Anatomy of the Knee Joint
The knee is one of the most complex and largest joint in the body, and is more susceptible to injury. Meniscal tears are one among the common injuries to the knee joint. It can occur at any age, but are more common in athletes playing contact sports.
The meniscus is a small, "c" shaped piece of cartilage in the knee. Each knee consists of two menisci, medial meniscus on the inner aspect of the knee and the lateral meniscus on the outer aspect of the knee. The medial and lateral meniscus act as a cushion between the thighbone (femur) and shinbone (tibia). The meniscus has no direct blood supply and for that reason, when there is an injury to the meniscus, healing cannot take place. The meniscus acts like a "shock absorber" in the knee joint.
Causes of Meniscal Injuries
Meniscal tears often occur during sports. These tears are usually caused by twisting motion or over flexing of the knee joint. Athletes who play sports such as football, tennis and basketball are at a higher risk of developing meniscal tears. They often occur along with injuries to the anterior cruciate ligament, a ligament that crosses from the femur (thighbone) to the tibia (shinbone).
Symptoms of Meniscal Injuries
Various types of meniscal tears that can occur are longitudinal, bucket handle, flap, parrot -beak and mixed or complex.
The symptoms of a meniscal tear include:
- Knee pain when walking
- A "popping "or "clicking" may be felt at the time of injury
- Tenderness when pressing on the meniscus
- Swelling of the knee
- Limited motion of the knee joint
- Joint locking can occur if the torn cartilage gets caught between the femur and tibia preventing straightening of the knee.
Diagnosis of Meniscal Injuries
A careful medical history and a physical examination can help diagnose meniscal injury. The McMurray test is one of the important tests for diagnosing meniscal tears. During this test, your doctor will bend the knee, then straighten and rotate it in and out. This creates pressure on the torn meniscus. Pain or a click during this test may suggest a meniscal tear. Your doctor may order imaging tests such as knee joint X-ray and knee MRI to help confirm the diagnosis.
Treatment of Meniscal Injuries
The treatment depends on the pattern and location of the tear. If the meniscal tear is not severe, your child's doctor may begin with non-surgical treatments that may include:
- Rest: Avoid activities that may cause injury. Your child may need to use crutches temporarily to limit weight-bearing.
- Ice: Ice application to reduce swelling
- Pain medications: Non-steroidal anti-inflammatory drugs (NSAIDs) to help reduce swelling and pain
- Physical therapy : Physical therapy may be recommended for muscle and joint strengthening.
If the symptoms are persisting and conservative treatment fails, your child may need a knee arthroscopic surgery to repair the torn meniscus.
Surgical Treatment for Meniscal Injury
Knee arthroscopy is the commonly recommended surgical procedure for meniscal tears. The surgical treatment options include meniscus removal (meniscectomy), meniscus repair, and meniscus replacement. Surgery can be performed using arthroscopy where a tiny camera will be inserted through a tiny incision which enables the surgeon to view the inside of your knee on a large screen and through other tiny incisions, surgery will be performed. During meniscectomy, small instruments called shavers or scissors may be used to remove the torn meniscus. In arthroscopic meniscus repair the torn meniscus will be pinned or sutured depending on the extent of tear.
Meniscus replacement or transplantation involves replacement of a torn cartilage with the cartilage obtained from a donor or a cultured patch obtained from a laboratory. It is considered as a treatment option to relieve knee pain in patients who have undergone meniscectomy.