Torn Meniscus-torn knee cartilage not limited to athletes or sports.
Edited By: Carol C. Teitz, M.D.
Last updated Wednesday, January 12, 2005
Torn Meniscus - The menisci are pads between the femur and the tibia Torn Meniscus - Types of Meniscal Tears Torn Meniscus - Extreme bending can tear a meniscus Torn Meniscus - The McMurray Maneuver Torn Meniscus - A meniscal tear as seen on MRI Torn Meniscus - A tear in the non-vascular region of the meniscus as seen through the arthroscope Torn Meniscus - A probe is inserted in the tear, immediately adjacent to the meniscal blood supply AboutBasics of torn meniscus-torn knee cartilage The knee is made up of the femur (thigh bone) and the tibia ( leg
bone) which are held together by ligaments, and the patella (knee cap)
which lies in the Quadriceps muscle in the front of the knee.
Between the femur and the tibia are two pads, one on the medial
(inner) side of the knee and one on the lateral (outer) side of the
knee. Each of these pads is called a meniscus.
The meniscus is made of fibrocartilage which gives it a rubbery
texture. However within the meniscus there are also fibers of collagen
that help maintain the shape of the meniscus. The meniscus has blood
supply only at its outer attachments. Therefore, about 4/5 of a
meniscus has no blood supply and therefore cannot heal a tear.
The meniscus functions to improve the fit between the femur and the
tibia, to absorb shock and distribute load in the knee, and to help
move lubricating fluid around the knee.
The meniscus can tear either from trauma or from degeneration. Immediate medical attention A torn meniscus needs immediate attention
when it "locks" the knee. A knee is locked when it will neither
completely bend or completely straighten because something is caught
inside. Locking implies that the torn part of the meniscus has
displaced into a part of the knee where it doesn't belong or fit.
Facts and myths Some people think that only athletes can tear a meniscus. This is not
true. Even people who do not consider themselves "athletes" can tear a
meniscus. Some menisci (plural) tear during activities of daily living
such as getting in and out of a car or squatting. Menisci also tear
during participation in recreational activities such as skiing ,
dancing, or racquetball.Prognosis A torn meniscus is certainly not life threatening and once treated, the knee will usually function normally for many years.
A meniscal tear that catches, locks the knee, or produces swelling on a frequent or chronic basis should be removed
or repaired before it damages the articular (gliding) cartilage in the
knee. A meniscal tear that produces discomfort but does not produce any
of the symptoms mentioned above may be less likely to damage the rest
of the knee. One may choose to "live" with this type of meniscal tear
instead of treating it operatively.
Pain A torn meniscus usually produces well localized pain in the knee. The
pain often is worse during twisting or squatting motions. Unless the
torn meniscus has locked the knee, many people with a torn meniscus can
walk, stand, sit, and sleep without pain. Other people find that the
torn meniscus prevents them from participating comfortably in their
usual daily activities.Curability Symptoms of a torn meniscus, particularly pain, swelling, catching and locking, can be relieved by surgically removing
or repairing the torn piece of meniscus. Meniscal repair is reserved
for tears in the part of the meniscus that has blood supply.
A slightly different situation exists in the case of a degenerative
meniscal tear associated with osteoarthritis. Osteoarthritis in the
knee is frequently associated with small degenerative meniscal tears
and vice versa. Imaging studies of patients over age 45 with no
symptoms in their knees have found that some people have degenerative
meniscal tears that they aren't aware of.
The acute symptoms from a new degenerative meniscal tear (pain and
swelling) may resolve over a few months time even though the torn area
has not healed or been removed. On the other hand, when mechanical
symptoms such as catching or locking are present, these symptoms are
less likely to resolve without surgery. Mobility A torn meniscus can prevent normal pain-free motion of the knee and
therefore can interfere with the patient's ability to climb stairs or
get in and out of chairs and cars. Sometimes the pain in the knee
causes the brain to shut off the Quadriceps muscle at the knee and
leads to a "giving way" sensation.Daily activities In addition to causing problems in activities of daily living, a torn
meniscus usually interferes with the ability to participate in active
sports, particularly when they involve twisting motions.Incidence Meniscus tears can occur in all age groups. Traumatic tears are most
common in active people from age 10-45. Degenerative tears are most
common in people from age 40 upward.
Acquisition Degenerative meniscal tears are thought to occur as part of the aging
process when the collagen fibers within the meniscus start to break
down and lend less support to the structure of the menicus.
Degenerative tears are usually horizontal in the meniscus producing
both an upper and lower segment of meniscus. These segments usually
don't move out of place and therefore are less likely to produce
mechanical symptoms of catching or locking. Traumatic meniscal tears
are usually radial or vertical in the meniscus and are more likely to
produce a moveable fragment that can catch in the knee and therefore
require surgical treatment.Lifestyle risk factors Degenerative meniscal tears are also more common in smokers.Injury & trauma risk factors Most traumatic meniscal tears occur as a result of a twisting injury
when the knee rotates but the foot stays fixed in position. The
meniscus can also tear from extreme bending of the knee. The
combination of bend, rotation, and sudden kick that occurs in some
forms of martial arts is associated with lateral meniscal tears.Initial symptoms Initial symptoms of a torn meniscus include well-localized pain and
swelling in the knee. The pain is usually either on the inner or outer
side of the knee, not around the kneecap. When the patient recalls a
specific injury that led to the pain and swelling, the swelling often
does not occur until the day after the injury. The swelling is not
necessarily in the same area as the pain.Symptoms A torn meniscus can also produce catching or locking of the knee.
Sometimes the knee is stuck in midrange for days at a time. Sometimes
the patient can "unlock" the knee by bending and twisting it before
trying to straighten it.Progression Over 4-6 weeks, the pain and swelling may decrease and activites of
daily living may become tolerable. However, athletic activities may
reproduce pain and swelling. Sometimes even activities of daily living
such as going up and down stairs or getting in and out of cars may
produce pain in a knee with a torn meniscus.Secondary effects A torn meniscus often causes the knee to make extra joint fluid. There
is more room in the knee for fluid when the knee is slightly bent.
Therefore, people with chronic swelling tend to hold the involved knee
in a bent position and develop hamstring tightness and joint
contracture.
Also, a piece of torn meniscus that is moving in and out of place can
damage the nearby articular (gliding) surfaces and lead to arthritis.Conditions with similar symptoms Sometimes the symptoms of a torn meniscus can be confused with a fragment of arthritic articular cartilage that is hanging from the surface of the bone or that has broken free in the joint.Causes Meniscus tears can occur in all age groups. Traumatic tears are most
common in active people from age 10-45. Degenerative tears are most
common in people from age 40 upward.
Degenerative meniscal tears are thought to occur as part of the
aging process when the collagen fibers within the meniscus start to
break down and lend less support to the structure of the menicus.
Degenerative tears are usually horizontal in the meniscus producing
both an upper and lower segment of meniscus. These segments usually
don't move out of place and therefore are less likely to produce
mechanical symptoms of catching or locking. Traumatic meniscal tears
are usually radial or vertical in the meniscus and are more likely to
produce a moveable fragment that can catch in the knee and therefore
require surgical treatment.
Degenerative meniscal tears are also more common in smokers.
Most traumatic meniscal tears occur as a result of a twisting injury
when the knee rotates but the foot stays fixed in position. The
meniscus can also tear from extreme bending of the knee. The
combination of bend, rotation, and sudden kick that occurs in some
forms of martial arts is associated with lateral meniscal tears. Effects A torn meniscus can prevent normal pain-free motion of the knee and
therefore can interfere with the patient's ability to climb stairs or
get in and out of chairs and cars. Sometimes the pain in the knee
causes the brain to shut off the Quadriceps muscle at the knee and
leads to a "giving way" sensation.
In addition to causing problems in activities of daily living, a
torn meniscus usually interferes with the ability to participate in
active sports, particularly when they involve twisting motions. Diagnosis A torn meniscus can often be diagnosed by a physical exam of the knee.
The doctor will look for swelling, tenderness on the joint line, loss
of motion, and pain with special twisting maneuvers.Diagnostic tests An MRI can be used to confirm the diagnosis of a torn meniscus.Health care team Orthopaedic Surgeons and Sports-Medicine trained primary care doctors are specially trained in the diagnosis of torn meniscus.Finding a doctor Doctors specializing in torn meniscus can be located through university
medical schools, county medical societies, or state orthopaedic
societies. Other resources include the American Academy of Orthopaedic Surgeons and the American Orthopaedic Society for Sports Medicine.Treatment When a torn meniscus is diagnosed but the knee is not locked and the
patient cannot identify a specific incident associated with the onset
of pain, the pain can be treated initially with over the counter pain
medications such as acetaminophen or ibuprofen. The patient should
avoid pivoting and squatting and should work on keeping Quadriceps
muscles strong. If the swelling and pain have not resolved in 6 weeks ,
they usually won't without surgical intervention.
A traumatically torn meniscus usually requires arthroscopic surgical treatment.
This minimally invasive surgical treatment involves either removing or repairing the torn segment of meniscus using an arthroscope.
Because only the outer 1/4-1/5 of the meniscus has blood supply,
repairs are successful when the tear occurs in this vascular region of
the meniscus. Tears in the non-vascular region are unlikely to heal and
therefore are removed.
In the case of a degenerative meniscal tear associated with osteoarthritis,
the expected outcome after surgery is different. Although
arthroscopically treating the torn meniscus and simultaneously trimming
away any shaggy articular cartilage caused by the arthritis may
eliminate mechanical symptoms such as catching or locking, the
non-mechanical symptoms of osteoarthritis ( stiffness, achiness,
weather-related pain) may persist. Therefore, in the setting of a
degenerative meniscal tear with osteoarthritis, the patient and doctor
also need to discuss treatment alternatives for the arthritis such as
injections into the knee or partial or total knee replacement. Self-management Avoiding twisting activites may decrease the symptoms from a torn
meniscus. Additionally, one should do Quadriceps setting exercises with
the knee straight or mini-squats,bending only to 15 degrees, to prevent
giving way and keep the Quadriceps muscle from atrophying.Health care team As mentioned above, some primary care doctors, arthritis doctors, or
rehabilitation medicine doctors can often make the diagnosis. A
fellowship trained orthopaedic surgeon who regularly does arthroscopic
knee surgery is best equipped to treat this problem.Exercise and therapy Most meniscal tears cannot heal because of their limited blood supply.
Nevertheless, Quadriceps muscle strengthening exercises can help
prevent some of the secondary effects of a torn meniscus such as knee
cap pain or the sense of buckling.Medications Medications such as acetaminophen, aspirin, or ibuprofen may relieve
some of the pain, but will not actually treat the underlying meniscal
tear. Anti-inflammatory drugs such as ibuprofen or naproxyn may also
decrease the associated swelling.Surgery Surgery
is the definitive treatment for torn meniscus. The surgery is done
arthroscopically and will include either removal or repair of the torn
part of meniscus.
Repair can be done only when the tear lies in or just adjacent to the
vascular zone of the meniscus.Joint aspiration Removal of excess joint fluid can temporarily bring some relief from
pain, but the meniscus will not heal and the fluid will usually
reaccumulate.Splints or braces Braces may provide an increased sense of security but do not treat the meniscus per se.Strategies for coping Until the tear can be treated arthroscopically,
patients with a torn meniscus can use non-narcotic pain relievers, and
should try to do quadriceps muscle contractions to prevent atrophy that
is associated with knee pain and swelling.One may also need to modify
activities to avoid those that twist the knee.
Adaptive aids Wearing an ace bandage, a knee sleeve, or brace may make the knee feel more secure.Resources More information about torn meniscus may be found at the web site of the American Society for Sports Medicine.Surgical research Current research on the treatment of torn meniscus centers around the
best method for repair of a torn meniscus and placement of a substitute
meniscus when a total meniscal removal has been done previously.Summary of torn meniscus-torn knee cartilage Meniscal tears occur from trauma or degeneration or a combination of the two.
Meniscal tears can produce knee pain, swelling, catching, and locking.
Most meniscal tears do not heal because they are in an anatomic area that has no blood supply.
The definitive treatment for meniscal tears is arthroscopic surgery.
Surgery for Torn Meniscus-torn knee cartilage at the University of Washington If you are interested in making an appointment to discuss this procedure, you can request an appointment using our online referrals website. To request a referral online, please click here. You can also call 206-543-1552 or 425-646-7777 to make an appointment.
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