Baker's Cyst Causes, Symptoms, Diagnosis, Treatment, Prevention, Home Remedies

Baker's Cyst Causes, Symptoms, Diagnosis, Treatment, Prevention, Home Remedies

What is a Baker’s cyst?
Baker's Cyst

A Baker’s cyst is also known as a popliteal cyst or synovial cyst. It is a soft, fluid-filled lump that forms on the back of the knee. It is named after a doctor called William Baker who first described this condition in 1877. The lump is sometimes mistaken for a blood clot, but it is not a blood clot. A Baker’s cyst usually develops because of damage to the knee. When the structures in or around the joint are damaged, the knee produces more fluid.

Although a Baker's cyst may cause swelling and make you uncomfortable, treating the probable underlying problem usually provides relief.

What causes a Baker’s cyst?

A primary Baker's cyst

A Baker's cyst may develop just behind an otherwise healthy knee joint. This type of cyst is sometimes referred to as a primary or idiopathic Baker's cyst. It usually develops in younger people and children.

It is thought that in this type of Baker's cyst there is a connection between the knee joint and the popliteal bursa behind the knee. This means that synovial fluid from inside the joint can pass into the popliteal bursa and a Baker's cyst can form.

A secondary Baker's cyst

Sometimes a Baker's cyst can develop if there is an underlying problem within the knee, such as arthritis (including osteoarthritis and rheumatoid arthritis), or a tear in the meniscal cartilage that lines the inside of the knee joint. This type of Baker's cyst is the most common. It is sometimes referred to as a secondary Baker's cyst.

In a secondary Baker's cyst, the underlying problem within the knee joint causes too much synovial fluid to be produced within the joint. As a result of this, the pressure inside the knee increases. This has the effect of stretching the joint capsule. The joint capsule bulges out into the back of the knee, forming the Baker's cyst that is filled with synovial fluid.

Who gets a Baker's cyst?

A Baker's cyst most commonly occurs in children aged 4 to 7 years and in adults aged 35 to 70 years. However, Baker's cysts are much more common in adults than in children. You are more likely to develop a Baker's cyst if you have an underlying problem with your knee.

Arthritis is the most common condition associated with Baker's cysts. This can include various different types of arthritis, such as osteoarthritis (most common), rheumatoid arthritis, psoriatic arthritis and gout.

Baker's cysts may also develop if you have had a tear to the meniscus or to one of the ligaments within the knee, or if you have had an infection within the knee joint.

What are the symptoms of a Baker’s cyst?

Sometimes there is only slight pain to signal a Baker’s cyst. There can still be pain in the knee from the initial damage that caused the Baker’s cyst. You may notice a soft lump that sticks out from the back of the knee. Any strain can cause this lump or the knee to swell in size.

Baker's Cyst Causes, Symptoms, Diagnosis, Treatment, Prevention, Home Remedies
Baker's Cyst

A large cyst may cause some discomfort or stiffness, but there are often no symptoms. There may be a painless or painful swelling behind the knee.

The cyst may feel like a water-filled balloon. Sometimes, the cyst may break open (rupture), causing pain, swelling, and bruising on the back of the knee and calf.

It is important to know whether pain or swelling is caused by a Baker's cyst or a blood clot. A blood clot (deep venous thrombosis) can also cause pain, swelling, and bruising on the back of the knee and calf. A blood clot may be dangerous and requires immediate medical attention.

When to see a doctor

If you're experiencing pain and swelling behind your knee, see your doctor to determine the cause. Though unlikely, a bulge behind your knee may be a sign of a more serious condition rather than a fluid-filled cyst.

How is a Baker’s cyst diagnosed?

You need a professional medical exam to diagnose a Baker’s cyst. Here are the ways a doctor would diagnose a Baker’s cyst:

  • Taking a medical history, including information on previous injury to the knee.
  • Taking an X-ray – You will not see the lump through the X-ray, but it will help determine if there is arthritis present in the knee. This can be the cause of the Baker's cyst.
  • Ordering magnetic resonance imaging (MRI) scans – An MRI uses magnetic waves instead of X-rays to show images.
  • Ordering an ultrasound test – Ultrasound uses sound waves to determine if the lump is solid or filled with fluid.

Baker's Cyst Causes, Symptoms, Diagnosis, Treatment, Prevention, Home Remedies
Baker's Cyst

How is a Baker’s cyst treated?

Treatment of a Baker’s cyst usually starts with nonsurgical options. Surgery may be suggested if it does not improve.

Nonsurgical treatment for Baker's Cyst

Here are some ways to treat a Baker’s cyst without surgery:

  • Rest and elevation of the leg
  • Ice and anti-inflammatory medications like ibuprofen
  • Avoiding activities that strain the knee
  • Treating the initial damage to the knee
  • Going to physical therapy
  • Draining the cyst with a needle
  • Getting a steroid injection

Surgical treatment for Baker's Cyst

When you have a serious pain in your knee, or you are not able to move your knee very much, your doctor may suggest surgery. The surgeon may only need to make a small cut on the knee. Surgery will only relieve the problem if the initial cause of the Baker's cyst is treated as well.

What will my recovery be like after surgery?

Your ability to recover and how long it takes you to recover can be different for each patient.  Here are some things to expect:

  • You may feel a little tenderness and throbbing in the knee after surgery.
  • You may go back to work and continue daily activities when you feel you are able to and your doctor has cleared you to do this.
  • Be sure to keep the knee propped up for a few days after surgery to lessen swelling or pain.
  • Avoid strenuous activities.
  • There will be a follow up appointment requested by your doctor several days after your surgery.
  • You may receive pain medications after your surgery. Take medications as instructed by your surgeon.
  • You should be able to drive two weeks after surgery.
  • The doctor may have you go to physical therapy to continue the healing process of the knee.

Can a Baker’s cyst be prevented?

Knee joints are prone to injury during sporting activities. Preventing knee trauma can reduce the risk of Baker’s cyst developing in the first place or recurring after treatment. Suggestions include:
  • Warm up the knee joints and soft tissue by gently going through the motions of your sport or activity and stretching the muscles.
  • Wear supportive footwear appropriate to your activity.
  • Try to turn on the balls of your feet, rather than through your knees.
  • Cool down after sport by performing gentle and sustained stretches.
  • If you injure your knee, stop your activity immediately, apply ice packs to treat the swelling and seek medical advice.

Home Remedies for Baker's Cyst

If your doctor determines that arthritis is causing the cyst, he or she may advise you to take some or all of the following steps:

Follow the R.I.C.E. principles. These letters stand for rest, ice, compression and elevation. Rest your leg. Ice the inflamed area. Compress your knee with a wrap, sleeve or brace. And elevate your leg when possible, especially at night.

Try over-the-counter pain-relieving medications. Drugs such as ibuprofen (Advil, Motrin IB, others), naproxen (Aleve, others), acetaminophen (Tylenol, others) and aspirin can help relieve pain. Follow the dosing instructions on the package. Don't take more than the recommend dosage.

Scale back your physical activity. Doing so will reduce irritation of your knee joint. Your doctor can offer you guidance on how long you need to reduce your activity levels, and he or she may be able to suggest alternative forms of exercise you can do in the meantime.

Complications of Baker’s cyst

A person may be less inclined to seek medical help for Baker’s cyst if the symptoms are mild, which they generally are. However, if left untreated, complications can include:
  • The cyst continues to grow, causing the symptoms to worsen.
  • The cyst may extend down into the calf muscles (dissection).
  • The cyst can burst and cause bruising on the ankle of the affected leg, due to leaked fluid.
The symptoms of calf dissection and cyst rupture are similar to those caused by inflammation of veins, which may make diagnosis difficult and delay treatment. It is important to seek medical advice, as more serious but less common problems may present in a similar way. These may include a tumour or popliteal artery aneurysm.

Outlook (Prognosis)

A Baker's cyst will not cause any long-term harm, but it can be annoying and painful. The symptoms of Baker's cysts usually come and go.

Long-term disability is rare. Most people improve with time or arthroscopic surgery.