Introduction
Iliotibial band (ITB) syndrome is an overuse problem that is
often seen in bicyclists, runners, and long-distance walkers. It causes
pain on the outside of the knee just above the joint. It rarely gets so
bad that it requires surgery, but it can be very bothersome. The
discomfort may keep athletes and other active people from participating
in the activities they enjoy.
This guide will help you understand
- how ITB syndrome develops
- how the condition causes problems
- what treatment options are available
Anatomy
What is the ITB, and what does it do?
The ITB is actually a long tendon. (Tendons connect muscles to bone.) It attaches to a short muscle at the top of the pelvis called the tensor fascia lata. The ITB runs down the side of the thigh and connects to the outside edge of the tibia
(shinbone) just below the middle of the knee joint. You can feel the
tendon on the outside of your thigh when you tighten your leg muscles.
The ITB crosses over the side of the knee joint, giving added stability
to the knee.
The lower end of the ITB passes over the outer edge of the lateral femoral condyle, the area where the lower part of the femur
(thighbone) bulges out above the knee joint. When the knee is bent and
straightened, the tendon glides across the edge of the femoral condyle.
A bursa is a fluid-filled sac that cushions body tissues from friction. These sacs are present where muscles or tendons glide against one another. A bursa rests between the femoral condyle and the ITB.
Normally, this bursa lets the tendon glide smoothly back and forth
over the edge of the femoral condyle as the knee bends and straightens.
Related Document: A Patient's Guide to Knee Anatomy
Causes
How does ITB syndrome develop?
The ITB glides back and forth over the lateral femoral condyle as
the knee bends and straightens. Normally, this isn't a problem. But the
bursa between the lateral femoral condyle and the ITB can become irritated and inflamed if the ITB starts to snap over the condyle with repeated knee motions such as those from walking, running, or biking.
People often end up with ITB syndrome from overdoing their activity.
They try to push themselves too far, too fast, and they end up running,
walking, or biking more than their body can handle. The repeated strain
causes the bursa on the side of the knee to become inflamed.
Some experts believe that the problem happens when the knee bows
outward. This can happen in runners if their shoes are worn on the
outside edge, or if they run on slanted terrain. Others feel that
certain foot abnormalities, such as foot pronation, cause ITB syndrome. (Pronation of the foot occurs when the arch flattens.)
Recently, health experts have found that runners with a weakened or fatigued gluteus medius
muscle in the hip are more likely to end up with ITB syndrome. This
muscle controls outward movements of the hip. If the gluteus medius
isn't doing its job, the thigh tends to turn inward. This makes the
knee angle into a knock-kneed position. The ITB becomes tightened against the bursa on the side of the knee. This is also called a valgus deformity of the knee.
People with bowed legs may also be at risk of developing ITB
syndrome. The outward angle of the bowed knee makes the lateral femoral
condyle more prominent and can make the snapping worse. This condition
is also called a varus deformity of the knee.
Symptoms
What does ITB syndrome feel like?
The symptoms of ITB syndrome
commonly begin with pain over the outside of the knee, just above the
knee joint. Tenderness in this area is usually worse after activity. As
the bursitis grows worse, pain may radiate up the side of the thigh and
down the side of the leg. Patients sometimes report a snapping or
popping sensation on the outside of the knee.
Diagnosis
How will my doctor know it's ITB syndrome?
The diagnosis of ITB syndrome can usually be made without any
complicated tests. Your doctor will take a history of the problem and
ask about any other injuries that may have occurred in the past. X-rays
may be taken to make sure that there are no other injuries that could
be adding to the problem. Generally, no swelling is visible. The
snapping sensation usually cannot be heard.
Pain on the outside of the knee can be caused from conditions other
than ITB syndrome. Your doctor will perform an examination of the knee
and will look at your entire leg. You may want to take the shoes that
you use to run or walk with you to your appointment.
If there is doubt about the diagnosis, or you are still having
problems after reasonable attempts have been made to decrease the
symptoms, a magnetic resonance imaging (MRI) scan may be
suggested by your doctor. An MRI scan is a special test that uses
magnetic waves to create images of the soft tissues inside and around
the knee. Regular X-rays only show the bones around the knee. The MRI
can show if there are problems with the soft tissues such as the
cartilage and ligaments.
Treatment
What can be done for the condition?
Nonsurgical Treatment
Most cases of ITB syndrome can be treated with simple measures. At
first, heat, ice, and ultrasound may be used to help calm pain and
inflammation.
Your doctor may prescribe physical therapy, where the problems that
are causing your symptoms will be evaluated and treated. Stretching and
strengthening exercises may be used in combination with a knee brace,
kneecap taping, or shoe inserts to improve muscle balance and joint
alignment of the hip and lower limb. Your physical therapist will
probably ask you about your sport activities and may give you tips on
your warm up and training schedule, footwear, and choices of terrain.
If your symptoms continue, your doctor may suggest an injection of cortisone
into the bursa. Cortisone is a powerful anti-inflammatory medication
that may help reduce the inflammation and take away the pain.
Surgery
Surgery is rarely needed to correct ITB problems. Surgery consists
of removing the bursa and releasing, or lengthening, the ITB just
enough so that the friction is reduced when the knee is bent and
straightened.
Rehabilitation
What should I expect after treatment?
Nonsurgical Rehabilitation
If your treatment is nonsurgical, you should be able to return to
normal activity within four to six weeks. You may work with a physical
therapist during this time. A key element of treatment is your training
schedule. Your therapist can work with you to adjust the distance you
run, your footwear, and the running surfaces you choose.
Foot orthotics may be recommended to improve foot and lower limb
alignment. Wearing orthotics in your shoes may allow you to resume
normal walking immediately, but you should probably cut back on more
vigorous activities for several weeks to allow the inflammation and
pain to subside.
Strengthening and stretching exercises are chosen to correct muscle
imbalances, such as weakness in the gluteus medius muscle or tightness
in the ITB.
Treatments such as ultrasound, friction massage, and ice may be used
to calm inflammation in the ITB. Therapy sessions sometimes include iontophoresis,
which uses a mild electrical current to push anti-inflammatory medicine
to the sore area. This treatment is especially helpful for patients who
can't tolerate injections.
After Surgery
If you've undergone surgery, you and your surgeon will need to come
up with a plan for your rehabilitation. You will have a period of rest,
which may involve using crutches. You will also need to start a careful
and gradual exercise program. Patients often work with physical
therapists to direct the exercises for their rehabilitation program.
The therapist's goal is to help you keep your pain under control,
improve muscle and joint alignment, and return you to your sport or
activity without additional problems. When you are well under way,
regular visits to your therapist's office will end. The therapist will
continue to be a resource, but you will be in charge of doing your
exercises as part of an ongoing home program.
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