Meniscus Tears (Pediatric)
What are meniscus tears?
The meniscus is the tissue that cushions and stabilizes the femur (thigh bone) as it moves on the tibia (shin bone). It is made from thick cartilage (fibrocartilage), which provides durability and forms a C-shape on the medial (inner) side of the knee and a more circular shape on the lateral (outer) side.
Acute meniscus tears result from a twisting injury while playing sports. These tears can occur in different places in the meniscus and have different tear patterns. They can also occur many times in conjunction with a tear of the anterior cruciate ligament (ACL)—the lateral (outer) side with acute ACL injuries and the medial (inner) side with chronic ACL tears.
Discoid meniscus is a congenital anatomic variant seen almost exclusively on the lateral (outer) side of the knee. This results in a thickened meniscus that covers more of the lateral tibia (shin bone) than a normal meniscus. There are three different kinds of discoid meniscus susceptible to tearing. It should be noted that an asymptomatic discoid meniscus requires no treatment.
The function of the meniscus is well understood. It is important in load sharing, shock absorption, and stability. Multiple biomechanical studies have shown the protective effects of a functional meniscus. A torn meniscus treated with menisectomy (partial removal) has increased risk for the development of early osteoarthritis.
Who is affected by meniscus tears?
Once a rare diagnosis in pediatric and adolescent athletes, a torn meniscus is now commonly recognized. This condition is seen in athletes playing sports such as football, soccer, basketball, and hockey. Meniscus tears impede the knee's function and range from minor to severe depending on the extent of damage.
What are the symptoms of meniscus tears?
- Knee swelling
- Popping sound with knee motion
- Tenderness around joint line
- Knee “locks up” or gets stuck
- Unable to completely straighten knee
- Knee pain with activity
- Difficulty with stairs and getting up from a seated position
After a meniscus tear, patients are able to walk and put weight down. Some athletes even try to play through the injury. However, continued play causes inflammation in the knee. Large tears may flip over and get stuck, causing a locked knee.
How are meniscus tears diagnosed?
Our doctors perform a thorough physical examination focusing on the knee's movement and areas of tenderness. X-rays help to exclude other knee injuries and an MRI (magnetic resonance imaging) of the inside of the knee often confirms the presence of a meniscus tear.
What is the treatment for acute traumatic meniscus tears?
Treatment for meniscus tears focuses on controlling pain and inflammation. Initial management of meniscus tears involves the common approach in sports medicine of RICE: Rest, Ice, Compression, and Elevation of the affected leg. If needed, pain medication can also be prescribed. Crutches can be used to move around.
Management of meniscus tears depends on location and size of the tears and also for how long they've been present. Small tears on the periphery with good blood supply may require nothing more than rest to heal. Other tears do not have the same potential to heal on their own and require surgery.
If surgery is needed, our goal is to preserve as much of the meniscus as possible. Every attempt will be made to fix the meniscus. Some tears, however, are not repairable and parts of the torn meniscus will be trimmed back to a stable base.
What is the treatment for discoid meniscus tears?
Many of the same principles apply for tears involving the discoid meniscus. When tears are symptomatic and causing pain, locking, or feelings of instability, surgery can be needed. However, some of the surgical strategies differ from the acute non-discoid meniscus tears as we aim to reshape or “saucerize” the meniscus.
What happens after meniscus surgery?
Your child will start physical therapy to decrease swelling and strengthen the quadriceps. If the meniscus is repaired, we recommend 4-6 weeks of toe-touch weight bearing with crutches. Some repairs may limit the motion allowed from 0-90 degrees for 3-4 weeks.
If the meniscus is trimmed (partial menisectomy), weight bearing is allowed immediately and a return to activity is dictated by recovery and strengthening of the quadriceps muscle
The good news is many growing athletes are able to recover and return to previous activities after most meniscus tears in a few months.