Patients with knee arthritis may find it hard to perform simple activities, such as walking or climbing stairs and feel pain while sitting or lying down. The different parts of the knee work in harmony. But disease and injury can disturb this harmony, causing pain, muscle weakness, and reduced function of the knees.
Obesity may lead to osteoarthritis by putting more stresses on the cartilage and is considered the most important risk factor for osteoarthritis of the knee. Repeated trauma to the knee is believed to lead to early osteoarthritis in athletes. Some people are born with abnormally formed joints causing early degeneration and loss of joint cartilage. Generally speaking, the most common causes of knee arthritis are:
- Osteoarthritis. This is an age-related "wear and tear” of the knee. The cartilage that cushions the bones of the knee softens and wears away. The bones then rub against one another, causing knee pain and stiffness. It usually occurs in people 50 years of age and older, but may occur in younger people, too.
- Rheumatoid arthritis is termed "inflammatory arthritis." This chronic inflammation can damage the cartilage causing cartilage loss, pain, and stiffness.
- Post-traumatic arthritis. This can follow a serious knee injury e.g fractures causing knee pain and limiting its function.
Total knee replacement surgery is a solution for arthritis pain if medications are no longer helpful. A total knee replacement is a surgical procedure whereby the damaged surface of the knee joint is replaced with artificial material.
There are several reasons why knee replacement surgery is recommended:
- Severe knee pain or stiffness that limits your everyday activities like walking, climbing stairs, and getting in and out of chairs.
- Moderate or severe knee pain while resting, either day or night
- Chronic knee inflammation and swelling that does not improve with rest or medications
- Knee deformity — a bowing in or out of your knee
- Failure to improve with other treatments such as anti-inflammatory medications, cortisone injections, and/or physical therapy.
Candidates for Surgery:
Recommendations for surgery are based on a patient's pain and disability, not age. Most patients who undergo total knee replacement are age 50 to 80
Before the surgery
The surgeon will ask for your medical history to assess your general health and a physical examination will be done to assess knee motion, stability, strength, and overall leg alignment.
- X-rays are also needed to help determine the extent of damage and deformity in your knee.
- Other tests: Occasionally blood tests, or advanced imaging such as a magnetic resonance imaging (MRI) scan, may be needed to determine the condition of the bone and soft tissues of your knee.
The 4 basic steps to a knee replacement procedure are :
- Preparing the bone. The damaged cartilage surfaces are removed.
- Positioning the metal implants. The removed cartilage and bone is replaced with metal components that recreate the surface of the joint.
- Resurfacing the patella. The kneecap is resurfaced with a plastic button.
- Inserting a spacer. A medical-grade plastic spacer is inserted between the metal components to create a smooth gliding surface.
After the surgery
Your orthopedic surgeon will explain the potential complications of total knee replacement surgery; both during and after the surgery. This is so the patient does not have unrealistic expectations of the result of the surgery. It must be understood that the replacement surgery will not allow you to do more than you did before you developed arthritis.
Surgeons advise against high-impact activities such as running to avoid wear of the plastic spacer and to increase the durability of the artificial knee. Otherwise the patient can do low impact activities such as walking, swimming, driving and biking.
The complication rate following total knee replacement itself is low but as with any surgical procedure, complications can occur. Some possible complications are:
- Blood clots: Blood clots in the leg veins are the most common complication of knee replacement surgery. The patient must elevate his legs periodically, do lower leg exercises to increase circulation , wear support stockings. In addition the patient is give certain drugs to prevent this complication.
- Neurovascular injury: While rare, injury to the nerves or blood vessels around the knee can occur during surgery.
- Infection: Few patients, 1 %, get a knee joint infection. It may happen while in the hospital or after you go home . Minor infections are generally cured with antibiotics. Deep infections may require surgical intervention.
Patients usually go home 3 days after the operation. it is important to keep the surgical area clean and dry so until it has thoroughly sealed do not soak the wound in water. You may want to to bandage the wound to prevent irritation from clothing. The stitches itself will be taken off several weeks after surgery
A balanced diet is important to help your wound heal and to restore muscle strength. The patient must avoid weight gain.
The patient can resume normal daily activities within 3 to 6 weeks following surgery. Some pain with activity and at night is common for several weeks after surgery. The doctor will tell you to do exercises several times a day to restore movement and strengthen your knee.