Knee Replacement Surgery
Arthritis or traumatic injury to the knee can cause pain, deformity and stiffness that can severely limit daily activities. Knee replacement can alleviate that pain and restore the normal alignment of the knee, allowing you to move easily.
Not everyone is a candidate for knee replacement. Discuss the pros and cons of your different treatment options with your physician.
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Types of Knee Replacement
Total Knee Replacement
If the cartilage damage in your knee has occurred on both sides of the joint, or in all three joint components, a total knee replacement procedure may be performed. During the surgery, the damaged part of the knee joint is removed from the surface of the bones, and the surfaces are then shaped to hold a metal or plastic artificial joint. The artificial joint may be attached to the thigh bone, shin, and knee cap either with cement or special bonding material. When fit together, the attached artificial parts for the joint, relying on the surrounding muscles and ligaments for support and function.
Houston knee replacement surgery relieves pain in more than 90 percent of patients. Within months of surgery, most patients can play golf, drive a car or go for a long walk.
Partial Knee Replacement
Sometimes, the cartilage damage in your knee is limited to one or two surfaces. When this happens, a partial knee resurfacing (PKR) procedure may be more appropriate.
Knee Replacement Locations
Knee replacement Houston is available at a Memorial Hermann Joint Center near you. See locations.
Am I a Candidate for Knee Replacement Surgery?
Millions of Americans suffer from chronic joint pain and a loss of mobility that brings challenges to the simplest daily routines. Knee replacements are a fairly common solution and one of the most reliable treatments in any area of medicine. For the right patient, they can be a game-changer.
Your orthopedic surgeon will decide if you are a candidate for the surgery based on your medical history, a physical exam and x-rays. Your orthopedic surgeon will ask you to decide if your discomfort, stiffness and disability justify undergoing surgery. There is usually no harm in waiting if conservative, non-operative methods are controlling your discomfort.
Talk to your physician about knee replacement surgery if you can answer yes to any of these questions:
- Are you having knee pain that keeps you awake, or awakens you at night?
- Are your normal, daily activities limited (walking, lifting yourself up, climbing stairs, etc.)?
- Do you have knee pain that limits activities such as walking for exercise, traveling or shopping?
- Have you tried other treatments for a reasonable period of time and you still have persistent knee pain?
The National Institutes of Health has concluded that knee replacement surgery is a safe and cost-effective treatment for alleviating pain and restoring function in patients who do not respond to conservative measures. In general, significant restoration of function and reduction of pain occurs in 90 percent to 95 percent of those undergoing knee replacement surgery. In some cases, partial knee replacements can be performed. In most cases, however, a total knee replacement is necessary.
At the Memorial Hermann Joint Center, patients learn which option is best for them – a new prescription, joint injection, physical therapy or minimally invasive joint replacement surgery.
Knee Replacement Technology
At Memorial Hermann, patients have access to leading technologies in knee replacement, including MAKOplasty®, Computer Assisted Navigation, and custom fit knee implants.
MAKOplasty is performed using RIO®, the Robotic Arm Interactive Orthopedic System. RIO provides three-dimensional modeling to help your surgeon plan your procedure, and it gives the surgeon real-time feedback during surgery to ensure accurate implant placement and alignment. MAKOplasty partial knee replacement is the ideal solution for patients with arthritis in only one or two compartments of the knee. Total knee replacements, once thought to be the only option, are no longer the only choice for many patients. During this procedure, the diseased part of the knee is resurfaced, sparing the healthy bone and surrounding tissue. The surgeon places the implant in the joint to allow the knee to move normally again.
- Smaller incisions
- Healthy bone and tissue preserved
ACL Sparing Knee Replacement®
ACL Sparing Knee Replacement® is the first and only knee replacement surgery available that allows for the posterior cruciate ligament (PCL) and anterior cruciate ligament (ACL) to be preserved.
Most total knee replacements require surgeons to remove the ACL, which is crucial to knee movement and stability, even when it’s still healthy. For patients that are active and have a healthy ACL, this surgery will enable the ligaments to function normally.
Computer-assisted surgery, also known as Navigation, utilizes advanced technology that provides valuable information about the joint and the patient’s anatomy to the surgeon. The surgeon is able to pre-plan the surgery using CT images and Navigation software to determine the most accurate implant placement. The results are improved alignment and orientation of the implant and greater range of motion, stability and mobility, thus causing less wear and tear on the implant.
Custom Fit Implants
Custom Fit implants are patient-specific implants that are made to fit the unique shape of your knee. These implants are made possible due to advanced CT and MRI technology. This technology converts CT/MRI data into implants that are designed to conform to the unique 3D structure of your joint.
The design process begins when you receive a diagnostic scan as prescribed by your surgeon. We then map the surface contours of your joint in the areas affected by osteoarthritis. This information facilitates the creation of an implant that is designed to precisely match your individual knee anatomy.
- Implant matched to individual size and shape
- Natural, anatomic feel and alignment
- Significant bone preservation
- Less trauma to the knee during surgery
- Faster recovery time
Quad-sparing total knee replacement is a minimally invasive surgery done through a small incision. Patients who have quad-sparing total knee replacement typically have quicker recovery, less pain, and a smaller incision so the scar isn’t as visible. People in the Houston area are fortunate to have this option for knee replacements available so close to home.
A traditional knee replacement is done through an incision 8 to 12 inches long. In order to reach the joint, the surgeon cuts through the quadriceps tendon (the main tendon of the muscle above the knee).
In a quad-sparing total knee replacement, the incision is 3 to 4 inches. Special instruments allow the surgeon to go through the side of the knee. The surgeon doesn’t cut through the tendon or violate the muscles. This technique spares the quadriceps tendon.
Cutting the quadriceps tendon causes weakness for quite a long time, but with quad-sparing surgery, the weakness is absent, so patients are walking and returning to normal activities in a much shorter time. Two weeks after surgery, most patients are walking using only a cane, and most people are back to a normal lifestyle within six weeks.
Possible Complications of Knee Replacement Surgery
Joint replacement surgery is major surgery and although advances in technology and medical care have made the procedure very safe and effective, there are risks.
These risks should be considered carefully before you decide to have surgery. We encourage you to discuss the potential risks with your orthopedic surgeon, primary care provider and your family.
Every measure will be taken by our team of experts to minimize the risks and avoid complications. Although complications are rare, they do sometimes occur. We will do our very best to avoid the most common risks which include:
Blood clots are more common in older patients, patients who are obese, patients with a history of blood clots, patients who smoke, and patients with cancer.
Infection is very rare in healthy patients having a knee replacement. Patients with chronic health conditions, like diabetes or liver disease, or patients who take some forms of corticosteroids, are at higher risk of infection after any surgery.
Nerve, Blood Vessel, and Ligament Injuries
Damage to the surrounding structures in the knee, including nerves, blood vessels and ligaments, are possible but extremely rare.
Sometimes the surgical incision heals slowly, particularly if you take corticosteroids or have a disease that affects the immune system, such as rheumatoid arthritis or diabetes, or you are a smoker.
Limited Range of Motion
Within a day of surgery, you will begin exercises to help improve the flexibility of your knee. Your ability to bend your knee after surgery often depends on how far you could bend it before surgery. Even after physical therapy and an extended recovery period, some people are not able to bend their knee far enough to do normal activities such as reaching your feet to put on socks or tie your shoes.
Bleeding into the knee can occur either immediately after surgery or at a later time. This is accompanied by acute pain and swelling and is sometimes confused with infection.
After surgery, the knee may feel a bit unstable. This will normally improve as muscles regain their strength.
Loosening of the Joint: Over the long term, loosening of the artificial knee joint is the most common risk associated with total knee replacement. Loosening may occur when tissue grows between the artificial joint and your bone.
Recovery from Knee Replacement Surgery
Most patients with artificial joints are able to enjoy many activities, though some should be avoided. Regular exercise to restore your knee mobility and strength and a gradual return to everyday activities are important for your full recovery. A home program for rehabilitation exercises is a MUST during the early recovery period. Your surgeon and therapist will determine the type and amount of exercise you should be doing to assist you in returning to your normal, active lifestyle. Early motion is the key to a successful recovery.
Patients encourage each other and share their joint replacement experience in a group setting, from preoperative education to postoperative rehabilitation.
What to Expect
Your physical therapist will provide you with a packet that is designed specifically for you prior to discharge. For maximum benefit, the program should be followed according to the instructions provided. You may feel uncomfortable at first, but these exercises will speed your recovery and actually diminish your postoperative pain.
During weeks 1 through 3, you will become more independent. If you are receiving home therapy, you will need to be very faithful to your exercise program to achieve the best outcome.
During weeks 4 through 6, you will see increasing mobility and will become more independent. Your home exercise program will be even more important as you receive less supervised therapy.
Weeks 7 – 12
During weeks 7 through 12, you should be able to begin resuming all of your normal activities.
Knee Replacement Revisions or Replacements
All implants have a limited life expectancy depending on an individual's age, weight, activity level and medical condition. A total joint implant's longevity will vary in every patient. It is important to remember that an implant is a medical device subject to wear that may lead to mechanical failure. While it is important to follow all of your surgeon's recommendations after surgery, there is no guarantee that your particular implant will last for any specific length of time.
Despite the success of these procedures, about ten percent of implants will stop working resulting in a revision surgery to remove the current implants and replace them with new components.
Causes of Surgery Revision
The decision to perform a revision joint replacement is based on several factors. The joint may become painful or swollen, due to implant loosening, material wear, or infection. Function of the implant may deteriorate over time in conjunction with these issues.
The most common reason for revision is loosening of the artificial surface from the bone. Wearing of the plastic spacer may also result in the need for a new spacer.
Reasons for implant failure include:
- Implant loosening
- Patient specific issues: Younger, active patients have a higher rate of revision surgery. Obese patients have a higher risk of wear and implant loosening.
A fusion, also known as an arthrodesis may be used as an alternative to revision surgery. This procedure generally used in situations where an infection cannot be eradicated.