what they get up to at home; I need to know whether their medical conditions, if they have any, are serious. One of my reasons for not offering a shoulder replacement in some patients is if they are falling regularly. As you can appreciate as you get older you tend to fall a little bit, but if you are falling once or twice or week then if we were to do a shoulder replacement, there is a risk of a nasty fracture occurring in the region of the shoulder replacement and that can be difficult to manage. However, if you focus with the patient on what they want out of their life, if the arthritis is intrusive, if it’s stopping them doing things they want to do, then that is the time to consider doing a shoulder replacement. The shoulder is a little different from the knee and the hip. If you have arthritis of one knee or one hip, you limp, because you have to use both legs to walk. When you have a painful shoulder you can actually get off by putting your hand in your pocket and using your other arm. So many patients actually put up with their shoulder pain for much longer than they would put up with their hip or knee pain because they just reduce how much they use it. But if, after a period, they can no longer do the things they want to do and that may be household activities, it may be sports, then that is the time for you to discuss with them would they like to consider a shoulder replacement and then explain to them the pros and cons of having that operation.

Dr. Sechrest: Let’s talk a little bit about what you’re trying to achieve as a surgeon. What’s the purpose, what’s the rationale of a shoulder arthroplasty in your mind as a surgeon?

Dr. Wallace: Well, the main indication, Randy, is pain. That is the best indication for doing a shoulder replacement. Treatment of osteoarthritic pain with a shoulder replacement is very effective, and I am quite happy to tell my patients that the chance of giving them pain relief so that they’re content after a shoulder replacement for osteoarthritis is around 90%. The real problem is getting movement back again after a shoulder replacement, and that depends on two things. It depends on how well I do the shoulder replacement, and it depends on how well the patient does their physiotherapy and rehabilitation after the operation. I can do a brilliant operation but if the patient doesn’t do their physiotherapy afterwards, they will end up with a shoulder that doesn’t move so well and they may struggle to get their arm up to and above shoulder level. But if they’re a good patient and they exercise conscientiously after the operation, and later go to the gym, then we can usually get near normal movement back into the shoulder.

Dr. Sechrest: Let’s talk a little bit now about preparation for surgery. Once you and the patient have decided that you’re going to go forward with a shoulder arthroplasty, what do you like to see as a physician for that patient to be evaluated? What sort of things do you request of the patient before you finalize the date for the operation?

Dr. Wallace: Well, we get them to meet physiotherapist well before the operation. They’re given preoperative exercises to try and ensure that they’ve got as much movement as possible from this arthritic shoulder before we take them to the operating room. We explain to them that there is going to be a need to attend physiotherapy sessions and do home exercises and we’ve prepared a brochure that guides them about what is needed.

Dr. Sechrest: Now when you’re doing this preoperative evaluation, do patients need to worry about their medical status? Do you routinely have them meet with an anesthesiologist or their medical physician to get clearance before surgery?

Dr. Wallace: It depends on the patient and their general fitness. As a rough guide, I’m a very simple orthopaedic surgeon. If a patient is on no tablets, no medication, and they can climb a flight of stairs, they’re fit for an operation. But, if they’re on multiple medications, if they’re breathless when they exercise, if they have significant medical problems like diabetes or heart disease then we do get them checked out medically and the anesthesiologist will see them before their operation and check whether they are fit for the operation. One of the things we do see is patients are awful eager to have their operation, and they may get a cold or a bit of flu-like symptoms, and we never operate, on a planned operating list, on a patient who has cold or flu-like symptoms because they can get pneumonia afterwards and we don’t want that to happen. So we put it off for 3-4 weeks to make sure that their ideally fit for the procedure.

Dr. Sechrest: So if a patient is having any sort of problems in terms of infection, sore throat, any skin infections or any problems with respiratory infections such as a cold or perhaps bronchitis, you would opt for allowing them to get over that illness before they went through with an operation.

Dr. Wallace: Very much so. I know that’s frustrating for the patient because they will have made plans for their operation. They may have got family members to take time off but their health is paramount. I think things have changed just a little bit with the use of what we call nerve blocks because we are doing this surgery now with the patients awake. The anesthesiologist will give an injection into the neck and that will freeze and paralyze the whole arm and we are doing joint replacements in that situation. If that is the way we do the joint replacement, the chest is less of a problem because you’re not giving an anesthetic that is inhaled, but it’s still an issue and you really do want to have your patient fighting fit for any operation.

Dr. Sechrest: Well, let’s talk a little bit about the anesthesia and what that means. Do you still you general anesthetic where you put a patient completely to sleep? Or have you gone exclusively to using what you refer to as regional anesthetics where you do a block of sorts that paralyzes and numbs the arm so that you don’t feel the operation but you’re still actually awake?

Dr. Wallace: It’s really half and half in that we, that is the anesthesiologists, discuss with the patient what they want. A lot of patients don’t want to be awake and they would prefer to be asleep for the operation. Some find it quite exciting to be awake for the operation. What I can assure patients is that we only operate when the block, when the nerve block, is completely effective and it is sometimes necessary to convert from a nerve block to giving a general anesthetic if there’s any discomfort. But nowadays our anesthesiologists are very, very good at carrying out these nerve blocks and for us it’s quite interesting because we can chat to the patient during the operation.

Dr. Sechrest: Now, the operation itself. Does a patient come into the hospital the same day of the operation? Is the patient admitted the night before the operation? How is it done in your hospital?

Dr. Wallace: Normally the patient comes in 7 o’clock on the morning of the operation and the operating room list will start at 8:30. We have an all day list. The exception to this is patients who come from a long distance. I provide a regional and a bit of a national joint replacement service in Nottingham and patients travel long distances, up to 5 hours by car to come to the hospital and, in that situation, we have a patient hotel that they stay in overnight prior to the operation and then come down to the operating theatre from the patient hotel for surgery.

Dr. Sechrest: Now, the operation itself, when the patient goes through operation, how long does it normally take, the operation itself?

Dr. Wallace: You’ve got to divide it up to anesthesia time, then the operation proper, and then the recovery time. The anesthesia time, that is putting the block in or giving the general anesthetic or both – probably about half an hour. The operating time, we allow about an hour and a half. The recovery time is about half an hour. So all in all they’re going to be down in the operating room for a period of between 2 ½ - 3 hours.

Dr. Sechrest: And then the patients return to the floor, the ward, so to speak, where they’ll do their recovery for the next several days in the hospital?

Dr. Wallace: That’s right and depending on the fitness of the patient, they may get home after 48 hours. But if they’re elderly, a little bit infirm, they may stay with us for 3 or nowadays a maximum of about 4 days.

Dr. Sechrest: In the postoperative period, what should I expect if I’m a patient afterwards in terms of how much pain should I expect? Am I going to get any sort of IVs or anything else while I’m in the hospital? What goes on immediately after the operation?

Dr. Wallace: You will find that you have an IV, an intravenous infusion, up so that drugs can be given. If you’ve had a block, a nerve block for the operation, you will have absolutely no pain for the first 18 hours. It’s very effective. The problem, and it is a problem, is that block tends to wear off at night often when you’re going to sleep or when you are asleep and then you wake up with some pain so that we encourage our nurses to give medications, pain-killing medication, to the patients 10 o’clock at night before they go to sleep and make sure they have a decent dose of that so that addresses that they will have when the block does wear off. After about 20-24 hours, the pain has subsided significantly and a number of patients tell me, “My pain is gone. I don’t have arthritic pain anymore. I’ve got some bruising, some soreness from the operation.” And the only time they have pain is when the nasty old physiotherapist starts having a go at them and getting them moving and then they do have to work through the discomfort of getting that shoulder moving in the first few days after the operation.

Dr. Sechrest: Now when do you start physical therapy? Is that started on the same day as the operation? The next day? When should I expect a physical therapist to show up in my room?

Dr. Wallace: Well, the physical therapist will have seen the patient before they go down to the operating room. We usually do not start physiotherapy the same day and that is because with the nerve block, the patient can’t do much with their arm and it’s much better that the patient is actually taking part in the physiotherapy exercise. So the following day when the block has worn off from 9 o’clock in the morning, they will start their physiotherapy, and the physiotherapist will take them through the exercises. We do use a broad arm sling, a shoulder immobilizer after the operation but really only for 48 hours until the patient has good control back in their arm, and then, quite honestly, the immobilizer is only used when the patient is out of doors or taking long walks. The rest of the time we prefer to dispense with the immobilizer and get the shoulder going.

Dr. Sechrest: Now I think a lot of patients are sometimes concerned, when they have a major operation like an artificial shoulder replacement, whether or not they’ll need a blood transfusion. Is this a common occurrence when a patient has an artificial shoulder replacement that blood replacement is required, a blood transfusion in the postoperative period?

Dr. Wallace: We no longer use blood transfusion in 99% of our patients. You might have an occasional patient with a bleeding problem. It’s very rare and I can’t remember the last time that I actually transfused a patient for a shoulder replacement operation. It’s a combination of good surgery stopping the bleeding, the use of appropriate drugs to help us control the bleeding, and so blood transfusion is not really necessary. But you do have to, as a surgeon, warn the patient that occasionally something goes wrong. Occasionally you do have a bleeding episode afterwards and therefore perhaps one case in 50 or one case in 100 you might need a blood transfusion but very rarely.

Dr. Sechrest: Well, let’s move on and talk a little bit about how patients recover after a shoulder arthroplasty. I think you mentioned that one is they begin physical therapy fairly quickly. They’ve been given some instructions prior to surgery so they know what they’re going to be expected to do after surgery. They start physical therapy probably while they’re in the hospital and I think what you’ve said is that the patients generally leave anywhere from 48 hours after the procedure to maybe 5 or 6 days after the procedure depending on their general health status and ability to get around. So what happens at that point? How fast am I going to be able to get back to using my shoulder in what I would consider a normal fashion?

Dr. Wallace: Well, I usually tell patients who are working that they should be looking at returning to clerical type work about 4 weeks after the operation. Between discharge from hospital and that 4 weeks, they will do a lot of home exercises. They start off in hospital doing pendulum exercises and what we call pulley exercises and when they go home they are provided with a pulley that clamps over the top of a door and allows them to pull their arm up and down like that on the pulley in order to get the maximum movement out of the shoulder; and actually on the pulley they get all the way up to there using their good arm to pull their bad arm and that’s a very good exercise to get the movement back into the shoulder. Once they get to 4 weeks, we encourage them to go swimming in a warm swimming pool because that is one of the really good ways of getting your maximum movement back again and the physiotherapist is there to ensure that they are doing their home exercises but quite honestly shouldn’t be doing an awful lot of physiotherapy themselves on the patient. It’s the patient doing it for themselves.

Dr. Sechrest: Now let’s talk a little bit about shoulder arthroplasties and the results of shoulder arthroplasty. What has your experience been in terms of the longevity of a shoulder arthroplasty? As I understand it, an artificial shoulder is not a weight-bearing joint such as the hip and the knee so that the wear problems that we have with weight-bearing aren’t quite as much of a problem with the shoulders. How have you seen shoulder arthroplasties function after the surgery is over and after the patient has pretty much healed up from the operation?

Dr. Wallace: Well, the trick is to get good movement early on and, if you get that, you’re on to a winner. The survival is now quite good and I tell my patients that the failure rate from a shoulder replacement, once you’ve got beyond the first 6 months, it’s about 1% a year. That means you get to 10 years and 10% have required a revision operation. As far as the wear is concerned, that depends on how much you do with the shoulder. If you are 70, and I put in a total shoulder replacement, both the ball and the socket, I’m going to expect that to last you your lifetime. But I saw a lady in my clinic yesterday who I put a shoulder replacement in 14 years ago, she’s been very active playing sports, doing all sorts of things, and the socket on the side that was put in 14 years ago has worn and I am going to have to do a revision operation on her. But we’re not seeing a need to do a lot of revision operations. It does seem that these joints are surviving long-term and doing very well.

Dr. Sechrest: What can you expect in terms of range-of-motion after an artificial shoulder replacement and the strength that you have in the arm so that you can use that arm for normal activities? Do you restrict these patients in any way?

Dr. Wallace: I’ve stopped them parachuting, jumping out of a plane, but that’s about as much as I limit their activities. I believe my role as an orthopaedic shoulder surgeon is to give the patient back a shoulder that they can use for the things they want to do. I would emphasize that there is a big difference in the results of movement depending on pathology, that is the disease condition, that the patient has. Osteoarthritis generally results in a very good functioning shoulder and I’d expect to be able to get up to at least 140 degrees, that’s that position, and for some of my patients they are getting full elevation, they’re getting their arm right up in the air. After a shoulder replacement, we aim to try and get as good a shoulder as possible, and you asked me about whether the shoulder is weaker afterwards, and the answer is, “Yes, it is.” In general, patients who have shoulder replacements have lost about 1/3 of the strength in the shoulder compared with a normal shoulder. I’m not sure why that occurs, but we measure the strength in the shoulder using a strength gauge and measuring the pounds you can lift and we typically see the normal shoulder lifting 25 pounds, but the replaced shoulder lifting 12 or 15 pounds in a shoulder that has a good result. So we do see less good strength, but usually the patients don’t recognize that it is weak. The other thing I wanted to mention is sport. Returning to sport after a shoulder replacement is something many people want to do, and personally I like to get them back as soon as it’s safe to do so. People want to go back to play golf. If you’re a good golfer and you don’t hit divots out of the grass, I’m very comfortable with you going back at 3 months. If you’re a bad golfer, back at 4 months. I do return people to playing tennis, playing badminton, these sort of racquet sports. After all, they have had an operation to make their shoulder better. I do that to allow them to return to what they want to do, and sport is something that a lot of people want to do into their 70s and 80s now, and my responsibility as a surgeon is to deliver that service for the patient. But after a fracture, it may not be possible with a shoulder replacement to get back of that sort of condition of racquet sports, but you should be able to get back to golf okay.

Dr. Sechrest: We also talked a little bit about where and how long these prostheses will last a patient. Can you elaborate on that a little bit in terms of how long you feel like a shoulder replacement will last in a typical patient?

Dr. Wallace: It does depend on how active the patient is, but if you’re putting your shoulder replacement into a 70-year-old then they are usually not so active that they’re going to wear that shoulder out. That shoulder is usually going to last the rest of their lives. If, however, you have to put a shoulder replacement into, for instance, a 30-year-old, then you are talking about somebody who is going to be using that shoulder normally for many years and we would be looking at a shoulder that would last perhaps 15-20 years, and we would expect it to undergo significant wear during that period and probably require revision surgery. So I do always tell the younger patients that they should expect to have a revision some time in the future if I put it into somebody between the ages of 30 and 50.

Dr. Sechrest: Professor Wallace, what we should do now is talk about some things that both patients and surgeons sometimes don’t like to hear, and that’s what could go wrong with this operation. Not only during the operation, but perhaps immediately after the operation, and then down the line, years sometimes down the line, what is it that you worry about as an orthopaedic surgeon? So let’s start with first, what are you worried about during the operation that might go wrong?

Dr. Wallace: During the operation it’s very important for me to get the bits of the shoulder replacement in exactly the right place. The ball has to be where the original was. The socket has to be where the original socket was, and that’s actually difficult in some patients who have got a lot of joint damage. But let’s assume we’ve managed to get it into a near perfect position. It’s very important to reconstruct the tendons around the shoulder called the rotator cuff tendons because they are the bits that make the shoulder move afterwards. In rheumatoid patients, the tendons and the muscles are in poor condition, and that is one reason why rheumatoid patients, after shoulder replacement, often don’t get full movement back and often are only able to get up to shoulder level, to about there. You are very dependent on these muscles called the rotator cuff muscles and tendons working effectively after the operation. So I concentrate on getting them right. I then close the wound. We are able to produce very satisfactory cosmetic scars but it is a scar and, for ladies, they are particularly sensitive about the scar and they want it to look as smart as possible, and we tend to use what we call subcuticular so that there’s no suture marks when the stitches come out. The one thing that we really worry about, as surgeons, is getting an infection in that shoulder. We’ve now got the infection rate down to about 1% for an osteoarthritic shoulder. That means 1 person in 100 is going to get an infection, and it doesn’t matter how hard we try, that complication is going to occur; and I warn every patient about this even though it’s a low risk complication because if it happens to that particular patient, then they will have to come back to the operating room for further surgery. They may have to have the joint taken out and revised. But, if we are forced into doing that, we can usually land up at the end of the revision procedure with a shoulder which is still better than the original problem with the shoulder with arthritis.

Dr. Sechrest: Well, that’s good news. What about the risk of bleeding, the risk of damage to the blood vessels, or the nerves around the shoulders? Is this something that is a serious risk or is this something that is very unlikely?

Dr. Wallace: Bleeding, I suppose I see bruising, more bruising than normal, in about 1 patient in 10, but not enough to worry me. It does worry the patients because they see this bruising going down the arm and it’s more painful when you have that bruising. Nerve injury, again, is something that we have to warn the patients about. There are three nerves very close to the shoulder and all three nerves can be injured at a shoulder replacement operation by traction, that is, pulling on the nerves. The nerves which are at risk are the axillary nerve, and that’s a nerve that supplies the deltoid muscle, this muscle here, and if that is temporarily paralyzed the patient can’t lift their arm. The second nerve is a muscular cutaneous coming down here. That’s a nerve that bends the elbow, and if that nerve is stretched you can get temporary weakness of bending the elbow. And finally at the back is the radial nerve, and that nerve lifts the wrist up so that if you have a radial nerve injury, the wrist drops and that can be a traction injury. Fortunately, in the majority of these nerve traction injuries there is a near normal recovery, but it may take 9-12 months. In the rare instance where a surgeon is really worried that the nerve may have been more severely damaged, the surgeon may suggest a re-exploration, but I’ve only had to do that, in my career, three times and in two of these occasions I found that the nerve was intact and didn’t require any surgery.

Dr. Sechrest: Well, let’s talk a little bit about as we go down the road with a shoulder replacement, months to years after their shoulder replacement. What sort of complications can occur at that point? Are there specific complications that you, as a surgeon, worry about after the surgery has healed?

Dr. Wallace: There are. The first one is the rotator cuff tendons that we talked about earlier. As you get older these tendons get weaker and, in a shoulder that has been replaced, we do see these tendons sometimes tearing 5,10 years after surgery, and the patient knows something’s gone wrong because they’ve had a good shoulder and then suddenly they feel a pain. They can’t lift their arm and they have this sensation of weakness in the shoulder, and they don’t know why it’s happened because it happened out of the blue, and this can be because these tendons have torn spontaneously for no obvious reason, but the real reason is, I’m afraid, it’s an aging process.

Dr. Sechrest: Are there any other complications that we haven’t talked about that you feel like patients need to know as they go forward in their recuperation and perhaps years after they’ve recovered from this operation?

Dr. Wallace: Well, the shoulder replacement is introduced into the bone and is designed to lock into the bone. Either by the bone attaching to the metal stem or the metal socket or using bone cement, loosening of the artificial joint is a problem. It does occur any time from insertion all the way up to 20 years after the operation. We think that later on, perhaps after 10 years, loosening does occur in relation wear complication but we’ve got to make sure the patients realize that loosening can occur. If it occurs, the patients start to get ache and pain in their arm usually, sometimes their shoulder but more commonly their arm, and that pain is aggravated by exercise, by using the arm. Loosening can also occur as a result of a very low grade infection and so any patient, who has loosening, we worry is the loosening related to an infection or not. The other problem we see with the ball and socket joint in the shoulder is that it’s a very shallow socket. It’s not like the hip, and therefore the ball is in danger of dislocating and coming out of its socket. It’s held into the socket by the rotator cuff tendons and the capsule or lining of the inside of the shoulder and, if any of these rotator cuff tendons give way, and particularly the one at the front called the subscapularis tendon, then the shoulder can dislocate forwards and, if that happens and, it slips out of joint, then we are talking about corrective surgery to deal with that. Now that risk of dislocation is probably about 1 case in 30 over the lifetime of 30 shoulder replacements, so it does occur, it is significant, and it does require corrective surgery.

Dr. Sechrest: Well, Professor Wallace, this has been an excellent discussion about artificial shoulder replacement. Is there anything that you feel like we’ve not covered that you would like patients to know about artificial shoulder replacement or shoulder arthroplasty that we haven’t covered up to this point?

Dr. Wallace: I haven’t mentioned up to this point the two designs that are popular. I’ve mentioned the stemmed shoulder replacement with the stem going down the inside of the bone. But the surface replacement has become very popular, really popularized by my friend and colleague, Steve Copeland, and that is a replacement where a metal cup is placed over the ball of the shoulder joint and then acts as a new shoulder joint, and that is proving to be a very good form of shoulder replacement; and particularly useful for the younger patient because, if you put in the ball and they’re maintaining their natural socket and their socket is in good condition, that can last for a large number of years, and then if you do have to revise it it’s an easy revision operation. So the surface replacement is an important step that has taken place over the last 10 years and is something that your surgeon may discuss with you.

Dr. Sechrest: Well, that’s excellent information. Can you think of anything else we’re going to see in the future in terms of shoulder replacement that is perhaps on the horizon that we need to be aware of?

Dr. Wallace: Yes, there is a lot of discussion about biological ways of improving a shoulder that is damaged. As I explained earlier on, the inside of the shoulder has a smooth surface. That surface is a cartilage surface and it’s an important for a normal joint. We are working at producing cartilage which can then be introduced onto the surface of joints to recreate that normal surface and that is already happening in the knee. The shoulder is more challenging and I think it won’t happen this year. It won’t happen in 5 years time, but I suspect in 10 years time we will have a biological way of dealing with early arthritis of the shoulder and that will mean patients don’t have to undergo a shoulder replacement but can be treated with a less invasive treatment.

Dr. Sechrest: Well, Professor Wallace, this has been a wonderful discussion and I think that it’s useful information for all patients who are facing problems with their shoulder such as osteoarthritis of the shoulder, and are considering an artificial shoulder replacement or a shoulder arthroplasty as it’s otherwise known as. So I want to thank you for joining us today. Thank you for sharing this information with patients and hope to talk to you again soon. Thank you very much.

Dr. Wallace: It’s been my pleasure, Dr. Sechrest. I’m very grateful for the opportunity of helping patients understand their problems a little more because if they understand, we can work as a team and get a better result at the end of the day.