FAQ Category: Knee

The surgeon will make every effort to get the infection under control and save the implant. If this doesn’t work then the implant may have to be removed. At this point treatment is still focused on clearing up the infection.

A revision surgery may be possible. After the implant is removed and the infection is under control, then a second implant may be inserted into the joint. If this is not possible, then a fusion may be needed.

With a fusion or knee arthrodesis, the patient can still put weight on that leg and walk but motion is very restricted. Getting in and out of a car or on and off a bus can be very difficult. Sometimes the surgeon has to shorten the leg so the patient can swing the leg through when walking.

Knee arthrodesis isn’t ideal but it does save the leg.

Treatment depends somewhat on your goals. If you are planning to return to competitive sports, then analgesics to control the pain and rehab may be your best options. However, you should be aware that without the meniscus, your knees are at increased risk for damage and changes from arthritis.

If possible, the meniscus is repaired rather than removed. Most patients are encouraged to put aside strenuous, high-impact activities to protect their joints.

For some younger patients, meniscal transplantation may be the answer. Cartilage freshly donated or stored in a frozen state may be used. The knee must be stable and in good alignment. There can’t be any bone spurs.

A surgeon will conduct a physical exam. How you stand and walk is evaluated. Knee joint motion and alignment are important. Too much angle at the knee may keep you from being a good candidate for this surgery.

This treatment option is only considered for younger patients (less than 40 years old). The down side is that long-term studies haven’t been done to show results 10, 20, or more years ater.

Talk with your doctor about what’s best for you given your age, activity level, and sporting goals.

Meniscal transplantation is a fairly new operation. Studies comparing the results using different rehab programs haven’t been reported. There’s no clear agreement on the best approach at this point.

In general you can expect some restrictions in motion and weight bearing until healing has taken place. This may take two to three months. Details of your rehab may vary depending on whether or not you have any other repairs done at the same time. Many patients with a torn meniscus also have a ruptured anterior cruciate ligament (ACL).

Motion is important after ACL repair to prevent scar tissue and adhesions from forming. Too much motion can disrupt the meniscal graft. Your doctor may prescribe a hinged knee brace for the first six weeks. The brace can be used to control how much weight and shear is put on the graft.

Patients can return to light work in about a week. Strenuous work can be resumed three to four months after the operation. Low-impact activities begin at eight weeks. Running is allowed after four to five months. Light sports are okay but high speed, high-impact activities are not allowed even after rehab is done.

Unicompartmental joint replacement is a good option for some patients. Not too much bone is removed so the patient can have a total joint replacement later if needed. It’s often the case that after the first side of the joint becomes arthritic, the other side eventually becomes diseased, too.

As with all operations, problems and complications are possible. In a recent long-term study, researchers noted that younger patients seem to have the best results with the unicompartmental implants. The device lasts longer and needs revision less often than in older patients.

Reasons for revision include disease progression to the other side of the joint or loosening of the implant. There’s no way to predict when or to whom this will happen. It’s just part of the risk of the procedure.

For the most part, studies show the unicompartmental implants work very well. The patients get pain relief. Motion is restored. They can start to walk again and do more things.

The McKeever hemiarthroplasty just replaces part of the joint surface. It’s a unicompartmental implant for the tibial (lower leg) side of the knee joint. The bottom half of the knee is divided into two compartments. The inner edge is called the medial compartment. The outer edge is the lateral compartment.

The McKeever implant can replace either the medial or the lateral unicompartment. Most often the medial joint is affected and replaced. The McKeever is a thin piece of metal designed to replace the fairly flat tibial shelf. The femur (end of the thigh bone) slides and glides over the tibial plateau during knee motion.

This type of implant has been around since the 1950s. It’s used mostly for patients who are too young, too active, or too heavy for a standard partial or complete joint replacement.

There are many possible causes of continued knee pain after joint replacement. The plan to do revision surgery suggests the surgeon thinks the problem is coming from the knee or the implant itself.

Sometimes the implant isn’t in the best position and the knee biomechanics are off. Pain, swelling, and stiffness can occur. There may be instability at the knee. Tension in the soft tissues such as muscles and ligaments must be carefully balanced during the operation. Failure to do so can lead to pain from pinching of the soft tissues or giving way of the knee.

In other cases too much scar tissue forms and the joint starts to lose motion. The result is usually pain and stiffness. The implant can also loosen, get infected, or even fracture causing similar problems.

Ask the surgeon for an explanation of what’s wrong and what is the treatment plan. If your mother has had a painful knee for years she may need some extra rehab to restore muscle strength and motion. An exercise program is often a good idea before and after revision surgery.

Hamstring muscle weakness after ACL repair has been reported in studies done comparing one type of ACL graft to another. The hamstring tendon graft doesn’t appear to cause any problems with function during daily activities.

Other researchers report decreased stability after surgery for patients with the hamstring tendon graft. It’s thought that the way the graft is fixed to the bone may be part of the problem. In many cases the end of the tendon is attached outside of the joint rather than inside the knee. This may put it at a biomechanical disadvantage for movement and strength.

More studies are needed looking at the long-term effects of the tendon grafts used in ACL repairs. Function, strength, and motion should be compared between groups of athletes versus non-athletes.

Anterior cruciate ligament injuries are often just one of several injuries to the knee. Often the meniscus is torn at the same time. If this is the case the surgeon usually does repair everything at the same time.

In some cases a minor meniscal tear may be present. The surgeon tries to repair these types of injuries rather than remove the cartilage. Long-term studies have clearly shown the benefit of keeping your cartilage as long as possible.

Meniscal tears occurring after ACL reconstruction are fairly common. Several studies show a high reoperation rate for this problem. As many as one-third of all patients develop symptoms of meniscal problems following the ACL repair.

The use of multistrand hamstring tendon grafts and now hamstring tendon grafts with a bone plug to repair a ruptured anterior cruciate ligament (ACL) is gaining popularity.

Many studies have been done comparing the patellar tendon graft to the hamstring tendon graft. The results have been very favorable towards the hamstring tendon graft. Although the preparation of the graft takes longer, the stability of the knee afterwards may be worth it.

Patients have fewer problems at the donor site with the hamstring tendon graft. The patellar tendon graft is taken from the front of the knee causing painful kneeling afterwards. Sometimes the pain is severe. In most cases it never goes away.

Rehab is the same for both graft types. Recovery is not reported to be faster with one graft over another. Complications can occur with either method causing a delay in recovery. If no problems occur after the operation you should be back on your feet in two to four weeks. Full recovery and return to preinjury activities take longer (four to six months).

The cause of osteochondritis dissecans (OCD) remains unknown. It’s not clear if it is inherited though there seem to be some family ties such as in your family. Scientists call this familial predisposition.

A few studies have shown limited evidence to support the idea of a genetic pattern. Most of the people affected were first generation (father, sibling, or brother) rather than second-degree relatives such as a nephew.

Most of the time there isn’t any obvious family or inherited link. OCD does tend to occur more often with some other inherited conditions. These include dwarfism, Legg-Calvé-Perthes disease, and Stickler’s syndrome.

Right now scientists suspect OCD is a multifactorial problem. Genetics may play a part in that but nothing has been clearly proven just yet.

Osteochondritis dissecans (OCD) is a problem affecting the joint with softening and detachment of the cartilage and bone. It affects boys twice as often as girls. The highest rates seem to occur among boys between the ages of 10 and 15 years.

It’s hard to predict what will happen with this disease. Doctors would say it has a “guarded prognosis.” Skeletal maturity at the time of diagnosis is the best predictor of outcome. The younger the patient, the better the chances for bone healing and recovery. Nonsurgical treatment is more likely to work for this group compared with older (adult) patients.

Patients with a stable joint have a better chance for a good outcome. With a stable joint there may be a fragment of damaged bone and cartilage, but it has not torn away from the joint surface. Smaller lesions do better than large ones. Damage to the weight-bearing surface of the joint is less likely to recover with nonsurgical treatment.

There’s a large wait-and-see component to this condition. There’s no way to say for sure he’ll be back on the team next year. Encourage him to follow his doctor’s advice carefully. This can help ensure his successful return to the team.

Unicompartmental arthritis is not uncommon in some younger patients. Many have had the meniscus removed from a previous injury and now years later, arthritis has badly damaged the joint. Pain, stiffness, and loss of motion and function are common.

Joint replacement isn’t a good option yet for young adults. Too much bone loss and an implant that only lasts 10 to 15 years makes another replacement difficult. It is possible to have a unicompartmental replacement.

This is an attractive option for middle-aged patients. It only removes and replaces the portion of the joint that’s arthritic. Most of the bone is spared making it possible to have a total joint replacement later.

Ask your surgeon if you might be a good candidate for this procedure. You may also want to consider looking into gastric bypass surgery. If weight loss isn’t possible, it may be a way to lose weight and protect your joints from future deterioration. Talk to your doctor about your total health picture and find out what all your options are.

Total knee replacement (TKR) is usually a very reliable way to give arthritis patients relief from their symptoms. About 95 percent of all TKR patients have a good result after surgery. But in five percent problems of pain, stiffness, and swelling can persist.

There are many possible causes for this outcome. If your father hasn’t been to his doctor, a re-examination is important. The surgeon will conduct a careful evaluation to see if the problem is coming from inside or outside the joint.

Many older adults have multiple health problems. These are called comorbid conditions. Neurologic problems, poor circulation, even depression are just a few comorbidities that can affect the results of surgery.

A medical differential diagnosis always begins with the patient history. Details of your health, symptoms, and function give the doctor clues to what is going on. Comparing symptoms from before the knee replacement to now can also be helpful.

Infection doesn’t happen very often but it must always be considered first. Early treatment is very important to avoid future problems. Pain that doesn’t go away, swelling, and redness are signs and symptoms of infection. Wound drainage or failure to heal are also indicators.

There are several tests that can also aid in the diagnosis. If there is wound drainage the area can be tested for local infection. Fluid from inside the joint can also be removed and tested. Lab work such as blood tests can measure your white blood cells for signs of infection.

The kneecap or patella sits over the knee joint and moves up and down along a track of cartilage. Connective tissue on each side called the retinaculum help hold it in place and guide it up and down in the track.

Patellar instability occurs when one side of the retinaculum is tighter or looser than the other. The kneecap can move out of the track and sublux or even dislocate. When this happens over and over the patella doesn’t always go back to the middle. One edge hangs over the side (as seen on X-ray).

Conservative care with physical therapy, exercises, and bracing or taping is the usual treatment. If these measures don’t help after three months then surgery to rebalance the retinaculum may be considered.

Patellar (kneecap) instability is a fairly common problem for some athletes. Treatment using heat or thermal energy with radiofrequency has been used to shrink soft tissues in the shoulder. A recent study reported results with the application of heat to the knee called thermal reefing.

Everyone who had this treatment had at least three (sometimes more) lateral dislocations. All were in a physical therapy program for at least three months but continued to have dislocations before the heat treatment was used.

The thermal reefing was done along with a lateral release. The retinaculum, a band of connective tissue along the outside edge of the patella was cut. Putting the thermal reefing along with retinaculum release helped realign the kneecap.

This treatment may not work as well with increasing age. It seems the amount of shrinkage decreases as we get older. There are fewer heat-sensitive bonds between the tissues. There are also complications of the heat treatment such as damage to nearby nerves, cartilage, or bone.

If you aren’t having any dislocations right now, you would be best advised to try a rehab program first. Building up the muscles and balancing the motion of the kneecap will benefit you now and through the aging process.

The normal kneecap (patella) moves up and down over the knee as we bend as straighten the leg. It follows a track of cartilage and bone as it glides and slides with knee flexion and extension.

A band of tissue called the retinaculum along either side of the patella help keep it in the center. If the retinaculum is too tight or too loose on one side or the other, then the patella can get pulled too far to one side (usually to the outside or lateral edge). It can be serious enough to cause subluxation or even dislocation. And it can dislocate over and over causing pain and loss of function.

The physical therapist will show you how to tape the patella to keep it tracking in the middle. You will be given supervised exercises as well as a home program to follow. The idea is to strengthen the quadriceps muscle to the knee to help realign the patella. The goal is to have a normal resting position for the patella and normal tracking during movement.

The therapist will make sure the other muscles around the knee (like the hamstrings behind the knee) are also in balance. And the PT will help you “retune” your knee. Sometimes after injury the joint doesn’t always know where it is as it is moving. This can contribute to some motor control problems and add to the mix.

You should allow at least three months of consistent rehab before evaluating your results. If you are making steady improvement, you will want to continue and/or progress the program.

Surgeons want to know the answer to this question, too. So studies have been done trying to link characteristics of patients who had a failed result. They’ve looked at age, size of tear, and how long between the injury and the repair.

Some studies show a better healing rate when the tear is small and repaired quickly. Others don’t show the same results. Most studies have not been able to show any significant factors in meniscal healing.

The one exception is the patient who tore the meniscus and the anterior cruciate ligament. Repairing both at the same time seems to help meniscal healing. This is probably because there’s more bleeding and clots forming. This seems to help meniscal healing.

For the moment you are indeed part of a small number of people who didn’t get the results they hoped for or expected.

Of course every surgeon has his or her own protocol and timeline for patients. Some of this is personal preference and some comes from where the surgeon trained. The type of surgery done can make a difference too.

Patients who have the meniscus and the anterior cruciate ligament repaired at the same time may have a slightly different course to follow. You may be wearing a hinged brace to limit motion a little. This helps prevent disruption of the sutures during the early phase of healing.

Most patients wear the brace and use crutches or a cane for the first three weeks, putting partial weight on the foot and leg. By the end of six weeks you’ll be moving the knee to 90 degrees of flexion and putting your full weight on it.

Jogging (not running) comes around weeks 10 to 12. By six months you’ll be back to full activity. Remember, you must follow your doctor’s instructions. If what he or she tells you is different than what we report as the typical pattern, you must abide by the surgeon’s orders!

A very good question. First of all, only a piece of the hamstring tendon is removed. At least half or more of the tendon is left intact. The postharvest strength of the graft tendon must be strong enough for early rehab and daily activities.

If the graft doesn’t hold it usually pulls away from the bone with a little piece of bone attached. This is called bone avulsion.

Before these grafts were ever used on patients, scientists used animal and cadaver studies to test the strength of the tendons before and after grafting. This is how they know which tendons will hold up after a piece is removed for use as a graft.

They also found that ACL tensile strength decreased over 50 percent between age 20 and 50. This isn’t true of the patellar tendon. During this same time period, tensile strength of the patellar tendon doesn’t change. That makes the patellar tendon a good graft choice.