Why Does the Front of My Knee Hurt? Understanding Patellofemoral Pain Syndrome

Patellofemoral Pain Syndrome is a common cause of discomfort at the front of the knee. It often results from poor movement mechanics, muscular imbalance, or repetitive stress on the joint. While frequently associated with active individuals, it can affect anyone with increased knee demand. This article outlines typical causes, effective management strategies, and the role of bracing and rehabilitation exercises in restoring knee function.

An Overview of the Condition

Patellofemoral Pain Syndrome (PFPS), commonly referred to as “runner’s knee,” is one of the most frequent causes of anterior knee pain, especially among physically active individuals. It occurs when the patella (kneecap) does not track properly along the trochlear groove of the femur during movement, leading to irritation of the surrounding soft tissues or the articular cartilage beneath the patella. PFPS is not typically associated with structural damage but rather functional imbalances, making it a diagnosis of exclusion. It is most prevalent in adolescents, young adults, and athletes, particularly females, and is strongly linked to overuse and biomechanical dysfunction of the lower extremity.

Symptoms of PFPS often develop gradually and may vary depending on activity level. Common symptoms include:

Anterior knee pain: A dull, aching pain located around or behind the kneecap, especially during activities that load the knee in flexion.
Crepitus or grinding sensation: Some individuals may feel or hear grinding when bending or straightening the knee.
Mild swelling or tenderness: There may be local tenderness around the patella, and in some cases, mild joint effusion.
Instability or giving way: Though less common, some may report a sense of the knee being unstable or weak during weight-bearing tasks.
Pain with stairs or squatting: Climbing stairs, kneeling, or squatting often aggravates symptoms due to increased patellofemoral joint compression.
Pain after prolonged sitting: Known as the “theater sign,” discomfort may arise after sitting with knees bent for long periods.

What Cause Patellofemoral Pain Syndrome

PFPS is considered a multifactorial condition resulting from poor patellar tracking, muscular imbalance, and excessive joint loading. Common causes include:

Overuse and repetitive loading: High-frequency activities involving knee flexion, such as running or jumping, can lead to cumulative stress on the patellofemoral joint.
Poor patellar tracking: Lateral displacement or tilt of the patella due to muscle imbalance or tight lateral structures can increase localized joint pressure and irritation.
Quadriceps weakness or imbalance: Weakness or delayed activation of the vastus medialis obliquus (VMO) can cause the patella to drift laterally during knee extension.
Tight lateral structures: Tightness in the iliotibial (IT) band, lateral retinaculum, or hamstrings alters normal joint biomechanics.
Foot and hip mechanics: Excessive foot pronation and weak hip abductors or external rotators can lead to poor alignment and increased dynamic valgus, contributing to abnormal patellar motion.
Improper training or technique: Rapid increases in activity, poor running or lifting form, and improper footwear may aggravate joint loading and promote symptom development.
Anatomical predisposition: Structural abnormalities such as a high Q-angle, shallow trochlear groove, or patella alta can increase patellofemoral joint stress.

Management of Patellofemoral Pain Syndrome

Effective treatment for PFPS focuses on reducing pain, correcting biomechanical imbalances, and restoring functional movement. Management strategies include:

Activity modification: Temporarily reduce or modify aggravating activities such as running, squatting, or jumping to allow symptoms to subside.
Ice therapy and NSAIDs: Ice packs and nonsteroidal anti-inflammatory drugs can help manage acute pain and inflammation.
Physical therapy: A structured rehab program targeting quadriceps strengthening (especially the VMO), hip stabilizers, and flexibility is the mainstay of treatment.
Bracing: A patellar tracking brace or lateral buttress knee support can help stabilize the kneecap, reduce lateral deviation, and alleviate joint stress during activity.
Bracing: A patellar tracking brace or lateral buttress knee support can help stabilize the kneecap, reduce lateral deviation, and alleviate joint stress during activity.
Stretching: Targeted stretches for the IT band, hamstrings, and calf muscles help reduce abnormal forces on the patella.
Taping techniques: Patellar taping (e.g., McConnell taping) can help improve tracking and provide short-term pain relief during movement.
Education and load management: Educating the patient on proper movement mechanics, posture, and gradual return to sport is essential to prevent recurrence.

How Brace Help Patellofemoral Pain Syndrome

Bracing can be an effective adjunctive strategy in the conservative management of patellofemoral pain syndrome (PFPS), particularly when integrated with exercise therapy and load management. Patellar tracking braces are designed to optimize joint alignment, reduce pain, and support functional recovery. The therapeutic effects of bracing include:

Patellar stabilization: Patellar braces equipped with lateral buttresses or dynamic realignment straps help maintain appropriate patellar tracking within the femoral trochlear groove during knee flexion and extension. This reduces lateral patellar displacement and associated joint stress.
Pain reduction: By improving patellofemoral alignment and minimizing maltracking, bracing can reduce mechanical irritation of the subpatellar tissues, resulting in decreased anterior knee pain during daily activities and sport-specific movements.
Joint support and proprioceptive input: External support from the brace provides mechanical stability while enhancing proprioceptive feedback. This neurosensory input may facilitate improved motor control and coordination of the quadriceps, particularly during dynamic or load-bearing tasks.
Compression and inflammation control: Many patellofemoral braces offer mild circumferential compression, which can assist in controlling joint effusion, enhancing circulation, and limiting secondary soft tissue irritation.
Improved movement confidence: The structural support and perceived protection provided by the brace can enhance patient confidence during movement, reducing fear-avoidance behavior and encouraging earlier return to activity or rehabilitation participation.

Recommended Exercises for Long-Term Support

Rehabilitation exercises for PFPS aim to strengthen the muscles that stabilize the patella and improve overall lower limb alignment. Common exercises include:

■ Quadriceps Strengthening

Straight leg raises and terminal knee extensions help activate the quadriceps, particularly the VMO.

■ Hip Strengthening

Side-lying leg lifts, clamshells, and band walks target the gluteus medius and external rotators to improve dynamic knee alignment.

■ Stretching Exercises

Regular stretching of the IT band, hamstrings, hip flexors, and calves can reduce excessive tension on the knee joint.

■ Step-downs

Controlled step-down exercises help train eccentric strength and proper knee alignment during functional movement.

■ Mini Squats or Wall Sits

These help restore quadriceps endurance while minimizing patellofemoral joint load when performed within a pain-free range.

■ Balance and Proprioception

Single-leg stance and balance board exercises improve neuromuscular control and prevent future dysfunction.

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