Pain behind the knee is a surprisingly common issue affecting athletes, active adults, and even those with sedentary lifestyles. Understanding the root cause of pain behind the knee is crucial for effective treatment and prevention. Whether it’s due to injury, inflammation, or chronic conditions, identifying the origin of back of knee pain can guide the best course of action. Recent research indicates that within a single year, one out of every four adults over the age of 55 will experience ongoing knee pain. In European countries like the UK and the Netherlands, approximately 16% of this population seeks professional medical care to address the discomfort and functional limitations caused by knee issues. In this article, we explore the most common causes, symptoms to watch for, and the most effective treatment options for pain in back of knee.
Common Causes of Pain Behind the Knee
Pain behind the knee can be caused by a variety of issues, ranging from soft tissue strain to more serious joint and vascular concerns. It is essential to recognize the potential causes to ensure appropriate and timely treatment. Whether you’re an athlete or live a less active lifestyle, back of knee pain can interfere with daily activities and athletic performance.
One of the most common questions patients ask is, “Why does the back of my knee hurt?” The answer can vary widely depending on your age, activity level, and medical history. From sports injuries and overuse syndromes to degenerative diseases and vascular conditions, a wide array of potential culprits must be considered when diagnosing this type of discomfort.
Hamstring Injury
Overuse or sudden strain can lead to a hamstring injury, a common cause of pain behind the knee. This often results in bruising, swelling, stiffness, and tenderness, particularly where the hamstring tendons attach near the back of the knee. Biceps femoris tendinopathy, a condition affecting the outer hamstring tendon, is also a known contributor to pain in back of knee in athletes and runners.
Popliteal Cyst (Baker’s Cyst)
A Baker’s cyst forms when fluid builds up in the back of the knee, usually due to underlying joint issues like arthritis or a meniscus tear. This can cause a visible bulge and pain behind the knee. Baker’s cysts may be associated with restricted movement and often occur alongside cartilage degeneration.
Meniscus Tear
The meniscus acts as a shock absorber in the knee joint. When torn, it may cause clicking, locking, and pain in back of knee, especially during movement or weight-bearing. Meniscus tears are among the most frequent knee injuries in athletes, especially those engaging in pivot-heavy sports.
Posterior Cruciate Ligament (PCL) Injury
The PCL stabilizes the knee from the back. Injuries typically occur from a sudden impact, such as a fall or car accident, leading to pain behind knee and swelling. Posterior cruciate ligament injuries often require a detailed clinical history and diagnostic tests to confirm.
Anterior Cruciate Ligament (ACL) Injury
While ACL injuries are commonly associated with front knee pain, referred pain to the back of the knee can also occur. These injuries often result from pivoting or twisting motions. Anterior cruciate ligament (ACL) injury is a serious condition often needing surgical intervention like ACL reconstruction surgery, especially in athletes.
Osteoarthritis
Age-related wear and tear can cause deep knee and posterior pain. Osteoarthritis often leads to stiffness and worsens after activity, contributing to chronic pain behind the knee. Radiographic knee osteoarthritis is common in older adults and may require long-term lifestyle changes and management. Knee osteoarthritis becomes increasingly prevalent with age. Among individuals between 40 and 49 years old, around 10% of women and 7% of men are diagnosed with this degenerative condition. By the time people reach their 60s, the rates jump significantly—impacting 35% of women and nearly 20% of men.
Runner’s Knee (Patellofemoral Pain Syndrome)
Misalignment of the kneecap can create stress and result in pain in the back of knee, particularly during running or prolonged sitting. Patellofemoral pain syndrome often involves overuse syndrome and gait- and postural-alignment-related prognostic factors.
Iliotibial Band Syndrome
A tight IT band can rub against the outer knee structures, leading to referred pain that may include the back of the knee. Balance and stability training can help correct biomechanical issues contributing to this condition.
Bursitis
Inflammation of the small fluid-filled sacs called bursae can lead to localized pain behind the knee. This may be caused by repetitive movement or pressure. Knee bursitis, especially in active individuals, can be managed with rest, ice, and compression.
Inflammatory Arthritis
Autoimmune conditions such as rheumatoid or psoriatic arthritis may affect the knee joint, causing pain behind knee accompanied by stiffness and swelling. Rheumatoid arthritis often leads to swelling management challenges and restricted movement.
Gout and Pseudogout
Crystal deposits in the knee joint from uric acid or calcium can trigger intense inflammation and sudden pain in back of knee. These conditions are often mistaken for infections but require different treatments.
Deep Vein Thrombosis (DVT)
A blood clot in the leg can cause swelling, redness, and pain behind the knee. This is a medical emergency and requires immediate attention. DVT should be considered in any case of unexplained swelling and warmth behind the knee.
Referred Pain from Other Structures
Issues with the hip or lower back may manifest as back of knee pain, especially when nerve irritation is involved. Gait abnormalities and spine-related issues often contribute to this referred pain.
Infection
Joint infections can present with severe pain, warmth, fever, and swelling. Immediate medical intervention is critical. Septic arthritis is a rare but serious cause of pain behind knee and should be part of a thorough outpatient evaluation.
Symptoms to Watch For
Understanding symptoms is vital to early detection and management of pain behind the knee. Some symptoms are mild and improve with conservative care, while others signal the need for urgent medical evaluation. Monitoring the progression of symptoms can help healthcare providers determine appropriate treatment strategies.
- Swelling or redness around the knee: Could indicate inflammation or fluid buildup from bursitis, arthritis, or a Baker’s cyst.
- Sharp or dull pain behind the knee: May be related to hamstring injury, ligament sprain, or cartilage damage.
- Instability or buckling: Often suggests ligament injuries like ACL, PCL, MCL, or LCL damage.
- Clicking or locking sensations: Common in meniscus tears or patellofemoral pain syndrome.
- Warmth and tenderness: May indicate infection or inflammatory arthritis.
- Difficulty bearing weight: Associated with severe injuries like ligament tears or fractures.
- Deformity of the knee or leg, weakness, and numbness or tingling: These symptoms should prompt immediate clinical evaluation.
How Pain Behind the Knee is Diagnosed
Accurate diagnosis is key in addressing the root cause of pain behind knee. A comprehensive approach that includes a physical exam, clinical history, and diagnostic tests can help rule out serious conditions and guide treatment. Diagnostic imaging such as MRI or ultrasound is often used to confirm issues like meniscus tears, ligament injuries, or DVT.
Medical evaluation may also include outpatient evaluation, gait analysis, and evaluation of postural-alignment-related prognostic factors to understand the underlying mechanics contributing to pain.
Home Remedies and Self-Care
Early management of pain behind the knee can be done effectively at home in many cases. Employing the right techniques can reduce swelling and support healing while waiting for a more formal evaluation. Below are some tried-and-true strategies for managing mild to moderate pain in the back of knee.
Rest, Ice, Compression, Elevation (RICE)
Applying the RICE method can significantly reduce inflammation and ease pain in the early stages of injury. Use ice to minimize swelling, a compression bandage or knee braces to stabilize the joint, and elevate your knee to promote fluid drainage. These steps are crucial for acute injuries and are especially helpful for overuse syndrome and ligament injuries.
Avoid HARM Factors
During the acute phase, avoid Heat, Alcohol, Running, and Massage as they can worsen swelling and delay healing. Following the HARM protocol prevents exacerbating conditions such as ACL injuries, meniscus tears, or knee bursitis.
POLICE Protocol
The POLICE protocol (Protect, Optimal Loading, Ice, Compression, Elevation) enhances the RICE method by introducing movement-based recovery. It balances rest with gentle activity, promoting recovery for conditions like patellar tendinopathy and IT band syndrome.
Treatment Options
When conservative care isn’t enough, additional treatments are available to address ongoing back of knee pain. Depending on the diagnosis, interventions can range from medication to surgery. Scottsdale knee pain specialists offer comprehensive care for every stage of recovery.
Medications
Nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce pain and swelling. In some cases, prescribed medications may help with inflammatory conditions or severe arthritis.
Physical Therapy
At Scottsdale Physical Therapy & Performance, we use evidence-based techniques to treat pain behind the knee. Personalized programs focus on strength, flexibility, and correcting movement patterns. This includes at-home exercises, knee strengthening exercises, balance and stability training, and targeted stretches for long-term improvement.
Injections
Cortisone or hyaluronic acid injections may provide relief for inflammatory causes or arthritis-related back of knee pain. These are especially useful in cases where pain limits physical activity or daily function.
Surgery
Surgical options, such as meniscus repair, ACL reconstruction surgery, or knee arthroscopy surgery, may be considered when conservative treatments fail. These are typically reserved for advanced cases involving structural damage or persistent pain.
When to Seek Medical Attention
While some knee pain resolves with rest and home care, others require professional evaluation. Recognizing red flags ensures timely and appropriate care. Always seek help if you’re unsure whether your symptoms could indicate a serious issue.
- Severe or worsening swelling
- Inability to straighten or bend the knee
- Suspected DVT symptoms such as redness and warmth to the touch
- Unrelenting pain behind knee despite rest and at-home care
- Signs of infection like fever, deformity of the knee or leg, or restricted movement
How Scottsdale Physical Therapy & Performance Can Help
Our expert team specializes in diagnosing and treating knee injuries in athletes and active individuals. As Scottsdale knee pain specialists, we provide customized treatment plans designed to restore function and eliminate back of knee pain. We use a combination of physical exam, diagnostic tools, and progressive rehabilitation strategies to address the root cause and improve outcomes.
Whether it’s managing osteoarthritis, rehabilitating from ACL injuries, or reducing inflammation from bursitis, we incorporate evidence-based care tailored to your goals and condition.
Conclusion
Pain behind the knee can stem from a wide range of conditions, from minor overuse injuries to serious vascular concerns. Understanding the cause is the first step to recovery. If you’re experiencing persistent pain in the back of your knee, don’t wait—reach out to Scottsdale Physical Therapy & Performance for expert care.
FAQs
What causes the pain behind the knee?
Pain behind the knee can be caused by hamstring injuries, cysts, ligament tears, arthritis, or even blood clots. Accurate diagnosis is key to effective treatment. Other conditions include biceps femoris tendinopathy, cartilage degeneration, and popliteus muscle strain.
How do you treat back of knee pain?
Treatment varies based on the cause and may include RICE, medications, physical therapy, or surgery. Incorporating lifestyle changes and moderate-intensity aerobic activity can also support long-term recovery.
Can pain behind the knee be a blood clot?
Yes, a blood clot or DVT is a serious condition that can cause pain behind the knee along with swelling, warmth, and redness. Seek medical help immediately if these symptoms occur. Timely medical evaluation and diagnostic tests are critical to avoid complications.
