A complete knee examination is always done
for a knee complaint. Both of your knees will be checked, and the results for
the injured knee will be compared to those of the healthy knee. Your doctor
will also check that the nerves and blood vessels are intact.
Knee pain is incredibly common. In the United States, it's responsible for about 1/3 of all doctor's visits for muscle and bone pain. Knee pain is a special problem for athletes -- over half of all athletes endure it every year.
Some of the most common reasons for knee pain are swollen or torn ligaments, meniscus (cartilage) tears, and runner's knee. But the knee is a complex joint, and there's plenty more that can go wrong.
Other conditions that cause knee pain include:
Inspect your knee visually for redness,
swelling, deformity, or skin changes.
Feel your knee (palpation)
for warmth or coolness, swelling, tenderness, blood flow, and
Test your knee's range of motion and listen for sounds.
In a passive test, your doctor will move your leg and knee joint. In an active
test, you will use your muscles to move your leg and knee joint. At the same
time, your doctor will listen for popping, grinding, or clicking
The Valgus and Varus tests, which
check the medial and
lateral collateral ligaments. In these tests, while
you lie on the examining table, your doctor places one hand on your knee joint
and the other on your ankle and moves your leg side-to-side.
posterior drawer test, which checks the
posterior cruciate ligament. In this test, you lie on the table with your knee
bent at a 90-degree angle and your foot flat on the table. Your doctor will put
his or her hands around your knee and push the top of your knee with the
The Lachman test, which checks the
anterior cruciate ligament (ACL). In this test, while you lie on the table, your
doctor will slightly bend your knee and hold your thigh with one hand. With the
other hand, he or she will hold the upper part of your calf and pull forward.
The Lachman test diagnoses a complete ACL tear.
A pivot shift test, which checks the ACL. In this test, the leg
is extended and your doctor holds your calf with one hand while twisting the
knee and pushing toward the body. It is often done just before a knee
arthroscopy and after
anesthesia has completely relaxed the muscles.
A McMurray test may be done if your
doctor suspects a problem with the
menisci based on your medical history and the above
examinations. In this test, while you lie on the table, your doctor holds your
knee and the bottom of your foot. He or she then pushes your leg up (bending
your knee) while turning the leg and pressing on the knee. If there is pain and
the sound or feeling of a click, the menisci may be damaged.
Arthrometric testing of the knee may also be done. In this
test, your doctor will use an instrument to measure the looseness of your knee.
This test is especially useful in people whose pain or physical size makes a
physical exam difficult. An arthrometer has two sensor pads and a pressure
handle that allows your doctor to put force on the knee. The instrument is
strapped on to your lower leg so that the sensor pads are placed on the knee
cap and the small bump just below it (tibial tubercle). Your doctor then
measures pressure by pulling or pushing on the pressure handle.
Your exam may also include other tests to assess the degree of the injury
and to identify damage to other parts of the knee.
Why It Is Done
A complete physical exam of the knee
is always done for a knee complaint, whether the complaint is from a recent or
sudden (acute) injury or from long-lasting or recurrent (chronic)
In general, in a normal knee exam:
The knee has its natural
The knee is not tender when touched.
knees look and move the same way.
There are no signs of fluid in or
around the knee joint.
The knee and leg move normally when the
ligaments are examined.
There is no abnormal clicking, popping, or
grinding when knee structures are moved or stressed.
The toes are
pink and warm, and there is no numbness in the lower leg or foot.
If any of these findings are not true-for example, the knee
is tender-you may have a knee injury. But the results of a knee exam vary
depending on whether the exam is for a sudden injury to the knee or for
long-term symptoms and also depending on how long it has been since the injury
occurred. An abnormal finding does not always mean that your knee is injured.
Your doctor will use the results of the exam, plus your medical history, to
make a diagnosis.
What To Think About
These tests provide the best
information if there is little or no knee swelling, you are able to relax, and
your doctor is able to move your knee and leg freely. If this is not the case,
it may be difficult to accurately check your knee.