Knee Symptoms

Written By: Chloe Wilson, BSc(Hons) Physiotherapy
Reviewed by: KPE Medical Review Board

Common knee symptoms

Knee symptoms vary greatly depending on what is going on in and around the knee joint. There may be burning knee pain, sharp pain, instability, stiffness or difficulty with certain activities.

Each of these indicates different knee problems, and by thinking about what we feel, we can work out what is wrong and what to do to treat it.

Knee symptoms may indicate a fairly minor problem such as cartilage irritation or a minor ligament sprain, or they may be a sign of a more serious problem such as advanced arthritis or a ligament tear.

Different injuries will produce different knee symptoms. It may even be that the problem isn’t in the knee itself but that the pain is referred from somewhere else, such as the lower back. 

Common Knee Symptoms

Here we will look at the most common symptoms associated with knee pain and how to use those symptoms to work out what is wrong. From there, you can find the best way to treat your knee pain and stop it from coming back. 

Think about your knee symptoms. Are there particular activities when you really notice the pain or things you just don't like to do anymore because it hurts too much?
Does your knee make strange noises?
Does it look slightly different to the other knee?

Let's look at the most common knee symptoms and what they mean.

It is very common to get knee pain from running due to the forces going through the knee joint

Forces up to 550% body weight go through the joint when running. Running knee pain is usually due to either training errors, poor biomechanics or muscle imbalance.

In the Running Knee Pain diagnosis section, we look at why people get pain when they run, and how to prevent and treat this common problem. 

Thinking about your noisy knees can help you make a knee pain diagnosis

Knees sometimes make strange, disconcerting noises e.g. a sudden pop or a persistent clicking, grinding or crunching. Sometimes it's painful, other times not.

In the Noisy Knee Pain section we look at the possible causes, how to tell which one is causing your knee symptoms and how to treat them.

Knee pain on stairs is a common problem

Stairs often cause problems for people with knee pain, particularly coming down stairs. The force going through the knee cap when you come down stairs is 3.5x bodyweight.

Find out more about the most common causes of knee pain going down stairs to help with knee pain diagnosis, and how you can treat and prevent this common problem.

Knee locking usually indicates that something is getting stuck inside the joint and blocking it from moving normally

Knee locking occurs when something gets stuck in the joint, stopping you moving the knee. In most cases, it stops you being able to straighten the knee. You often have to wiggle the knee around before it will then move.

In the knee locking section we look at all the possible causes for the knee locking up, the associated symptoms and what you can do to treat them.

Swelling is a common problem with knee pain.  The location and severity of the swelling helps to make an accurate knee pain diagnosis

Virtually any knee problem may be accompanied by swelling, but different types of swelling lead to different knee pain diagnosis e.g. whether it comes on suddenly or builds up gradually.

In the knee swelling section we look at the most common causes of swelling, what they mean, commonly associated knee symptoms and how to treat them.

Calf muscle cramps can be caused by a number of different things

Muscle cramp is a common problem, particularly during or after exercise, or at night time. It can been extremely painful and whilst the cramping may only last for a few minutes, the calf may remain painful for a few hours or even days.

You can find out all about the most common causes of cramp in the lower leg including diagnosis, symptoms and treatment in the calf cramps section.

Burning knee pain is a common knee symptoms and may indicate a problem in the joint or from neural irritation.

Burning knee pain usually indicates that there is swelling inside the knee joint. This may be from a medical condition or an injury. In some cases it may be a sign of a problem elsewhere such as nerve compression or an underlying medical condition.

In the burning knee pain section we look at all the possible causes, associated knee symptoms, how to identify which you have and if it's serious.

Sharp knee pain is a common symptom usually associated with either a problem in the knee bones or surrounding nerves

A sudden, sharp pain in the knee usually indicates one of two things. Either something is getting squashed e.g. bone or soft tissue, or there is a problem in one of the nerves. The pain may be localised to the knee or spread down the leg.

In the sharp knee pain section we look at the possible causes, how they present and what activities are typically affected.

Knee stiffness may develop as a result of an injury or a medical condition. It may develop suddenly or gradually and often fluctuates.  Stiffness when you first wake up that settles once you’re moving about is a classic feature of Osteoarthritis, which is most common in the over 50’s.

In the stiff knee section, we look at the most common causes of knee stiffness, how to make an accurate knee pain diagnosis, and the most effective treatment options.

A great deal of force goes through the knee when we do any activities with a bent knee e.g.squatting down places a force seven times body weight through the knee.  There may be a problem inside the knee joint or in one of the surrounding soft tissues. 

You can find out about the most common causes and how to treat them in the Knee Pain When Bending section.

Pain When Sitting

Knee Pain Diagnosis looks at symptoms like pain when sitting for long periods to help you work out what is causing your knee pain.

Some knee symptoms tend to get worse with prolonged inactivity e.g. office workers sitting for long periods.  The pain may start while you are sitting or when you first get up. The most common causes are:
Runners Knee: causes pain and stiffness at the front of the knee
Arthritis: changes in the bone caused by wear and tear or inflammation
Osgood Schlatters: common in adolescents, particularly after a growth spurt. 

Pain When Kneeling

Thinking about your specific symptoms helps make an accurate diagnosis eg do you get knee pain when you are kneeling down?

Kneeling puts pressure through the front of the knee and primarily aggravates three conditions: 

Housemaids Knee: a common problem for people who spend long periods kneeling e.g. carpet layers
Osgood Schlatters: common in adolescents, particularly after a growth spurt.  
Arthritis: wear and tear or sometimes inflammation. Most common over the age of 50

Thinking about where your knee symptoms are is a great way to work out what is wrong with your knee

Another option is to think about where the majority of your knee symptoms are. There may be pain at the front of the knee, swelling behind the knee, discomfort on the side of the knee or below the joint or it may be the kneecap that is causing problems.

Visit the knee pain diagnosis section to find out how to use the location of your pain to work out what your knee symptoms mean. 

Bony Lump 

A lump below the kneecap often indicates Osgood Schlatter Disease. Image source

A bony lump just below the kneecap is a classic sign of Osgood Schlatters. This condition is common in teenagers and young adults particularly after a growth spurt. Tension on the tendon just below the kneecap damages the bone, which often results in a hard lump on the front of the shin.

Find out more about the common causes, knee symptoms, diagnosis and treatment options in the Osgood Schlatter section.

Knee Gives Way

This is when the knee buckles underneath you without you being able to control it. You may feel unsteady or even stumble or fall to the ground. It usually indicates a
1) Ligament injury: usually caused by sudden twisting, a force through the knee or the knee bending backwards the wrong way
2) Meniscus tear: often makes the knee feel unstable and can occasionally cause the knee to give way

Find out more about each of these by using the links above to make an accurate knee pain diagnosis.

Severe knee pain can be extremely concerning and unpleasant. It is often accompanied by other symptoms such as swelling, instability, redness and an obvious deformity. The pain may come on very suddenly or gradually over time and symptoms may fluctuate.

In this section we look at the most common causes of severe knee pain, how to work out which one you are suffering from and how to treat it. You will also find a guide to help you decide whether you need to see your doctor.

When To See Your Doctor

Some knee symptoms may be a sign that there is something serious going on. See you doctor as soon as possible if you have any of the following:

1) You are unable to take any weight on your leg
2) Your knee is giving way / collapsing when you stand or walk
3) Your knee movement is markedly reduced
4) There is severe knee swelling
5) You are in severe pain
6) There is an obvious deformity of your leg
7) You knee pain is accompanied by redness, swelling and you are feeling unwell/have a fever
8) You notice any changes in bladder/bowel function, vision or sensation in your leg
9) You have had any unexplained weight loss

If you are still unsure what your problem is,visit the knee pain diagnosis section for more help working out what is wrong. And if you are at all worried about your knee symptoms, even if you don't have any of the ones listed above, do get checked out by your doctor. 

  1. Knee Pain Guide
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  3. Symptoms

Page Last Updated: 18/03/19
Next Review Due: 30/10/21

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