A knee replacement may be total or partial, or may occur when a previously implanted artificial joint has failed or been damaged. Conditions like arthritis are often what cause enough pain and lack of mobility to require that a person get a new, artificial knee. Although surgery is always risky, a knee replacement can restore mobility and relieve significant pain.

While many people have successful knee replacement surgeries, and the artificial joints have improved and become more durable over the years, some people suffer debilitating complications. When this happens, the patient may need numerous revision surgeries. Some companies making artificial knees have produced faulty components and systems that led to high rates of revision surgeries and complications.

Reasons for Knee Replacement Surgery

For many people receiving an artificial knee or artificial components, the surgery is risky but well worth it. Conditions like osteoarthritis, rheumatoid arthritis, bone cancer, and osteonecrosis can cause significant damage to knee joints over the years. This damage may result in a lot of pain and a lack of mobility. A new knee joint can restore that mobility and relieve pain. When the symptoms of damage are severe enough or interfere significantly with daily life, a doctor may suggest a knee replacement.

Types of Knee Replacement

A total knee replacement is done for patients with extensive damage throughout the entire joint. The whole joint is replaced with an artificial knee system. If the damage is less extensive, a patient may only need a partial replacement. One or more components of the joint may be removed and replaced with an artificial piece. Partial replacements are usually less invasive and require less recovery time.

A patient may need a revision surgery, or multiple revisions, if an artificial knee joint or component fails. The revision is done to correct any damage or to replace a failed part. Revisions may also be done to treat infections or inflammation in the joint, if the joint becomes dislocated, or if it comes loose in the knee.

Complications and Risks

All surgeries come with risks and potential complications. There may be a bad reaction to anesthesia, and there is always the risk of infection and blood clots. Some knee surgeries can be done with minimally invasive techniques, and these are less risky. Other surgeries are major, require larger incisions and longer surgical times and carry more risk.

Complications that may occur and are specific to knee replacements include deep infections within the joint, fractures in the leg bones that occur during surgery, a difference in the lengths of the legs after the surgery, and even a decrease in mobility and motion in the knee joint after the artificial components have been implanted. After surgery, sometimes a year or more after, the joint may shift, dislocate, loosen, or sink into the surrounding bone or tissue.

Artificial Knees

The knee joint forms where the femur meets the tibia. The femur is the bone in the thigh and the tibia is in the lower leg. Where the two come together, a small bone called the patella sits in front, and several ligaments connect the bones to each other to create a joint that is flexible.

Many medical device companies make artificial knee joints and individual components. They may be made from plastic, metal, or ceramics, but all are made of three basic parts: the femoral component attaches to the femur or thigh bone; the patellar component replaces the kneecap; and the tibial component is the part that attaches to the tibia. Ligaments that attach the bones to one another may be left in the joint, but for some people these become damaged and must be removed. In the latter instance, artificial knee takes over the role of connecting the components of the joint.

Artificial knees may have a fixed bearing, which results in less mobility or a mobile bearing, which allows for more rotation. A mobile-bearing knee joint may have a medial pivot, which gives the joint most of its natural movements, or a rotating platform, which offers greater flexibility.

Problematic Artificial Knees

Some of the knees made by medical device companies have caused serious complications or have failed early and have caused patients to have revision surgeries. DePuy, for example, a division of Johnson & Johnson and one of the biggest manufacturers of artificial knees, has faced a number of recalls of its high-tech high flexion knees. These are supposed to provide a superior range of motion, but studies have not been conclusive that they are any better than other knees. Also, these knees have caused more bone loss and revisions.

Zimmer has faced recalls as well, over components that did not work correctly. Also recalled were Smith & Nephew knee systems that caused loosening, pain, and revision surgeries and others that contained too much iron. Stryker has had to recall knees over high revision rates, and Biomet has recalled both knees and knee surgical instruments over mislabeling, incorrect size information, and incorrect assembly. Stryker has also faced problems with manufacturing, receiving warning letters from the FDA about quality control issues in two factories making knee joints.

Lawsuits

Many people who suffered after receiving an artificial knee have sued the companies who made the faulty joints. There are always risks with these surgeries, but when the components are faulty, the risks are higher and patients may suffer pain, further immobility, and a need for more revision surgeries. Zimmer is one company that faced such lawsuits and had to pay settlement fees. In 2003, Zimmer paid out $1 billion in settlements because a defective knee implant caused problems for patients.

If you have suffered because of a knee replacement, you have legal options. You have the right to sue the manufacturer if you believe that company was at fault for providing you with a knee system that failed or caused unnecessary complications. Having extra revision surgeries is time-consuming, painful, and increases the odds of having more complications. If you believe you are entitled to compensation, contact a lawyer to find out what your options are.