What Causes Pain Behind the Knee?

Pain behind the knee, also known as posterior knee pain, can result from various conditions affecting the muscles, tendons, ligaments, or joints in the area. It may be caused by overuse, injury, or underlying medical conditions such as arthritis, bursitis, or a Baker’s cyst.

In some cases, nerve compression or vascular issues can also contribute to pain. Identifying the root cause is essential for effective treatment and preventing further complications. Because the knee is a complex joint that is subjected to significant impact from even routine daily activities, people can often prevent or lessen knee damage by avoiding impact and strain on the joint.

What are the Causes?

Working closely with a physician is crucial when diagnosing back of the knee pain because certain causes take time to fully heal.

Leg cramps:

When muscles get overly tight, cramps happen. The reason for this tightness could be because the muscle is overworking itself without being stretched.

Different parts of the knee may be impacted by overuse syndrome. A person with this condition may also experience cramping in the calf or thigh close to the knee. It feels like an abrupt, severe muscle spasm.

Other potential causes of leg cramps include:

• Dehydration
• infections, such as tetanus
• liver disease
• excess toxins in the blood
• nerve problems

Leg cramps are another common side effect of pregnancy for expectant mothers.

Stretching their calves on a daily basis may help some persons who frequently have leg cramps. In order to lessen the tension on the knee and surrounding muscles, individuals can also attempt decreasing their stride.

Arthritis:

Your treatment plan may include:

• natural remedies
• exercise
• steroid injections
• medications.

Chondromalacia:

When the cartilage inside a joint degrades, chondromalacia results. The patella, the area beneath the kneecap, is the most frequently affected by cartilage degradation.

Chondromalacia can be caused by knee injuries, aging, arthritis, or excessive use.

After sitting for a long time or climbing stairs, the pain could worsen. Other signs and symptoms could be:

• weakness or buckling of the knee
• Treatment may include ice, pain relieving medicine (NSAIDs), and physical therapy.

Baker’s cyst:

Since small cysts usually don’t hurt, Baker’s cysts might not be apparent at first. But as the cyst enlarges, it could cause pain by moving the nearby muscles or applying pressure to the tendons and nerves.

A Baker’s cyst could get as big as a table tennis ball. Baker’s cyst patients frequently experience pressure in the rear of their knee, which, if the cyst is touching a nerve, may result in a tingling sensation.

Although treatment can alleviate the symptoms, Baker’s cysts are generally not a reason for alarm.

Gastrocnemius tendonitis:

Your lower leg’s back, or calf, is made up of the gastrocnemius and soleus muscles. These muscles assist you in pointing your toes and bending your knee.

The gastrocnemius muscle may be strained or torn by sports like tennis and squash that demand you to jump from a standing position to a running one very quickly. When this muscle suddenly hurts in the back of your leg, you know you’ve strained it.

Other symptoms of a calf strain include:

• pain and swelling in the calf
• bruising and tenderness in the calf
• trouble standing on tiptoe.

The degree of the strain will determine how the calf is treated. For a moderate sprain, for instance, your treatment regimen can involve rest, physical therapy, and over-the-counter (OTC) painkillers.

An Achilles tendon rupture, on the other hand, can take up to six months to heal and may necessitate surgery.

Osteoarthritis:

Osteoarthritis in the knee can cause other symptoms, such as loss of motion or difficulty bending the knee. Inflammation can make the joint uncomfortable and rigid. This pain may also be experienced in various areas surrounding the knee.

It is possible that autoimmune diseases like rheumatoid arthritis and lupus are contributing to the pain.

Runner’s knee:

This usually results in an uncomfortable, dull pain behind the knee.

Additional signs of runner’s knee include:

• Random weakness in the leg and knee,
• buckling or giving out of the knee,
• restricted movement in the leg and knee,
• crackling or grinding sensation as the knee bends.

Hamstring injury:

A hamstring injury occurs when one or more of the muscles in the rear of the thigh are torn or strained. Among these muscles are:

• The semitendinosus and biceps femoris
• The semimembranosus
• Excessive pulling of the hamstring muscle results in a strain.
• If it is tugged too much, it may tear completely, and it may take months for it to mend properly.

Meniscus tears:

Each side of the knee has a piece of cartilage called the meniscus. This cartilage may rip if you twist your leg when bending it or crouching. When a meniscus tear occurs, many individuals hear a pop.

Although it might not be felt right away, meniscus tear pain usually gets worse over the course of the following few days.

Meniscus tears often cause other symptoms, including:

• loss of knee motion
• weakness and fatigue in the knee and leg
• swelling around the knee
• Knee locking up when used

Jumper’s knee:

Patellar tendonitis is referred to as “jumper’s knee.” The patellar tendon, which joins your kneecap (patella) to your shinbone, is injured in this disorder.

Overuse or overloading of the patellar tendon results in jumper’s knee. For instance, the tendon may sustain microscopic tears as a result of repetitive motions like jumping or changing direction. The tendon eventually weakens and swells up.

Jumper’s knee causes pain in the kneecap. The pain gets worse over time. Other symptoms may include:

• weakness
• Knee stiffness
• trouble bending and straightening your knee.

Dislocations and Fractures:

One of the bones that connect the thigh, shin, and kneecap may have been damaged or misaligned if your knee hurts a lot after a bump, bang, or tumble.

Immediately visit a doctor or the emergency department. Tiny fissures at the extremities of the leg bones can occasionally result from slower fractures. This may occur if you have begun to use your knee more.

Iliotibial Band Syndrome:

A ligament that runs along the outside of your thigh is called the “IT band,” and it can get inflamed and swollen when it rubs against the bone.

This is more likely to occur when you exercise by running or riding a bike. Sitting for a time or going downhill may make it pain worse. After warming up, you might feel better, but if you don’t rest the injury and allow it to heal, it might worsen.

Bursitis:

This is typically the result of overworking your knee, which makes it swollen, stiff, and warm or uncomfortable to the touch. The condition is also referred to as “clergyman’s knee” or “housemaid’s knee” since those who work in these occupations frequently kneel. It occurs when the bursa, which are tiny, fluid-filled sacs that cushion your knee joint, become inflamed and bloated. Even when you’re sleeping, you might still feel pain.

Gout and Pseudogout:

The symptoms of both are similar: the swelling and pain are frequently severe and come on quickly. Your knee might feel hot, inflamed, and rigid. When crystals collect in the joint, it occurs. Uric acid accumulation causes gout, which frequently affects the big toe.

Infection:

Septic arthritis may result from a direct damage to the joint or from another infection. Along with the rapid onset of the pain, you’ll also feel nauseated, irritable, and feverish. To determine which bacteria is causing it and how to treat it, your doctor could use a needle to extract some fluid from your knee. Viruses and parasites can also infect your joints, though this is less common.

Referred Pain:

For instance, knee pain may be caused by issues in your foot, hip, or back. Your brain may become confused about the source of pain signals, or nerves may transfer pain from one place to another. Although the sensation is genuine, your knee might not be the issue.

Anterior cruciate ligament injuries:

ACL strains are frequently caused by abrupt pauses or direction changes. ACL strains can produce a popping sound, followed by pain and swelling, much like meniscus tears.

A common and dangerous injury that can keep an athlete out of action for a long time is an ACL tear. Reconstructive surgery is typically necessary for torn ACLs.

Posterior cruciate ligament injuries:

Although it is less prone to sustain an injury than the ACL, the posterior cruciate ligament (PCL) serves a comparable function.

Traumatic situations like being in a car accident or falling straight onto the knee from a height can cause PCL injuries. The ligament may totally rip if sufficient power is applied.

PCL injuries result in symptoms like:

• knee pain
• stiffness in the knee if bending
• difficulty walking
• swelling in the knee

A PCL injury may heal more quickly if the knee is completely rested. Surgery might be necessary for a significant PCL damage, though.

Deep vein thrombosis:

A thrombosis is a blood clot. Standing up causes extra agony for many DVT sufferers.

Additional signs of DVT could include:

• Warm or red skin to the touch,
• swelling in the affected area,
• exhaustion in the leg, and clearly visible surface veins
• smoking, being older, and being overweight are risk factors for DVT.
• Sedentary lifestyles may also increase the risk of developing DVT.

Because DVT can worsen if the clot breaks free into the bloodstream, it requires medicine and care.

Symptoms of Pain Behind the Knee:

A Baker’s cyst causes swelling and sometimes pain at the back of your knee, which you’ll probably notice. It may start to look red too.You might feel warmth radiating down your calf and hear a pop if your cyst explodes. It might also begin to appear red.

The back of your knee may hurt if you have a meniscus tear, especially if you bend or twist it. If you tear your meniscus, you might experience a “pop.” You might have some swelling, usually a few hours following your meniscus tear. It could also feel like your knee is locking or catching.

When you put weight on your knee, osteoarthritis typically hurts, but it normally goes away when you relax. You might not be able to move your knee as easily in the morning or after sitting for a long time because it may be stiff. Once you start moving around, this usually gets easier. Additionally, there can be some swelling over your knee.

You’ve most likely hurt other areas of your knee in addition to your posterior cruciate ligament (PCL) injury. However, you might just have little soreness or even none at all if you’ve simply hurt your PCL. You might experience pain behind your knee, particularly when kneeling, if your injury is more serious. Additionally, descending an inclination could be painful. For instance, you can experience soreness behind your knee when descending stairs, walking, or jogging downhill.

Seeing a doctor is crucial if you have a sore, swelling calf. This is because a clot in your leg (deep vein thrombosis) may also be the source of this swelling, in which case you will want immediate medical attention.

Diagnosis of pain behind the knee:

If they suspect you have a posterior cruciate ligament injury, they may refer you to have an X-ray or a magnetic resonance imaging (MRI) scan.

Treatment

Stretching the muscles surrounding the knee, particularly the quadriceps, calves, and hamstrings, is always a good idea. This might improve the muscles’ response to action, but it might not guard against some of the traumatic causes of knee pain.

When an injury initially occurs, doctors frequently advise the RICE treatment to help reduce pain and swelling. RICE is an acronym for:

• Resting (the leg)
• Icing (the knee)
• Compressing (the area with an elastic bandage)
• Elevating (the injured leg)

People should speak with a doctor or physical therapist about the best course of action for them. Another way to reduce pain and swelling while the knee heals is to take nonsteroidal anti-inflammatory drugs (NSAIDs), some of which can be purchased online, like ibuprofen.

For more severe injuries, doctors could use a CT or MRI scan to get a full picture of the affected area. Depending on the severity, they may subsequently recommend physical therapy or surgery as remedies.

FAQs

References

• Knee pain. (n.d.). Mount Sinai Health System. https://www.mountsinai.org/health-library/symptoms/knee-pain
• Why knees hurt. (n.d.). WebMD. https://www.webmd.com/pain-management/knee-pain/ss/slideshow-why-knees-hurt
• Johnson, J. (2023, May 19). What causes pain behind the knee? https://www.medicalnewstoday.com/articles/321128
• Watson, S. (2024, January 30). What’s causing this pain in the back of my knee? Healthline. https://www.healthline.com/health/pain-in-back-of-knee