Knee anatomy

The knee is a modified hinge joint, similar to the hinge on a door. It moves backwards and forwards like a door hinge, and also as a complex rotational component that occurs when you flex or extend the knee.

Bones

Knee joints are composed of the femur (the long bone of the thigh) the tibia (shin bone) and the patella (knee cap).

Cartilage

The ends of the bones are lined with cartilage which acts as a cushion for the bones and provides shock absorbing function.

Ligaments and muscles

It is a major weight bearing joint, held together by ligaments, muscles and other soft tissue.

 

Knee Disease

The most common cause of pain and problems in the knee joint are two types of arthritis. Arthritis causes the cartilage to wear away causing the bones to run against each other without any lubrication or cushioning. When this happens, the bone becomes pitted, eroded and uneven, restricting movement and causing pain and stiffness.

Osteoarthritis

Osteoarthritis is a degenerative disease that most often occurs in patients over the age of 50, but can occur at any age if the knee joint has been damaged. Patients with osteoarthritis often develop bone spurs around the joint, which severely limit motion. It is also known as wear and tear arthritis, because the joint just wears out.

Symptoms
  1. Pain in the knee during weight bearing activities i.e. walking
  2. Limping to reduce the pain on the afflicted knee
  3. Loss of flexibility
  4. Pain which increases and eventually is present even when the patient is not doing weight bearing activities

 

Rheumatoid arthritis

Unlike osteoarthritis, which is a “wear-and-tear” cause of knee damage, rheumatoid arthritis is a chronic inflammatory condition that effects the joints and results in pain, swelling and stiffness. It can progress to the point where there is deterioration of multiple joint simultaneously, resulting in severe pain and loss of mobility. Although the exact cause of rheumatoid arthritis is not known, the onset of this disease most frequently occurs in middle-age and is most common among women.

Symptoms
  1. All the same symptoms as osteoarthritis
  2. Loss of appetite
  3. Fever
  4. Energy loss
  5. Anaemia
  6. Rheumatoid nodules (lumps of tissue under the skin)
  7. Flare-ups where multiple joints may be painful and stiff
Treatment

Non-surgical therapies can be instituted under medical guidance

  1. Weight loss helps to decrease the weight on the knee joint
  2. Avoiding activities that aggravate the condition and modification of exercise to low impact activities only
  3. Physiotherapist prescribed exercise to improve strength and flexibility of the knee
  4. Corticosteroids injections into the joint to reduce inflammation
  5. Joint fluid therapy – a series of injections directly into your knee designed to improve lubrication to the joint
  6. Non-steroidal anti-inflammatory drugs and/or nutritional supplements (chondroitin/glucosamine) may help to reduce the pain
  7. Bracing: to provide external stability to the knee
  8. Arthroscopic surgery – minimally invasive surgery to remove some of the debris or to repair torn cartilage
Surgery

If none of these treatments help, and the patient suffers from continually increasing pain and loss of motion, then knee replacement surgery might be the best available option.

Reasons of knee replacement surgery

Total knee replacement is considered only when all other conservative measures have failed and may be performed for the following reasons:

  1. Relieve pain
  2. To improve joint stability
  3. To improve alignment and correct bone deformity
  4. To improve quality of life