If you watch or play sports you have probably heard of meniscus injuries. Unfortunately,
they are very common knee injuries. They are most commonly seen in football, but
can happen in any sport.
What is a meniscus?
Each knee has two meniscus, one on the inside (medial) and one on the outside (lateral).
They are "C" shaped pieces of fibrocartilage that provide cushion between the tibia and
femur (at the knee joint). They are crucial in helping providing support to the articular
cartilage of the knee and limiting forces between the two leg bones. They help limit the
onset of arthritis in the knee.
One important thing to keep in mind when dealing with meniscus injuries is that they get
very poor blood flow. In general, cartilage in our body does not get good blood flow, so
this limits the ability for the meniscus to heal naturally.The only area that gets "decent"
blood flow is the outer 1/3rd of the menicus. For the inner 2/3rds, blood flow is minimal-none.
They call these zones the red zone (outer 1/3rd) and white zone (inner 2/3rds). Thus,
injuries to the white zone can be very difficult to heal and repair.
Causes of injury
Meniscus tears can happen traumatically such while playing sports or naturally over time.
As we age, the integrity of our tissues naturally decline over time. This can lead to
tears in the meniscus more easily. It can even happen from an everyday activity such as
going up and down stair,s or turning while walking.
Traumatic meniscus injuries often happen in a much younger population, usually when playing a sport. Strain is placed on the meniscus when the knee is fully flexed, extended, or with weightbearing (especially flexion/extension combined with weight bearing). The most common mechanism of injury is when there is a forceful twisting motion of your upper leg bone (femur) on your lower leg bone (tibia) when your leg is planted.
You will often see meniscus injuries coupled with other knee injuries such as torn ACL and
or MCL/LCL. This can commonly happen with a blow to the outside of the knee, resulting in a torn ACL, MCL and medial meniscus.
Types of tears
1. Intrasubstance/incomplete tears: these are considered normal as we change and may or
may not come with pain. These are usually early markers of degenerative changes in the
knee. Most times these do not require surgery.
2. Radial tear: these are the most common types of tears. They occur in the "white zone"
of the meniscus. Due to poor blood flow they have very poor ability to heal and often
require surgery. Surgery is usually performed by trimming and removing the damaged part of the meniscus.
3. Horizontal tear: as the name implies, this tear runs horizontally through the meniscus.
These can vary greatly in size and location. Typically they will respond best to surgery.
If the tear is in the "red zone" surgeons may be able to repair the tear.
4. Flap tear: the patterns of these tears will vary but they involve a portion of the
meniscus being peeled back. The portion that is peeled back will often get stuck in the
joint often causing catching of the knee. The good news with these tears is if it is painful,
surgeons can usually remove the flap while maintaining the integrity of the tissue.
5. Complex tear: these are very difficult to repair surgically. They involve multiple
types of tears such as radial and horizontal.
6. Bucket handle tear: these tears are large horizontal tears. Often the torn portion of the meniscus will block the knee’s normal motion and be very painful. Surgery is often
required for these cases to regain pain-free range of motion.
Diagnosis
There are a number of ways that a meniscus tear can be diagnosed. MDs and physical
therapists can use a number of tests that may reproduce your symptoms to determine if there is a tear.
If a tear is suspected the next step is usually an X-ray or an MRI. An X-ray will not
show a tear while an MRI will. Oftentimes, though, an X-ray is ordered first due to insurance requirements.
Symptoms of meniscus tear
- Pain at joint line (inside or outside of knee)
- Catching or locking of knee
- Stiffness
- Swelling
- Feeling like your knee buckles
- Difficulty with bending or straightening your knee, or pain with twisting/pivoting
- Difficulty performing normal activities
Depending on the patient’s symptoms, non-surgical treatment may be worth trying.
Non-surgical treatment
Initial treatment will include RICE: Rest, Ice, Compression and Elevation. You want
to reduce the swelling and pain as fast as possible. The next goal is to regain range of motion. From there, you will work on regaining strength and overall function. It is highly recommended that if you decide to manage your meniscus tear non-surgically, you should reach out to a physical therapist for assistance.
Surgical treatment
If surgery is the decided course of treatment, there are 3 surgeries they can perform:
1. Arthroscopy with debridement
2. Partial meniscectomy
3. Full repair
Arthroscopy with debridement: these are minor surgeries. The surgeon goes in and removes the part of the torn meniscus. The recovery time is quick with these and usually no crutches are needed. Most commonly you will be able to return to normal activities in a couple weeks.
Partial meniscectomy: Similar to the debridement, the surgeon will remove a larger part of the meniscus. These recoveries take a little longer. Depending on the surgeon you
may have some restrictions post-op. These may include limiting your weight bearing and range of motion for a couple weeks. Typical recovery time is 4-6 weeks.
Full repair is a much longer recovery process. Most patients come out requiring a knee
brace (locked in extension) and flexion is limited to 90 for 4-6 weeks. You will also
be non-weight bearing or partial weight bearing for 3-6 weeks (surgeon dependent). With these procedures, though, you get to keep your full meniscus intact once everything is healed.
I hope this helps answer some of your questions in regards to meniscus tears. Please let us know if you have any further questions.
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