A Guide to Physical Therapy for Knee Pain and Knee Strain
Knee pain affects approximately 25% of adults, and its prevalence has increased almost 65% over the past 20 years, accounting for nearly 4 million primary care visits annually.1
Knee pain can affect people from all walks of life. The 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 Exercises to Try for Knee Pain
- What If Conservative Care Doesn’t Work?
- How to Prevent Knee Pain and Strain
- 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 are connected by 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 and allows them to move fluidly and functionally with each other as a joint. The knee 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. At a basic level, the quadriceps muscles straighten the knee, while the hamstring muscles 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, 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 problems. The most common symptom is pain, which can vary 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 bearing weight through the leg
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 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 used to be 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 hamstring muscles 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:
This is 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 osteoarthritis and rheumatoid arthritis.
This is the inflammation of a small, fluid-filled sac (bursa) that sits between tendons, muscles, or bones. The knee has several bursae surrounding it. Bursitis often occurs as a result of 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 is a chronic (long-term) condition that results in the breakdown of collagen in a tendon, leaving it scarred and fibrous. This can lead to painful knee dysfunction. While tendonitis may be a precursor, it can also happen independently as well with chronic overuse.7
The meniscus is a C-shaped piece of cartilage that sits between the thighbone and shinbone and acts as a shock absorber. A meniscus tear is a common knee injury, especially in athletes. It can be caused by a sudden twisting motion or gradual small tears. 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 blow to the knee or a fall that injures 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.
The patella (kneecap) is a small bone that sits in front of the knee joint. It helps to stabilize the knee and allows for smooth movement of the leg. 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 on the outside of the leg. It helps to stabilize the knee joint. 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 is a type of fluid-filled cyst that 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 is a condition that 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 who are going through a growth spurt.
- Infection: Osteomyelitis and septic arthritis are both 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 long-term sustainable results.3
Want to get knee pain relief as soon as possible? Remember, you can go straight to 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 PT care provider, 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), as well as identify any potential risk factors that may have contributed to your condition.
The subjective examination includes taking a detailed 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 any 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, as well as 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
All of this will help determine a diagnosis and treatment plan specific to your needs.
Imaging and Diagnostics
In some cases, 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 to rule 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.5
Additionally, 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 with a focus on exercise prescription, weight management, and addressing psychosocial factors.3 Let's review some of the more specific treatments you will actively encounter during your sessions.
Education: A physical therapist will provide you with extensive information about your knee pain condition, as well as 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
Manual therapy: A PT care provider may use manual therapy techniques, 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 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 place a load on our joints, including the knees. If this load is too much or out of balance it can lead to pain and/or 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 are impacting 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, as well as 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, especially if the pain is severe or persists for more than a few days, these simple exercises may provide some relief in the meantime. However, there's always a risk with trying exercises on your own (read more about the dangers of DIY PT).
Here's a quick overview of a few exercises you can try if they are pain-free. If something hurts, modify it to a smaller range or stop it immediately until you get professional guidance. (Not all pain is bad, but you won't know until you talk to your physical therapist.)
This is an easy starting exercise to promote full knee range of motion.
- Start by lying on your back with the legs outstretched
- 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 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, while also 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, modify how high you lift and make sure you are focusing on glut activation
Standing Hip Extension
This is a great way to target the 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 your knee straight, 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 flat on the ground and shoulder-width apart
- 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 (the ability to know where your body is in space).
- Start by standing on one leg with the other leg slightly bent at the knee
- 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 soft surface, move your arms, 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. This might include an orthopedic surgeon, pain management doctor, or rheumatologist, depending on your individual needs and diagnosis.
If you do end up needing more aggressive treatment, don't worry! 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 before knee surgery, such as a knee replacement, can improve your post-surgical outcomes? Improved strength, endurance, weight management, and feeling optimistic about surgery all play a role in this.6
The best way to avoid 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 to reduce your risk and help you manage any pain that does occur.
- Stay active, strong, and maintain a healthy weight: Exercise promotes optimal tissue health, thanks to circulatory and extensibility benefits.
- 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 too much 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 to increase blood flow and flexibility, which can reduce 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: There are a lot of daily choices that 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, be sure to talk to your physical therapist. They can help you create a customized prevention plan that's right for you.
If you're experiencing knee pain, it's important to get it checked out by a professional. Physical therapists can help you identify the root cause of your pain and provide you with 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 get started on your road to recovery.
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.
- Bunt, Christopher. Knee Pain in Adults and Adolescents: The Initial Evaluation. Am Fam Physician. 2018 Nov 1;98(9):576-585. https://www.aafp.org/afp/2018/1101/p576.html↩
- 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)↩
- 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↩
- D. Z. H. Levett,C. Grimmett. Psychological factors, prehabilitation, and surgical outcomes: evidence and future directions. First published: 02 January 2019, https://doi.org/10.1111/anae.14507↩