“Ooohhh… my aching knee!!!”
Insider Secrets on How You Can Get Relief Quickly and Easily!
By Nathan Wei
When your knee hurts, getting relief is all that’s on your mind.
Getting the right relief, though, depends on knowing what’s wrong. The correct
diagnosis will lead to the correct treatment.
Know Your Knee!
The knee is the largest joint in the body. It’s also one of
the most complicated. The knee joint is made up of four bones that are connected
by muscles, ligaments, and tendons. The femur (large thigh bone) interacts with
the two shin bones, the tibia (the larger one) located towards the inside and
the fibula (the smaller one) located towards the outside. Where the femur meets
the tibia is termed the joint line. The patella, (the knee cap) is the bone
that sits in the front of the knee. It slides up and down in a groove in the
lower part of the femur (the femoral groove) as the knee bends and straightens.
Ligaments are the strong rope-like structures that help connect
bones and provide stability. In the knee, there are four major ligaments. On
the inner (medial) aspect of the knee is the medial collateral ligament (MCL)
and on the outer (lateral) aspect of the knee is the lateral collateral ligament
(LCL). The other two main ligaments are found in the center of the knee. These
ligaments are called the anterior cruciate ligament (ACL) and the posterior
cruciate ligament (PCL). They are called cruciate ligaments because the ACL
crosses in front of the PCL. Other smaller ligaments help hold the patella in
place in the center of the femoral groove.
Two structures called menisci sit between the femur and the
tibia. These structures act as cushions or shock absorbers. They also help provide
stability for the knee. The menisci are made of a tough material called fibrocartilage.
There is a medial meniscus and a lateral meniscus. When either meniscus is damaged
it is called a "torn cartilage".
There is another type of cartilage in the knee called hyaline
cartilage. This cartilage is a smooth shiny material that covers the bones in
the knee joint. In the knee, hyaline cartilage covers the ends of the femur,
the femoral groove, the top of the tibia and the underside of the patella. Hyaline
cartilage allows the knee bones to move easily as the knee bends and straightens.
Tendons connect muscles to bone. The large quadriceps muscles
on the front of the thigh attach to the top of the patella via the quadriceps
tendon. This tendon inserts on the patella and then continues down to form the
rope-like patellar tendon. The patellar tendon in turn, attaches to the front
of the tibia. The hamstring muscles on the back of the thigh attach to the tibia
at the back of the knee. The quadriceps muscles are the muscles that straighten
the knee. The hamstring muscles are the main muscles that bend the knee.
Bursae are small fluid filled sacs that decrease the friction
between two tissues. Bursae also protect bony structures. There are many different
bursae around the knee but the ones that are most important are the prepatellar
bursa in front of the knee cap, the infrapatellar bursa just below the kneecap,
the anserine bursa, just below the joint line and to the inner side of the tibia,
and the semimembranous bursa in the back of the knee. Normally, a bursa has
very little fluid in it but if it becomes irritated it can fill with fluid and
become very large.
Is it bursitis... or tendonitis...or arthritis?
Tendonitis generally affects either the quadriceps tendon or
patellar tendon. Repetitive jumping or trauma may set off tendonitis. The pain
is felt in the front of the knee and there is tenderness as well as swelling
involving the tendon. With patellar tendonitis, the infrapatellar bursa will
often be inflamed also. Treatment involves rest, ice, and anti-inflammatory
medication. Injections are rarely used. Physical therapy with ultrasound and
iontopheresis may help.
Bursitis pain is common. The prepatellar bursa may become inflamed
particularly in patients who spend a lot of time on their knees (carpet layers).
The bursa will become swollen. The major concern here is to make sure the bursa
is not infected. The bursa should be aspirated (fluid withdrawn by needle) by
a specialist. The fluid should be cultured. If there is no infection, the bursitis
may be treated with anti-jnflammatory medicines, ice, and physical therapy.
Knee pads should be worn to prevent a recurrence once the initial bursitis is
cleared up.
Anserine bursitis often occurs in overweight people who also
have osteoarthritis of the knee. Pain and some swelling is noted in the anserine
bursa. Treatment consists of steroid injection, ice, physical therapy, and weight
loss.
The semimembranous bursa can be affected when a patient has
fluid in the knee (a knee effusion). The fluid will push backwards and the bursa
will become filled with fluid and cause a sensation of fullness and tightness
in the back of the knee. This is called a Baker’s cyst. If the bursa ruptures,
the fluid will dissect down into the calf.
The danger here is that it may look like a blood clot in the
calf. A venogram and ultrasound test will help differentiate a ruptured Baker’s
cyst from a blood clot. The Baker’s cyst is treated with aspiration of the fluid
from the knee along with steroid injection, ice, and elevation of the leg.
Knock out knee arthritis... simple steps you can take! Younger
people who have pain in the front of the knee have what is called patellofemoral
syndrome (PFS). Two major conditions cause PFS. The first is chondromalacia
patella. This is a condition where the cartilage on the underside of the knee
cap softens and is particularly common in young women.
Another cause of pain behind the knee cap in younger people
may be a patella that doesn’t track normally in the femoral groove. For both
chondromalacia as well as a poorly tracking patella, special exercises, taping,
and anti-inflammatory medicines may be helpful. If the patellar tracking becomes
a significant problem despite conservative measures, surgery is need.
While many types of arthritis may affect the knee, osteoarthritis
is the most common. Osteoarthritis usually affects the joint between the femur
and tibia in the medial (inner) compartment of the knee. Osteoarthritis may
also involve the joint between the femur and tibia on the outer side of the
knee as well as the joint between the femur and patella. Why osteoarthritis
develops is still being scrutinized carefully. It seems to consist of a complex
interaction of genetics, mechanical factors, and immune system involvement.
The immune system attacks the joint through a combination of degradative enzymes
and inflammatory chemical messengers called cytokines.
Patients will sometimes feel a sensation of rubbing or grinding.
The knee will become stiff if the patient sits for any length of time. With
local inflammation, the patient may experience pain at night and get relief
from sleeping with a pillow between the knees. Occasionally, locking and clicking
may be noticed. Patients with osteoarthritis may also tear the fibrocartilage
cushions (menisci) in the knee more easily than people without osteoarthritis.
So how is the arthritis treated?
An obvious place to start is weight reduction for patients who
carry around too many pounds.
Strengthening exercises for the knee are also useful for many
people. These should be done under the supervision of a physician or physical
therapist.
Other therapies include ice, anti inflammatory medicines, and
occasionally steroid injections. Glucosamine and chondroitin supplements may
be helpful. A word of caution... make sure the preparation you buy is pure and
contains what the label says it does. The supplement industry is unregulated...
so buyer beware!
Injections of the knee with viscosupplements – lubricants- are
particularly useful for many patients. Special braces may help to unload the
part of the joint that is affected.
Arthroscopic techniques may be beneficial in special circumstances.
Occasionally, a surgical procedure called an osteotomy, where a wedge of bone
is removed from the tibia to “even things out,” may be recommended. Joint replacement
surgery is required for end stage knee arthritis.
Research is being done to develop medicines that will slow down
the rate of cartilage loss. Targets for these new therapies include the destructive
enzymes and/or cytokines that degrade cartilage. It is hoped that by inhibiting
these enzymes and cytokines and by boosting the ability of cartilage to repair
itself, that therapies designed to actually reverse osteoarthritis may be created.
These are referred to as disease-modifying osteoarthritis drugs or “DMOADs.”
Genetic markers may identify high risk patients who need more aggressive therapies.
Newer compounds that are injected into the knee and provide
healing as well as lubrication are also being developed. And finally, less invasive
surgical techniques are also being looked at. Recent technological advances
in “mini” knee replacement look very promising.
Dr. Wei (pronounced “way”) is a board-certified rheumatologist
and Clinical Director of the nationally respected Arthritis and Osteoporosis
Center of Maryland. He is a Clinical Assistant Professor of Medicine at the
University of Maryland School of Medicine and has served as a consultant to
the Arthritis Branch of the National Institutes of Health. He is a Fellow of
the American College of Rheumatology and the American College of Physicians.
Dr. Wei is the editor of the arthritis-treatment-and-relief.com
website.
