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