Knee Cartilage Lesions


Both the femur (thigh bone) and tibia (shinbone) are covered with small, white, well-lubricated articular cartilage that makes the knee joint glide and function well. Healthy articular cartilage is a central component of a normal healthy joint.

Cartilage can become damaged due to a trauma such as a pivoting sport or when turning the knee or bending it deeply. Cartilage can also come loose due to damage in the underlying bone, OCD, or osteonecrosis. Sometimes cartilage damage occurs as part of degeneration, called osteoarthritis, which is the overall loss of tissue quality that occurs with aging.

Cartilage damage is most frequently seen between the ages of 15 and 30 or above the age of 50.

Damaged cartilage can lead to short-term symptoms such as pain, swelling, locking symptoms, and longer-term symptoms of osteoarthritis due to lack of the shock absorber function.

  • Cartilage defect. A cartilage defect can occur acutely when standing, turning, or pivoting during sport or as a result of trauma. This is usually followed by swelling of the knee and is aggravated by walking, standing, rising from a chair, or going up or down stairs. ┬áSometimes a cartilage fragment can’t come loose from the adjacent bone, which is most recognizable by a longer period of slight pain in the knee aggravated by an acute moment with locking and mechanical symptoms

A cartilage defect is characterized by:

  • Pain and tenderness. A cartilage defect causes diffuse pain in the whole knee, sometimes more specific in the damaged compartment, or pain more deeply located in the back of the knee
  • Locking. If a loose piece of cartilage gets stuck between the moving parts of the knee, the knee can be locked. This is a very acute phenomenon that occurs and disappears spontaneously. ┬áSometimes a loose piece can be felt floating around
  • Swelling. This occurs because damage to the articulating surface causes the knee to swell, which usually is related to the amount of loading

Consult your doctor if rest, ice, and over-the-counter pain relievers don’t ease your knee pain and when you have mechanical symptoms that prohibit you from normally bending and extending the knee because of locking symptoms. Seek immediate care if:

  • Your knee is hot and inflamed, and you have a fever
  • You can’t bend or extend your knee because of mechanical obstruction

A cartilage defect is difficult to diagnose based on the history and physical examination alone. Sometimes this diagnosis is mistakenly made as being a meniscus lesion and then MRI or arthroscopy shows a cartilage defect that can explain the clinical complaints.

An X-ray can help the doctor rule out other causes of knee pain, such as a fracture or arthritis. Cartilage does not show up on a standard X-ray. Sometimes bone changes under the cartilage defect can raise the suspicion of cartilage damage.

To properly visualize the cartilage, an MRI scan can be used and is frequently indicated in the younger patient. For older patients it is thought to be wise to be careful with ordering MRI investigations because they will show many more degenerative lesions that have no clinical implications and can worry and confuse some patients.

Treatment begins with avoiding activity that causes pain. Use crutches to offload the affected knee. Keep the knee moving to avoid stiffness and locking. To help relieve pain, use ice.


You can take an over-the-counter pain reliever. Try ibuprofen (Advil, Motrin IB, others), naproxen sodium (Aleve) or acetaminophen (Tylenol, others). Corticosteroid injections are not commonly given because they haven’t been shown to be effective long term in the treatment of cartilage damage.


Try the following:

  • Rest. Take rest and limit activities that aggravate the complaints. Try to unload or only partially load the knee until the pain is gone. If you have mechanical locking that prohibits normal motion of the knee joint, see a doctor.
  • Ice the affected area. Apply ice packs to your knee for 15 to 20 minutes at a time, three to four times a day for several days. To protect your skin, wrap the ice packs in a thin towel.
  • Use a brace. The use of a brace for meniscus damage is not often necessary, but sometimes it can be indicated if there is severe bow leggedness and pain on the inside due to overloading
  • Stretch and strengthen the affected area. Your doctor might suggest exercises for stretching and strengthening. Other physical or occupational therapy practices can be helpful, too.

Gradually return to your usual activities. When the above-mentioned therapy and medication alleviates your pain, there is no further need for treatment or additional diagnostic means. If complaints do not improve or mechanical symptoms occur, this can be a reason for another diagnosis or possibly surgical intervention.


Surgery can be a recommended option. If you are young and have an acute painful knee with mechanical obstruction that started with acute swelling after a rotation or valgus injury, this can be a reason to urgently see an orthopedic surgeon because either a meniscus tear, cartilage damage, or ligament instability can be the cause of these complaints. You may have a better outcome if diagnosed and treated earlier rather than later.

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