COI: Hip and Knee Pain?
Thanks for tuning in, my name is Steve Nelson and I’m an orthopaedic surgeon at the Connecticut Orthopedic Institute at MidState Medical Center. I specialize in hip and knee replacements and today I’m going to talk about treating hip and knee pain. So to start off with, I wanted to share a little bit about me. I’m part of Connecticut Orthopaedics. I’m originally from Connecticut but went to Wheaton College in Illinois for my undergraduate degree and then attended med school at the University of Connecticut. After med school, I did my residency at Yale in New Haven and then did an additional year in advanced training specifically in joint replacements at the University of Virginia.
So, we have a number of topics for today’s talk. I’m going to begin by discussing the various causes of hip and knee pain, then we’ll proceed to discussing treatment options both non-surgical and surgical, we’ll eventually discuss the place for joint replacement surgery and then talk about recovery expectations after a hip or knee replacement.
Your hips and your knees are involved in almost every activity that you do. In this age of social distancing, oftentimes getting out of the house to take a walk is one of the only escapes that we can have, but a painful hip or knee that is diseased or injured really limits that ability to move or work.
Joint pain comes from arthritis and the word arthritis comes from “arthro” meaning joint and the suffix “itis” meaning disease of or inflammation of, so if you have an inflammation of the joint, it’s arthritis. It’s incredibly common, it affects the lives of around 54 million Americans. Rheumatoid arthritis is an autoimmune disease where the body’s immune response attacks the joint lining and it causes chronic inflammation and pain. Osteoarthritis is kind of the wear and tear arthritis, it’s a degenerative process or you have a broken tip of the cartilage, the meniscus, and then the joint in general. As the bones rub against each other, it causes pain and stiffness. Lastly, there’s post-traumatic arthritis which can develop after an injury to the joint in which the bone and cartilage don’t heal properly.
So, let’s start off by talking about non-surgical treatment options. I’m a firm believer in exhausting all non-surgical treatment options before even considering an operation and truthfully these treatment options will provide significant benefits of the vast majority of patients who have mild to moderate hip or knee arthritis.
The first non-surgical treatment option is a walking aid like a cane or a walker. These walking aids can help you put less pressure on the affected joint. I don’t get any compensation from any cane companies but the cane that I prefer most is called “The Hurrycane”. What makes it nice is that it is freestanding and actually has this self-balancing, pivoting base which provides better stability. Truthfully, any cane works but this one just happens to be my favorite.
The next non-invasive, non-surgical treatment option is either heat or cold therapy. Often times, just temperature alone can help to provide significant relief to an achy hip or knee joint. Patients often asked me whether to use heat or cold and the truth is you should do whatever makes you feel better. Most often this means heat if you’re going to go warm up and exercise the joint but cold if the joint is already hot or swollen or inflamed. The one tidbit I would offer is that if you are going to use cold or ice, you shouldn’t use it for more than 20 minutes at a time. When you do use ice for more than 20 minutes, the body starts to think it’s going into hypothermia and it can induce an inflammatory reaction which is counterproductive to the reason that you were using ice in the first place.
Next is Physical Therapy. It’s also very important in the treatment of hip and knee arthritis. A skilled physical therapist is worth their weight in gold, they can strengthen your legs and your core muscles. They can also lessen your pain by teaching better posture and form for your day-to-day activities.
Next is anti-inflammatory medications. These are also incredibly important in the the treatment of arthritis. There are several types of anti-inflammatory drugs in the market. The first three that you see there are the ones that are available over-the-counter: aspirin, ibuprofen, and naproxen. The next three, meloxicam, celebrex, and indomethacin requires a prescription. You know these drugs do reduce pain and swelling but they they can have some side effects. They do increase your bleeding risk, if you have kidney problems, it can make them worse, it can cause stomach ulcers, it could give you high blood pressure. If you have a history of bleeding or taking blood thinner, if you have kidney problems or a history of high blood pressure, you should really speak with myself or another physician, before taking these medications.
And people who are overweight or obese, weight loss is crucial in improving hip or knee pain. Biomechanics of the knee, or just that for every pound on the Torso, is equivalent to 4 pounds on the knee and 7 pounds on the patellofemoral joint. So that means if you lose 10 pounds in your waist, that’s 40 pounds off your knee and it’s 70 pounds off the patella which really dramatically improves symptoms in a lot of people.
The next non-surgical treatment option I wanted to discuss was arthritis supplements. I think there’s certainly a lot of them. I recently Googled “arthritis supplements” and found 108 million results. It’s really hard to know where to begin. Arthritis supplements you may have heard of include capsaicin, glucosamine, turmeric or curicumin, fish oil, ginger and there’s a number of other supplements that are not regulated by the FDA but can help your symptoms, however, they can be expensive. My personal favorite supplement is turmeric, which acts as an anti-inflammatory and I really have had some success within certain patients. With Nexis injections, they can be quite helpful and there are two main types of injections. There are steroid injections or cortisone injections. It’s like the catalog here on the left and then there’s mana discs or gel injections and from the right, the steroid injection has to decrease the amount of inflammation in the joints and depending on how advanced the arthritis is, it can last anywhere from 1 week to 1 year. That averages around 3 months. Gel injection, on the other hand, functions to re-lubricate the knee joint and often last for a few months. Unfortunately, there’s no crystal ball to determine the efficacy of a knee joint injection, and depending on the severity of your arthritis, an injection is often worthwhile prior to considering surgery. So I firmly believe in delaying joint replacement surgery as long as you possibly can, however, once you’ve tried all these non-surgical treatment options, you need to start to ask yourself a number of questions. Is the joint pain affecting your ability to get a good night’s sleep? Does the joint pain keep you from doing the things you want to do? Are you less active because of the joint pain? Or is it affecting your ability to walk up stairs? When the answers to one or more of these questions is ‘yes’, and you’ve exhausted the other non-surgical treatment options, it’s time to start talking about a new hip or a new knee.
So let’s start by discussing total hip replacement. The best way to start to understand hip replacements is with a basic understanding of the anatomy involved. The pelvis and the femur are connected to the hip joint or this ball and socket joint where the femoral head articulates with the acetabulum, which is the socket. Where the two meet in the healthy hip, there should be a thick layer of cartilage that cushions the hips from the bony impacts of weight-bearing. However, when you have disease cartilage, as in the image on the right, the cartilage is unable to shield the brunt of the force of weight-bearing and you feel arthritic pain. This typically occurs in the groin. Here are two hip x-rays. The one on the left is normal and you can see where the femoral head connects to the acetabulum, there’s a nice grey line that goes between the two of them, two bones, and that’s where the cartilage lives. That means there’s a good healthy layer of cartilage and that’s a nice healthy, noble hip on the left. Rather, on the right, you can see there’s quite a bit of arthritis. That gray line where the cartilage used to live is gone. There’s sclerosis, or whitening of the bone or hardening of the bone and you can see bone cysts both in the femur as well as in the acetabulum. Finally, you’ll also notice that in contrast to the left and normal hip where the femoral head is nice and spherical and circular, the hip on the right has lost that disparity and if you have a ace spherical ball rotating in a cup, it’s really going to grind and be quite painful.
Alright, so, let’s talk about total hip replacement and how it works. This is going to show you a virtual patient. If you strip the skin in the musculature around the hip, we see the femoral head and acetabulum. In order to create room to prepare the acetabulum, we remove the femoral head and prepare the bone source that accepts a hemispherical titanium prosthetic socket. In that side that socket goes a plastic liner made of polyethylene. Next, we prepare the femur with a femoral stem that fits the shape of the inner cortical surface of the femur and a femoral head goes on that stem. Together, these components, when they function properly, can eliminate that bone on bone hip arthritis pain. So again, there are four components to each hip replacement. You have the femoral stem that goes into the femur, the acetabular cup, and then the liner that goes inside the acetabular cup, and the femoral head. This is an x-ray of a replaced hip, you can see again the stem that goes into the femur, the acetabular cup, the femoral head, and this is a nice x-ray. It has nicely reproduced the patient’s leg lengths, they’re offset. This is a well done hip replacement. Here is what the hip replacements look like up close. If you look carefully, you can see the acetabular cup and the femoral stem. Both have a great blasting or a bone ingrowth surface and your own bone actually interdigitates with these roughened edges on the implants themselves.
The polyethylene, the plastic liner, is often white and the femoral heads that we use nowadays are most often ceramic.
Next, I wanted to discuss a bit about muscle-sparing approaches in hip replacement. Truthfully, there are a lot of correct ways to do these operations and as long as the implants are positioned properly, the long-term results will most likely be fantastic. However, if I were going to have my hip replaced, I would want it done through the direct anterior approach which is the main surgical approach that I use. So in contrast to the posterior approach, which requires a much larger incision, you have to cut through muscle and tendon and you actually cut those fibers. The direct anterior approach is a much shorter incision and leaves all the muscle tissue intact. This functions to accelerate the post-operative recovery and it also significantly decreases at the risk of dislocation which is a dreaded complication after hip replacements. With a traditional posterior approach, patients are required to maintain certain hip precautions or they can’t excessively bend or rotate their hip after surgery to prevent a dislocation but fortunately with the anterior approach, these precautions aren’t necessary.
So let’s move on to talking about knee replacements. Again, the best way to understand knee arthritis is with an understanding of the anatomy involved. The femur is the thigh bone and the tibia is the shin bone. Where they come together, you have your patella or kneecap. Usually, there’s a healthy layer of cartilage that prevents the patients from feeling the brunt of those bone on bone forces. However, if you have diseased cartilage or that cartilage is missing, you certainly do feel the full brunt of that pain. So on the left side, we see a healthy knee, again, this is the tibia which is the shin bone, the fibula, the patella, and the femur and in between the tibia and the femur is this nice gap where the cartilage lives and that’s a good healthy knee joint. With a thick layer of cartilage, it’s able to absorb the impact of the bone rubbing on the bone. However, on the right is an arthritic knee, and you see, you don’t actually see that gap between the tibia and the femur and there’s no cartilage there so this patient has bone on bone arthritis.
Alright, so let’s take a look at how knee replacement works in this. So in this virtual patient, let’s see if I can get this video to work, if we remove the skin and then remove the muscles and the tendons if we were to strip those away, you would see the diseased bone ends which grind on each other. My job during a knee replacement is to resurface those bone ends and cover them with a metal and plastic covering for our new prosthetic articulation so that the tibia now glides smoothly on the femur. There are multiple types of knee replacement, either complete knee replacements or partial knee replacements. On the right is an example of a total knee replacement which is just like what was shown in the video, where you replace the entirety of the knee joint. On the left is a partial knee implant which we can perform if a patient only has damaged to a specific part of their knee. This only resurfaces, kind of, those diseased or injured or damaged parts. Knee replacements are incredibly common. There are around 600,000 knee replacements that are performed in the U.S. each year. Here again we see some of the various types of partial knee replacements. If a patient only has damage in the medial tibia femoral compartment, we can talk about doing a medial partial knee. The same goes for the lateral tibial femoral compartment. We talked about doing a lateral partial knee. In addition, if the patient only has arthritis underneath their kneecap, well then we can do a patella femoral replacement.
Patients who have a partial knee replacement typically have much faster recovery after a knee replacement. The patients who do have a full knee replacement, additionally patients with the partial knee oftentimes note that their knee feels a lot more normal than the patient who has a full knee replacement.
Here are some x-rays of knee replacements. The x-ray on the left is a partial knee replacement, this is a medial partial knee. The patient only had arthritis on the inside of the knee and so only that part was replaced. The x-ray on the right is a total knee replacement. We see in the front and then again from the side, you can see that the congruity of the femoral component, you know, really matches the, what the femur should look like and so we’re able to really resurface those bone ends. I typically use Stryker components for my knees. On the left, you see what their partial knee looks like with the femoral component, the polyethylene spacer and then this is the tibial component. This is a patella femoral. This is the femoral component of the patella-femoral replacement. On the right is a cement-less version of their total knee. This is the tibial component. The polyethylene, or plastic liner, the femoral component, and here is the patellar button which we use when we resurface the kneecap itself. I happen to use robotic arm assistive technology for my knee replacements. Strikers’ version of this technology is called the “Mako System”. This is what the robot looks like. It’s a position next to me while I do the operation. Mako certainly has a number of benefits. It does allow surgeons to be more accurate with their implant placement. It also allows for a quicker recovery and lower pain scores postoperatively in certain patients.
Let’s take a look at this robot and get a better idea of how it works. It all starts with a CT scan of the knee joint. A CT scan is basically a series of x-rays that allows me to see things that I wouldn’t, otherwise, really wouldn’t be able to see with an x-ray alone and the CT scan data is used to generate a virtual three-dimensional model of the patient’s unique anatomy. That three-dimensional digital model is uploaded in the Mako system software, which is used to create the personalized preoperative plan. I’m then able to review the bony architecture to identify implant size and, firstly, find the ideal implant position, during the surgery, and then locate points on the patient’s knee in order to register the patient’s anatomy to my three-dimensional digital model. This process establishes the relationship between the CT scan model and the patient’s actual anatomy which helps to ensure that the procedures executed exactly according to plan. Once the anatomy is registered according to the 3D model I created, I have the flexibility to modify my preoperative plan based on my assessment of ligament balance and range of motion. After I’m satisfied with my plan, I guide the robotic arm to remove the arthritic bone and cartilage in the knee. In contrast to it to a conventional knee replacement, there’s a tactile boundary that’s established by the robot which only allows me to take the smallest amount of bone allowable with the original preoperative plan. You can see the image on the left, where, which provides visual cues to show exactly what bone is cut so I can be less invasive. With the diseased bone gone, a knee implant is then inserted into the joint space and once I’m satisfied, it’s off to the recovery room to begin strengthening the knee joint. Overall, this is a very exciting technology and personally how I would want my knee replacement to be performed, if given the option by a competent surgeon. It’s really exciting.
Okay, great. So let’s move on to talking about recovery after joint replacement. Everyone has a slightly different recovery and much of it depends on individual patients function prior to surgery. So, for example, a 90 year old woman who has been wheelchair bound for the last 5 years, due to debilitating hip arthritis, is typically going to have a much slower recovery than a 50 year old man who only has a left knee problem. Overall, my patients typically recover in the hospital for a day before going home and then I do have several patients who leave the day of surgery and that is certainly reasonable, but a little bit less common. Most patients are worried about the pain associated with an arthoplastic procedure, however, our nerve blocks are so good they actually last for 4 to 5 days after the procedure and typically get patients through the worst of the post-operative pain and they’ll make you walk and climb stairs within hours after the operation. Oftentimes patients need a cane for the first few weeks, but most people should get back to their daily activities in 3 to 6 weeks. Typically patients can expect a full recovery where they get back to work within 2 to 3 months and all activities by about 4 to 12 months. The reason to do these joint replacements is to get patients back to doing what they love whether it’s walking, driving, biking, swimming, golfing or dancing, however, it’s important to understand that no joint replacement is every truly as good as what God gave you in the first place. Because of that, I discourage activities that place excessive stress on the replaced joint. Some examples of high joint stress activities are listed below, and truthfully I don’t strictly adhere to this. I think skiing and jogging are still okay, however, I get nervous when my patients are doing activities where both feet leave the ground. If you were to break the bone around one of these joint replacements, it is fixable, it’s just difficult with a long recovery. So this has been an awful lot of information in a very short period of time. If you have any questions, I would love to answer them. My number is listed to the right. Please call and I’d be more than happy to discuss your specific situation in the office. Be well, stay safe, and thanks for your time.