Knee

One of the most common knee injuries is an anterior cruciate ligament sprain or tear.Athletes who participate in high demand sports like soccer, football, and basketball are more likely to injure their anterior cruciate ligaments.If you have injured your anterior cruciate ligament, you may require surgery to regain full function of your knee. This will depend on several factors, such as the severity of your injury and your activity level.

Anatomy

Three bones meet to form your knee joint: your thighbone (femur), shinbone (tibia), and kneecap (patella). Your kneecap sits in front of the joint to provide some protection.

Bones are connected to other bones by ligaments. There are four primary ligaments in your knee. They act like strong ropes to hold the bones together and keep your knee stable.

Collateral Ligaments

These are found on the sides of your knee. The medial collateral ligament is on the inside and the lateral collateral ligament is on the outside. They control the sideways motion of your knee and brace it against unusual movement.

Cruciate Ligaments

These are found inside your knee joint. They cross each other to form an "X" with the anterior cruciate ligament in front and the posterior cruciate ligament in back. The cruciate ligaments control the back and forth motion of your knee.

The anterior cruciate ligament runs diagonally in the middle of the knee. It prevents the tibia from sliding out in front of the femur, as well as provides rotational stability to the knee.

normal knee anatomy

Description

About half of all injuries to the anterior cruciate ligament occur along with damage to other structures in the knee, such as articular cartilage, meniscus, or other ligaments.

complete tear of the ACL

Injured ligaments are considered "sprains" and are graded on a severity scale.

Grade 1 Sprains. The ligament is mildly damaged in a Grade 1 Sprain. It has been slightly stretched, but is still able to help keep the knee joint stable.

Grade 2 Sprains. A Grade 2 Sprain stretches the ligament to the point where it becomes loose. This is often referred to as a partial tear of the ligament.

Grade 3 Sprains. This type of sprain is most commonly referred to as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.

Partial tears of the anterior cruciate ligament are rare; most ACL injuries are complete or near complete tears.

Cause

The anterior cruciate ligament can be injured in several ways:

  • Changing direction rapidly
  • Stopping suddenly
  • Slowing down while running
  • Landing from a jump incorrectly
  • Direct contact or collision, such as a football tackle

Several studies have shown that female athletes have a higher incidence of ACL injury than male athletes in certain sports. It has been proposed that this is due to differences in physical conditioning, muscular strength, and neuromuscular control. Other suggested causes include differences in pelvis and lower extremity (leg) alignment, increased looseness in ligaments, and the effects of estrogen on ligament properties.

Symptoms

When you injure your anterior cruciate ligament, you might hear a "popping" noise and you may feel your knee give out from under you. Other typical symptoms include:

  • Pain with swelling. Within 24 hours, your knee will swell. If ignored, the swelling and pain may resolve on its own. However, if you attempt to return to sports, your knee will probably be unstable and you risk causing further damage to the cushioning cartilage (meniscus) of your knee.
  • Loss of full range of motion
  • Tenderness along the joint line
  • Discomfort while walking

    Doctor Examination

    Physical Examination and Patient History

    During your first visit, your doctor will talk to you about your symptoms and medical history.

    During the physical examination, your doctor will check all the structures of your injured knee, and compare them to your non-injured knee. Most ligament injuries can be diagnosed with a thorough physical examination of the knee.

    Imaging Tests

    Other tests which may help your doctor confirm your diagnosis include:

    X-rays. Although they will not show any injury to your anterior cruciate ligament, x-rays can show whether the injury is associated with a broken bone.

    Magnetic resonance imaging (MRI) scan. This study creates better images of soft tissues like the anterior cruciate ligament. However, an MRI is usually not required to make the diagnosis of a torn ACL.

The posterior cruciate ligament is located in the back of the knee. It is one of several ligaments that connect the femur (thighbone) to the tibia (shinbone). The posterior cruciate ligament keeps the tibia from moving backwards too far.An injury to the posterior cruciate ligament requires a powerful force. A common cause of injury is a bent knee hitting a dashboard in a car accident or a football player falling on a knee that is bent.

Anatomy

Two bones meet to form your knee joint: your thighbone (femur) and shinbone (tibia). Your kneecap sits in front of the joint to provide some protection.

Bones are connected to other bones by ligaments. There are four primary ligaments in your knee. They act like strong ropes to hold the bones together and keep your knee stable.

Collateral ligaments. These are found on the sides of your knee. The medial collateral ligament is on the inside and the lateral collateral ligament is on the outside. They control the sideways motion of your knee and brace it against unusual movement.

Cruciate ligaments. These are found inside your knee joint. They cross each other to form an "X" with the anterior cruciate ligament in front and the posterior cruciate ligament in back. The cruciate ligaments control the back and forth motion of your knee.

Normal knee anatomy including the ligaments

Normal knee anatomy. The posterior cruciate ligament, located in the back of the knee, is one of several ligaments that connect the femur (thighbone) to the tibia (shinbone).

The posterior cruciate ligament keeps the shinbone from moving backwards too far. It is stronger than the anterior cruciate ligament and is injured less often. The posterior cruciate ligament has two parts that blend into one structure that is about the size of a person's little finger.

Description

Injuries to the posterior cruciate ligament are not as common as other knee ligament injuries. In fact, they are often subtle and more difficult to evaluate than other ligament injuries in the knee.

Many times a posterior cruciate ligament injury occurs along with injuries to other structures in the knee such as cartilage, other ligaments, and bone.

Injured ligaments are considered "sprains" and are graded on a severity scale.

Grade 1 Sprains. The ligament is mildly damaged in a Grade 1 Sprain. It has been slightly stretched, but is still able to help keep the knee joint stable.

Grade 2 Sprains. A Grade 2 Sprain stretches the ligament to the point where it becomes loose. This is often referred to as a partial tear of the ligament.

Grade 3 Sprains. This type of sprain is most commonly referred to as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.

Complete tear of the posterior cruciate ligament

A complete tear of the posterior cruciate ligament, back view.

Posterior cruciate ligament tears tend to be partial tears with the potential to heal on their own. People who have injured just their posterior cruciate ligaments are usually able to return to sports without knee stability problems.

Cause

An injury to the posterior cruciate ligament can happen many ways. It typically requires a powerful force.

  • A direct blow to the front of the knee (such as a bent knee hitting a dashboard in a car crash, or a fall onto a bent knee in sports)
  • Pulling or stretching the ligament (such as in a twisting or hyperextension injury)
  • Simple misstep

Symptoms

The typical symptoms of a posterior cruciate ligament injury are:

  • Pain with swelling that occurs steadily and quickly after the injury
  • Swelling that makes the knee stiff and may cause a limp
  • Difficulty walking
  • The knee feels unstable, like it may "give out"

Doctor Examination

During your first visit, your doctor will talk to you about your symptoms and medical history.

During the physical examination, your doctor will check all the structures of your injured knee, and compare them to your non-injured knee. Your injured knee may appear to sag backwards when bent. It might slide backwards too far, particularly when it is bent beyond a 90° angle. Other tests which may help your doctor confirm your diagnosis include X-rays and magnetic resonance imaging (MRI). It is possible, however, for these pictures to appear normal, especially if the injury occurred more than 3 months before the tests.

X-rays. Although they will not show any injury to your posterior cruciate ligament, X-rays can show whether the ligament tore off a piece of bone when it was injured. This is called an avulsion fracture.

MRI. This study creates better images of soft tissues like the posterior cruciate ligament.

Meniscus tears are among the most common knee injuries. Athletes, particularly those who play contact sports, are at risk for meniscus tears. However, anyone at any age can tear the meniscus. When people talk about "torn cartilage" in the knee, they are usually referring to a torn meniscus.

Anatomy

Three bones meet to form your knee joint: your thighbone (femur), shinbone (tibia), and kneecap (patella).

Two wedge-shaped pieces of fibrocartilage act as "shock absorbers" between your thighbone and shinbone. These are the menisci. The menisci help to transmit weight from one bone to another and play an important role in knee stability.

Normal knee anatomy

Normal knee anatomy. The menisci are two rubbery disks that help cushion the knee joint.

Description

The meniscus can tear from acute trauma or as the result of degenerative changes that happen over time.  Tears are noted by how they look, as well as where the tear occurs in the meniscus. Common tears include bucket handle, flap, and radial.

Sports-related meniscus injuries often occur along with other knee injuries, such as anterior cruciate ligament (ACL) tears.

Common meniscus tears

Types of meniscus tears:
(Left)
 Bucket handle tear. (Right) Flap tear.

 

Common meniscus tears

(Left) Radial tear. (Right) Degenerative tear.

Cause

Acute meniscus tears often happen during sports. These can occur through either a contact or non-contact injury—for example, a pivoting or cutting injury.

As people age, they are more likely to have degenerative meniscus tears. Aged, worn tissue is more prone to tears. An awkward twist when getting up from a chair may be enough to cause a tear in an aging meniscus.

Symptoms

You might feel a "pop" when you tear the meniscus. Most people can still walk on their injured knee and many athletes are able to keep playing with a tear. Over 2 to 3 days, however, the knee will gradually become more stiff and swollen.

The most common symptoms of a meniscus tear are:

  • Pain
  • Stiffness and swelling
  • Catching or locking of your knee
  • The sensation of your knee "giving way"
  • Inability to move your knee through its full range of motion

Doctor Examination

Physical Examination

After discussing your symptoms and medical history, your doctor will examine your knee. He or she will check for tenderness along the joint line where the meniscus sits. This often signals a tear.

knee exam

During the exam, your doctor will look for signs of tenderness along the joint line.

One of the main tests for meniscus tears is the McMurray test. Your doctor will bend your knee, then straighten and rotate it. This puts tension on a torn meniscus. If you have a meniscus tear, this movement may cause pain, clicking, or a clunking sensation within the joint.

McMurray test

The McMurray test (shown here) will help your doctor determine if you have a meniscus tear.

Imaging Tests

Because other knee injuries can cause similar symptoms, your doctor may order imaging tests to help confirm the diagnosis.

X-rays. X-rays provide images of dense structures, such as bone. Although an x-ray will not show a meniscus tear, your doctor may order one to look for other causes of knee pain, such as osteoarthritis.

Magnetic resonance imaging (MRI) scans.  These studies assess the soft tissues in your knee joint, including the menisci, cartilage, tendons, and ligaments.

normal meniscus and meniscus tear

MRI scans show (left) a normal meniscus and (right) a torn meniscus. The tear can be seen as a white line through the dark body of the meniscus.

The meniscus is a wedge-shaped piece of cartilage that sits in between the bones of the knee and acts as a cushion to protect the bones during movement. Each knee has two menisci.Healthy menisci are shaped like crescent moons (in fact, "meniscus" comes from the Greek word for crescent). A discoid meniscus is thicker than normal, and often oval or disc-shaped. It is more prone to injury than a normally shaped meniscus.

People with discoid meniscus may go through their entire lives and never experience any problems. If a discoid meniscus does not cause pain or discomfort, no treatment is needed. Some people, however, will have knee problems related to the discoid meniscus. Symptoms often begin during childhood.

Anatomy

The menicus acts as a "shock absorber" between your femur (thighbone) and tibia (shinbone). It protects the thin articular cartilage that covers the ends of the bones and helps the knee to easily bend and straighten.

There are two menisci in the knee: the medial meniscus on the inside of the knee, and the lateral meniscus on the outside.

Normal anatomy of the knee

Normal knee anatomy. Discoid meniscus most often affects the lateral meniscus, which is the on the outside of the knee joint.

The menisci are attached to the femur bone by a strong tissue called the meniscofemoral ligament. This ligament also provides a blood supply to a small portion of the meniscus.

Description

In many cases, a discoid meniscus is shaped like a half moon or complete circle, rather than a crescent moon. It most often occurs on the lateral side (outside) of the knee, and can sometimes be found in both knees.

Types of Discoid Meniscus

There are three types of discoid menisci:

  • Incomplete. The meniscus is slightly thicker and wider than normal.
  • Complete. The meniscus completely covers the tibia.
  • Hypermobile Wrisberg. This occurs when the ligaments that attach the meniscus to the femur and tibia are absent. Without these ligaments, even a fairly normally shaped meniscus can sometimes slip into the joint and cause pain, as well as locking and popping of the knee.

 incomplete and complete discoid menisci

Here are cross-section views of incomplete and complete discoid menisci

Discoid Meniscus Injuries

A discoid meniscus is more prone to injury than a normal meniscus. The thick, abnormal shape of a discoid meniscus makes it more likely to get stuck in the knee or tear. If the meniscofemoral ligament attachment to the femur is also missing, the risk for injury is even greater.

Once injured, even a normal meniscus is difficult to heal. This is because the meniscus lacks a strong blood supply and the nutrients that are essential to healing cannot reach the injured tissues.

In many cases of discoid meniscus, patients experience symptoms without there being any injury to the meniscus.

Cause

The cause of discoid meniscus is not known. It is a congenital (present at birth) defect.

Injuries to the discoid meniscus often occur with twisting motions to the knee, such as during sports that require pivoting or fast changes in direction.

Symptoms

The most common symptoms of a discoid meniscus or torn discoid meniscus are:

  • Pain
  • Stiffness or swelling
  • Catching, popping, locking of the knee
  • Feeling that the knee is "giving way"
  • Inability to fully extend (straighten) the knee

Doctor Examination

Medical History and Physical Examination

After discussing your child's medical history and any events that occurred before symptoms started, your doctor will examine your child's knee.

Your child may or may not have tenderness where the bones meet.

To test for discoid meniscus, your doctor will twist your child's knee with the knee bent and straightened. In many cases of discoid meniscus, there is a popping or clunking sensation. This can sometimes even be heard. In extreme cases, part of the meniscus will pop out of the knee joint and can be seen right under the skin.

Imaging Tests

X-rays. Although x-rays do not show tears of soft tissues like the meniscus, they can show whether there are other problems in the knee. In addition, because the discoid meniscus is so thick, the space between the femur and tibia on the lateral part of the knee may appear widened on an x-ray.Magnetic resonance imaging (MRI) scan. This study can create detailed images of the soft tissues of the knee joint and is the best imaging test for discoid meniscus.

The MRI can show the abnormal shape of the discoid meniscus, as well as tears within the meniscus. However, the rare Wrisberg type of discoid meniscus cannot be tested with an MRI scan because the problem only occurs when the patient is moving.

MRI of discoid meniscus

This MRI scan shows a discoid lateral meniscus (arrow). Note how much thicker the affected meniscus is when compared with the meniscus on the inside of the knee.

Reproduced from Johnson TR, Steinbach LS (eds.): Essentials of Musculoskeletal Imaging. Rosemont, IL. American Academy of Orthopaedic Surgeons, 2005, p. 554.

An MRI study involves lying still for 30-45 minutes. Many young patients require some sedation or anesthesia to complete the test.

The knee is the largest joint in your body and one of the most complex. It is also vital to movement.

Your knee ligaments connect your thighbone to your lower leg bones. Knee ligament sprains or tears are a common sports injury.

In the past, injuring more than one knee ligament would put an end to future sports activities. Today, many athletes are able to return to high level sports following multiple ligament injuries.

Normal knee anatomy

Normal knee anatomy.  The knee is made up of four main things: bones, cartilage, ligaments, and tendons.

Anatomy

Three bones meet to form your knee joint: your thighbone (femur), shinbone (tibia), and kneecap (patella). Your kneecap sits in front of the joint to provide some protection.

Bones are connected to other bones by ligaments. There are four primary ligaments in your knee. They act like strong ropes to hold the bones together and keep your knee stable.

Collateral Ligaments

These are found on the sides of your knee. The medial collateral ligament is on the inside and the lateral collateral ligament is on the outside. They control the sideways motion of your knee and brace it against unusual movement.

Cruciate Ligaments

These are found inside your knee joint. They cross each other to form an "X" with the anterior cruciate ligament in front and the posterior cruciate ligament in back. The cruciate ligaments control the back and forth motion of your knee.

Description

Because the knee joint relies just on these ligaments and surrounding muscles for stability, it is easily injured. Any direct contact to the knee or hard muscle contraction — such as changing direction rapidly while running — can injure a knee ligament.

Injured ligaments are considered "sprains" and are graded on a severity scale.

Grade 1 Sprains. The ligament is mildly damaged in a Grade 1 Sprain. It has been slightly stretched, but is still able to help keep the knee joint stable.

Grade 2 Sprains. A Grade 2 Sprain stretches the ligament to the point where it becomes loose. This is often referred to as a partial tear of the ligament.

Grade 3 Sprains. This type of sprain is most commonly referred to as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.

It is possible to injure two or more ligaments at the same time. These multiple injuries can have serious complications. They can disrupt blood supply to the leg. They can also affect the nerves that supply the muscles of the limb. In severe cases, multiple ligament injuries may lead to amputation.

The MCL is injured more often than the LCL. Due to the more complex anatomy of the outside of the knee, if you injure your LCL, you usually injure other structures in the joint, as well.

combined knee ligament tears

Tears of the anterior cruciate ligament (left) can occur along with injuries to the medial collateral ligament (right).

Arthritis is inflammation of one or more of your joints. Pain, swelling, and stiffness are the primary symptoms of arthritis. Any joint in the body may be affected by the disease, but it is particularly common in the knee.

Knee arthritis can make it hard to do many everyday activities, such as walking or climbing stairs. It is a major cause of lost work time and a serious disability for many people.

The most common types of arthritis are osteoarthritis and rheumatoid arthritis, but there are more than 100 different forms. While arthritis is mainly an adult disease, some forms affect children.

Although there is no cure for arthritis, there are many treatment options available to help manage pain and keep people staying active.

Anatomy

The knee is the largest and strongest joint in your body. It is made up of the lower end of the femur (thighbone), the upper end of the tibia (shinbone), and the patella (kneecap). The ends of the three bones that form the knee joint are covered with articular cartilage, a smooth, slippery substance that protects and cushions the bones as you bend and straighten your knee.

Two wedge-shaped pieces of cartilage called meniscus act as "shock absorbers" between your thighbone and shinbone. They are tough and rubbery to help cushion the joint and keep it stable.

The knee joint is surrounded by a thin lining called the synovial membrane. This membrane releases a fluid that lubricates the cartilage and reduces friction.

 

normal knee anatomy

Normal knee anatomy.  The knee is made up of bones, cartilage, ligaments, and tendons.

Description

The major types of arthritis that affect the knee are osteoarthritis, rheumatoid arthritis, and posttraumatic arthritis.

Osteoarthritis

Osteoarthritis is the most common form of arthritis in the knee. It is a degenerative,"wear-and-tear" type of arthritis that occurs most often in people 50 years of age and older, although it may occur in younger people, too.

In osteoarthritis, the cartilage in the knee joint gradually wears away. As the cartilage wears away, it becomes frayed and rough, and the protective space between the bones decreases. This can result in bone rubbing on bone, and produce painful bone spurs.

Osteoarthritis usually develops slowly and the pain it causes worsens over time.

osteoarthritis and bone spurs

Osteoarthritis often results in bone rubbing on bone. Bone spurs are a common feature of this form of arthritis.

Rheumatoid Arthritis

Rheumatoid arthritis is a chronic disease that attacks multiple joints throughout the body, including the knee joint. It is symmetrical, meaning that it usually affects the same joint on both sides of the body.

In rheumatoid arthritis, the synovial membrane that covers the knee joint begins to swell, This results in knee pain and stiffness.

Rheumatoid arthritis is an autoimmune disease. This means that the immune system attacks its own tissues. The immune system damages normal tissue (such as cartilage and ligaments) and softens the bone.

Posttraumatic Arthritis

Posttraumatic arthritis is form of arthritis that develops after an injury to the knee. For example, a broken bone may damage the joint surface and lead to arthritis years after the injury. Meniscal tears and ligament injuries can cause instability and additional wear on the knee joint which, over time, can result in arthritis.

Symptoms

A knee joint affected by arthritis may be painful and inflamed. Generally, the pain develops gradually over time, although sudden onset is also possible. There are other symptoms, as well:

  • The joint may become stiff and swollen, making it difficult to bend and straighten the knee.
  • Pain and swelling may be worse in the morning, or after sitting or resting.
  • Vigorous activity may cause pain to flare up.
  • Loose fragments of cartilage and other tissue can interfere with the smooth motion of joints. The knee may "lock" or "stick" during movement. It may creak, click, snap or make a grinding noise (crepitus).
  • Pain may cause a feeling of weakness or buckling in the knee.
  • Many people with arthritis note increased joint pain with changes in the weather.

Doctor Examination

During your appointment, your doctor will talk with you about your symptoms and medical history, conduct a physical examination, and possibly order diagnostic tests, such as x-rays or blood tests.

Physical Examination

During the physical examination, your doctor will look for:

  • Joint swelling, warmth, or redness
  • Tenderness around the knee
  • Range of passive (assisted) and active (self-directed) motion
  • Instability of the joint
  • Crepitus (a grating sensation inside the joint) with movement
  • Pain when weight is placed on the knee
  • Problems with your gait (the way you walk)
  • Any signs of injury to the muscles, tendons, and ligaments surrounding the knee
  • Involvement of other joints (an indication of rheumatoid arthritis)

Imaging Tests

  • X-rays. These imaging tests provide detailed pictures of dense structures, such as bone. They can help distinguish among various forms of arthritis. X-rays of an arthritic knee may show a narrowing of the joint space, changes in the bone, and the formation of bone spurs (osteophytes).
  • Other tests. Occasionally, a magnetic resonance imaging (MRI) scan or a computerized tomography (CT) scan may be needed to determine the condition of the bone and soft tissues of your knee.

x-rays of normal knee and knee with osteoarthritis

(Left) In this x-ray of a normal knee, the space between the bones indicates healthy cartilage (arrows). (Right) This x-ray of an arthritic knee shows severe loss of joint space.

Laboratory Tests

Your doctor may also recommend blood tests to determine which type of arthritis you have. With some types of arthritis, including rheumatoid arthritis, blood tests will help with a proper diagnosis.

Shin splints are a common exercise-related problem. The term "shin splints" refers to pain along the inner edge of the shinbone (tibia).

Shin splints typically develop after physical activity. They are often associated with running. Any vigorous sports activity can bring on shin splints, especially if you are just starting a fitness program.

Simple measures can relieve the pain of shin splints. Rest, ice, and stretching often help. Taking care not to overdo your exercise routine will help prevent shin splints from coming back.

Description

Shin splints (medial tibial stress syndrome) is an inflammation of the muscles, tendons, and bone tissue around your tibia. Pain typically occurs along the inner border of the tibia, where muscles attach to the bone.

Location of pain from shin splints

Shin splint pain most often occurs on the inside edge of your tibia (shinbone).
Reproduced and adapted with permission from Gruel CR: Lower Leg, in Sullivan JA, Anderson SJ (eds): Care of the Young Athlete. Rosemont, IL, American Academy of Orthopaedic Surgeon, 2000.

Cause

In general, shin splints develop when the muscle and bone tissue (periosteum) in the leg become overworked by repetitive activity.

Shin splints often occur after sudden changes in physical activity. These can be changes in frequency, such as increasing the number of days you exercise each week. Changes in duration and intensity, such as running longer distances or on hills, can also cause shin splints.

Other factors that contribute to shin splints include:

  • Having flat feet or abnormally rigid arches
  • Exercising with improper or worn-out footwear

Runners are at highest risk for developing shin splints. Dancers and military recruits are two other groups frequently diagnosed with the condition.

Photo of flat feet

Flat feet can increase stress on lower leg muscles during exercise.

Symptoms

The most common symptom of shin splints is pain along the border of the tibia. Mild swelling in the area may also occur.

Shin splint pain may:

  • Be sharp and razor-like or dull and throbbing
  • Occur both during and after exercise
  • Be aggravated by touching the sore spot

Doctor Examination

After discussing your symptoms and medical history, your doctor will examine your lower leg. An accurate diagnosis is very important. Sometimes, other problems may exist that can have an impact on healing.

Your doctor may order additional imaging tests to rule out other shin problems. Several conditions can cause shin pain, including stress fractures, tendinitis, and chronic exertional compartment syndrome.

Exam for shin splints

Your doctor will examine your lower leg, checking for pain and tenderness along the inner border of the tibia (shinbone).

Stress Fracture

If your shin splints are not responsive to treatment, your doctor may want to make sure you do not have a stress fracture. A stress fracture is a small crack(s) in the tibia caused by stress and overuse.

Imaging tests that create pictures of anatomy help to diagnose conditions. A bone scan and magnetic resonance imaging (MRI) study will often show stress fractures in the tibia.

Tendinitis

Tendons attach muscles to bones. Tendinitis occurs when tendons become inflamed. This can be painful like shin splints, especially if there is a partial tear of the involved tendon. An MRI can help diagnose tendinitis.

Chronic Exertional Compartment Syndrome

An uncommon condition called chronic exertional compartment syndrome causes symptoms like shin splints. Compartment syndrome is a painful condition that occurs when pressure within the muscles builds to dangerous levels. In chronic exertional compartment syndrome, this is brought on by exercise. Pain usually resolves soon after the activity stops.

The tests used to diagnose this condition involve measuring the pressure within the leg compartments before and after exercise.

Patellar Dislocation and Instability in Children (Unstable Kneecap)

Your child's kneecap (patella) is usually right where it should be—resting in a groove at the end of the thighbone (femur). When the knee bends and straightens, the patella moves straight up and down within the groove. Sometimes, the patella slides too far to one side or the other. When this occurs — such as after a hard blow or fall — the patella can completely or partially dislocate.

When the patella slips out of place — whether a partial or complete dislocation — it typically causes pain and loss of function. Even if the patella slips back into place by itself, it will still require treatment to relieve painful symptoms. Be sure to take your child to the doctor for a full examination to identify any damage to the knee joint and surrounding soft tissues.

kneecap function

(Left) The patella normally rests in a small groove at the end of the femur called the trochlear groove. (Right) As you bend and straighten your knee, the patella slides up and down within the groove.

Reproduced with permission from The Body Almanac. (c) American Academy of Orthopaedic Surgeons, 2003.

Cause

There are a several ways in which the kneecap can become unstable or dislocate. In many cases, the patella dislocates with very little force because of an abnormality in the structure of a child's knee.

  • A shallow or uneven groove in the femur can make dislocation more likely.
  • Some children's ligaments are looser, making their joints extremely flexible and more prone to patellar dislocation. This occurs more often in girls, and the problem may affect both knees.
  • Children with cerebral palsy and Down syndrome may have kneecaps that dislocate frequently due to imbalance and muscle weakness.
  • Rarely, children are born with unstable kneecaps causing dislocations at a very early age, often without pain.

patellar dislocation

Many things can cause patellar dislocation, such as a shallow groove in the femur or direct force on the knee joint.

Reproduced with permission from The Body Almanac. (c) American Academy of Orthopaedic Surgeons, 2003.

In children with normal knee structure, patellar dislocations are often the result of a direct blow or a fall onto the knee. This incidence is more common in high-impact sports, such as football.

Dislocations can occur without contact, as well. A common example is that of a right-handed baseball player who dislocates the right patella while swinging the bat. When the right foot is planted on the ground and the torso rotates during the swing, the patella lags behind, resulting in dislocation.

Symptoms

The symptoms associated with a patellar dislocation depend on how far out of place the patella has moved and how much damage occurred when it happened.

Some general symptoms your child may experience include:

  • Pain
  • Feeling the kneecap shift or slide out of the groove
  • Feeling the knee buckle or give way
  • Hearing a popping sound when the patella dislocates
  • Swelling
  • A change in the knee's appearance — the knee may appear misshapen or deformed
  • Apprehension or fear when running or changing direction.

Doctor Examination

If your child's patella has slid back into place, you should see your doctor as soon as possible. If your child's patella is still out of place, go to the emergency room.

Medical History and Physical Examination

During the examination, your doctor will ask you and your child about how the injury occurred and specific symptoms. Your doctor also will evaluate the range of motion, tenderness, and appearance of the knee.

Tests

Imaging tests can help your doctor diagnose patellar instability, as well as determine a treatment plan.

  • X-rays. These tests create clear pictures of bone. Your doctor may order x-rays to look for skeletal abnormalities in the knee, such as a shallow groove in the femur.
  • Magnetic resonance imaging (MRI) scans. These scans create better pictures of the soft structures surrounding the knee, like ligaments. An MRI is seldom necessary because the doctor can usually diagnose a dislocated patella through an examination and x-rays. However, if your doctor needs additional, more detailed images, he or she may order an MRI.

Sometimes a piece of bone or cartilage can dislodge or loosen when the patella dislocates. This can be seen on an x-ray or MRI scan.

x-ray of knee dislocation

In this x-ray of a bent knee taken from above, the patella is clearly out of alignment within the groove in the femur.
Reproduced with permission from Schepsis AA Patellar instability. Orthopaedic Knowledge Online Journal, 12/18/2003. Accessed February 2014.

Patellofemoral pain syndrome (PFPS) is a broad term used to describe pain in the front of the knee and around the patella, or kneecap. It is sometimes called "runner's knee" or "jumper's knee" because it is common in people who participate in sports—particularly females and young adults—but PFPS can occur in nonathletes, as well. The pain and stiffness caused by PFPS can make it difficult to climb stairs, kneel down, and perform other everyday activities.

Many things may contribute to the development of PFPS. Problems with the alignment of the kneecap and overuse from vigorous athletics or training are often significant factors.

Symptoms are often relieved with conservative treatment, such as changes in activity levels or a therapeutic exercise program.

Anatomy

Your knee is the largest joint in your body and one of the most complex. It is made up of the lower end of the femur (thighbone), the upper end of the tibia (shinbone), and the patella (kneecap).

Ligaments and tendons connect the femur to the bones of the lower leg. The four main ligaments in the knee attach to the bones and act like strong ropes to hold the bones together.

Normal knee anatomy

A healthy knee is made up of four main things: bones, cartilage, ligaments, and tendons.

Muscles are connected to bones by tendons. The quadriceps tendon connects the muscles in the front of the thigh to the patella. Segments of the quadriceps tendon—called the patellar retinacula—attach to the tib

ia and help to stabilize the patella. Stretching from your patella to your tibia is the patellar tendon.

Several structures in the knee joint make movement easier. For example, the patella rests in a groove on the top of the femur called the trochlea. When you bend or straighten your knee, the patella moves back and forth inside this trochlear groove.

A slippery substance called articular cartilage covers the ends of the femur, trochlear groove, and the underside of the patella. Articular cartilage helps your bones glide smoothly against each other as you move your leg.

Also aiding in movement is the synovium—a thin lining of tissue that covers the surface of the joint. The synovium produces a small amount of fluid that lubricates the cartilage. In addition, just below the kneecap is a small pad of fat that cushions the kneecap and acts as a shock absorber.

movement of the patella in the trochlear groove

(Left) The patella normally rests in a small groove at the end of the femur called the trochlear groove. (Right) As you bend and straighten your knee, the patella slides up and down within the groove.

Description

Patellofemoral pain syndrome occurs when nerves sense pain in the soft tissues and bone around the kneecap. These soft tissues include the tendons, the fat pad beneath the patella, and the synovial tissue that lines the knee joint.

In some cases of patellofemoral pain, a condition called chondromalacia patella is present. Chondromalacia patella is the softening and breakdown of the articular cartilage on the underside of the kneecap. There are no nerves in articular cartilage—so damage to the cartilage itself cannot directly cause pain. It can, however, lead to inflammation of the synovium and pain in the underlying bone.

Cause

Overuse

In many cases, PFPS is caused by vigorous physical activities that put repeated stress on the knee —such as jogging, squatting, and climbing stairs. It can also be caused by a sudden change in physical activity. This change can be in the frequency of activity—such as increasing the number of days you exercise each week. It can also be in the duration or intensity of activity—such as running longer distances.

Other factors that may contribute to patellofemoral pain include:

  • Use of improper sports training techniques or equipment
  • Changes in footwear or playing surface

Patellar Malalignment

Patellofemoral pain syndrome can also be caused by abnormal tracking of the kneecap in the trochlear groove. In this condition, the patella is pushed out to one side of the groove when the knee is bent. This abnormality may cause increased pressure between the back of the patella and the trochlea, irritating soft tissues.

Factors that contribute to poor tracking of the kneecap include:

  • Problems with the alignment of the legs between the hips and the ankles. Problems in alignment may result in a kneecap that shifts too far toward the outside or inside of the leg, or one that rides too high in the trochlear groove—a condition called patella alta.
  • Muscular imbalances or weaknesses, especially in the quadriceps muscles at the front of the thigh. When the knee bends and straightens, the quadriceps muscles and quadriceps tendon help to keep the kneecap within the trochlear groove. Weak or imbalanced quadriceps can cause poor tracking of the kneecap within the groove.

normal knee and knee of of alignment

(Left) In this MRI scan, the kneecap is normally aligned within the trochlear groove (arrows). (Right) Here, the kneecap has shifted out of the groove and is pulled toward the outside of the leg (circle).

Symptoms

The most common symptom of PFPS is a dull, aching pain in the front of the knee. This pain—which usually begins gradually and is frequently activity-related—may be present in one or both knees. Other common symptoms include:

  • Pain during exercise and activities that repeatedly bend the knee, such as climbing stairs, running, jumping, or squatting.
  • Pain on the front of the knee after sitting for a long period of time with your knees bent, such as one does in a movie theater or when riding on an airplane.
  • Pain related to a change in activity level or intensity, playing surface, or equipment.
  • Popping or crackling sounds in your knee when climbing stairs or when standing up after prolonged sitting.

Home Remedies

In many cases, patellofemoral pain will improve with simple home treatment.

Activity Changes

Stop doing the activities that make your knee hurt until your pain is resolved. This may mean changing your training routine or switching to low-impact activities—such as riding a stationary bike, using an elliptical machine, or swimming—that will place less stress on your knee joint. If you are overweight, losing weight will also help to reduce pressure on your knee.

The RICE Method

RICE stands for rest, ice, compression, and elevation.

  • Rest. Avoid putting weight on the painful knee.
  • Ice. Use cold packs for 20 minutes at a time, several times a day. Do not apply ice directly on skin.
  • Compression. To prevent additional swelling, lightly wrap the knee in an elastic bandage, leaving a hole in the area of the kneecap. Make sure that the bandage fits snugly and does not cause additional pain.
  • Elevation. As often as possible, rest with your knee raised up higher than your heart.

Medication

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen can help reduce swelling and relieve pain.

If your pain persists or it becomes more difficult to move your knee, contact your doctor for a thorough evaluation.

Doctor Examination

Physical Examination

During the physical examination, your doctor will discuss your general health and the symptoms you are experiencing. He or she will ask when your knee pain started and about the severity and nature of the pain (dull vs. sharp). Your doctor will also ask you what activities cause the pain to worsen.

To determine the exact location of the pain, your doctor may gently press and pull on the front of your knees and kneecaps. He or she may also ask you to squat, jump, or lunge during the exam in order to test your knee and core body strength.

checking patellar tracking

During the examination, your doctor will check your knee for problems in patellar tracking,
Reproduced with permission from JF Sarwark, ed: Essentials of Musculoskeletal Care, ed 4. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2010.

To help diagnose the cause of your pain and to rule out any other physical problems, your doctor may also check:

  • Alignment of the lower leg and the position of the kneecap
  • Knee stability, hip rotation, and range of motion of knees and hips
  • The kneecap for signs of tenderness
  • The attachment of thigh muscles to the kneecap
  • Strength, flexibility, firmness, and tone of the hips, front thigh muscles (quadriceps), and back thigh muscles (hamstrings)
  • Tightness of the heel cord and flexibility of the feet

Finally, your doctor may ask you to walk back and forth in order to examine your gait (the way you walk). He or she will look for problems with your gait that may be contributing to your knee pain.

Imaging Studies

X-rays. Usually, your doctor will be able to diagnose PFPS with just a physical examination. However, in most cases, he or she will also order an x-ray to rule out damage to the bones that make up the knee.

Magnetic resonance imaging (MRI) scans.This type of study provides clear images of the body’s soft tissues, such as ligaments, tendons, and muscles. Your doctor may order an MRI if, after a period of time, your symptoms do not improve with physical therapy and home exercise.

Bursae are small, jelly-like sacs that are located throughout the body, including around the shoulder, elbow, hip, knee, and heel. They contain a small amount of fluid, and are positioned between bones and soft tissues, acting as cushions to help reduce friction.

Pes anserine bursitis is an inflammation of the bursa located between the shinbone (tibia) and three tendons of the hamstring muscle at the inside of the knee. It occurs when the bursa becomes irritated and produces too much fluid, which causes it to swell and put pressure on the adjacent parts of the knee.

Pain and tenderness on the inside of your knee, approximately 2 to 3 inches below the joint, are common symptoms of pes anserine bursitis of the knee.

Location of pain from pes anserine bursitis

Pain from pes anserine bursitis is located on the inside of the knee, just below the joint.

Cause

Bursitis usually develops as the result of overuse or constant friction and stress on the bursa. Pes anserine bursitis is common in athletes, particularly runners. People with osteoarthritis of the knee are also susceptible.

Several factors can contribute to the development of pes anserine bursitis, including:

  • Incorrect training techniques, such as neglecting to stretch, doing excessive hill running, and sudden increases in mileage
  • Tight hamstring muscles
  • Obesity
  • An out-turning of the knee or lower leg
  • Osteoarthritis in the knee
  • Medial meniscus tear

Symptoms

The symptoms of pes anserine bursitis include:

  • Pain slowly developing on the inside of your knee and/or in the center of the shinbone, approximately 2 to 3 inches below the knee joint.
  • Pain increasing with exercise or climbing stairs

Doctor Examination

Your doctor will examine your knee and talk to you about your symptoms.

Symptoms of pes anserine bursitis may mimic those of a stress fracture, so an x-ray is usually required for diagnosis.

Osgood-Schlatter disease is a common cause of knee pain in growing adolescents. It is an inflammation of the area just below the knee where the tendon from the kneecap (patellar tendon) attaches to the shinbone (tibia).

Osgood-Schlatter disease most often occurs during growth spurts, when bones, muscles, tendons, and other structures are changing rapidly. Because physical activity puts additional stress on bones and muscles, children who participate in athletics — especially running and jumping sports  — are at an increased risk for this condition. However, less active adolescents may also experience this problem.

In most cases of Osgood-Schlatter disease, simple measures like rest, ice, over-the-counter medication, and stretching and strengthening exercises will relieve pain and allow a return to daily activities.

Osgood-Schlatter disease causes pain at the tibial tubercle — the bony bump where the patellar tendon attaches to the tibia (shinbone).

Osgood-Schlatter disease causes pain at the tibial tubercle — the bony bump where the patellar tendon attaches to the tibia (shinbone).

Description

The bones of children and adolescents possess a special area where the bone is growing called the growth plate. Growth plates are areas of cartilage located near the ends of bones. When a child is fully grown, the tibial tubercle covers the growth plate at the end of the tibia. The group of muscles in the front of the thigh (called the quadriceps) attaches to the tibial tubercle.

When a child is active, the quadriceps muscles pull on the patellar tendon which, in turn, pulls on the tibial tubercle. In some children, this repetitive traction on the tubercle leads to inflammation of the growth plate. The prominence, or bump, of the tibial tubercle may become very pronounced.

Symptoms

Painful symptoms are often brought on by running, jumping, and other sports-related activities. In some cases, both knees have symptoms, although one knee may be worse than the other.

  • Knee pain and tenderness at the tibial tubercle
  • Swelling at the tibial tubercle
  • Tight muscles in the front or back of the thigh

Doctor Examination

During the appointment, your doctor will discuss your child's symptoms and general health. He or she will conduct a thorough examination of the knee to determine the cause of the pain. This will include applying pressure to the tibial tubercle, which should be tender or painful for a child with Osgood-Schlatter disease. In addition, your doctor may also ask your child to walk, run, jump, or kneel to see if the movements bring on painful symptoms.

Your doctor may also order an x-ray image of your child's knee to help confirm the diagnosis or rule out any other problems.

Osgood-Schlatter disease inflamed tibial tubercle

In Osgood-Schlatter disease, the enlarged, inflamed tibial tubercle is nearly always tender when pressure is applied.

Anatomy

The knee is the largest and strongest joint in the body. It is made up of the lower end of the femur (thighbone), upper end of the tibia (shinbone), and the patella (kneecap). A smooth, slippery tissue called articular cartilage covers and protects the ends of the bones where they meet to form a joint.

The knee joint is filled with a clear fluid (synovial fluid) that acts as a lubricant to help reduce friction within the joint. Small fluid-filled sacs called bursa cushion the joint and help reduce friction between the muscles and other surrounding structures.

knee anatomy

The bones that make up the knee joint.

Cause

In adults, Baker’s cysts usually result from an injury or condition that causes swelling and inflammation inside the knee joint, such as:

  • Osteoarthritis
  • Rheumatoid arthritis
  • Meniscus tear
  • Anterior cruciate ligament (ACL) tear
  • Other conditions that damage the tissues inside the joint

In response to this inflammation, the knee produces excess synovial fluid, which travels behind the knee and accumulates in the popliteal bursa. The bursa then swells and bulges, forming a Baker's cyst.

In younger patients, Baker’s cysts often have no known cause.

Baker's cyst

A cyst forms when excess synovial fluid travels to the popliteal bursa at the back of the knee.

Symptoms

Some Baker’s cysts cause no symptoms and are only discovered incidentally during a physical exam or when an MRI scan is performed for some other reason. When symptoms do occur, they may include:

  • A feeling of fullness or a lump behind the knee
  • Knee pain
  • Stiffness or tightness at the back of the knee
  • Swelling in your knee and lower leg

If the cyst becomes very large, it can interfere with blood flow in the veins of your leg. This can cause pain, swelling, weakness, or even numbness if there is nerve compression. Very rarely, the cyst can even burst.

Sometimes the symptoms of a cyst may resemble those of a blood clot or deep vein thrombosis, a much more serious problem. If you have increasing pain and swelling in your calf, it is important to seek medical care right away to rule out a blood clot.

Doctor Examination

Medical History and Physical Examination

Your doctor will take a full medical history and ask you to describe your symptoms. He or she will want to know if you have had a previous knee injury.

Your doctor will then perform a careful examination of your affected knee, comparing it to your “normal” knee. During the exam, he or she will look for:

  • Swelling
  • Instability of the joint
  • A clicking or popping noise when you bend your knee
  • Joint stiffness and limited range of motion

Your doctor will also palpate (feel) the back of your knee where the cyst is located. Often, a cyst will become firm when the knee is fully extended and soft when the knee is bent.

Imaging Tests

Imaging tests may be ordered to help confirm the diagnosis and provide more information about your condition.

X-rays. X-rays provide images of dense structures, such as bone. Although a cyst cannot be seen on an x-ray, one may be ordered so that your doctor can look for narrowing of the joint space and other signs of arthritis in the joint.

normal and arthritic knee

(Left) In this x-ray of a normal knee, the space between the bones indicates healthy cartilage. (Right) This x-ray of an arthritic knee shows severe loss of joint space.

Ultrasound. This test uses sound waves to create images of structures inside the body. An ultrasound will help your doctor see the lump behind your knee in greater detail and determine whether it is solid or filled with fluid.

Magnetic resonance imaging (MRI) scans. These tests produce clear pictures of the body’s soft tissues. Your doctor may order an MRI scan to learn more about your cyst and to look for a meniscus tear or another underlying condition.

Baker's cyst

This MRI scan shows an area of fluid behind the knee, the characteristic location of a Baker’s cyst.

Treatment

Treatment for an ACL tear will vary depending upon the patient's individual needs. For example, the young athlete involved in agility sports will most likely require surgery to safely return to sports. The less active, usually older, individual may be able to return to a quieter lifestyle without surgery.

Nonsurgical Treatment

A torn ACL will not heal without surgery. But nonsurgical treatment may be effective for patients who are elderly or have a very low activity level. If the overall stability of the knee is intact, your doctor may recommend simple, nonsurgical options.

Bracing. Your doctor may recommend a brace to protect your knee from instability. To further protect your knee, you may be given crutches to keep you from putting weight on your leg.

Physical therapy. As the swelling goes down, a careful rehabilitation program is started. Specific exercises will restore function to your knee and strengthen the leg muscles that support it.

Surgical Treatment

Rebuilding the ligament. Most ACL tears cannot be sutured (stitched) back together. To surgically repair the ACL and restore knee stability, the ligament must be reconstructed. Your doctor will replace your torn ligament with a tissue graft. This graft acts as a scaffolding for a new ligament to grow on.

Grafts can be obtained from several sources. Often they are taken from the patellar tendon, which runs between the kneecap and the shinbone. Hamstring tendons at the back of the thigh are a common source of grafts. Sometimes a quadriceps tendon, which runs from the kneecap into the thigh, is used. Finally, cadaver graft (allograft) can be used.

There are advantages and disadvantages to all graft sources. You should discuss graft choices with your own orthopaedic surgeon to help determine which is best for you.

Because the regrowth takes time, it may be six months or more before an athlete can return to sports after surgery.

Procedure. Surgery to rebuild an anterior cruciate ligament is done with an arthroscope using small incisions. Arthroscopic surgery is less invasive. The benefits of less invasive techniques include less pain from surgery, less time spent in the hospital, and quicker recovery times.

Rehabilitation

Whether your treatment involves surgery or not, rehabilitation plays a vital role in getting you back to your daily activities. A physical therapy program will help you regain knee strength and motion.

If you have surgery, physical therapy first focuses on returning motion to the joint and surrounding muscles. This is followed by a strengthening program designed to protect the new ligament. This strengthening gradually increases the stress across the ligament. The final phase of rehabilitation is aimed at a functional return tailored for the athlete's sport.

Treatment

Nonsurgical Treatment

If you have injured just your posterior cruciate ligament, your injury may heal quite well without surgery Your doctor may recommend simple, nonsurgical options.

RICE. When you are first injured, the RICE method - rest, ice, gentle compression and elevation — can help speed your recovery.

Immobilization. Your doctor may recommend a brace to prevent your knee from moving. To further protect your knee, you may be given crutches to keep you from putting weight on your leg.

Physical therapy. As the swelling goes down, a careful rehabilitation program is started. Specific exercises will restore function to your knee and strengthen the leg muscles that support it. Strengthening the muscles in the front of your thigh (quadriceps) has been shown to be a key factor in a successful recovery.

Surgical Treatment

Your doctor may recommend surgery if you have combined injuries. For example, if you have dislocated your knee and torn multiple ligaments including the posterior cruciate ligament, surgery is almost always necessary.

Rebuilding the ligament. Because sewing the ligament ends back together does not usually heal, a torn posterior cruciate ligament must be rebuilt. Your doctor will replace your torn ligament with a tissue graft. This graft is taken from another part of your body, or from another human donor (cadaver). It can take several months for the graft to heal into your bone.

Procedure. Surgery to rebuild a posterior cruciate ligament is done with an arthroscope using small incisions. Arthroscopic surgery is less invasive. The benefits of less invasive techniques include less pain from surgery, less time spent in the hospital, and quicker recovery times.

Surgical procedures to repair posterior cruciate ligaments continue to improve. More advanced techniques help patients resume a wider range of activities after rehabilitation.

Rehabilitation

Whether your treatment involves surgery or not, rehabilitation plays a vital role in getting you back to your daily activities. A physical therapy program will help you regain knee strength and motion. If you had surgery, physical therapy will begin 1 to 4 weeks after your procedure.

How long it takes you to recover from a posterior cruciate ligament injury will depend on the severity of your injury. Combined injuries often have a slow recovery, but most patients do well over time.

If your injury requires surgery, it may be several weeks before you return to a desk job - perhaps months if your job requires a lot of activity. Full recovery typically requires 6 to 12 months.

Although it is a slow process, your commitment to therapy is the most important factor in returning to all the activities you enjoy.

Treatment

The treatment your doctor recommends will depend on a number of factors, including your age, symptoms, and activity level. He or she will also consider the type, size, and location of the injury.

The outer one-third of the meniscus has a rich blood supply. A tear in this "red" zone may heal on its own, or can often be repaired with surgery. A longitudinal tear is an example of this kind of tear.

In contrast, the inner two-thirds of the meniscus lacks a significant blood supply. Without nutrients from blood, tears in this "white" zone with limited blood flow cannot heal. Because the pieces cannot grow back together, symptomatic tears in this zone that do not respond to conservative treatment are usually trimmed surgically.

Nonsurgical Treatment

Many meniscus tears will not need immediate surgery. If your symptoms do not persist and you have no locking or swelling of the knee, your doctor may recommend nonsurgical treatment.

RICE. The RICE protocol is effective for most sports-related injuries. RICE stands for Rest, Ice, Compression, and Elevation.

  • Rest. Take a break from the activity that caused the injury. Your doctor may recommend that you use crutches to avoid putting weight on your leg.
  • Ice. Use cold packs for 20 minutes at a time, several times a day. Do not apply ice directly to the skin.
  • Compression. To prevent additional swelling and blood loss, wear an elastic compression bandage.
  • Elevation. To reduce swelling, recline when you rest, and put your leg up higher than your heart.

Nonsteroidal anti-inflammatory medications. Drugs such as aspirin and ibuprofen can help reduce pain and swelling.

Steroid injection. Your doctor may inject a corticosteroid medication into your knee joint to help eliminate pain and swelling.

Other nonsurgical treatment. Biologics injections, such as platelet-rich plasma, are currently being studied and may show promise in the future for the treatment of meniscus tears.

Surgical Treatment

If your symptoms persist with nonsurgical treatment, your doctor may suggest arthroscopic surgery.

Procedure.  Knee arthroscopy is one of the most commonly performed surgical procedures. In this procedure, the surgeon inserts a miniature camera through a small incision (portal) in the knee. This provides a clear view of the inside of the knee. He or she then inserts surgical instruments through two or three other small portals to trim or repair the tear.

Knee arthroscopy

Illustration and photo show a camera and instruments inserted through portals in a knee.

  • Partial meniscectomy.  In this procedure, the damaged meniscus tissue is trimmed away. This procedure typically allows for immediate weight bearing, and full range of motion soon after surgery.

    In this short surgical video, a degenerative meniscus tear is  smoothed down with a motorized shaver during a partial meniscectomy.

    • Meniscus repair.  Some meniscus tears can be repaired by suturing (stitching) the torn pieces together. Whether a tear can be successfully repaired depends upon the type of tear, as well as the overall condition of the injured meniscus. Because the meniscus must heal back together, recovery time for a repair is longer than for a meniscectomy.

    Close-up of partial meniscectomy

    Close-up of partial meniscectomy

    A torn meniscus repaired with sutures

    A torn meniscus repaired with sutures

    Once the initial healing is complete, your doctor will prescribe rehabilitation exercises. Regular exercise to restore your knee mobility and strength is necessary. You will start with exercises to improve your range of motion. Strengthening exercises will gradually be added to your rehabilitation plan.

    In many cases, rehabilitation can be carried out at home, although your doctor may recommend working with a physical therapist. Rehabilitation time for a meniscus repair is about 3 to 6 months. A meniscectomy requires less time for healing — approximately 3 to 6 weeks.

    Recovery

    Meniscus tears are extremely common knee injuries. With proper diagnosis, treatment, and rehabilitation, patients often return to their pre-injury abilities.

Treatment

Sometimes, a doctor discovers a discoid meniscus when evaluating the knee for a different problem. If the discoid meniscus is not causing any symptoms, then specific treatment for it may not be necessary.

When a discoid meniscus is causing pain, popping, or other symptoms, however, your orthopedic surgeon will probably recommend arthroscopic surgery.

Surgical Treatment

Knee arthroscopy is one of the most commonly performed orthopaedic surgical procedures.

During arthroscopy, the surgeon makes a few small incisions around the knee and inserts a small camera, called an arthroscope, into the joint. The camera displays pictures on a television screen, and the surgeon uses these images to guide miniature surgical instruments.

Most arthroscopic surgeries are done on an outpatient basis. Patients usually go home a few hours after the procedure.

Anesthesia. To prevent pain during the procedure, the patient is given anesthesia. There are different types of anesthesia: Local and regional types of anesthesia numb just parts of the body, and the patient remains awake. General anesthesia puts the patient to sleep. Most children are given general anesthesia for arthroscopic surgery.

Surgical Procedure. Treatment will depend upon the type of discoid meniscus.

  • Complete and incomplete discoid menisci with no tears are typically treated with saucerization, a procedure in which the meniscus is cut and re-shaped into a crescent.
  • If the discoid meniscus is also torn, the surgeon may perform a saucerization and then trim away the torn portion. Some tears can be repaired with stitches, rather than removed.
  • The hypermobile Wrisberg form of discoid meniscus is saucerized if necessary, then stabilized with stitches to sew the meniscus to the lining of the joint.

knee arthroscopy

During arthroscopy, your surgeon will insert the arthroscope and surgical instruments through small incisions called "portals."

Rehabilitation

After surgery, your doctor may put your child's knee in a brace or a soft bandage wrap. He or she may need to use crutches for a short period of time. Very young children may need a wheelchair for several weeks because they do not have the balance or strength to use crutches.

Once the initial healing is complete, your doctor may prescribe physical therapy exercises to restore strength and mobility. These may be done at home or with a physical therapist.

Recovery

Most patients return to normal daily activities after arthroscopy for a discoid meniscus. However, if the entire meniscus was removed, there is a risk for continued pain and, potentially, early arthritis.

Surgeons sometimes recommend that patients avoid sports that overstress the knee with cutting type movements. These include soccer, tennis, basketball, and football.

Treatment

The individual with a suspected multiple ligament injury needs a thorough examination by an experienced physician. Depending on the injury, the orthopaedic surgeon may call in other specialists such as a vascular surgeon or microsurgeon.

In contrast to treatment for single ligament tears, surgery for combined ligament tears is often performed soon after the injury. This is done even though early surgery — before inflammation has resolved — poses an increased risk of arthrofibrosis (a scar forming in the joint). More than one operation may be required when treating multiple ligament injuries.

Outcome

Results from multiple ligament surgery are not as consistent as single ligament injury.

In the past, a multiple ligament injury prevented people from returning to sports activities. Today, it is possible to return to high level sports, although there is no certainty of it.

Treatment

There is no cure for arthritis but there are a number of treatments that may help relieve the pain and disability it can cause.

Nonsurgical Treatment

As with other arthritic conditions, initial treatment of arthritis of the knee is nonsurgical. Your doctor may recommend a range of treatment options.

Lifestyle modifications. Some changes in your daily life can protect your knee joint and slow the progress of arthritis.

  • Minimize activities that aggravate the condition, such as climbing stairs.
  • Switching from high-impact activities (like jogging or tennis) to lower impact activities (like swimming or cycling) will put less stress on your knee.
  • Losing weight can reduce stress on the knee joint, resulting in less pain and increased function.

Physical therapy. Specific exercises can help increase range of motion and flexibility, as well as help strengthen the muscles in your leg. Your doctor or a physical therapist can help develop an individualized exercise program that meets your needs and lifestyle.

Assistive devices. Using devices such as a cane, wearing shock-absorbing shoes or inserts, or wearing a brace or knee sleeve can be helpful. A brace assists with stability and function, and may be especially helpful if the arthritis is centered on one side of the knee. There are two types of braces that are often used for knee arthritis: An "unloader" brace shifts weight away from the affected portion of the knee, while a "support" brace helps support the entire knee load.

Other remedies. Applying heat or ice, using pain-relieving ointments or creams, or wearing elastic bandages to provide support to the knee may provide some relief from pain.

Medications. Several types of drugs are useful in treating arthritis of the knee. Because people respond differently to medications, your doctor will work closely with you to determine the medications and dosages that are safe and effective for you.

  • Over-the-counter, non-narcotic pain relievers and anti-inflammatory medications are usually the first choice of therapy for arthritis of the knee. Acetaminophen is a simple, over-the-counter pain reliever that can be effective in reducing arthritis pain.Like all medications, over-the-counter pain relievers can cause side effects and interact with other medications you are taking. Be sure to discuss potential side effects with your doctor.
  • Another type of pain reliever is a nonsteroidal anti-inflammatory drug, or NSAID (pronounced "en-said"). NSAIDs, such as ibuprofen and naproxen, are available both over-the-counter and by prescription.
  • A COX-2 inhibitor is a special type of NSAID that may cause fewer gastrointestinal side effects. Common brand names of COX-2 inhibitors include Celebrex (celecoxib) and Mobic (meloxicam, which is a partial COX-2 inhibitor). A COX-2 inhibitor reduces pain and inflammation so that you can function better. If you are taking a COX-2 inhibitor, you should not use a traditional NSAID (prescription or over-the-counter). Be sure to tell your doctor if you have had a heart attack, stroke, angina, blood clot, hypertension, or if you are sensitive to aspirin, sulfa drugs, or other NSAIDs.
  • Corticosteroids (also known as cortisone) are powerful anti-inflammatory agents that can be injected into the joint. These injections provide pain relief and reduce inflammation; however, the effects do not last indefinitely. Your doctor may recommend limiting the number of injections to three or four per year, per joint, due to possible side effects.In some cases, pain and swelling may "flare" immediately after the injection, and the potential exists for long-term joint damage or infection. With frequent repeated injections, or injections over an extended period of time, joint damage can actually increase rather than decrease.
  • Disease-modifying anti-rheumatic drugs (DMARDs) are used to slow the progression of rheumatoid arthritis. Drugs like methotrexate, sulfasalazine, and hydroxychloroquine are commonly prescribed.In addition, biologic DMARDs like etanercept (Enbrel) and adalimumab (Humira) may reduce the body's overactive immune response. Because there are many different drugs today for rheumatoid arthritis, a rheumatology specialist is often required to effectively manage medications.
  • Viscosupplementation involves injecting substances into the joint to improve the quality of the joint fluid.
  • Glucosamine and chondroitin sulfate, substances found naturally in joint cartilage, can be taken as dietary supplements. Although patient reports indicate that these supplements may relieve pain, there is no evidence to support the use of glucosamine and chondroitin sulfate to decrease or reverse the progression of arthritis.In addition, the U.S. Food and Drug Administration does not test dietary supplements before they are sold to consumers. These compounds may cause side effects, as well as negative interactions with other medications. Always consult your doctor before taking dietary supplements.

Alternative therapies. Many alternative forms of therapy are unproven, but may be helpful to try, provided you find a qualified practitioner and keep your doctor informed of your decision. Alternative therapies to treat pain include the use of acupuncture, magnetic pulse therapy, platelet-rich plasma, and stem cell injections.

Acupuncture uses fine needles to stimulate specific body areas to relieve pain or temporarily numb an area. Although it is used in many parts of the world and evidence suggests that it can help ease the pain of arthritis, there are few scientific studies of its effectiveness. Be sure your acupuncturist is certified, and do not hesitate to ask about his or her sterilization practices.

Magnetic pulse therapy is painless and works by applying a pulsed signal to the knee, which is placed in an electromagnetic field. Like many alternative therapies, magnetic pulse therapy has yet to be proven.

Treatments such as platelet-rich plasma (PRP) and stem cell injections involve taking cells from your own body and re-injecting them into a painful joint.

PRP uses a component of your own blood, platelets, that have been separated from your blood, concentrated, and injected into your knee. The platelets contain “growth factors” thought to be helpful in reducing the symptoms of inflammation.

Stem cells are precursor cells that can also be taken from your own body and injected into your knee. Since they are basic cells, they may have potential to grow into new tissue and thus heal damaged joint surfaces.

While both treatments show promise, clinical studies have yet to confirm their value in treating osteoarthritis.

Surgical Treatment

Your doctor may recommend surgery if your pain from arthritis causes disability and is not relieved with nonsurgical treatment. As with all surgeries, there are some risks and possible complications with different knee procedures. Your doctor will discuss the possible complications with you before your operation.

Arthroscopy. During arthroscopy, doctors use small incisions and thin instruments to diagnose and treat joint problems.

Arthroscopic surgery is not often used to treat arthritis of the knee. In cases where osteoarthritis is accompanied by a degenerative meniscal tear, arthroscopic surgery may be recommended to treat the torn meniscus.

Cartilage grafting. Normal, healthy cartilage tissue may be taken from another part of the knee or from a tissue bank to fill a hole in the articular cartilage. This procedure is typically considered only for younger patients who have small areas of cartilage damage.

Synovectomy. The joint lining damaged by rheumatoid arthritis is removed to reduce pain and swelling.

Osteotomy. In a knee osteotomy, either the tibia (shinbone) or femur (thighbone) is cut and then reshaped to relieve pressure on the knee joint. Knee osteotomy is used when you have early-stage osteoarthritis that has damaged just one side of the knee joint. By shifting your weight off the damaged side of the joint, an osteotomy can relieve pain and significantly improve function in your arthritic knee.

Total or partial knee replacement (arthroplasty). Your doctor will remove the damaged cartilage and bone, and then position new metal or plastic joint surfaces to restore the function of your knee.

uni knee replacement implant and total knee replacement implant

Recovery

After any type of surgery for arthritis of the knee, there is a period of recovery. Recovery time and rehabilitation depends on the type of surgery performed.

Your doctor may recommend physical therapy to help you regain strength in your knee and to restore range of motion. Depending upon your procedure, you may need to wear a knee brace, or use crutches or a cane for a time.

In most cases, surgery relieves pain and makes it possible to perform daily activities more easily.

Treatment

Nonsurgical Treatment

Rest. Because shin splints are typically caused by overuse, standard treatment includes several weeks of rest from the activity that caused the pain. Lower impact types of aerobic activity can be substituted during your recovery, such as swimming, using a stationary bike, or an elliptical trainer.

Nonsteroidal anti-inflammatory medicines. Drugs like ibuprofen, aspirin, and naproxen reduce pain and swelling.

Ice. Use cold packs for 20 minutes at a time, several times a day. Do not apply ice directly to the skin.

Compression. Wearing an elastic compression bandage may prevent additional swelling.

Flexibility exercises. Stretching your lower leg muscles may make your shins feel better.

Supportive shoes. Wearing shoes with good cushioning during daily activities will help reduce stress in your shins.

Orthotics. People who have flat feet or recurrent problems with shin splints may benefit from orthotics. Shoe inserts can help align and stabilize your foot and ankle, taking stress off of your lower leg. Orthotics can be custom-made for your foot, or purchased "off the shelf."

Return to exercise. Shin splints usually resolve with rest and the simple treatments described above. Before returning to exercise, you should be pain-free for at least 2 weeks. Keep in mind that, when you return to exercise, it must be at a lower level of intensity. You should not be exercising as often as you did before, or for the same length of time.

Be sure to warm up and stretch thoroughly before you exercise. Increase training slowly. If you start to feel the same pain, stop exercising immediately. Use a cold pack and rest for a day or two. Return to training again at a lower level of intensity. Increase training even more slowly than before.

Surgical Treatment

Very few people need surgery for shin splints. Surgery has been done in very severe cases that do not respond to nonsurgical treatment. It is not clear how effective surgery is, however.

Prevention

There are things you can do to prevent shin splints.

Wear a proper fitting athletic shoe. To get the right fit, determine the shape of your foot using the "wet test." Step out of the shower onto a surface that will show your footprint, like a brown paper bag. If you have a flat foot, you will see an impression of your whole foot on the paper. If you have a high arch, you will only see the ball and heel of your foot. When shopping, look for athletic shoes that match your particular foot pattern.

In addition, make sure you wear shoes designed for your sport. Running long distances in court-type sneakers can contribute to shin splints.

Slowly build your fitness level. Increase the duration, intensity, and frequency of your exercise regimen gradually.

Cross train. Alternate jogging with lower impact sports like swimming or cycling.

Barefoot running. In recent years, barefoot running has gained in popularity. Many people claim it has helped to resolve shin splints. Some research indicates that barefoot running spreads out impact stresses among muscles, so that no area is overloaded. However, there is no clear evidence that barefoot running reduces the risk for any injury.

Like any significant change in your fitness regimen, a barefoot running program should be started very gradually. Begin with short distances to give your muscles and your feet time to adjust. Pushing too far, too fast can put you at risk for stress injuries. In addition, barefoot runners are at increased risk for cuts and bruises on their feet. Several brands of minimalist shoes with "toes" are available and these also require a slow working in period as your body adjusts to this different activity.

If your shin splints do not improve after rest and other methods described above, be sure to see a doctor to determine whether something else is causing your leg pain.

Treatment

Immediate Treatment

If your child's patella remains dislocated, go to the emergency room. To put the kneecap back in place, your doctor may give your child pain medication to relax his or her knee muscles, and then gently apply pressure to move the kneecap back into place. This process is called a "reduction."

Nonsurgical Treatment

  • Immobilization. Your doctor may recommend that your child wear a brace for 3 to 4 weeks. This stabilizes the knee while it heals.
  • Weightbearing. Because putting weight on the knee may cause pain and slow the healing process, your doctor may recommend using crutches for the first week or two after the injury.
  • Physical therapy. Once the knee has started to heal, your child's doctor will recommend physical therapy to help your child regain normal motion. Specific exercises will strengthen the thigh muscles holding the knee joint in place. Your child's commitment to the exercise program is important for a successful recovery. Typically, children return to activity 3 to 6 weeks after the injury.

Because a dislocation often damages knee tissue, the patella often remains looser, or more unstable, than it was before the injury. As a result, the patella may dislocate again. Recurrences also are common if the dislocation was caused by an irregularity in the knee structure. Ongoing exercises, such as cycling, can strengthen quadriceps muscles in the thigh and prevent future patellar dislocations.

Surgical Treatment

If your child's patella dislocates multiple times, or continues to be unstable despite therapy and bracing, surgery may be recommended to correct the problem. The type of surgery will depend on the cause of the unstable kneecap.

Surgical treatments often involve reconstructing the ligaments that hold the patella in place. This surgery is sometimes performed arthroscopically—using a tiny camera and miniature surgical instruments inserted through small incisions.

Repeated dislocation caused by a congenital or other bone deformity may require more complex surgical treatment.

Safe Return to Play

Once the knee has returned to full motion and strength, your doctor will likely allow your child to resume normal activities. A full return to more demanding sports may take more time. It is also important that the child feels comfortable and ready to resume activity.

Treatment

Medical treatment for PFPS is designed to relieve pain and restore range of motion and strength. In most cases, patellofemoral pain can be treated nonsurgically.

Nonsurgical Treatment

In addition to activity changes, the RICE method, and anti-inflammatory medication, your doctor may recommend the following:

Physical therapy. Specific exercises will help you improve range of motion, strength, and endurance. It is especially important to focus on strengthening and stretching your quadriceps since these muscles are the main stabilizers of your kneecap. Core exercises may also be recommended to strengthen the muscles in your abdomen and lower back.

Orthotics. Shoe inserts can help align and stabilize your foot and ankle, taking stress off of your lower leg. Orthotics can either be custom-made for your foot or purchased "off the shelf."

shoe inserts

Shoe inserts take stress off your lower leg by aligning your foot and ankle.
Reproduced with permission from JF Sarwark, ed: Essentials of Musculoskeletal Care, ed 4. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2010

Surgical Treatment

Surgical treatment for patellofemoral pain is very rarely needed and is done only for severe cases that do not respond to nonsurgical treatment. Surgical treatments may include:

Arthroscopy. During arthroscopy, your surgeon inserts a small camera, called an arthroscope, into your knee joint. The camera displays pictures on a television screen, and your surgeon uses these images to guide miniature surgical instruments.

  • Debridement. In some cases, removing damaged articular cartilage from the surface of the patella can provide pain relief.
  • Lateral release. If the lateral retinaculum tendon is tight enough to pull the patella out of the trochlear groove, a lateral release procedure can loosen the tissue and correct the patellar malalignment.

This short surgical video demonstrates an arthroscopic lateral release as seen from inside the knee. A lateral release may be performed as a single procedure or sometimes as part of a larger surgery to treat a painful or unstable kneecap.

Tibial tubercle transfer. In some cases, it may be necessary to realign the kneecap by moving the patellar tendon along with a portion of the tibial tubercle—the bony prominence on the tibia (shinbone).

A traditional open surgical incision is required for this procedure. The doctor partially or totally detaches the tibial tubercle so that the bone and the tendon can be moved toward the inner side of the knee. The piece of bone is then reattached to the tibia using screws. In most cases, this transfer allows for better tracking of the kneecap in the trochlear groove.

Prevention

Patellofemoral pain syndrome is usually fully relieved with simple measures or physical therapy. It may recur, however, if you do not make adjustments to your training routine or activity level. It is essential to maintain appropriate conditioning of the muscles around the knee, particularly the quadriceps and the hamstrings.

quad extension exercise

Leg extension exercises help to strengthen and stretch the quadriceps, the muscles in the front of the thigh.

There are additional steps that you can take to prevent recurrence of patellofemoral knee pain. They include:

  • Wearing shoes appropriate to your activities
  • Warming up thoroughly before physical activity
  • Incorporating stretching and flexibility exercises for the quadriceps and hamstrings into your warm-up routine, and stretching after physical activity
  • Increasing training gradually
  • Reducing any activity that has hurt your knees in the past
  • Maintaining a healthy body weight to avoid overstressing your knees.

Treatment

Athletes with pes anserine bursitis should take steps to modify their workout program so that the inflammation does not recur.

Other treatments include:

  • Rest. Discontinue the activity or substitute a different activity until the bursitis clears up.
  • Ice. Apply ice at regular intervals three or four times a day for 20 minutes at a time.
  • Anti-inflammatory medication. Aspirin and nonsteroidal anti-inflammatory medication (such as ibuprofen) may ease the pain and reduce the inflammation.
  • Injection. Your doctor may inject a solution of anesthetic and steroid into the bursa, which often provides prompt relief.
  • Physical therapy. Your doctor may recommend physical therapy for specific stretching exercises, and ice and ultrasound treatments.

If your symptoms continue, your orthopaedic surgeon may recommend surgical removal of the bursa. This is typically performed as an outpatient (same-day) procedure.

If putting weight on your leg causes discomfort after the procedure, your doctor will recommend using crutches for a short time. Normal activities can typically be resumed within 3 weeks of the procedure.

Treatment

Treatment for Osgood-Schlatter disease focuses on reducing pain and swelling. This typically requires limiting exercise activity until your child can enjoy activity without discomfort or significant pain afterwards. In some cases, rest from activity is required for several months, followed by a strength conditioning program. However, if your child does not have a large amount of pain or a limp, participation in sports may be safe to continue.

Your doctor may recommend additional treatment methods, including:

  • Stretching exercises. Stretches for the front and back of the thigh (quadriceps and hamstring muscles) may help relieve pain and prevent the disease from returning.
  • Nonsteroidal anti-inflammatory medication. Drugs like ibuprofen and naproxen reduce pain and swelling.
  • Ice.  Icing the inflamed area may reduce pain and swelling. Use cold packs for 20 minutes at a time, several times a day. Do not apply ice directly to the skin.

Standing quadriceps stretch.

Standing quadriceps stretch.

You should feel this stretch in the front of your thigh.
Tip:  Do not arch or twist your back.

Outcome

Most symptoms will completely disappear when a child completes the adolescent growth spurt, around age 14 for girls and age 16 for boys. For this reason, surgery is rarely recommended. However, the prominence of the tubercle will persist.

Treatment

Nonsurgical Treatment

Most Baker’s cysts will go away on their own. For cysts that do not disappear, initial treatment is always nonsurgical in nature and may include one or more of the following:

  • Observation. Your doctor may recommend simply observing the cyst over time to ensure that it does not grow larger and cause painful symptoms.
  • Activity modification. Decreasing your activity and avoiding high-impact activities that irritate the knee, such as jogging and aerobics, can help alleviate symptoms.
  • Nonsteroidal anti-inflammatory medications.  Drugs like ibuprofen and naproxen can help reduce pain and swelling.
  • Steroid injection. Your doctor may inject a corticosteroid medication into your knee joint to reduce inflammation.
  • Aspiration.  In this procedure, your doctor numbs the area around the cyst, then uses a needle to drain the excess fluid from the joint. Aspiration is often performed using ultrasound to guide the placement of the needle.

Surgical Treatment

Surgical treatment for a Baker’s cyst is rarely needed. However, it may be recommended if you have painful symptoms that are not relieved with nonsurgical treatment or if your cyst returns repeatedly after aspiration.

Arthroscopy. In this procedure, your doctor makes tiny incisions under anesthesia, then inserts a small camera called an arthroscope into the knee joint. The camera displays images on a video screen and your doctor uses these images to guide miniature surgical instruments.

Arthroscopy is used to treat conditions inside the knee, such as meniscus tears, that may give rise to a Baker’s cyst.

knee arthroscopy

Photo shows a camera and instruments inserted through portals in the knee.

Excision. For large cysts or those that are causing nerve and vascular problems, your doctor may perform an open surgical procedure to excise (remove) the entire cyst.

Recovery

It is very important to follow your recovery instructions to prevent the recurrence of a Baker's cyst.

Early movement. If your cyst has been aspirated or if you have had arthroscopic surgery, you will most likely be allowed to walk right after the procedure, but you should avoid strenuous activity during your recovery.

Bracing. Your doctor may recommend that you wear a knee brace for several weeks after surgery to immobilize your knee.

Physical therapy. Specific exercises will help improve range of motion and strengthen the muscles around the knee.

The time it takes to recover from surgery varies from patient to patient, depending on whether the underlying condition in the joint was treated during the procedure. Most patients can expect a return to full activity around 4 to 6 weeks after surgery.