FAQ Category: Knee

Death is a possible complication with any surgery. It’s certainly the most serious one. Death rates after knee replacement (one or both) are very low. Reports do show an increased number of deaths when both knees are replaced at the same time compared to doing one knee at a time.

Data from a large study of 339,152 total knee replacements shows the death rate to be less than one percent (0.99 percent). This figure shows deaths in the first month after the operation when both knees were done at the same time. The death rate for patients having the second knee done three to six months later was lower (0.30 percent).

In either type of surgery, the risk of death is higher if the patient has a history of heart or lung disease. Older age (over 70 years) is also a risk factor.

Many doctors use a guide called the Knee Society Score to measure outcomes or “success” after a total knee replacement (TKR). Points are given for pain, range of motion, and knee stability. There’s a separate score for function based on the ability to go up and down stairs and walk without help.

The scoring system is set up so that age or a medical condition won’t affect the rating. This is especially important for the patient who has good range of motion on the operated leg, but pain and stiffness on the other arthritic side.

Doctors may label a TKR a “success” based on X-ray findings that show the implant in good alignment. If the patient doesn’t have pain and doesn’t mention the stiffness, the same “success” rating may be given.

There may be a treatable source of your knee stiffness. Perhaps a rehab program beyond the TKR exercises is needed. Make an appointment for a follow-up visit and ask your doctor to re-evaluate your results.

This is a decision best left up to you and your surgeon. Some say this is too far away to wait if you are losing function now because of pain and stiffness. Other doctors in large
research hospitals are already using these methods. You might want to look into it if you are close to any facilities where this kind of surgery is being done.

A recent opinion published by Dr. Thomas Parker Vail advised surgeons and patients to ask some hard questions such as:

Your question is a good one. The three parts of a full knee joint implant include: (1) a polished metal shell that fits over the lower end of the femur (thigh bone), (2) a plastic and metal platform that covers the top of the tibia (lower leg bone), and (3) a plastic piece that goes on the back of the kneecap to help it glide smoothly when the knee bends and straightens.

It is possible to have only half of a joint replaced. This is called a hemiarthroplasty. Most of the hemiarthroplasties are done in the hip or shoulder. The knee is different and must be replaced completely. This is because of the ligaments that criss-cross inside the knee.

It is possible to have the femoral and tibial parts replaced without the patellar piece. If the back of the patella is smooth and tracks well up and down over the joint, then it can be left alone. The process of fitting a plastic piece onthe back of the kneecap is called patellar resurfacing.

The knee joint consists of three parts: the knee cap (patella), the femur (thigh bone), and the tibia (lower leg bone). A knee joint replacement is done when arthritic changes cause pain, swelling, and loss of knee function.

Arthritic changes occur inside the knee joint as well as behind the patella. The patella may need to be resurfaced for a successful joint replacement. This means a metal or plastic backing is added to the patella. This helps it ride smoothly over the other parts of the implant when the knee moves.

Not every patient needs patellar resurfacing. Doctors decide whether or not to do this when they look at the back of the patella during the operation. The doctor looks at the
shape of the patella and the condition of the cartilage when making this decision.

Selective resurfacing refers to the fact that not all patients have the patella resurfaced, only those who need it based on the surgeon’s exam.

Having both knee joints done at the same time is a hotly debated topic among doctors. Studies have been done comparing staged total knee replacements (TKRs) and bilateral simultaneous TKR.

Staged surgery means the patient has one knee done, and then waits six months to have the second one done. Bilateral simultaneous TKR means both knees are done at the same time. The bilateral method usually does save time and money, except when complications occur.

Patient selection is the key to reducing the risk of complications after bilateral simultaneous TKRs. Patients should be younger than 70 years old and in good health. A previous history of heart disease is a big risk factor for heart and lung problems with bilateral TKRs. Studies show a threefold increase in heart and lung problems after having
both knees replaced at the same time.

Many studies have repeatedly shown that final knee motion after replacement depends on preoperative motion. It’s also true that patients with the greatest loss of motion have better results than patients with minimal loss of motion.

Recently a group of researchers in England and Canada got together to review the results of total knee replacements. They were especially interested to see what factors predict final motion measurements.

They found that age, gender, and body weight didn’t seem to make much difference. Likewise the type of implant was no longer such a big factor. The amount of knee flexion before replacement was still pretty important.

It’s likely you’ll notice some difference with the new implant. Let us know how you compare them!

There are some reports along these lines. Some studies show that obesity has a negative effect on knee motion. Doctors think the force of the extra body weight causes soft tissues around the joint to get pinched between the femur (thigh bone) and the tibia (lower leg bone). The result is restricted range of motion, especially into flexion.

Other studies don’t agree. In a recent study at the London Health Science Centre, body mass index (BMI) wasn’t linked to postoperative range of motion.

It’s possible that today’s improved implant technology has done away with problems related to body weight and alignment.

Orthopedic surgery for joint replacement is an option for some patients with hemophilia. New drug therapy with inhibitors has allowed surgery to be done safely. It may depend on the type of missing platelet factor. The overall health of the patient can make a difference, too.

Rehab is offered before and after the operation. A preoperative rehab program is called prehabilitation. Exercises can increase motion and strength. This helps the patient get back up after surgery with faster recovery of function. It can also help minimize the risk of bleeding.

There are still problems with joint replacements for patients with hemophilia. Bleeding and infection are the biggest problems. There may be no improvement in motion.

Recovery of knee range of motion after ACL repair varies from patient to patient and doctor to doctor. Some of it depends on the type of repair you had. The rehab program can make a difference, too. Each doctor has his or her own expectations about knee motion after the operation.

Did the doctor tell you to expect the knee to be tight for months? You may want to bring your question up at the time of your next follow-up appointment. Full recovery of knee extension can occur within the first month. It usually takes longer (up to two months) to get full flexion back.

There is a special device that can be used to measure joint laxity or looseness. It measures how much the bones forming the knee joint slide against each other forward and back or side to side. This measure can be used to define “success” or “failure” after ACL. Recent studies suggest using five or more millimeters of joint glide as a failed ACL
graft.

About one-third of the 150,000 ACL injuries in the United States each year are repaired. That means two-thirds (the majority of patients) don’t have it fixed surgically. Those who don’t opt for surgery have trouble staying active in sports and activities.

You have several choices. You can do nothing, let it heal, and see what happens. There are some problems with this choice. Without some treatment, the joint may not be able to hold up under unexpected loads or sudden movements.

You can try a rehab program to restore motion after the injury. It may be worth your time to do some exercises prescribed by the physical therapist. This strengthens your knee and may help prevent future injuries. It takes at least six to eight weeks of time and effort to do this. If you don’t, you may be at risk for another (worse) injury later.

You can also talk to your doctor and let him or her know what you’re thinking. The operation and rehab program could be modified to meet your needs and goals.

Everyone agrees that ACL ligament repairs loosen up between six months and a year after the operation. It’s not clear yet just what causes it. Likewise, no one knows how to tell how much it will loosen up.

Researchers report different results of studies on this topic. ACL repairs in animals and humans have been done. Some report more tension applied during the operation means a tighter knee after. Other studies show grafts with less tension tighten up more later. Some doctors advise minimal tension put on ACL grafts give the best results.

It’s likely that joint tightness or looseness depends on many things. Graft tension is just one factor. The type of graft used, size of tunnel for the graft, and method used to hold the graft in place may be just as important. More studies are needed to find out the best graft tension and how to get it for each patient.

You’re right in your observations. Things have changed quite a bit from the 1980s and even from the 1990s to today. In the past, a more conservative approach to ACL rehab was the norm.

Patients were immobilized in a cast for sic to eight weeks. That was followed by crutches for another eight to 10 or 12 weeks. Today’s rehab is more “functional.” In other words: get them back on their feet doing everyday activities as soon as possible.

Motion right away and putting weight through the joint are the focus of rehab now. Proprioception training is also a key feature. Proprioception is the awareness of the joint, its position, and movement through its range of motion.

Closed-kinetic chain exercises are done with the foot or feet planted firmly on the ground or some other surface. This type of exercise is preferred because it helps reproduce normal, everyday movements.

Squatting, stepping, and stair climbing are examples of closed-kinetic chain activities. The exercises are functional but also reduce the strain and shear force on the ACL. In fact, they also decrease the compressive force on the patella (kneecap), too.

Yes! If your orthopedic surgeon hasn’t told you NOT to do it…you really should follow your therapist’s advice.

Studies show that exercise in the standing position after ACL repair is safe. This is true even during the early phases of rehab.

For example, during single-legged squats, the quadriceps muscle along the front of your thigh will contract at the same time as the hamstring muscles along the back of the thigh. This is called cocontraction.

With cocontraction there is very little shear force on the joint. Shear forces are normally generated when the quadriceps contract without the hamstrings. Activating the hamstrings decreases the amount of force that occurs when the quadriceps muscle contacts and pulls the tibia (lower leg bone) forward on the knee.

Your therapist will guide you through the rehab process with the right exercises at the right time. However, don’t be afraid to bring up your concerns. You need to feel confident that your knee will hold you up.

If the tendon graft is taken from the same leg, then only one leg is affected. The patient can shift the weight off that leg during the early days after the surgery.

Repairing the knee with donor tissue from the other leg means both sides are affected. There have been a few cases reported of problems developing from overload of the donor side.

This is more likely during the first 24-hours when the patient is still under the influence of anesthesia and drugs to limit pain. Without complete sensation, the patient can put too much load on the donor leg. The result can be an avulsion fracture. The remaining (weakened) patellar tendon pulls away from the bone.

On the plus side, taking donor tissue from the other leg leaves less trauma to the reconstructed knee. Rehab can progress along much faster.

Most surgeons use donor tissue from the same side. Talk to your surgeon about his or her preferences and reasons for choosing one over the other.

Not necessarily. It’s true that the longer a person waits, the greater the risk of the knee becoming unstable. Once the anterior cruciate ligament (ACL) is torn, there is greater strain on the other soft tissue structures in and around the knee.

Studies have shown that repair of ACL tears can be successful whether done right away or years later. If you’ve spent the last two years in rehab you may even have a better chance of good recovery. The exercises may have increased your strength. This can give you a “leg up” in recovery, so-to-speak.

We can help you understand some of the language used to describe your condition. To gain a better grasp of the actual pathology, it may be best to contact the radiologist directly. If you are under the care of an orthopedic surgeon, she or he can go over the MRIs and results with you as well.

As you probably already know, ACL refers to the anterior cruciate ligament. It’s one of two key ligaments inside the knee. ACL deficiency suggests the ACL is torn or injured and unable to perform its function.

Concomitant means “at the same time.” So along with the ACL tear, there are some other problems. Intra-articular means the trouble lies inside the joint. This could be the meniscus, bone, or capsule. Extra-articular would mean outside the joint.

Knee pain, swelling, and giving way two years after ACL repair are signs and symptoms that the joint is unstable. If you haven’t gone back to your orthopedic surgeon, now would be a good time to make an appointment.

It may be a simple case of muscular weakness or imbalance. Sometimes such problems can be taken care of with a rehab program. In other cases there may be other (unknown) damage to the joint. Perhaps there’s a torn meniscus or some osteoarthritis developing.

Worst-case scenario: the repaired ACL may have failed. Further testing is needed to find out what’s wrong. The chances are good that treatment is available that can get you back to the activities you like.

Flexion means “to bend” while contracture refers to the soft tissues being ‘fixed’ or ‘stuck.’ In more functional terms, a flexion contracture means your knee is flexed or bent and can’t straighten all the way.

When a joint stays in one position without moving for a long enough period of time, the tissues start to stick together. Fibrous tissue fills in between the soft tissue fibers. Loss of motion means the joint can no longer move the way it’s supposed to.

The usual result is pain and loss of function. It becomes harder and harder to climb stairs, get up and down off the floor, or even stand for long period of time.

Surgery to release or cut the contracted tissue is sometimes advised. More conservative treatment involves stretching and other exercises.