FAQ Category: Knee

Osteolysis is a term to define bone loss. It’s not uncommon after total knee replacements (TKRs). Bits of bone and debris from the back of the implant fleck off over time. The tibial plateau is referring to the lower leg implant. It’s more of a flat surface (hence the term ‘plateau’) compared to the round end of the femoral (thigh) side of the implant. The medial side is the inside edge of the joint.

Scientists are studying this problem. They are trying to reduce the amount of osteolysis. So far they’ve found three risk factors. These include polishing the back of the implant (where it joins the bone). The second is using a different method of sterilization. The one risk factor that can’t be changed is gender. Men are much more likely to have osteolysis after TKR compared to women.

With mild osteolysis you’ll want to keep making regular visits to your surgeon for follow-up. X-rays taken over time will help make sure you get further treatment when it’s needed sooner than later.

It does make sense and that’s what’s got doctors and scientists scratching their heads. Many studies of the spine and joints show changes where there is no pain and pain where there are no changes. They don’t know how to explain it.

It may be a little like that old question: if a tree falls in the forest but no one is there to hear it, does it make any sound? Are X-ray findings pathologic if the patient doesn’t have any symptoms?

It’s possible the changes will eventually cause symptoms. But it might take an injury or repetitive load to bring on any pain.

Doctors also suggest the joint’s ability to hold up under heavy or repetitive loads may be based on more than just joint alignment. Maybe if the patient doesn’t stress the joint past a certain point, there are no symptoms no matter what shape it’s in.

More study is needed to end the debate of when to treat a joint. Should we apply medical treatment any time there are symptoms (with or without X-ray changes)? Or should we apply treatment anytime there are X-ray changes with or without symptoms.

Some doctors would say your knee is unstable. The true definition of instability is when the kneecap called the patella dislocates or shifts too far to one side.

Symptoms of buckling, collapsing, or giving way are more often caused by weakness. The quadriceps muscle along the front of the thigh helps hold the knee straight. Flexion or bending the knee without warning is a sign of quadriceps insufficiency.

Such giving way or insufficiency occurs as a result of pain, deconditioning, or swelling inside the joint. When the doctor examines you he or she will try and decide if your symptoms are coming from outside or inside the joint. If the problem is outside the knee joint then is it caused by the patella or something else?

A complete diagnosis may require exam, X-rays, and even arthroscopic surgery.

Studies of hundreds of knee replacements show this can and does happen … even in patients with no risk factors or deformities. Ligament damage isn’t rare but it’s uncommon. It can happen to anyone but it does tend to occur in patients who are very overweight.

The surgeon usually repairs the surgically torn ligament. The surgeon may use an implant that is designed for use with a torn or absent ligament. Rotating-hinge knees are favored when the patient has severe joint instability. The doctor’s task is to balance the ligaments, stabilize the joint, and restore motion.

Not likely but you can ask. Sometimes orthopedic surgeons work with anesthesiologists who use acupuncture instead of anesthesia. Surgery is rarely done without an anesthesia and for good reasons. If the patient suddenly feels pain and jerks away, the surgeon’s knife or other tools can sever (cut) a nerve or blood vessel.

Some of the structures in and around the knee are very sensitive. Others are not. At least one surgeon mapped the sensitive structures of the knee without using an anesthetic. The doctor did this to himself. He probed his own knees without anesthesia.

He found that the fat pads were very sensitive tissue. So were the synovial tissues that protect the joint. The joint surface itself and the cartilage weren’t very sensitive. The bone just under the cartilage was very painful when overloaded. This happened most often when the cartilage was damaged.

All in all, even with a high tolerance for pain, it’s probably best to be numb when this operation is done. Too many things can go wrong when a patient isn’t anesthetized.

Acute compartment syndrome is a serious medical condition that occurs most often after a traumatic injury such as fracture, contusion, or burns. In the case of a burn the skin can’t stretch and flex for swelling underneath. It starts to act like the outside covering of a sausage.

There are serious consequences without proper treatment. The doctors may measure the compartment pressure several times before deciding on treatment. The measures will help them determine if the condition is getting better or worse. They may not take actual measurements but rather go on the basis of the history and clinical presentation.

Sometimes all that’s needed is proper positioning so the blood can flow to the area. For example, the leg should be kept down below the level of the heart. Movement and active contraction of the muscle is important to keep the fluids moving and prevent swelling.

If this doesn’t work, surgery may be needed. The surgeon may need to make a cut along the skin to release the pressure. Burn patients have some unique problems that require special consideration. The skin may need to be replaced with grafts. There’s always a concern for infection. Close monitoring is needed.

Any concern you have should be addressed. There are problems that can be caused by having a cast on that’s too tight. Acute Compartment Syndrome (ACS) is the most serious one. Rising pressure between the layers of bone, muscle, and fascia can cut off the blood supply to the leg.

Call your doctor and report any unusual symptoms. Pay attention to the temperature and color of the skin of the leg above the cast and in the foot or toes below the cast. They should be warm and pink or flesh-colored. Blue, black, or white are signs of blood loss.

Is your son complaining of numbness, tingling, or pain? Again, these are other symptoms of the cast being too tight.

Serious problems can be avoided by early detection and treatment. Trust your intuition and common sense.

Chances are your surgeon’s skill saved your leg and your life. Anterior compartment syndrome (ACS) is a serious condition. Left untreated you can end up with damaged muscles that never recover.

With all the pressure from the build-up of fluid, the blood supply to the muscles can get cut off. Infection and necrosis can mean amputation for some people. If the infection spreads through your blood supply, death is possible.

Anterior compartment syndrome (ACS) itself isn’t too rare. Most likely the location of the problem is what they were referring to. ACS is a sudden, large amount of swelling in an area where there isn’t enough room to hold all the fluid. ACS of the lower leg and forearm are most common. The thigh, buttock, arm, hand, shoulder, and foot can also be affected.

The other factor that may be considered “rare” is the fact that your daughter only had a single injury. Most cases of ACS occur after multiple injuries, burns, fractures, crush injuries, or bleeding disorders. Doctors are starting to report an increased number of cases of ACSC with contact sports with high-speed collisions such as football, ice hockey, and rugby.

A well-trained physician will recognize signs and symptoms of anterior compartment syndrome (ACS), which is a true medical emergency. Most doctors say that the exam is still the best way to make the diagnosis of this condition.

The classic signs of ACS are called the seven P’s and include:

Transplantation of chondrocytes (cartilage cells) is a three-part process that takes place over a period of weeks to months. The patient actually donates his or her own healthy cells.

Arthroscopic surgery is done to remove chondrocytes from a nonweightbearing portion of the knee joint. These are transferred to a lab where they are grown and multiplied outside the body. The lab process takes about three to six weeks.

When ready the cells are frozen and returned to the surgeon who prepares the surgical site and injects them into the cartilage/bone defect.

Autologous chondrocyte transplantation (ACT) is a fairly new treatment method for deep (full-thickness) cartilage tears. Studies have only gathered long-term results for about the last 10 years. Since these types of tears are most common with soccer and football players they are the ones studied most often.

The ideas are the same for tennis players who often have to make quick stops or sudden turns. It’s the mechanical load from movements like this that lead to cartilage injury or reinjury.

According to a recent study on high-level athletes returning to their sport, ACT worked best on younger players (less than 25 years old). The players who had other knee surgeries before ACT were less likely to have a good to excellent result.

Only 30 percent of the players who had ACT returned to their sport at their previous level. Eighty percent were the younger players with limited previous treatment. The ACT held up well under maximal mechanical forces imposed by frequent high-impact loads. Everyone was followed for at least one year. Some players still had good results up to four years later.

We’ll start with the bad news first. You may already know that without successful treatment your risk for knee osteoarthritis later in life goes up by a factor of five. This five-fold increase in risk is probably the result of high joint stress during the game. Soccer players are known for injuries because of frequent pivoting, rapid changes in speed, and collisions with other players.

The good news is that new treatment methods such as cartilage (chondrocyte) transplantation has made if possible for players to get back into the game. Those who return to competitive or high-level sports are able to return to their previous level of skill.

According to researchers the average time off is 18 months so it’s not a quick fix. But follow-up as much as nine years later showed that some players were still able to maintain their level of play.

Good question. We don’t have studies to show the long-term results of each possible treatment option. Some may say don’t worry about it — what will be, will be. Others say don’t borrow trouble before it happens. In other words, not everyone develops arthritis in a joint after a traumatic injury. The event increases your risk but doesn’t guarantee it.

You didn’t mention what treatment you’ve had for this problem now. Sometimes even young people damage the patella enough that fracture healing isn’t possible. In those cases, the kneecap may be removed, a procedure called a patellectomy. Older folks might opt for a total knee replacement, especially if they already have arthritis in the knee. Middle-aged patients may be given the choice of just a kneecap replacement.

The biggest factor in long-term results may have to do with your knee alignment. Does the patella track up and down well during knee motion? Is it balanced and in the center? Does it tend to track more to one side or the other?

The knee joint axis is also important. Are you slightly knock-kneed or bow-legged? These positions can affect how well the knee holds up over the years.

Ask your doctor for his or her recommendations. It could be there’s nothing to be done just now. Or there may be an exercise program that could correct any weaknesses or misalignments.

Decisions like this can be very difficult. It’s nice that patients have options and choices. Without knowing what can and will happen makes it a bit of a guessing game. Let’s look at each option.

Giving the bone time to heal can be a good choice. It’s non-invasive without the chance of surgical complications. However, if the person is a smoker, has a poor diet/nutrition, or other health issues, delayed healing can occur. Pain and stiffness may keep your mother from getting around during the six to eight weeks it will take to heal. Losing motion in an arthritic knee might cost her some function and independence. Under any of these circumstances it might be best to consider replacement.

At age 83 a patellar arthroplasty (kneecap replacement) will likely last the rest of her natural life. It won’t change the underlying arthritis in the joint but it will help keep her moving.

A recent long-term study of patients who had the kneecap replaced suggested older patients do better with a total knee replacement (TKR). With just the kneecap replacement, there are often revision operations needed. With the TKR motion is restored to the entire joint making it possible for the person to remain active.

Given all the factors to consider may help your mother decide what’s best for her health and lifestyle. If she tries the wait-and-see approach, she can always have an operation later. If she goes with the TKR her final recovery after rehab will be that much sooner.

There are at least half a dozen ways to go about repairing a defect in the cartilage-bone interface of the knee. Debridement is just one.

If you’ve had this tear for a long time and/or if it is a large tear, you may be a good candidate for a procedure called autologous chondrocyte implantation (ACI). The surgeon will remove some normal, healthy cartilage cells and grow them in a laboratory.

The cells reproduce until there are enough to reimplant into the knee. This stimulates cartilage healing and repair.

In a recent study comparing debridement to ACI, ACI came out ahead in long-term results. Patients reported more pain relief, greater reduction of swelling, and improved function.

Ask your surgeon about available options. See if ACI is a possibility.

Debridement is a term often used in the medical field when something is being removed. This could be skin, dead tissue around a wound, a bone lesion, or as in your wife’s case loose fragments of cartilage.

The surgeon will try to stitch down any flaps of cartilage. If that’s not possible the torn cartilage is carefully scraped away until there is just normal cartilage showing.

The operation is usually very successful in eliminating pain, swelling, and giving way of the knee. Most people have increased function as a result of these improvements.

Minimally invasive refers to several factors. A shorter operating time as you suggest is one measure. A shorter operation means less anesthesia. Sometimes there’s less blood loss. Those two things alone can also mean “less invasive” to the pocketbook.

According to a task force of surgeons there are several ways to tell if an operation is minimally invasive. First, the size of the incision is half the length of the standard approach.

Second the location of the cut is often different. The goal is to avoid disrupting the joint capsule or some of the muscles. If the capsule is cut, a smaller incision is used. Third, fewer muscles are cut or detached.

During knee surgery anytime the surgeon can avoid cutting the extensor mechanism, it’s considered “less invasive.” The extensor mechanism is made up of the quadriceps muscle as it comes down over the front of the thigh and attaches around the patella or kneecap.

Disrupting this muscle can cause weakness in knee extension. The patient may not be able to fully extend the knee, a condition called extensor lag.

There isn’t one single way to define minimally invasive but rather, a group of factors.

Surgeons are trying different ways to use the mini-incision for knee joint replacement. Reports are favorable for the mid-vastus approach. This is similar to the standard incision in the middle of the knee but smaller and slightly off-center.

The quadriceps muscle along the front of the thigh is made up of four major muscles. They work together to straighten the knee. The inside muscle group of the quadriceps is called the vastus medialis.

The surgeon splits the vastus medialis muscle in the direction of its fibers. The incision starts just above the patella (kneecap) and goes down to just below the patella.

A slightly different incision may be used for obese or very muscular patients. The surgeon still starts above the patella but curves the line around the edge of the kneecap rather than cutting straight down. The scar looks more like a question mark.

The new mini-incision method of joint replacement does indeed use a much smaller incision. The standard length opening is about eight to 10 inches. The mini-incision is about half that length at four to five inches.

The mini-incision does make it difficult for the surgeon to see everything. Special tools called retractors are used to gently pull back the skin and soft tissues.

Even so, the surgeon may not see the landmarks needed for the operation. Sometimes the guide used to cut out the old joint places the saw at a slight tilt. The implant may get put in with too much rotation resulting in poor alignment.

The mini-incision also makes it harder to remove loose bone fragments or extra cement that isn’t needed.

There are advantages to this method. Shorter operation time and fewer days in the hospital add up to money saved. Less blood loss and fewer pain drugs means the patient is up and moving sooner. With less trauma to the surrounding tissues, rehab is faster and easier.