How do I know if my knee pain is serious? The knee is the most vulnerable joint of the body. This is because the joint is at the highest risk of arthritis, age-related deterioration, and physical injuries. The knee is a ‘hinge’ joint that restricts the joint’s freedom of movement to a single direction, so if you accidentally twist your knee, it will hurt a lot.
As you might be able to guess, the cause of your knee pain can be many things, given how likely it is to get hurt. In some cases, the pain could be an indicator of something serious.
Fortunately for you, most cases of knee pain are the result of overusing the knee or physical injuries. Pain from overuse or physical injuries gets better over time by itself and is rarely something dangerous.
While that’s true, you still need to know whether or not your knee pain is serious. Here is everything you need to know about whether you should be worried or not. Let’s get straight into it!
Knee Pain – Overview
Knee pain can occur due to problems in the muscles, bones, kneecaps, or ligaments. Medically, the conditions causing knee pain are of two types, acute injuries and overuse injuries.
The pain caused by overuse injuries gradually builds up and increases as time goes on. These injuries can be caused by natural deterioration from aging or problems with the bones of the joint.
On the other hand, acute injuries cause pain after a traumatic injury. Acute injuries can be the result of physical injuries but also include muscle and ligament sprains.
The main difference between the two is that acute injuries cause pain immediately after you sustain an injury, while overuse injuries cause pain gradually with no clear indication of the cause of the pain.
Types of Knee Pain
There are several conditions that give rise to knee pain, they are categorized as either overuse injuries or acute injuries. Here are the most common injuries that lead to knee pain.
Patellofemoral Pain Syndrome
Patellofemoral (from the Latin word ‘patella’ meaning kneecap and ‘femur’ the thighbone) pain syndrome is a condition where you feel pain in front of the knee. The pain is usually focused in the region around the kneecap. Patellofemoral pain is the most common type of overuse injury.
Specifically, patellofemoral pain is felt at the front of the knee or deep inside the knee joint around and behind the kneecap. The pain should flare up when you try to perform any movement that puts weight on the knee joint. These movements are climbing or descending stairs, squats, running, and other similar movements. The pain should build up gradually without any clear signs of a sustained injury.
Although it is categorized as an overuse injury, you can develop patellofemoral pain from a previous physical injury that got worse. Patellofemoral pain occurs when the kneecap slides or slips off the femur bone at the joint at a bad angle. This slipping off is similar to dislocation and in turn, causes pain. The most common causes of patellofemoral pain are:
- Rapidly increasing weight or exercise complexity during physical training, and weak muscles supporting the knee
- Weak quadriceps and glute muscles
- Tight hamstrings, quadriceps, hip flexors, etc.
- Limb alignment abnormalities (flat foot, knock knees, rotated hips, etc.)
To treat your patellofemoral pain, the best method is to strengthen your muscles with physical training. Muscle stretches also help prevent pain and can be incorporated into your progressive training regimens. Patellofemoral pain usually does not cause swelling of the knee and it is best to consult a doctor to know if you need braces or tapings for your knee to help with the recovery in case the pain does not improve.
Like a mechanical joint, the knee joint needs to be lubricated to function properly and fluidly. In our bodies, this lubrication is done by the joint fluid that is produced by the surrounding ‘bursa’ sacs in the joint lining. In situations such as excessive pressure on the joint, physical injury, or overuse, the bursa sac can become irritated and develop inflammation.
An interesting tidbit is in medical terms, anything ending with ‘-itis’ means inflammation. So in this case, bursitis is the inflammation of bursa sacs, it is also called the ‘housemaid’s knee’. The following are the causes of bursitis:
- Injury from falls and physical hits is more common among people that take blood-thinning medications
- Infections in the area
- Gout and crystal diseases
- Putting pressure on the joint for a long time (sitting, kneeling, leaning)
- Overuse of joints from repeated action
- Joint stress from physical deformities (having 1 leg shorter than the other)
Bursitis pain is accompanied by swelling but inner knee bursitis swelling might not be visible on the skin. You can use anti-inflammatory drugs to relieve the pain and reduce swelling. Inflammation of all kinds is bad and you should consult a doctor if you notice any swelling.
Patellar Tendinopathy (jumper’s knee)
Patellar tendinopathy (Kneecap tendon disease in non-Latin terms), commonly also called the ‘jumper’s knee’ is a condition where the tendon that connects the shinbone (tibia) to the knee degenerates. In medical terminology, anything ending with ‘-pathy’ means disease.
Tendons are spindle-like tissues that connect a bone with a muscle. A degenerating tendon has tears or disorganized fibres (similar to a worn-out rope). This causes pain when that tendon is activated again for an activity (e.g. running, jumping, squatting). Patellar tendinopathy can affect the tendon at any point between the kneecap and the connecting point on the shinbone.
The patellar tendon is needed by the human body to straighten the knee. Since the jumper’s knee is an overuse type of knee injury, the most common cause of patellar tendinopathy is having weak hamstrings, glutes, and quadriceps. Tightness in these muscles can also have a similar effect. Tendons need to be trained similarly to muscles and joints for physical training.
Overtraining the body frequently with weak tendons can lead to tendon degeneration. Fortunately, an easy way to deal with such a tendon is to do stretching exercises. Long-term treatment for it includes strengthening exercises for the glutes, quadriceps, and hip flexors along with stretching exercises to build more flexibility. Braces and straps can help with pain relief and your doctor can prescribe them for you.
Osteoarthritis in the knee is caused when the shock-absorbing tissue under the kneecap or around the joints degenerates. This degeneration occurs naturally with age, and osteoarthritis is the most common form of arthritis in the world. Osteoarthritis in the knee in most cases only causes morning pain and stiffness that improves as you begin to move, only for it to return if you have been moving too much.
Osteoarthritis does not have a clear tell-tale sign so it is near impossible to self-diagnose. Diagnosis of osteoarthritis is based on multiple factors such as weight, age, fitness level, history, and symptoms. The best treatment for osteoarthritis is usually a lifestyle change. This includes the following 3 things:
Activity change – You should change your daily activities from high-impact movements (running, jumping, etc.) to low-impact movements such as walking, swimming, and biking. This is to avoid putting too much weight on your joints
Weight – People with a higher weight tend to feel osteoarthritis-induced pain more often. Reducing the weight that every joint has to carry for all day-to-day activities improves your life immensely. A 10% reduction in weight can lead to significant improvement among overweight people.
Therapeutic exercise – Regularly doing low-impact aerobic and resistance exercises will gradually increase the shock-absorbing capabilities of your joints. You can also do yoga and Tai Chi to prevent pain episodes and improve your physical health.
Osteoarthritis is a lifelong condition once you develop it, the only way to minimize the effect it has on your life is to actively maintain a lifestyle that strengthens your joints, muscles, and tendons. Osteoarthritis is also an overuse type of knee injury.
The thigh muscles (quadriceps in the front and hamstrings in the back) are responsible for bending and straightening the knee. A muscle strain happens when the muscle over-extends beyond its range of motion and strength. Muscle strains (or ‘pulled muscles’) are nothing serious and only require you to rest for a few days to get better.
It is rare for thigh muscles to strain during routine fitness exercises such as jogging and swimming. Having said that, it is a common occurrence to strain your thigh muscles in sports like soccer, basketball, football, softball, etc. This is because rapid acceleration and deceleration put a lot of strain on your thighs.
You might feel pain when moving your knee with pulled quadriceps and hamstrings. For treatment, you can use ice and compression for quick relief. Over-the-counter painkillers and ibuprofen work just as well but should not be used for more than 7 days. Strains usually improve quickly within days.
If your muscle strain renders you unable to walk, straighten your knees, or develop some swelling near the knee joint, you should consult a doctor for advice. You should also consider going to a doctor if the pain does not seem to improve after two weeks. Muscle strains are the least concerning of all the possible knee-related injuries.
Meniscus tears are a bit special because they can be an overuse injury or a traumatic injury depending on your age and physical health. The meniscus is the shock-absorbing cartilage sandwiched between the thigh bone (femur), and shinbone (tibia). There are two kinds of meniscus tears, traumatic and degenerative.
Traumatic meniscus tears occur when a healthy meniscus is torn by a sudden twisting force. Such tears are common among younger athletes due to their strong and rapid movements. Still, the meniscus does not tear without a decently strong twist so it is unlikely for a non-athletic person to have traumatic meniscus tears.
Degenerative meniscus tears on the other hand, can be considered an overuse injury. In a degenerative meniscus tear, the meniscus becomes soft and weak because of factors such as age and arthritis. Degenerative meniscus tear commonly occurs in people above the age of 40. In most cases, the tear happens when routine physical activity (yard work or sports) tears a meniscus that has become soft and weak because of other factors.
Degenerative meniscus tear pain starts after physical activity and is followed by swelling. Thankfully, a degenerative meniscus tear can be treated without surgery with rest, painkillers, and physical therapy. But if you have a traumatic meniscus tear, you will need arthroscopic surgery to repair the torn meniscus.
Ligament sprain or tear
A ligament is similar to a tendon, but it connects two bones or cartilages instead of muscles (like tendons). Similar to tendons and muscles, the ligaments can sustain damage during physical exertion or when hit at the wrong spot during sports. The knee joint has four ligaments holding it together, they are divided into two pairs.
The inner and outer hinge ligaments (medial and lateral collateral ligaments in medical terms) and the cruciate ligaments between the joints (called the anterior and posterior cruciate ligaments) are all susceptible to injury during sports, brawls, fights, or any other intense physical activity. Injury to these ligaments is mostly a consequence of someone else hitting you near the knee during seemingly simple movements such as landing from a jump or pivoting.
Symptoms of ligament tear include swelling, pain, and feeling like the knee is unable to bear the weight during some movements. While the injury to both ligament pairs can happen from the same event, the treatment for both is different. The torn collateral ligaments heal with rest, physical therapy, rehabilitation, and braces. They rarely require surgery even in extreme cases.
Cruciate ligament tears on the other hand require surgery for people who wish to continue participating in physically demanding activities. Surgery is not recommended for people above the age of 55 and those with light cruciate ligament tears that can improve with physical therapy and rehabilitation.
Fractures and broken bone
Kneecap fractures and broken bones will hurt a lot and will render you unable to move because of the immense pain. While a broken bone may require surgery, a fractured knee just needs rest and plaster to hold it in place.
Lower body fractures take six weeks to recover and in most cases, the recovery is near perfect. Fractures and broken bones require an X-ray scan to be diagnosed properly so you have to consult your doctor for them.
When Should You Go to The Hospital For Knee Pain?
So now that you know all the things that could cause you knee pain, let’s see if your situation is bad enough for a doctor or not. A general rule is if the pain does not prevent you from falling asleep when tired and does not impede your daily activities, then it is not serious enough to visit the hospital. Still, if the pain does not improve even after two days of resting, you should consider going to the doctor.
Swelling On Your Knee
Swelling on the knee can be a sign of some serious problem. Swelling is mostly a consequence of inflammation, and inflammation is always serious. While inflammation is primarily a sign of body healing itself, if it lasts more than two days with no sign of betterment, you must go to the hospital. Other signs of inflammation include swollen area being warm to the touch, having a reddish shade, and you being unable to move the affected area due to pain.
Knee Is Locked and Can’t Be Straightened
Knee locking can happen for several reasons. The inability to move the knee could be due to patellar tendinopathy or muscular strain. Muscular strain is not too bad, while patellar tendinopathy is serious because if left unattended, it will continue to get worse.
If you can’t move the knee despite wanting to, it could be a problem with the nerves which requires immediate medical assistance. The dislocated knee also has similar seriousness. All things considered, a locked knee is almost always a bad sign and requires a prompt visit to the hospital.
Notice a Deformity
Physical deformities such as knock knees are harmless as they do not impede your day-to-day activities. If the deformity disrupts your daily routine, it should be taken seriously. If there is pain alongside the deformity, you should treat it as a medical emergency. Dislocated bones, broken bones, or 3rd-degree ligament tears also cause physical deformities and should be taken seriously.
Knee Is Unstable
An unstable knee is a sign of joint problems such as arthritis, gout, or other overuse injuries. Overuse injuries become worse over time if they are not treated. Therefore, you need to visit a doctor if you have an unstable knee along with pain.
Do remember that if the knee is unstable and does not allow you to put weight on it, it is generally an indication of serious injury.
If the difficulty in walking comes from pain, it may or may not be a problem. Minor inconvenience due to muscular pain is not a big problem. Severe pain that prohibits you from even moving easily is a red flag.
If you are having difficulty walking because of weakness in your knees or limping because of pain in one of your legs, you should go to the hospital for timely treatment.
Can’t Put Weight on Your Knee
Any situation where your knee is unable to hold weight is a serious problem and requires immediate medical assistance. In most cases, you would be unable to put weight on your knee if you have fractures, broken bones, tendon tears, ligament tears, meniscus tears, bursitis, nervous disorder, or dislocated bones. All of these problems require you to go to the hospital.
What Happens If Knee Pain Goes Untreated?
In case of overuse injuries, if the knee is left untreated, it will continue to get worse until it becomes extremely painful. Pain from acute injuries such as muscular strain or ligament sprain heals by itself, granted you get plenty of rest.
Rest is the most important treatment for every knee injury. But if the cause of your knee pain was something serious like a pinched nerve, ignoring it will lead to serious consequences. Not all pain is bad but if you are older than 40 or have recently sustained some injury during some physical activity, not treating the pain can lead to a bad outcome.
How long should knee pain last before seeing a doctor?
If the pain does not improve even after two days of rest, you should see a doctor. Alternatively, if the pain prevents you from resting when you are tired, consult the doctor immediately.
Why does my knee hurt?
Your knee can be hurting for a lot of reasons but the most common cause is osteoarthritis in people older than 40. For others, if you have recently had a strong force hit your knee region, it might have caused some internal damage to the bone, tendons, ligaments, or joints.
What is the best painkiller for knee pain?
Short-acting NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen work best if you are looking for quick and effective pain relief. But you should not use them for prolonged periods to avoid side effects.