The knee plays an important role in your mobility, but this common injury can lead to a host of symptoms, including swelling and pain.
Perhaps you feel a telltale “pop” while playing sports. Or maybe you feel your knee giving way as you do something as simple as getting up from a chair. And although you may still be able to walk, your knee is swollen and may be causing pain.
If any of these symptoms sound familiar, you might have injured a part of the knee called the meniscus. Known as a meniscus tear, this injury is fairly common and can impact people from all ages and walks of life, including professional athletes, weekend warriors and everyone in between.
What is a meniscus?
The meniscus is a C-shaped piece of cartilage that serves as a shock absorber between the bones that comprise the knee joint, including the femur (thigh bone) and tibia (shin bone). There are two menisci in each knee, and they help protect the knee joint when you move, as well as keep you steady on your feet. Because it is instrumental to proper knee function, if the meniscus is injured it can impact a person’s mobility.
“Meniscal tears are one of the most common injuries treated by sports medicine doctors,” explains Frank Petrigliano, MD, chief of the USC Epstein Family Center for Sports Medicine at Keck Medicine of USC and associate professor of clinical orthopedic surgery at the Keck School of Medicine of USC.
How do you tear your meniscus, and who’s at risk?
Anyone can tear their meniscus, but people who play sports and older adults are more at risk for this type of injury — although for different reasons.
According to Dr. Petrigliano, there are two types of meniscal tears:
- Acute tears — More common in young or highly active people, these injuries can be caused by a traumatic event, such as twisting, or a blow to the knee. Acute tears can sometimes be accompanied by injuries to other structures in the knee, such as the ligaments or cartilage.
- Degenerative tears — These types of tears occur more commonly in older people and are more often associated with wear and tear of the knee joint. “These injuries may be seen in knees that have some early arthritis, which weakens the cartilage of the knee and makes it more prone to tearing,” he adds.
How do you know if you tore your meniscus?
Hearing a “pop” sound from the knee is often associated with a sign of a torn meniscus.
According to Dr. Petrigliano, symptoms may also include:
- Pain and swelling — Meniscal tears often result in knee pain that is concentrated on either the inner or outer portion of the knee, depending on the location of the tear in the meniscus. These tears can also cause swelling of the knee.
- Problems moving the knee — In some cases, a torn meniscus may cause mechanical symptoms, such as locking or catching of the knee, or a sensation of giving way. “In severe cases, a portion of the meniscus may flip into the joint, resulting in a ‘locked knee,’ which is essentially an inability to completely extend the leg,” he explains.
Does a torn meniscus need surgery?
In order to diagnose what type of meniscal tear you have, your doctor will perform a physical exam, along with imaging tests. Although surgery is one of the treatment options, it’s not always recommended.
For degenerative tears, physical therapy and anti-inflammatory medication or, occasionally, an injection are the treatments of choice, according to Petrigliano.
“Most degenerative tears are associated with mild early cartilage wear in the knee,” he says. “In these cases, surgical treatment may not offer a solution, because it cannot remedy the underlying wear to the cartilage.”
Acute tears, however, may require a different treatment approach, depending on the size and location of the injury.
“For most acute tears, surgical management is recommended, particularly for active people,” Petrigliano says. “Small tears may be treated with a partial arthroscopic meniscectomy, a procedure that removes a small portion of the meniscus to alleviate mechanical symptoms and pain. Larger tears require more complex repair.”
Rest, ice, compression and elevation, also known as RICE, may be recommended as part of your treatment plan.
What is the recovery time for a torn meniscus?
The recovery time for a torn meniscus depends on several factors, including the size and location of the injury and whether or not surgery and physical therapy are required.
“The recovery following partial meniscectomy is rapid, with most patients returning to activity within six to eight weeks following the procedure, with appropriate physical therapy,” Petrigliano says. “For more complex cases, the recovery may be up to six months to allow the meniscus to heal and restore strength and range of motion of the knee joint.”