General Information About The Knee

  Anatomy of the Knee

The anatomy of the knee consists of bones, ligaments, cartilages and tendons.

The bones involved are the Femur (the thigh bone), the Tibia (the shinbone) and the patella (the knee cap). The ligaments involved are collateral and cruciate ligaments. Ligaments are another type of soft tissue. They hold the bones of the joint together.

Cartilage is a layer of smooth, soft tissue. It covers the ends of the thigh bone and shin bone, and it lines the underside of the kneecap. Healthy cartilage absorbs stress and allows the knee to glide easily without pain. Tendons attach the muscles to the bones.

The knee joint allows us to move indifferent ways. The movements are called extension, fiexion and rotation. A healthy knee bends easily because the joint absorbs stress and glides smoothly. This allows you to walk, squat and turn without pain. But when the knee is damaged, the joint may lose its ability to cushion stress. You may feel paint during movement or even when you are at rest. The knee is a hinge point formed where the thigh bone and shin bone meet. When the knee is healthy, the joint moves freely. This is because the joint is covered with slippery tissue and powered by large muscles.

  Diseases of Knee

  •   Malformations : (Varus) knee Knock - Kneed (Valgus) or Bow - Legged.
  •   Osteoarthritis.
  •    Secondary Osteoarthritis.
  •   Accidents - Resulting in injury to bone or joint parts.
  •   Osteoarthritis.

  Symptoms

  • Pain on walking, standing or on moving the joint.
  • Progressive reduction in the distance you can walk without pain.
  • Hardly any relief from pain even on resting & with pain killers.
  • Noises from the joint while moving them.
  • Difficulty in using stairs, toilet and getting up from floor or chair.
  • Sensation of locking of the knee joint.
  • Deformity of the knee joint.
  • Pain at night / rest or pain requiring regular pain killers Over time, wear and tear occurs due to poor alignment between Femur and Tibia on the medial side (Inside) or on the lateral side (Outside).

  Stages of Destruction

When one or more parts of the knee are damaged, joint movement suffers. Over time, cartilage starts to crack or wear away. Because cartilage cannot full repair itself, the damage may continue to increase. At first, your knee may just be a little stiff. But as the bones of the joint begin rubbing together, you're likely to feel pain. Years of normal use can cause cartilage to crack and wear away. The first stage of destruction by ar thritis involves the development of osteophytes (bone outgrowth). And over time, even walking causes these sharp osteophytes to reode the ligament, which can lead to complete destruction of the knee.

 

What's Involved in a Total Knee Replacement - TKR?

What is Total Knee Replacement?

In principle, Total Knee Replacement or TKR is the replacement of the diseased knee joint by an artificial implant. Many decades ago, the relatively simple structure of the knee joint - the condyle of femur and distal tibia - had inspired surgeons and medical technicians to create an artificial copy, and in the course of time, follow - up examinations and improvements in operative methods and materials have led to great progress, and the optimization of total knee prosthesis.

The knee prosthesis is designed to simulate the human anatomy to knee joint and is comprised of a femoral component, tibial base plate, polyethylene insert and patellar components.

The femoral component will fit in the condyle portion of femur bone; the tibial base plate will fit on the distal tibia, polyetheylene insert will act like the cartilages, the patella component will resemble the original patella. The femoral component will glide smoothly over the polyethylene insert, thus allowing you to walk, squat and turn without pain.

These components are made up, of metal, ceramic or polyethylene. All these materials have been specially developed for medical purpose with good tissue tolerance and allow the function to be as painless and lasting as possible.

Having your knee replaced?

Over the years your knee joint takes many stresses and strains during daily activities. When a disease process or injury to your knee occurs, the cartilage surface of the knee joint degenerate or wear out.

During total knee replacement surgery, the diseased and / or arthritic ends of the bones are removed. A metal component is secured to the femur and plastic components are attached to the tibia and patella. In this way, the smooth surfaces of the knee joint are restored, pain-free motion is again possible and it works as a normal knee joint.

For each implant type, there is a wide range of models manufactured in different sizes as the anatomy of the knee varies from one individual to another. The surgeon will prepare for the operation on your knee joint with a graphic plan compiled on the basis of X-rays and will thus determine the model, size and position of the implant parts.

What are artificial knee joints made up of ?

Material used for artificial joints are highly developed. They provide maximum tolerance and long-term acceptance by the human body, which is called bio-compatibility. Material development and fundamental know-how in metallurgy, material, research and testing. In general, there are two different types of material employed for orthopedic purposes Metals & Polymers (ultra high molecular weight polyelrylene).

When is Total Knee Replacement required?

  • Persistent pain in the joint recurring regular pain killers, affecting activities of daily living & compromising your quality of life.
  • When other treatments like medicines, plysiotherapyetc have failed and no other alternative treatment is likely to.
  • X-ray confirming advanced arthritic changes in the joint.
 

  Before Surgery - Getting yourself ready

Having decided to perform the total knee replacement surgery for you, various members of the staff will help you to prepare for the surgery as well as your recovery. At any time, if you have any doubts or require any clarification, please feel to call on your surgeon.

  • An anaesthetist will visit your for pre-operative examination and assessment, if it has not been done before.
  • An orthopaedic team will again visit you to give a final check and be available for any last minute questions.
  • Please make sure you inform about all the medicines you are taking at the moment for Hypertension, Diabetes etc. to the visiting Physician

  The Surgery

During the operation, the diseased knee joint will be replaced by an artificial implant. The intervention will be made through a skin section in a vertical mid-line incision on the surface of the muscles near the knee joint. The procedure of implanting an artificial knee joint is a routine operation. For this reason, possible complications should not be a cause of concern; rather, they should be seen as part of careful patient information. Total Knee Replacement surgery involves the removal of the diseased and / or arthritic ends of the femur and tibia and few cuts to shape the bones to fit the components. After these cuts are made, a metal component is secured to the femur and plastic components are secured to your tibia and to the back of your patella or knee cap. The knee is now moved through its range of movement to see if the total knee joint is stable. With everything secure, the soft tissues are sutured back together.

  Safety Precautions

  •   Do not soak in water until your physician approves, and your incision is completely healed.
  •   Continue to use your crutches or walker until your doctor tell you to stop.
  •   Continue to wear your white surgical stockings (TED hose) until your doctor tells you to stop.
  •   Follow the weight bearing guidelines giving by your doctor.
  •   Do not drive until your doctor approves.
  •   Do not jump or twist.
  •   Do not jerk or pull on anything.
  •   Do not run or jog.
  •   Notify your doctor or dentist that you have an artificial joint. This is important for any procedure for routine dental cleaning.
  •   Do not lift and carry anything over 15 to 20 pounds.
  •   Remove rugs and objects that are below knee level.

  Call Your Doctor If

  • You have any numbness or decreased motion of your foot or leg.
  • You have excessive pain, swelling or drainage.
  • The edges of your wound do not seem to be healing together.
  • You have a fever or any signs or symptoms of an infection.

  Physiotherapy

Physiotherapy is an essential port of your recovery following a total knee replacement.

  •   Physiotherapy aims to

    • Keep your chest clear.
    • Provide an exercise program to improve joint movement strength and flexibility.
    • Improves mobility and confidence with an appropriate walking aid.

    The Physiotherapist will initially review your at the orthopaedic clinic and assess your knee movement and strength. You will be provided with on appropriate walking aid and exercise program. Please practice both prior to your admission as this will assist your recovery. A list of exercises has been provided in this book.

    At the clinic, the Physiotherapist will discuss your recovery and progress goals following surgery. This goals are listed on the following page.

    A "CPM" (continuous passive motion) machine may be used following surgery to improve the flexibility of your knee. The use of this machine is dependent upon your surgeon's requirements.

      Goals Following Surgery

    The Physiotherapist will visit you daily to assist you to become independent, safe and confident with:

    •   Your walking aid.
    •   Bending your knee to 90ยบ.
    •   Negotiating stairs.
    •   Your exercise routine.

    Discharge from hospital depends upon these goals being achieved. This usually occurs between day 2 and day 4.