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What's wrong with my knee?

Wondering what’s wrong with your knee? Your knee is one of the hardest working joints in your body, so it’s no wonder most of us will experience knee pain at some point in our lives.

What causes knee pain?

Although knee pain will often go away by itself, when knee pain strikes it can be quite distressing and disruptive to your daily routine.

Different types of knee pain - from constant to sudden knee pain, to pain in both knees or just one - can all be signs of different problems. We've highlighted seven of the most common causes of knee pain and stiffness along with their symptoms, and given advice on how to rest your knee and when to seek medical advice.

Here are 7 common conditions that can often cause knee pain:

1. Osteoarthritis

As we age, the cartilage in our knees can become worn and it can begin to deteriorate. When this ‘wear and tear’ process happens, osteoarthritis can occur, which is a greater risk in older age.

The pain from osteoarthritis stems from the loss of cartilage in the knee which will often feel worse during physical activities.

There are various other types of arthritis, including rheumatoid arthritis, but osteoarthritis is the most common type.

Common symptoms:

  • Swelling
  • Stiffness
  • Pain when bending your knee
  • A cracking sound on movement

2. Bursitis

The bursa is a fluid-filled sac that’s located near to your main joints. Any joint can become affected with bursitis, including in your knees, hips and shoulders.

The main role of the bursa in your knee is to reduce friction between your bones and tendons.

Repetitive movements and overuse of your knee, such as kneeling, can aggravate the bursa causing sore knees and swelling. This pain can be managed by rest and painkillers. However if your problems persist, you should seek advice from a medical professional.

Common symptoms:

  • Pain
  • Swelling
  • Warmth
  • Tenderness

3. Patella Tendonitis

Patella tendonitis, also called jumper’s knee, is an injury that occurs from overuse causing pain in the front of the knee.

It’s common in sports, such as basketball, football and running, which involve jumping or stopping suddenly.

If you frequently put your knee through strenuous activities, you could be at risk of developing jumper’s knee. Not warming up properly before exercising and being overweight can be other contributing factors.

Common symptoms

A sharp, throbbing pain when exercising, swelling, bruising, redness and day-to-day discomfort.

  • Swelling
  • Bruising
  • Redness
  • Day-to-day discomfort

4. ACL Injury

The most common ligament injury is damage to your anterior cruciate ligament (ACL), which is responsible for keeping your knee stable. This type of injury is often sports-related.

If your ACL does become stretched or strained, it most likely won’t go back to a normal level of function on its own.

If you suspect you’ve injured your ACL it’s important to get a quick diagnosis to determine the extent of the injury.

Common symptoms:

  • Swelling
  • Knee instability
  • Knee giving way
  • A popping sound

5. Meniscus tear

The meniscus is a piece of cartilage that acts as a cushion between your thighbone and shinbone. You’re more at risk of damaging this part of your knee if you play sports, especially sports which involve turning or stopping suddenly, such as football, hockey, basketball and tennis.

If you’re an older person and suspect a meniscus tear may be the source of your pain, it could be due to a chronic condition, such as arthritis. This type of degeneration or ‘wear and tear’ can cause the meniscus to become damaged and weakened, meaning it’s more liable to tearing.

Common symptoms:

  • Pain
  • Swelling
  • A popping sound
  • Instability

6. Runner’s Knee

When it comes to patellofemoral pain syndrome (PFPS), also known as runner’s knee, the clue is in the name. It’s very common among runners.

The impact of running can take its toll on the knee, resulting in either sharp and sudden pain, or a dull ache.

Weak or unbalanced thigh muscles can bring on runner’s knee, as can tight hamstrings.

Applying ice and stretching can help to reduce symptoms. However if the pain is severe or the knee is swollen, then it’s always a good idea to have it examined by a healthcare professional.

Common symptoms

  • Pain at the front of your knee or at the back of your kneecap
  • Pain during physical activities
  • Swelling
  • A cracking sound
  • Day-to-day discomfort

7. Baker’s Cyst

A Baker’s cyst is a fluid-filled sac that can develop at the back of the knee.

It can be due to a sports-related injury or a blow to the back of the knee; but it can also occur if you have osteoarthritis.

The good news is that a Baker’s cyst will usually clear up on its own. If it does persist and is making day-to-day activities difficult, then you should have it looked at by your GP who can refer you for further tests if needed.

Common symptoms

  • Knee pain
  • Stiffness and pain bending knees
  • Inflexibility
  • Fluid-filled swelling at the back of the knee
  • Locking of the knee
  • Clicking of the knee

What to do for knee pain relief 

Whatever the cause of the pain in your knee joint, there are certain things you can do to help manage your discomfort.

If you have mild to moderate knee pain and stiffness, you can try to ease your symptoms by limiting the amount of weight you place on your knees. For example, try not to stand for a long period of time.

With that in mind, it’s also important to balance rest with adequate exercise. Activities, such as walking, swimming and yoga, can help to improve strengthen, increase flexibility and reduce knee stiffness.

Another option is to use the RICE method:

  • Rest – taking the appropriate amount of rest
  • Ice – applying ice to reduce swelling
  • Compression - compressing or wrapping the knee with a bandage
  • Elevate – keep your knee elevated on a pillow when lying down.

Knee pain treatment

Painkillers can also be taken to help to manage knee pain, as can anti-inflammatories which can reduce the inflammation that’s causing your pain and stiffness.

However, if your knee pain is new, ongoing or severe, it’s always best to seek advice from a healthcare professional.

Getting an early diagnosis can not only help to identify the cause of your pain, but it can prevent you from further damaging your knee in the long term.

Ultimately, the earlier you have your pain checked out, the quicker you can get back to normal.