Dr. Thomas Beck is the Orthopedic Surgeon at the Richland Hospital. This story was created not to diagnose you, but rather to help you to better understand the nature of joint disorders and what we can do to treat your symptoms.
Knee Anatomy
The knee is a hinge joint. The bones of the knee are the femur, tibia, and patella. The end of the femur contains two rounded protrusions called condyles. These condyles can be compared to the rockers on a rocking chair. They contact the top of the tibia and provide a smooth rocking and gliding motion. The tibia, or shinbone, provides a stable platform for the condyles. Condyles also help distribute the weight of the upper body. The patella, or kneecap, is the triangular bone at the front of the knee. Its job is to help the thigh muscles provide movement to the lower leg. The bones in the knee are held together with ligaments, which are strong bands of tissue that connect bone to bone.
The surfaces of the bones in every joint are covered with a cushioning and lubricating tissue called cartilage. Cartilage provides a very slick surface so the bones in the joint can freely move against each other. This cartilage is known as articular cartilage since it provides smooth, pain-free motion to the bones.
Arthritis
Arthritis is inflammation of the joint and refers to more than 100 different diseases that can affect the joints. The two most common forms of arthritis are rheumatoid arthritis and osteoarthritis.
· Rheumatoid arthritis is an inflammatory condition, and it is usually diagnosed at much younger ages than osteoarthritis. Excess fluid builds pressure inside the joint and causes the inflamed tissue to attach to the joint cartilage, leading to cartilage erosion. The end result of rheumatoid arthritis can be painful, swollen joints and limited joint movement.
· Osteoarthritis, or degenerative joint disease, is the most common form of arthritis. It affects 23 million people in America every year. Osteoarthritis is a wear and tear condition that affects joint cartilage and develops over a lifetime of overuse, injury, repetitive movement, or developmental disorders of the bones. The degenerative effects of osteoarthritis can lead to pain, stiffness, changes in leg length, and bone-on-bone contact.
Signs and Symptoms
The signs and symptoms of arthritis include joints that are warm to the touch, swollen, painful and immobile. Arthritis can affect the legs by causing bow-legged or knock-kneed deformities. Arthritis of the knee can cause a person to limp or favor the affected leg. But the most intolerable symptom is pain, and pain is the symptom that all physicians attempt to reduce or eliminate.
Conservative Treatments for Arthritis
Some of the most beneficial treatments include lifestyle changes, which include everyday things you can do to take a proactive approach to control your joint pain. Although some treatments may not assist the affected joint at this time, changes can improve the health of your other joints.
· A well-balanced diet coupled with regular doctor prescribed low-impact exercise can help reduce excess body weight, decrease pressure on the joints, and increase joint strength. For example, the weight load placed across the knee can reach up to four and a half times your body weight. This means that a 150-pound person can place up to 675 pounds of pressure on the knee. Even small decreases in excess body weight can help alleviate pressure on the joints.
· Medications can help relieve both joint swelling and pain.
· Support braces can be used to help straighten the leg and reduce the amount of pressure on the knee.
· Walking aids, such as a walker or cane, can also assist with relieving the amount of pressure placed on painful knee joints.
· Rest and ice can be used when you notice an increase in symptoms, especially after activity.
· Physical therapy may be used to help strengthen joints and promote less painful function. Weak or tight muscles provide little support and can make it difficult to move the joint. Physical therapy can help loosen and strengthen muscles, possibly providing relief from joint pain.
When to Consider Joint Replacement
So, when should you consider total joint replacement? It may be time to consider joint replacement when conservative treatments fail to provide adequate relief from pain and limited movement and when you experience a diminished quality of life. The benefits of total joint replacement can include decreased pain, increased joint movement, and an improved quality of life. The technique of total joint replacement, also called arthroplasty, uses implants to resurface and replace damaged bone and joint cartilage. The procedure is designed to reduce or eliminate pain while restoring the joint’s mobility. Total joint implants are typically made from a metal alloy such as titanium or cobalt chromium and polyethylene, a durable plastic.
During knee replacement, the femoral component caps the end of the femur, or thighbone, and the tibial component caps the top of the tibia, or shinbone. The tibial component consists of a metal tray that supports an polyethylene plastic component. The polyethylene provides smooth movement for the femoral component. The tibial component can also restore proper alignment in the joint to help you regain a more normal walk and stance. Sometimes the back of the patella is also resurfaced with a polyethylene button.
Signature™ Personalized Patient Care
The Signature™ system utilizes custom femoral and tibial positioning guides developed from MRI. The advantage of using MRI is that, unlike an X-ray, it creates a detailed three-dimensional image of your unique anatomy that enables the surgeon to preoperatively plan your knee replacement.
Typically, I use X-rays to size the implant components before surgery. During the knee replacement procedure an assortment of instruments are used to verify component sizing and establish proper positioning and alignment.
With the MRI and Signature™ personalized positioning guides, I have access to a greater level of detail and precision for implant position and alignment before the procedure. This allows for personalized implant positioning and may help enhance surgical efficiency. You can expect the MRI scan to take approximately 20 minutes. The scan will only be performed on your hip, knee and ankle, so your head will remain outside of the machine.
I use the MRI is for preoperative planning. It is also used for the design and manufacture of the Signature™ personalized positioning guides that will be used during your knee replacement.
Surgery
The surgical procedure using the Signature™ personalized positioning guides is similar to traditional total knee replacement with a few exceptions. During traditional total knee surgery, multiple instruments are used to position the guides for removing damaged bone and cartilage. Traditional total knee replacement sometimes uses instruments placed inside the femur (thighbone) and/or tibia (shinbone) to assist with implant alignment and positioning.
Signature™ personalized positioning guides are placed directly onto your femur and tibia. These custom guides will assist me as I place pins that will secure the metal cut blocks. The metal cut blocks will guide the saw as it removes the thin layer of damaged bone and cartilage.
Benefits
The Signature™ personalized positioning guides enable me to position a reduced number of instruments during surgery to carry out the preoperative plan. Additionally, the procedure does not require instrumentation of the bone canal, allowing for a potentially less invasive procedure, reduced risk of infection, potentially shorter surgery time, and improved implant placement precision.
If you have questions and you would like to talk to me about this new system, give me a call at 608-647-6161.
