What is Patellofemoral Pain Syndrome?

Patellofemoral Pain Syndrome (PFPS), often called runner’s knee, is one of the most common causes of knee pain, especially among athletes. This condition accounts for up to 25% of knee injuries treated in sports medicine clinics.¹
The pain usually occurs at the front, behind, or around the kneecap (patella), and it’s common in runners and those who engage in sports involving a lot of running and jumping. While most people find relief with conservative treatments, the discomfort can persist for years in some cases.²
If left untreated, patellofemoral pain can limit your activities and potentially lead to chronic joint problems. So, addressing symptoms early is crucial for maintaining an active lifestyle.

Overview of the Knee Joint

The knee joint is one of the most complex joints in the body, crucial for supporting body weight and allowing a wide range of activities such as walking, running, and jumping. It consists of several bones and tissues that provide stability, flexibility, and movement. Here is an overview of the knee joint’s structure:

Bones

Femur: The thigh bone, forming the upper part of the knee joint.
Tibia: The shin bone, forming the lower part of the knee joint.
Patella: The kneecap, a small, triangular bone that protects and supports joint movement.

Cartilage

Articular Cartilage: Cushions the ends of the femur, tibia, and patella, ensuring smooth movement of the knee joint.

Ligaments

Ligaments: Provide stability by connecting bones within the joint.

Tendons

Tendons: Connect muscles to bones, enabling movement.

Image showing anatomy of knee joint — Image showing the anatomy of the knee joint

Causes of the PFPS

Multiple factors cause patellofemoral pain syndrome. They may include;

Overuse/Repetitive Movement:

It is the most common cause of pain. Repetitive movements like running and jumping increase the workload on the kneecap, causing irritation under it.

Muscular Imbalance:

If the muscles around your hip and knee, especially the quadriceps, are weak or tight, they may cause PFPS. If the quadriceps are weak, they are unable to support your knee during the movement. Similarly, if they are tight, they may put increased tension on your knee.

Enhanced Training Level:

If you suddenly start any new activity or increase the intensity of your training, you may develop PFPS.

Malalignment of Patella:

If your knee has a structure different from normal biomechanics by birth, you may feel pain from PFPS.

Patellar Trauma:

Direct or indirect injury to the patella or kneecap can damage the patella and cause PFPS.

Symptoms of PFPS

The pain from patellofemoral pain syndrome is usually dull and achy, but sometimes, you may feel a sharp pain in or around your patella. You may also experience:³

Worsening pain while squatting, stair climbing, running, or prolonged sitting
You may feel like your kneecap is moving while walking
Pain can limit your ability to work, play sports, or engage in physical activities

Risk factors of PFPS

The risk factors for developing patellofemoral pain syndrome include;

PFPS typically affects adolescents and adult people younger than 60 years
Women are more prone to developing this condition
Sports like running and jumping increase the tendency to develop PFSP
Weakness of the quadriceps muscle greatly contributes to developing this pain
An unstable patella increases the chance of getting PFS
Foot abnormalities are also a risk factor for pain

Diagnosis of Patellofemoral Pain Syndrome

The diagnosis of patellofemoral pain syndrome is usually clinical.⁴ Your doctor may:

Ask about your symptoms.
A detailed physical examination may be performed to evaluate joint inflammation, movement ranges, redness, weakness, and tenderness, comparing the affected side with the unaffected side. Examining gait, posture, and footwear as well.⁵
Plain radiographs are not helpful. However, if your pain shows no response, radiography is used to rule out other conditions, such as osteoarthritis, osteochondritis, and patellar fracture.

Treatment for Patellofemoral Pain Syndrome

Treatment for patellofemoral pain syndrome follows a conservative approach and is typically divided into two phases: the acute phase, focused on pain reduction, and the recovery phase, aimed at correcting the issue through a rehabilitation plan.

Acute Phase:

The primary goal during this phase is to alleviate pain and discomfort. This is achieved through:

Activity Modification

If you engage in sports or activities that stress the knee joint, such as running or squatting, it is important to avoid these activities to relieve pressure on the knee temporarily.

Medication

Your doctor may prescribe medication (analgesics) to manage pain and reduce its intensity.

Cold Therapy

Applying cold packs or using ice therapy is helpful as it can reduce swelling and alleviate pain.

Recovery Phase:

The recovery phase involves a personalized physical therapy plan to help you regain strength and flexibility for daily activities. It is the mainstay of treatment if you have patellofemoral pain syndrome. Under the guidance of a physical therapist, the plan includes ⁶

Exercise Therapy

They focus on strengthening your muscles around the hip and knee, especially the quadriceps. Exercise therapy for patellofemoral pain syndrome (PFPS) can significantly reduce pain, improve functional ability, and promote long-term recovery.⁷

Patellar Taping:

Patellar taping is helpful for correcting biomechanical issues that cause patellofemoral pain, such as the sideways movement of the patella. This technique reduces pain and pressure on the patella and supports the hip and knee muscles during movements like running.

Image showing taping technique for knee pain

However, taping alone is less effective than when combined with physical therapy or exercises.⁸

Bracing & Orthotics

Physical Therapists, after assessing your condition, may suggest braces or knee orthotics to correct biomechanics issues contributing to the pain.⁹

Prevention from Patellofemoral Pain Syndrome

Knee pain can arise from various factors. However, following these measures may help prevent patellofemoral pain syndrome:

Muscle Strength: Strong leg muscles support the knee joint and help prevent pain during movement.
Maintaining Body Weight: If you are overweight, try to lose some weight. Extra weight stresses large joints, including the knee joint, causing pain.
Move Safely: Always move, jump, run, or do daily activities with caution to avoid injuries.
Training Safely: Warm up and do gentle stretching exercises before training. This improves joint and muscle flexibility.
Proper Footwear: To avoid pain and discomfort, ensure you wear shoes that fit well and are suitable for your feet and activities.

Physical Therapy & Exercises for Patellofemoral Pain Syndrome

Physical therapy is essential for reducing pain and improving muscle strength and flexibility. It helps alleviate short- and long-term pain, whether at rest or during activity. Strengthening the muscles around the hip and knee significantly improves knee pain and function.

Straight Leg Raise:

Lie on your back with the unaffected leg slightly bent and the affected leg straight.
Lift the affected leg toward the ceiling.
Hold for 10 seconds, then lower the leg.
Repeat ten times for three sets.

Quadriceps Strengthening:

Sit with your back supported and legs straight.
Place a pillow or towel roll under the affected knee.
Press the towel down with your knee to strengthen the quadriceps.
Repeat ten times for three sets.

Abductor Strengthening:

Lie on your side with the affected side on top, and the knees bent.
Lift the affected knee toward the ceiling while keeping the hip stable.
Repeat ten times for three sets.

Surgery for Patellofemoral Pain Syndrome

Surgery for patellofemoral pain is rare. However, your doctor may recommend it if you experience severe knee pain and conservative treatments are ineffective.
Your doctor may perform an arthroscopy, a minimally invasive surgery. They make small incisions around the knee and insert a long tube with a camera to examine its internal structure. This allows them to identify and repair or remove damaged tissue. The procedure typically results in less pain and a faster recovery than traditional surgery.

Recovery time

Recovery from patellofemoral pain typically takes six weeks or more with conservative treatment. Enhancing muscle strength and flexibility around the hip and knee is crucial for a gradual return to activity. Your physical therapist will design a rehabilitation program based on your needs, muscle strength, and activity level, usually spanning three to four weeks.

Conclusion

Patellofemoral pain syndrome is a musculoskeletal condition causing pain at the front, behind, or around the kneecap. It develops gradually and can worsen without treatment. This condition typically causes pain when bending the knee during activities like stair climbing, running, or squatting. Diagnosis is based on clinical evaluation.
Conservative treatments, such as physical therapy, patella taping, and orthotics for biomechanical correction, are the primary approaches. Prevention is crucial and involves wearing well-fitted shoes and gradually increasing training intensity. Surgery is rarely needed or effective for this condition. Recovery from patellofemoral pain syndrome usually takes 3-4 weeks.

Refrences

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Patellofemoral Pain Syndrome: Causes, Symptoms & Prevention

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