A Guide to Physical Therapy for Knee Pain
Knee pain affects approximately 25% of adults, and its prevalence has increased by almost 65% over the past 20 years, accounting for nearly 4 million primary care visits annually.1 Physical therapy can help.
Knee pain can affect people from all walks of life. Young, old, sedentary, and sports professionals all have a chance of dealing with knee pain at some point in their lifetime. Yet, it's important to note that the risk of knee pain and injury increases with age.
Are you experiencing knee pain? If so, you may be considering physical therapy as a treatment option. Physical therapy is a great way to relieve knee pain and improve any mobility impairments with the help of a movement expert. In this article, we will discuss the benefits of physical therapy for knee pain and knee strain. Plus, what to expect from physical therapy.
- Understanding Knee Pain and Knee Strain
- Symptoms of Knee Dysfunction
- What Are the Most Common Causes of Pain?
- How to Diagnose Knee Pain
- What to Expect from Physical Therapy
- Simple Physical Therapy Exercises to Try for Knee Pain
- What If Conservative Care Doesn't Work?
- How to Prevent Knee Pain
- Is It Time to Get Treatment for Your Knee?
Knee pain is a common problem that can be caused by a variety of conditions and issues. Knee strain, a common complaint, is one type of knee pain that is caused by overuse or injury to the tendons and muscles around the knee.
Anatomy of the Knee
The knee is a large weight-bearing joint that is made up of the following bones:
- Femur (thighbone)
- Tibia (shinbone)
- Patella (kneecap)
These bones connect via ligaments, which are strong bands of tissue that provide stability to the knee. These include:
- Anterior cruciate ligament (ACL)
- Posterior cruciate ligament (PCL)
- Medial collateral ligament (MCL)
- Lateral collateral ligament (LCL)
The knee also contains shock-absorbing cartilage. Cartilage is a smooth substance at the end of our bones, allowing them to move fluidly and functionally with each other as a joint. The knee joint also has two special rings of cartilage in each knee for additional shock absorption: the (inner) medial meniscus and (outer) lateral meniscus.
Additionally, the knee joint is surrounded by other connective tissue that creates a joint capsule, muscles, and tendons. Muscle groups include:
- The quadriceps muscle group (located in the front of the thigh)
- The hamstring muscle group (located in the back of the thigh)
- Popliteus muscle (located behind the knee)
- Gastrocnemius and soleus muscle group (located in the calf)
These muscle groups work together to move the knee joint. The quadriceps muscles straighten the knee at a basic level, while the hamstrings bend the knee. Plus, other surrounding muscles play a role in knee stability and function, including the:
- Iliotibial band (ITB), located on your outer knee up to your outer thigh (and pelvic bones), connected to the tensor fasciae latae (TFL) muscle (a hip flexor)
- Hip adductors (inner thigh), including the pectineus, adductor magnus, longus and brevis
There are various signs and symptoms associated with knee joint problems. The most common symptom is local muscle or joint pain, ranging from a dull ache to sharp pain. Additionally, it can occur suddenly (acutely) or have a gradual onset (chronic). Other symptoms may include:
- Tenderness to touch
- Locking or catching sensation
- Popping or grinding noise when moving the knee
- Instability or giving way
- Reduced range of motion
- Difficulty walking or bearing weight through the leg
- Weak muscles
- Inability to complete daily activities when knee pain occurs
Types of Knee Pain
The location and quality of knee pain can give clues as to what the underlying cause might be. You can also consider what's going on in your hips to help identify related causes of knee joint pain, such as hip weakness or stiffness. Let's review.
- Pain in the front of the knee (anterior): Typically caused by issues with the kneecap (patella), referred to as patellofemoral pain. It often is worse with flexion-biased (bending) movements such as squats and stairs and is most common in female athletes and runners. It was once thought that poor tracking was the cause of kneecap pain. However, evidence illustrates that there are a lot of potential factors to consider, such as the knee's ability to handle the load and even lifestyle factors like sleep.2
- Pain in the side of the knee (lateral): Typically caused by issues with the iliotibial band that connects to the outside of the knee. It is often worse with activities like stairs and running, most common in runners and other endurance athletes. Pain is usually attributed to movement patterns of the lower body that increase strain on the outer knee and lead to inflammation and pain.
- Pain on the inside of the knee (medial): Pain in the inner knee can be caused by irritation of the medial collateral ligament (MCL) or meniscus, either from overuse in poor alignment (imagine a knock-knee position) or a sideways blow to the knee.
- Pain in the back of the knee (posterior): Pain in the back of the knee is often indicative of issues with the hamstrings or tendons. Hamstring tendonitis (inflammation of the tendon) is a common injury in runners and other athletes who sprint or do explosive movements that load the back of the knee. Swelling behind the knee, known as a Baker's cyst, is also common behind the knee and can cause discomfort.
There are many reasons you might experience knee pain. While there are dozens of possibilities, here are some of the most common:
The most common cause of knee pain in adults over the age of 50. Arthritis can be degenerative (wearing away) or inflammatory (swelling). The two most common types are knee osteoarthritis and rheumatoid arthritis.
Bursitis is inflammation of a small, fluid-filled sac (bursa) that sits between tendons, muscles, or bones. For example, the shoulder, hip, and knee have several bursae surrounding them. Bursitis often occurs due to overuse or repetitive motion and is seen in athletes who do a lot of jumping (like basketball players) or squatting (like weightlifters). Bursitis can also develop from kneeling or a direct impact to the front of the knee, resulting in prepatellar bursitis (above the kneecap).
This is the inflammation of a tendon, the tough tissue that connects muscle to bone. The knee has four primary tendons that can all be affected: the patellar tendon (connects the kneecap to the shinbone), quadriceps tendon (connects the thigh muscles to the kneecap), and two hamstring tendons (connects the hamstring muscles to the back of the shinbone). Inflammation is primarily caused by repetitive motion.
This chronic (long-term) condition results in the breakdown of collagen in a tendon, leaving it scarred and fibrous — leading to painful knee dysfunction. While tendonitis may be a precursor, it can also happen independently with chronic overuse.[^tendonitis-tendinosis]
The meniscus is a C-shaped piece of cartilage that sits between the thighbone and shin bone and acts as a shock absorber. A meniscus tear is a common knee injury, especially in athletes. A sudden twisting motion or gradual small tears can cause it. Symptoms include pain, swelling, and stiffness.
The anterior cruciate ligament (ACL) is a major ligament in the knee that connects the thighbone to the shinbone. It stabilizes the knee and helps it function smoothly. An ACL tear is a common knee injury, especially in athletes. It can be caused by a blow to the knee, sudden twisting motion, or landing awkwardly from a jump. Symptoms include pain, swelling, and instability. Other ligaments or the menisci can easily be involved at the same time with this type of injury as well.
Knee pain can also be caused by a direct knee blow or a fall injuring the knee. This type of injury can result in a bruise, ligamentous sprain/tear (ACL, PCL, LCL, MCL), or fracture to the thighbone, shinbone, or kneecap. Outside of a direct impact, overuse can also lead to a stress fracture of the lower leg bones around the knee.
The patella (kneecap) is a small bone that sits in front of the knee joint. It helps stabilize the knee and allows for smooth leg movement. A patellar dislocation occurs when the kneecap pops out of place, usually to the outside of the knee. It can be caused by a direct blow to the kneecap, a fall onto the knee, and other mechanical challenges related to deep flexion and twisting. Some people are at higher risk of dislocation due to having a connective tissue disorder (such as Ehlers-Danlos) or congenital issues that affect kneecap alignment.
Iliotibial Band Syndrome (ITBS)
The iliotibial band is a long strip of tissue that runs from the hip to the shinbone outside the leg. It helps to stabilize the knee joint. Iliotibial Band Syndrome (ITBS) is a common overuse injury in runners and other athletes. It is caused by repetitive motion, such as running or cycling, that irritates the iliotibial band, where it rubs against the thigh bone at the outer knee. Hip weakness is often a contributing cause of ITBS.
Less Common Causes
- Baker's cyst: This type of fluid-filled cyst forms behind the knee. It typically begins with a knee injury (chronic or acute) or knee arthritis that causes the knee to produce too much lubricating fluid.
- Gout: This is a type of arthritis that occurs when there is too much uric acid in the blood. Uric acid is a waste product that is normally excreted in the urine. When there is too much, it can form crystals that deposit in joints, causing inflammation and pain. Gout often affects the big toe but can also affect the knee.
- Osgood-Schlatter disease: This condition affects the growth plate (the area of new bone growth) in the knee, resulting in a painful lump under the kneecap. It is seen in active children and adolescents going through a growth spurt.
- Infection: Osteomyelitis and septic arthritis are rare infections of the bone or joint that can cause knee pain, swelling, fever, and chills. It is most often seen in children (under 5) and young adults.
- Chronic conditions: Knee pain can also be caused by other health conditions, such as diabetes, obesity, and gout. If you have knee pain that does not go away with home treatment, you should see your doctor or physical therapist to get some answers.
If you are experiencing knee pain, you will typically see your primary care physician, an orthopedic doctor (surgeon), or a physical therapist. To get the best conservative care with less dependence on pain medications, injections, or even surgery, it's best to see a physical therapist first for a proper diagnosis and long-term sustainable results.3
Want to get knee pain relief as soon as possible? Remember, you can go straight to a physical therapist without a referral to get the relief you're looking for sooner rather than later.
A Physical Therapy Evaluation
When you see a physical therapist, they will conduct a thorough subjective and objective examination to determine the cause of your knee pain. This will help to rule out any serious causes for your pain (in case they need to refer you out) and identify any potential risk factors that may have contributed to your condition.
The subjective examination includes taking a detailed past medical history of your current condition, as well as any previous injuries or surgeries you've had. Plus, they'll try to gain an understanding of your lifestyle and why you need to get rid of your knee pain. They will ask questions like:
- When did your knee pain start?
- What activities or positions make your knee pain worse?
- Does anything relieve your knee pain?
- Do you have other symptoms, such as swelling, locking, or giving way?
- Have you had any previous injuries or surgeries to your knees?
- Have you undergone any major lifestyle changes recently?
The objective examination includes tests and measures specific to your knee pain complaint that help the physical therapist determine what is causing your pain and how best to treat it. These include:
- Visual inspection
- Range of motion
- Strength testing
- Joint mobility testing
- Functional testing
- Special tests to evaluate joint and tissue integrity
This will help your physical therapist determine a proper diagnosis and treatment plan specific to your needs.
Imaging and Diagnostics
Sometimes, your physical therapist or PCP may refer you for additional imaging studies, such as an X-ray, MRI, or CT scan. These can be helpful in ruling out any serious causes of knee pain, such as osteomyelitis or fracture. Plus, determine the extent of the damage. However, it's important to note that tissue damage, such as a ligament tear, is much less important than the current function and stability of the knee.4
Other diagnostic tests can be ordered as needed, such as a blood test or urine test to look at systemic causes of pain like gout and RA.
Evidence-based practice illustrates that the best way to address knee pain is to focus on exercise prescription, weight management, and psychosocial factors.3 Let's review some more specific treatments you will actively encounter during your physical therapy sessions.
Education: A physical therapist will provide you with extensive information about your knee pain condition and what you can do to help manage it. This includes things like:
- The importance of maintaining a healthy weight
- Understanding the true cause of your pain and how to manage it effectively long term
- How to promote optimal tissue health, healing, and balance
- Proper use of assistive devices (if needed)
Manual therapy: A physical therapist may use manual therapy techniques (hands-on treatment), such as joint mobilizations and soft tissue massage, to help decrease your knee pain.
Modalities: In some cases, your physical therapist may use modalities like ultrasound, electrical stimulation, heat, or ice to help control your pain in the short term. While this should never be the focus of your treatment, due to its passive nature, it can help you tolerate other aspects of your home exercise program better initially if it's an issue
Ergonomics/posture/mechanics: The way we sleep, stand, get up and down, drive, cook, dance, etc., all load our joints, including the knees. If this load is too much or out of balance, it can lead to pain and injury. Your physical therapist can help you decipher these issues and help you problem-solve and adjust these to optimize your knee alignment and tissue health.
Lifestyle: Physical therapists can help you understand how your current activity levels and choices impact your knee pain. They will work with you to develop an appropriate treatment that meets your needs and lifestyle. Plus, they can help introduce other healthy lifestyle changes like smoking cessation, proper hydration, or sleep hygiene if these are issues.
Exercise prescription: Physical therapists are movement experts and will prescribe specific exercises to help you regain knee joint range of motion, improve muscle strength and endurance, and improve your overall flexibility and agility. These may be done in the clinic, as homework, or both. The ultimate goal is for these to carry over and help you make meaningful changes in your daily activities to boost knee function and reduce pain.
If you're experiencing knee pain, there are a few things you can do at home to help manage your symptoms. While it's always best to seek professional care like physical therapy, especially if the pain is severe or persists for more than a few days, these simple physical therapy exercises may provide some relief. However, there's always a risk with trying exercises on your own (read more about the dangers of DIY physical therapy).
Here's a quick overview of a few strengthening exercises you can try if they are pain-free. If you feel pain, modify it to a smaller range or stop it immediately until you get professional guidance from a physical therapist. (Not all pain is bad, you will know once you talk to your physical therapist.)
This is an easy starting exercise to promote full knee range of motion. This exercise is preferred over traditional straight leg raises, which can be painful and isn't very functional.
- Start by lying on your back with the legs straight
- Bend the affected knee while sliding the heel up closer to your buttocks
- Bend as far as you can comfortably and hold for 3 to 5 seconds
- Return to the starting position (with a straight leg) and repeat for 10 to 15 repetitions
- Repeat on the other leg as needed for 2 to 3 sets total
- If needed, place something under your heel that makes it easier to slide, such as a plastic bag (if you're on carpet) or a towel (if you're on hardwood)
Bridges are a great way to target the hamstrings and glutes (hip muscles) while promoting full knee range of motion.
- Start by lying on your back with feet flat on the ground and knees bent to about 90 degrees
- Tighten the muscles in your buttocks and raise your hips off the ground until your thighs and torso are in line with each other
- Hold for two to three seconds and slowly lower back to the starting position
- Repeat for up to 15 repetitions for 2 to 3 sets total
- As you get stronger, hold a weight in your hands or place a weight on your pelvis for added resistance
- If you are experiencing any hamstring cramping, do a quick hamstring stretch, then modify how high you lift and make sure you are focusing on activation of the glute muscles
Standing Hip Extension
This is a great way to target the leg muscles in the back of your thigh and improve hip mobility (a common contributing factor to knee dysfunction).
- Start by standing with feet shoulder-width apart and hands on hips
- Keeping a straight leg, kick one leg backward as far as you comfortably can without arching the back or leaning forward
- Repeat for up to 15 repetitions on each leg for 2 to 3 sets total
Sit to Stand from a Chair
This is a functional movement that we do every day, but it can be difficult for those with knee pain.
- Start by sitting in a chair with feet shoulder-width apart and flat on the ground
- Using your arms for balance, focus on standing up straight by shifting your weight into your feet and forward before pushing "up" with your legs
- Focus on keeping your weight evenly distributed between your two feet as you move up and down
- Slowly return to a sitting position without plopping into your seat
- Repeat for 10 repetitions for 2 to 3 sets total
This is a great exercise to improve balance and proprioception of the entire leg and trunk (knowing where your body is in space).
- Start in a standing position on one leg with a slight bend, then lift the other foot off the ground to balance
- Stand near a table, wall, or counter if needed for safety
- Keeping your pelvis level, focus on keeping your balance without the use of your hands for 30 or more seconds
- Repeat 2 to 3 times on each leg
- To progress, stand on a bent knee, or soft surface, move your upper body, turn your head, or distract yourself with an activity like throwing a ball
In some cases, physical therapy and other conservative care options may not be enough to provide the relief you need. If this is the case, your physical therapist will likely refer you to another provider for further evaluation. Depending on your individual needs and diagnosis, this might include an orthopedic surgeon, pain management doctor, or rheumatologist.
If you do end up needing more aggressive treatment, don't worry! Highly trained physical therapists are still an integral part of your care team and will continue to work with you through your entire journey, from start to finish.
Did you know that physical therapy treatment before knee surgery, such as a knee replacement, can improve your post-surgical outcomes? Improved strength, endurance, weight management, and optimism about surgery play a role in this.5
The best way to avoid or reduce knee pain is to prevent it from occurring in the first place. Of course, not all knee pain can be avoided. But following these general guidelines will help reduce your risk and help you manage any knee pain.
- Stay active, strong, and maintain a healthy weight: Exercise promotes optimal tissue health, thanks to circulatory and extensibility benefits. Try stretching and strengthening exercises that target the upper body, thighs, core, and hip muscles.
- Wear supportive shoes: Proper footwear can help to distribute your weight evenly and reduce stress on your knees. Perhaps more importantly, avoid wearing old shoes with uneven wear or impractical shoes for aesthetics that propagate poor lower body alignment.
- Avoid high-impact activities: If you have joint problems or are overweight, avoid activities that place extra stress on your knees.
- Approach high-impact activities with good form: Not all impactful movement needs to be avoided. In fact, there are a lot of benefits to these- such as bone health. To reduce knee impact, move with grace and good form (a physical therapist can help you with this).
- Warm-up before you exercise: A proper warm-up helps increase blood flow and flexibility, reducing your risk of injury.
- Cool down after exercising: Cooling down helps your body to recover from the rigors of exercise and prevents stiffness and soreness.
- Reduce your body's inflammatory markers: Many daily choices can put your body in a state of inflammation that you can control. This might include nutritional changes, stress reduction techniques, improved hydration, better sleep habits, and specific exercises.
If you have any questions or concerns, talk to your CityPT physical therapist. A session — whether virtually or in a physical therapy clinic — can help create a customized prevention plan or knee conditioning program that's right for you.
If you're experiencing knee pain, it's important to get it checked out by a CityPT physical therapist. Physical therapists can help you identify the root cause of your pain and provide the treatment you need to get back to your regular activities with confidence.
Don't let knee pain hold you back from living your best life. Schedule an appointment with a CityPT physical therapist today to start your recovery journey.
This guide is intended for informational purposes only. We are not providing legal or medical advice and this guide does not create a provider-patient relationship. Do not rely upon this guide (or any guide) for medical information. Always seek the help of a qualified medical professional who has assessed you and understands your condition.
Jean-Francois Esculier, PhD, PT; Kevin Maggs, BSc, DC; Ellora Maggs, PT, DPT; Blaise Dubois, BSc, PT. A Contemporary Approach to Patellofemoral Pain in Runners. J Athl Train (2020) 55 (12): 1206–1214. https://doi.org/10.4085/1062-6050-0535.19 ↩
Jones, Brandon; et al. Nonsurgical Management of Knee Pain in Adults. Am Fam Physician. 2015 Nov 15;92(10):875-883.[https://www.aafp.org/afp/2015/1115/p875.html}(https://www.aafp.org/afp/2015/1115/p875.html) ↩ ↩2
Chung HW, Ahn JH, Ahn JM, Yoon YC, Hong HP, Yoo SY, Kim S. Anterior Cruciate Ligament Tear: Reliability of MR Imaging to Predict Stability after Conservative Treatment. Korean J Radiol. 2007 May-Jun;8(3):236-241. https://doi.org/10.3348/kjr.2007.8.3.236 ↩