What is the Meniscus?
The meniscus are two C-shaped pieces of rubbery cartilage in the knee that fit between the femur (thigh bone) and tibia (shine bone). The meniscus act as shock absorbers and bumpers inside the knee joint. They allow the knee joint to glide smoothly and distribute the forces within the knee during activities such as walking, running, and jumping.
Meniscus Tear Causes and Symptoms
Meniscus tears come in many different shapes and sizes, and they can occur for a variety of reasons. Often times they occur as a result of a specific trauma such as landing awkwardly from a jump or being tackled in football. Other tears occur over time as a result of degeneration (wearing out) of the cartilage. In general, there are five common types of tears –flap, radial, vertical, bucket-handle, and degenerative. Each type has its own set of causes and treatment options.
In cases of traumatic tears, the patient often experiences an acute popping sensation in the knee followed by pain and swelling. In cases of degenerative tears, patients will sometimes experience the slow onset of symptoms. When a meniscus tear is symptomatic, a patient may experience pain, swelling, and/or mechanical symptoms (clicking, catching, and/or locking of the knee).
It is important to understand that each patient is different and the symptoms listed above do not always mean you have a meniscus tear. A diagnosis should be made by an orthopedic surgeon to ensure the injury is treated appropriately.
Diagnosis and Examination
Diagnosis is based on the patient history, physical exam, and imaging (such as X-rays and/or MRI). A meniscus tear can often be diagnosed on physical exam. The McMurray test is used to detect a tear of the meniscus, and will often cause pain and clicking when performed. Additional exam findings include swelling, pain with range of motion, and joint line tenderness.
In most cases, x-rays of the knee will appear normal. If there is a concern about a meniscus tear or other knee injury, an MRI is usually performed. An MRI can be used to determine the size and shape of a tear as well as, look for other knee injuries such as cartilage or ligament tears.
Types of Meniscus Tears
The meniscus is a C-shaped structure that sits inside the knee joint. There are different types of meniscus tears and the type of tear can usually be determined with a knee MRI. Described here are 5 common types of meniscus tears.
- Radial Tear: Radial tears of the meniscus are the most common. These appear as small tears in the inner part of the meniscus. These tears occur in the avascular part of the meniscus (where there is no blood supply) and, as a result, have little ability to heal on their own.
- Flap Tear: Flap tears of the meniscus (sometimes known as a parrot beak tears) also usually occur in the avascular portion of the meniscus. They can often cause mechanical symptoms such as catching and locking since they can flip in and out of position.
- Vertical Tear: Vertical tears of the meniscus (sometimes known as longitudinal tears) are tears that develop along the circular curve of the meniscus tissue. When these tears get large enough, they can sometimes displace into the front of the knee and are then known as bucket-handle tears.
- Bucket-Handle Tear: When vertical tears of the meniscus become large enough, they can sometimes displace (like the handle of a bucket) into the front of knee. This can result in a “locked knee,” where the patient can’t full straighten the knee joint. Bucket-handle tears usually require an urgent surgical evaluation.
- Degenerative Tear: Degenerative meniscus tears (sometimes known as horizontal or complex tears) tend to develop over time as a result of “wear and tear,” and is often associated with knee osteoarthritis (loss of the smooth cartilage that coats the ends of our bones). These types of tears will usually not heal on their own given the poor blood supply to the meniscus as we get older, but they can often can be managed successfully without surgery.
Non-Surgical Treatment for Meniscus Tears
Surgery is not required in all patients with a meniscus tear. Your surgeon will take into consideration the tear type, as well as your specific lifestyle needs when determine the best treatment option. Non-operative treatment often includes a period of rest followed by a course of physical therapy. This allows the patient to build strength in the muscles surrounding the knee joint, allowing for normal knee function with activities. Nonsteroidal anti-inflammatory drugs (NSAIDs) may also be helpful in reducing pain and swelling. Lastly, some patients benefit from a corticosteroid injection into the knee. Corticosteroid is a strong anti-inflammatory and can often relive knee symptoms associated with a torn meniscus.
Surgical Treatment for Meniscus Tears
The majority of meniscus tears cannot scar in and heal on their own as a result of poor blood supply to the inner parts of the meniscus tissue. As a result, some patients continue to have symptoms that interfere with their desired activities despite initial non-operative treatment. In these situations, surgery is usually recommended.
Meniscus surgery is usually performed through several small incisions around the knee and with the use of an arthroscope (a special camera to look in and around the knee joint). Surgery is approximately 1 hour in length and is usually performed as an outpatient procedure in an ambulatory surgery center (ASC).
Some meniscus tears are able to be repaired by the surgeon with several small stitches. In some situations, the torn meniscus cannot be repaired and, as a result, the surgeon debrides and trims away the torn meniscus tissue to prevent further damage to the knee joint. Whether or not a repair is performed depends on the meniscus tear pattern, size, and location, but children and young adults have a higher rate of repair than other age groups. The decision whether to repair or debride a meniscus, is ultimately made at the time of surgery depending on the tear pattern, size, and location.
There are potential complications with any surgical procedure. With meniscus surgery, some of the potential complications include knee stiffness, re-tear of the meniscus, and infection. In order to minimize the risk of these complications, your surgeon will give you antibiotics during the procedure (to minimize risk of infection) and you will begin formal physical therapy within 1-2 weeks of surgery (to minimize the risk of stiffness and/or re-tear). Fortunately, these complications are rare, but when they do occur, additional surgery can sometimes be required.
Meniscus surgery is usually about one hour in length and is usually performed as an outpatient procedure in an ambulatory surgery center (ASC). Following surgery, patients are given specific instructions in order to ensure the best possible outcome. This includes a small prescription of pain medications and specific instructions regarding activity and wound care. Your surgeon may also have you use crutches and a knee brace for a period of time following surgery, depending on whether a repair or debridement was performed. In most cases, patients will participate in formal physical therapy to help rehabilitate the knee. Following a meniscus surgery, patients are able to return to sports between six and 12 weeks following surgery, although this may vary depending on the specific surgery performed.
Overall, the outcomes of meniscus surgery are excellent. With the appropriate physical therapy and rehabilitation, patients can expect to return to their normal pre-injury activity level. Unrestricted return to sports such as skiing, soccer, football, and basketball usually occurs between 6 and 12 weeks following surgery.
Why Choose ROC?
Your best chance at having an excellent outcome following a meniscus injury is to have things done right the first time. It’s important to have the correct diagnosis, receive the appropriate treatment, and rehabilitate the knee, all in a timely manner. At Reno Orthopedic Center, we have fellowship-trained sports medicine surgeons who focus on treating knee injuries. Our Sports Medicine Team has the training, experience, and expertise to treat your knee injury and get you back to the activities you love.