Knee Pain

Knee pain is one of the most common musculoskeletal complaint that brings people to their doctor. With today's increasingly active society, the number of knee problems is increasing. Knee pain has a wide variety of specific causes and treatments.
Anatomy of the Knee pain

The knee joint's main function is to bend and straighten. The knee, more than just a simple hinge, however, also twists and rotates. In order to perform all of these actions and to support the entire body while doing so, the knee relies on a number of structures, including bones, ligaments, tendons, and cartilage.

 Bones

The knee joint involves three bones.

The thighbone or femur comprises the top portion of the joint.

One of the bones in the lower leg (or calf area), the tibia, provides the bottom portion of the joint.

The kneecap or patella rides along the front of the femur.

The remaining bone in the calf, the fibula, is not involved in the knee joint but is close to the outer portion of the joint.

 Ligaments

Ligaments are fibrous bands that connect bones to each other.

The knee includes four important ligaments, all four of which connect the femur to the tibia:

The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) provide front and back (anterior and posterior) and rotational stability to the kneeThe medial collateral ligament (MCL) and lateral collateral ligament (LCL) located along the inner (medial) and outer (lateral) sides of the knee provide medial and lateral stability to the knee.

Tendons

Tendons are fibrous bands similar to ligaments.

 Instead of connecting bones to other bones as ligaments do, tendons connect muscles to bones.

The two important tendons in the knee are (1) the quadriceps tendon connecting the quadriceps muscle, which lies on the front of the thigh, to the patella and (2) the patellar tendon connecting the patella to the tibia (technically this is a ligament because it connects two bone

The quadriceps and patellar tendons as well as the patella itself are sometimes called the extensor mechanism, and together with the quadriceps muscle they facilitate leg extension (straightening).

Cartilage

Cartilaginous structures called menisci (one is a meniscus) line the top of the tibia and lie between the tibia and the two knuckles at the bottom of the femur (called the femoral condyles).

Menisci provide both space and cushion for the knee joint.

 Bursae

Bursae (one is a bursa) are fluid-filled sacs that help to cushion the knee. The knee contains three important groups of bursae.

The prepatellar bursae lie in front of the patella.

The anserine bursae are located on the inner side of the knee about 2 inches below the joint.

The infrapatellar bursae are located underneath the patella.
Diagnosis of knee pain

History: Even in today's world of technology, physicians rely on a detailed history and examination more than any single test.

The doctor will typically want to know the exact nature of the pain.

Where in the knee is your pain?

What does the pain feel like?

Has it happened before?

What makes it better or worse?

How long have you had pain in the knee?

The doctor will also want to know a bit about you

Do you have any major medical problems?

How active is your lifestyle?

What are the names of the medications you are taking?

The doctor will want to know about any related symptoms.

Do you still have normal sensation in your foot and lower leg?

Have you been having fevers?

Physical examination

The doctor will likely have you disrobe to completely expose the knee.

The doctor will then inspect the knee and press around the knee to see exactly where it is tender.

 In addition, the doctor may perform a number of maneuvers to stress the ligaments, tendons, and menisci of the knee and evaluate the integrity of each of these.

These maneuvers can establish potential tendon, ligament, or meniscus injuries.

X-rays and CT scans

Depending on your particular history and examination, the doctor may suggest X-rays of the knee. X-rays show fractures (broken bones) and dislocations of bones in the knee as well as arthritic changes and abnormally large or small joint spaces.

Rarely, the doctor may order a CT scan (a three-dimensional X-ray) of the knee to precisely define a fracture or deformity.

Both X-rays and CT scans are excellent for diagnosing fractures. They both are also poor, however, at evaluating soft-tissue structures of the knee such as ligaments, tendons, and the menisci.

MRI

Magnetic resonance imaging (MRI) uses large magnets to create a three-dimensional image of the knee.

In contrast to CT scans, MRIs do not image bones and fractures well.

Also in contrast to CT scans, MRIs are excellent for evaluating ligaments and tendons for injuries.

Fluid removal

he knee and all bursae of the knee are filled with fluid.

if your symptoms suggest infection, inflammation, or certain types of arthritis, your physician may use a needle to remove fluid from the knee.

The removal of the fluid will sometimes decrease the pain you have been experiencing

This fluid will then be analyzed to better clarify the diagnosis.

Crystals, which suggest crystalline arthritis, often can be seen under the microscope, by evaluating the fluid further infection can be detected.

 Blood tests: The doctor may also elect to perform certain blood tests to evaluate for signs of infection or diseases such as rheumatoid arthritis and diabetes.

Arthroscopy

The orthopedic surgeon may elect to perform arthroscopy if you have chronic knee pain.

This is a surgical procedure where the doctor will place a fiberoptic camera within the knee joint itself.

By doing so, the surgeon may be able to see small particles in the knee or to look more closely at damaged menisci or cartilage.

The doctor may also be able to repair damage by shaving down torn cartilage or removing particles from the knee while the camera shows the inside of your knee.