Total knee replacement has become a very common elective surgery, and patients are often amazed at how quickly they can get back to "normal" life after surgery. Within hours of their surgery, my patients are often able to begin walking with the assistance of a physical therapist and a walker. While most of my total joint replacement patients can be discharged to home within 48 hours, many are stable for discharge within 24 hours of surgery.
In spite of the anticipated rapid early recovery following total knee replacement, there is still a significant healing process that must occur. This healing process progresses through an inflammatory cascade and continues for over a year from surgery. It is this inflammatory cascade that requires a dedicated stretching regimen to ensure optimal knee range of motion following surgery.
Many patients are concerned that their knee feels warm, and may appear swollen and/or pink in the early post-operative period following knee replacement. In the vast majority of cases, this is normal and an anticipated part of the recovery period. Of course, if there is ever a concern, you should always discuss this with your orthopedic surgeon. Why does this happen? Basically, the body increases blood flow to the knee region to support the healing process. This increased blood flow results in the warmth, swelling and redness often experienced by the patient.
As the healing process progresses, the warmth, swelling and redness dissipate. The warmth can take 6 months or longer to resolve. Swelling and redness generally resolve within a few weeks of surgery.
A bone scan is a nuclear medicine radiological study that reveals bone metabolic activity. It will light up in areas that are irritated such as fractures, stress reactions, tumors and arthritic joints. If a bone scan is performed within 2 years of a total joint replacement, it will show increased bone metabolic activity adjacent to the relatively new prosthesis (even when the prosthesis is functioning properly). This is further indication that the healing process following joint replacement progresses over a very long period of time. Thankfully, the replaced joint usually feels great, long before the body has fully recovered.
So, after total knee replacement you can monitor the healing process by feeling the skin overlying your knee. As your skin gradually cools off, month-by-month, you know the healing process is winding down.
Please note: Severe swelling/redness, drainage from the wound, increasing pain, and/or loss of range-of-motion should not be assumed to be normal. If there is any concern, you need to be evaluated by your orthopedic surgeon immediately.
I previously discussed how important it is to regain full knee extension following total knee replacement. Full knee extension is required for a normal, low energy gait cycle. Anterior knee pain can occur for a variety of reasons, but lack of full knee extension (otherwise known as a knee flexion contracture) will overload the patellofemoral joint (knee cap and femur joint) causing pain. Unfortunately, regaining knee extension after total knee replacement is generally challenging and often uncomfortable. I previously discussed the basic stretches I commonly recommend. Today I demonstrate the prone hang technique. This method uses gravity and relaxation to gently and progressively induce full knee extension.
Here I am lying on my stomach. My left knee (closest to the viewer) is held slightly flexed. This demonstrates the appearance of a knee flexion contracture. Remaining in this position for long periods of time (a minimum of 10 minutes 6 times per day) will result in gradual correction of the flexion contracture. The longer you remain in this position the better. Ideally you would spend a half-hour or more in this position several times each day. A long duration, gentle stretch will allow the viscoelastic biologic tissues to elongate.
By placing my opposite foot on the back of my heel and relaxing, my left knee is pushed into a more extended position. In this case, my right leg provides additional weight, helping gravity force my left knee straight. This may be necessary for more resistant cases of knee flexion contracture.
This is the goal. Full, symmetric extension of both knees.
Here I have placed a sandbag on the back of my ankle to provide additional extension force to my left knee. An ankle weight would also work nicely. Remember, the goal is to relax and allow the soft tissues (posterior capsule) to progressive elongate. This takes time. I recommend spending at least 10 minutes in this position several times per day. Longer is better, and will result in faster gains. Remaining in this position for 30-60 minutes at a time is challenging but ideal.
Time and effort spent regaining full knee extension after total knee replacement will result in better knee function and reduced knee pain for the life of your knee replacement. As with all the stretching techniques I recommend, gentle, progressive, long-duration stretches. Cycling or bouncing the stretch is not necessary and probably irritating/counterproductive. Try to relax as much as possible during the stretch. Remember that some increased pain during and immediately after stretching is normal and expected.
The sooner you are able to regain full knee extension following total knee replacement the better you will feel, the easier your rehabilitation will be, and the more rapid the restoration of an efficient gait cycle.
Traditionally, orthopedic surgeons universally recommended patients with joint replacements take a dose of antibiotics prior to dental work. This practice was generally supported by the American Academy of Orthopedic Surgeons. Recently, this recommendation has come into question with the American Dental Association stating that routine use of antibiotic prophylaxis following total joint replacement is not necessary.
Why the controversy?
Simple. We do not have sufficient data to make a strong recommendation backed up by science. The incidence (regardless of cause) of total joint infection is quite low at around 1-2%. When a problem occurs very infrequently, testing an intervention requires an enormous study to show an effect. Such a study simply has not been done.
Let's look as some more data. While the bacteria implicated in the majority of total joint infections are staphylococcus species, which are mainly found on the skin, infections can also occur due to streptococcus species. The predominant bacteria in the mouth are streptococcus species. We know that bacteremia (bacteria present in the bloodstream) occurs during and after dental work. Whenever bacteria are present in the bloodstream, there is concern that they can be deposited on "at risk" material such as artificial heart valves and total joint replacement prostheses. The tendency for bacteria to be deposited is likely higher in areas of increased and/or turbulent blood flow. Dental bacteria have been isolated from tissues deep within the body. And documented total joint infections due to dental bacteria have indeed been reported. Even native (non-replaced) joints can become infected as a result of oral bacteria following dental work.
Although based mainly on a few case reports, my conclusion is that oral bacteria routinely enter the blood stream during dental work, and it is possible that a deep prosthetic joint infection can result.
So why the controversy? There are different perspectives.
First, orthopedic surgeons know that an infected total joint replacement is a big deal. It usually requires more surgery, sometimes multiple operations and long-term IV antibiotics to cure. A cure is not guaranteed, and even when cured, return to pain-free function is not guaranteed.
Second, dentists. Since there is not overwhelming evidence linking dental work to total joint infections I believe the issue has been minimized a bit by the dental community. I feel the American Dental Association has overstepped the science when stating antibiotic prophylaxis is not indicated prior to dental work. This conclusion was essentially based on a single case-control study. To make such a conclusion, a properly conducted, prospective randomized study on a huge population is required. Dentists do not directly see or have to take care of a total joint infection and therefore may under-estimate the magnitude of such a problem. Perhaps also distancing the dental field from orthopedic infections could be felt to minimize liability in such cases. Interestingly, most local dentists actually encourage prophylactic antibiotics in spite of the ADA recommendations.
Third, population health. Antibiotic overuse is not without consequence. There are multi-drug resistant bacteria that have evolved in part due to the tremendous volume of antibiotic medication used worldwide. (Of course the vast majority of antibiotic use is in veterinary medicine and food production, which is clearly a topic for another blog posting.)
Fourth, the total joint replacement patient. Antibiotics can be associated with negative side effects, allergic reactions, and secondary infections. So we need to carefully balance the risks and benefits. As I have outlined above, this is challenging because the risks and benefits have not been clearly defined scientifically.
Here is my approach. I recommend all of my total joint patients take a single dose of prophylactic antibiotics prior to dental work for a minimum of 2 years following surgery. 2 years is significant because we know there is increased bone metabolic activity (increased and turbulent blood-flow) around the total joint prosthesis during this time. If a standard-risk patient wants to use antibiotic prophylaxis in this way indefinitely, I would not deny them the antibiotics after carefully discussing with them the risks and benefits. I recommend any high-risk patient (immunocompromised, diabetic, cancer, rheumatoid arthritis, etc) take a single dose of prophylactic antibiotics prior to dental work forever.
With this approach, I am clearly biased in favor of my patients over the general population. In other words I feel that the single antibiotic dose I prescribe to my patients every six months is unlikely to have a major negative effect and also very unlikely to make a major contribution to worldwide bacterial resistance. Antibiotics are used in far greater quantities in the veterinary medicine and food industries, and are also inappropriately used in viral illnesses where they will have no benefit. Although prosthetic joint infection is rare at the population level, sparing an individual patient such a negative experience is a tremendous benefit.
When I eventually undergo a joint replacement, based on my current understanding of the issues, I plan on using prophylactic antibiotics forever.
When can I drive?
This is a very common question patients ask following surgery. Some studies have suggested that reaction time and/or braking force is reduced for weeks or even months following total knee replacement surgery. This could lead us to recommend that patients do not drive for a prolonged period of time following total knee replacement surgery. Logistically, this can be challenging.
A recent study showed that patients with osteoarthritis of the knee (without having undergone knee replacement surgery) had reduced driving ability based on diminished reaction time, movement time, and they ultimately had reduced braking performance. In spite of these findings, is not reasonable to tell patients with osteoarthritis of the knee that they can never drive.
A brand new article in the Journal of Arthroplasty shows that 80% of patients have regained their pre-surgery braking performance by 2 weeks following total knee replacement. All patients in this study were back to baseline by 4 weeks.
This reinforces my standard recommendation, but still leaves out one key issue. Pain medication. Narcotic pain medication is commonly used for several weeks following total knee replacement. This can impair driving skill and reaction time independent of knee surgery.
My recommendation to patients after total knee replacement surgery is that they should not drive while they are using narcotic medications. Furthermore, they should not drive until they feel comfortable doing so. This time period is patient specific, and there is a wide range. Common sense should prevail. I believe patients generally know themselves, and certainly do not want to place anyone at risk by driving prematurely.
I recommend patients focus as much as possible on rehabilitating their new total knee replacement for the first few weeks, limiting their driving to the essentials: food shopping, physical therapy, and follow-up with their orthopedic surgeon. Soon, their pain level will be down, and their confidence to drive will return.
We can then add driving to the list of lifestyle improvements made possible by total knee replacement.
As always...please discuss specific recommendations with your surgeon.
Non-operative treatment for osteoarthritis includes activity modification (do less, reduce impact, reduce load, reduce distance, etc), topical medications, oral medications, bracing, and injections.
A common injection used in orthopedic clinics many times each day is generically referred to as "cortisone." It is a combination of a local anesthetic (like the dentist uses) and a steroid. There are a variety of local anesthetic agents used (lidocaine, bupivacaine, etc.), and a variety of concentrations available. Additionally, there are a variety of steroids that can be used. Each surgeon likely has a preferred combination.
Just a side-note: the steroids orthopedic surgeons inject for anti-inflammatory purposes are completely different from the anabolic steroids associated with body-building. They will not make you grow muscle.
Although not everybody responds the same, a cortisone injection often provides rapid and significant relief from arthritis pain. This relief can last for months. When the pain returns, we have a discussion regarding the amount and duration of relief experienced. I generally allow my patients to undergo up to 3 cortisone injections per joint, per year.
Some patients aggressively pursue these injections and would accept them much more frequently than I recommend. Others prefer to avoid them entirely. Reasons for this vary. Some patients are simply afraid of the needle. This is a shame, because most patients report only mild discomfort when I've performed a cortisone injection. Other patients are more concerned about the potential detrimental effects. They've heard that cortisone destroys cartilage and will hasten their joint deterioration.
Some in vitro (test tube) and animal studies have shown chondrocyte (cartilage cell) toxicity due to local anesthetics, steroids, and combinations of both. Cartilage cell damage in a test tube does not necessarily mean that an injection into a living human's joint will create similar damage. In fact, another study in which samples of living cartilage were taken after the knee was injected with local anesthetic showed no such effect. While I certainly understand that cells in culture may be negatively effected, I have seen no clinical evidence of joint destruction due to cortisone.
I think it is reasonable to assume, like with most medications, that while there is a benefit, there is also some potential for harm. The key is to use cortisone, like all medications, judiciously. That is, only when indicated, not too often, and at the lowest effective dose.
It is important to remember that we are using cortisone in joints that are already moderately to severely damaged due to arthritis. The joint is already irreversibly damaged due to the cumulative effects of gravity, activity, and time. A cortisone injection can provide a significant improvement in quality of life and can potentially delay surgery.
Remember, a total joint replacement involves removing ALL of the cartilage from the joint. I would argue that that is much more toxic to the cartilage than a few cortisone injections.
I am not suggesting people should not have their joints replaced when they wear out. The majority of my practice involves replacing destroyed knees, hips, and shoulders. These operations predictably alleviate pain and restore function. Total knee, total hip, and total shoulder replacements, help hundreds of thousands of patients every year in the U.S.
I am suggesting that appropriate use of cortisone can allow some patients to delay an operation, sometimes for years. And if there is a risk that microscopic cartilage damage occurs, the ability to reduce pain and delay surgery is worth it.
Although playing tennis can result in tennis elbow, most cases of tennis elbow, also known as lateral epicondylitis, are actually due to overuse when working with the hands. A tendon is the tissue that attaches muscle to bone. The suffix "itis" means inflammation, and while acute overuse injury can cause inflammation, the typical case of tennis elbow is more chronic, due to repeated overuse, and results in degeneration of the tissue. This situation is more appropriately called "tendinosis."
The pointy bone that sticks out on the outside of the elbow is called the lateral epicondyle. This is the common origin of the wrist extensor muscles which cross the elbow and then cross the wrist. It is this tendon that is injured with tennis elbow.
So, when attempting to grip something firmly, the wrist extensor muscles (that attach to the outside of the elbow called the lateral epicondyle) contract firmly. This is fine. Now when elbow range of motion is added simultaneously, the wrist extensor muscles experience shearing, or variation in the force they experience, while the elbow moves. Additional irritation like a short rapid wrist flexion force can sometimes occur. This combination of forces can create trauma to the extensor muscle group at its insertion point on the lateral elbow (lateral epicondyle).
A perfect example of the above scenario is when the tennis ball makes contact with the racket during a backhand swing, hence the name tennis elbow.
A more common situation in my practice would be swinging a hammer all day, scraping paint, or pulling weeds. Basically power grip with the hand superimposed on simultaneous wrist and elbow range of motion.
Acutely, micro-tears can occur in the muscle origin on the outside of the elbow (lateral epicondyle). This can create pain and inflammation. When allowed to rest and recover, the issue resolves. However when the overuse occurs repeatedly, and the micro-tears are not allowed to fully resolve prior to additional trauma, the condition can become chronic. The normal tendon tissue (a tendon is the tissue that attaches muscle to bone) breaks down, and the tissue becomes disorganized and weak (tendinosis).
Lets talk about treatment. It is important to know that proper non-operative treatment will cure 90% of people. Unfortunately, especially in chronic cases, it can take months to resolve.
Also known as patellofemoral syndrome, anterior knee pain can be extremely frustrating for patients and surgeons alike. Anterior knee pain is extremely common and can have a variety of causes. Patellofemoral arthritis (knee-cap arthritis), and knee-cap dislocation (patellofemoral instability) are two diagnoses that can cause anterior knee pain, but they each will require a separate blog posting of their own.
Patients experiencing patellofemoral syndrome complain of aching pain in the front of the knee which can range in severity from mild to intense. It is often made worse by sitting with the knee bent for a prolonged period (movie theater or back seat of car). In this situation the pain can be improved by extending the knee (straightening it). Climbing or descending stairs can also be quite irritating.
This condition affects people of all ages and of all fitness and activity levels. I have diagnosed and treated this condition in marathon runners, adolescents, and patients who previously underwent total knee replacement. Usually the problem gradually worsened and has been present for a fairly long time when it gets to me. The key to the diagnosis is to listen to the patient. The history given tends to be very consistent.
To better understand this condition, let's start with some background information.
The patella (knee-cap) is subjected to the greatest force of any cartilage in the body (3-5 times body weight during normal activity and up to 10 times body weight when jumping). It is embedded within the extensor mechanism of the knee so that it can provide leverage to the quadriceps muscle group. The front of the knee is richly innervated and is thus very sensitive to abnormal pressures. The position of the femur (thigh bone) during activity will change the amount and distribution of forces on the patella.
There is a very consistent examination finding associated with this diagnosis. Patients usually will have very weak hip flexors (muscles than bring the thigh forward relative to the torso) and hip abductors (muscles that bring the thigh away from the midline). Usually the hip external rotators will also be affected.
What does the hip have to do with the knee-cap?
The hip flexors and abductors are very important during the gait cycle (walking). The abductors must contract with great force to keep the pelvis level during single leg stance. The hip muscles together act as the "foundation" for your leg. If they are weak, your leg will be poorly controlled when walking. This can result in abnormal gait mechanics, abnormal rotation of the femur when weight bearing, and abnormal patellofemoral mechanics.
This combination of issues multiplied over thousands of steps each day can result in anterior knee pain.
Ok, so how do we fix it?
My recommendation is to focus on the hip. Strengthening the weak hip muscles will almost always result in a cure. Unfortunately, this can sometimes takes weeks or months. Remember, we are rebuilding muscles that have gotten deconditioned over a long period of time. This takes time. Knee pain gradually resolves as hip strength gradually improves. The exercises I recommend are very simple:
Keep your knee locked in extension. Raise your leg from your hip keeping your toes pointing toward ceiling. Up and down counts as one repetition. Aim for a set of 30 repetitions. Then add sets.
It is important to do these exercises on both sides, even if only one knee hurts. You want to keep things balanced.
Lateral raise. This exercise focuses on the hip abductor muscles. Lying on your side, slowly elevate the leg from your hip, keeping your knee straight and your toes pointing forward (not toward the ceiling). You should feel the burn on the side of your butt.
So, that's basically it. Remember, we are building hip muscles. It takes time. I recommend doing these exercises on both sides (even if only one knee is painful) so everything stays balanced. Each repetition should be done slowly when raising and lowering. You may be surprised by how challenging this set of hip exercises can be. You should work up to 3 sets of 30 repetitions for each muscle group. Repeat the workout twice per week. The total work-out should only take about 15 minutes. Resist the urge to do these exercises more frequently. The purpose of exercise is to stimulate the muscle to grow. It then needs to be allowed to grow, and this takes time. Stimulating the muscles with resistance exercise too frequently will be counter-productive.
When doing this exercise becomes easy, feel free to add some additional resistance. You can wear a boot, or use an ankle weight.
It is a common misconception that one should exercise the quadriceps using a leg extension machine. This is a mistake and I would strongly suggest avoiding any knee isolation exercises in general, but when dealing with patellofemoral syndrome in particular. The knee extension machine will worsen anterior knee pain.
Be patient, and consistent with these exercises. As your hip strength improves, your knee pain will improve as well.
In a previous post, I described what I feel to be the most important shoulder stretch. It is very important functionally to be able to reach out in front of you, and to reach overhead. While my focus in the prior post was frozen shoulder (otherwise known as adhesive capsulitis), the stretch I described is very useful for regaining function after rotator cuff surgery, shoulder labral repair surgery, and trauma. The anterior and inferior (front and bottom) shoulder capsule/ligaments are stretched using this technique.
(Please note: If you are dealing with a frozen shoulder, this stretch may be too irritating to begin with. I recommend you begin with anterior, inferior capsule stretching using the best stretch for a frozen shoulder. You can come back here once you have regained the ability to raise your arm over your head again.)
Sometimes, in spite of having done an outstanding job rehabilitating their shoulder following surgery, a patient may have some residual pain. Another common subset of patients presents with shoulder impingement syndrome or bursitis. These patients report pain which is usually lateral arm pain, aching in character, and may be worse at night. If forward elevation (reaching overhead), and abduction (reaching out to the side) are near normal, and rotator cuff strength is good, it is important to focus on the posterior capsule (ligaments in the back of the shoulder).
A tight posterior capsule can cause abnormal shoulder mechanics. This can cause the shoulder ball (humeral head) to translate superiorly (upward) when raising the arm instead of rotating in the socket (glenoid). This pinches the rotator cuff and causes pain. The rotator cuff normally pushes down on the humeral head during rotation, but when it is irritated it will get lazy. Unfortunately, this compounds the problem, and allows the humeral head to further translate upward during activities. A cycle is then created whereby the problem gets progressively worse.
We need to break this cycle.
When I find the posterior capsule to be tight, I recommend using the sleeper stretch. This is a simple stretch that a patient can do on their own. As always, I recommend stretching every day, with no days off. I also recommend gentle progressive static stretching. That is, slowly applied pressure that is then held at the endpoint for relatively long duration. This means minutes rather than seconds. We are taking advantage of the viscoelastic nature of our soft tissues. The posterior capsule tends to be relatively thin tissue, and thus, this stretch does not require high force.
In these photos I am lying on my side. For this demonstration we will assume my right shoulder is the bad one. So, I am lying on the bad side. My elbow is out in front of me. The upper arm should be even with the shoulder. Both palms are facing toward my feet. Now gently and progressively apply force with the left hand. The goal should be to create rotation of the right palm toward the floor.
This should create tension and stretching pain in the back of the shoulder.
Ordinarily I would recommend resting your head on a pillow for comfort. I am not doing this to avoid obscuring the positioning.
Here is the view from above. Again note my upper arm is at shoulder level and my palms are facing toward my feet.
Pressure is applied rotating my right shoulder internally, and pushing palms toward the floor.
Here is a less aggressive position. It may be good to begin this way.
You can place a pillow behind your back to lean against. For all of these positions, resting your head on a pillow will allow more relaxation and thus a more pleasant stretch that you can hold for a longer time period.
This is the most aggressive sleeper stretch position. This will concentrate more force on the posterior capsule. It may not always be necessary to regain balance. I recommend testing each of this positions on the other (good) side so you have a benchmark to assess what is normal for you.
Some key points:
How much motion should you have at any given point after surgery? Of course, you should speak to your surgeon about the specifics of your case. However I'd like to provide some general guidance on this subject.
During knee replacement surgery, the knee will be reconstructed using a metal and plastic prosthesis, and the ligaments balanced. At the conclusion of the operation, the knee will be able to fully extend (straighten) and fully flex (bend back). After surgery, although initially pain will prevent full range of motion, scar tissue has not had a chance to form. Most patients are able to move from full extension (0 degrees) to 90 degrees (foot flat on floor while sitting in normal chair) within 24-48 hours.
It is not uncommon for patients to lose a bit of motion around 7-10 days from surgery. This is a result of increased pain and swelling due to the inflammatory cascade. This inflammation peaks around 10 days from surgery. It is ok to go a bit easy on yourself during this time. Use plenty of ice and anti-inflammatory medication if it is allowed by your surgeon. But keep stretching. Do not allow yourself to lose full extension. This is crucial.
By the first postoperative visit around 2 weeks from surgery I would like to see a minimum of 0-90 degrees of motion.
By 6 weeks from surgery I would like to see 0-120 degrees minimum.
Patients may gain an additional 5-10 degrees of deep flexion over the course of the first year following surgery if they've gotten to 120 degrees by 6 weeks.
If these parameters are not met, other options are available. I begin asking patients to follow-up with me every other week or more to track their progress, to answer questions, and provide motivation and support. I understand that this process isn't always easy and is never fun. If inadequate range of motion isn't achieved by 6 weeks, I then recommend manipulation under anesthesia to break up scar tissue that has been allowed to form. This buys us some time and generally gets things back on track.
In an earlier post, I described my experience with a frozen shoulder. Here are some pictures showing exactly how I rehabilitated myself and how I recommend my patients stretch on a daily basis.
The initial position will look something like this. I am using a jar of sauce to provide some downward pressure. My good arm is placed in a similar position and allowed to rest with the shoulder, elbow, and wrist touching the floor. When your bad shoulder is hurting from the stretch, look over at your good shoulder and remind yourself what normal range of motion looks like.
This is the goal. Now I am able to touch my shoulder, elbow, and wrist to the floor at the same time.
You will not get to this point quickly. It will likely take hours of stretching like this over weeks to go from the first picture to this one.
Here is how it looks from above.
Gradually bringing your hand and elbow closer to your head will add additional stretch.
Some key points:
Orthopedic Surgeon focused on the entire patient, not just a single joint.