The knee is a major weight-bearing joint of the lower limb. Structurally, it is a relatively complicated joint, adapted for movement, support and stability of the body. Injuries of the knee are relatively common.

Predisposing factors:  A number of factors can predispose people to knee problems:

  • Obesity: Excessive weight bearing increases the probability of injury or degeneration.
  • Overuse. Ongoing repetitive activity or exercise, particularly with poor technique or footwear.
  • Previous injury of the joint may heal with some scarring, instability or misalignment, which may create problems later.
  • Compensating. An injury or deformity in a joint of the leg or in the spine may cause a person to compensate for pain or imbalance by developing an abnormal gait (way of walking). This increases the risk of developing knee or ankle problems.
  • Chronic conditions like rheumatoid arthritis, gout and lupus.

Anatomy. The knee is a hinge joint formed by the junction of three bones – the femur (thigh bone), the tibia (shin bone), and the patella (kneecap). The femur and tibia are separated by two spongy disks (menisci), and strongly held together by the collateral ligaments on the sides and the cruciate ligaments within the joint. The quadriceps muscle (thigh) connects via the quadriceps tendon to the patella which in turn is joined to the tibia by the patellar tendon. The ends of the bones and the back of the patella are covered by smooth cartilage.

Common knee problems

Cartilage Injuries and Disorders

  • Chondromalacia (or chondromalacia patellae) is a softening of the articular cartilage on the back of the patella, caused by rubbing against the lower femur. It may be caused by trauma, overuse, muscle weakness, or excessive inward rolling of the foot (pronation). This causes a dull pain around or under the kneecap that worsens when the knee bears weight as it is straightened (like when walking down stairs). It is common in runners (runner’s knee) and is also seen in cyclists and soccer players. Treatment
  • Meniscus injuries occur when the knee is rotated while bearing weight (like turning to hit a tennis ball), leading to a tear in the tissue of the meniscus. This gives rise to pain, particularly when the knee is straightened, and later, swelling. After the injury the knee may click, lock, or feel weak. Treatment

Osteoarthritis of the Knee

This is a degenerative (wear and tear) disease where joint cartilage gradually wears away, causing pain, swelling, and a decrease in motion. A common symptom is morning stiffness that lessens after activity. Sometimes the knee joint locks or clicks on bending or straightening. Treatment

Ligament Injuries

  • Cruciate Ligaments. The anterior cruciate ligament is usually injured by a sudden twisting motion. The posterior cruciate is usually injured by direct impact. Cruciate ligament injuries may not always cause pain – a “popping” sound and buckling of the leg on weight-bearing may be experienced. Treatment
  • Collateral Ligaments. These are most often caused by a blow to the side of the knee that stretches and tears the ligament on the opposite side of the knee, which may buckle sideways, with pain and swelling. The knee joint may become unstable. Minor tears often heal within 2 – 4 weeks with a prescribed exercise programme. Ice packs may help to reduce initial pain and swelling, and a knee brace can help to stabilise the knee. A severely torn collateral ligament usually requires surgical repair.

Tendon Injuries and Disorders

  • Patellar Tendonitis (jumper’s knee) is caused by straining of the patellar tendon due to the muscle contraction and force of hitting the ground after a jump. The tendon may become inflamed or tear after repeated stress. Treatment
  • Osgood-Schlatter Disease is caused by repetitive stress (like frequent running and jumping) on the growth area (apophysis) of the upper tibia, at the point where the patellar tendon attaches. It commonly occurs in active children between 10 and 15 years old, and is characterised by pain and inflammation of the patellar tendon and surrounding soft tissues. Treatment
  • Iliotibial Band Syndrome (ITB) is an inflammatory condition caused by friction (rubbing) of a band of a tendon over the outer bone (lateral condyle) of the knee. It is usually caused by the stress of long-term overuse, like long distance running, and manifests as an ache or burning sensation at the side of the knee during activity. Swelling is usually absent and knee motion is normal. Treatment

This article should give you a fair sense of the most common knee problems seen today, what causes them, and how they are treated.