What is patellofemoral pain syndrome?
Patellofemoral pain syndrome (PFPS), also called "Runners Knee", describes the symptom grouping of knee discomfort, swelling or clicking that is caused by excessive and/or imbalanced forces on the knee joint. The broad term “Patellofemoral pain syndrome” (PFPS) is a spectrum of signs and symptoms. The spectrum begins with non-painful functional mis-alignment of the knee cap and ends in severe patellofemoral arthritis.
How common is PFPS?
It is the most common cause of knee pain in the general population, affecting an estimated 25% of adults (1,5,23). Many PFPS patients are young and athletic (32). Data suggests the condition may affect nearly 10% of young athletes (2).
What causes patellofemoral pain syndrome?
PFPS is most common from muscular imbalance and cumulative overload. The issues typically begin as imbalances between the knee stabilizing muscles, which changes the forces on the patella (knee cap) and the surrounding tissues (cartilage). These stressors are compounded through activities of daily living, causing irritation and eventually wear to the patellofemoral cartilage.
PFPS is most commonly related to lateral tracking of the patella (4). The patella has a natural tendency to migrate laterally due to the pull of the quadriceps and the natural positioning of the hips, knees, ankles, and feet (5).
Compounding this problem it the fact that the patellofemoral orientation is largely determined by the hip and foot (6,7,40). Pes planus (flat feet) or over pronation causes internal rotation of the tibia and knee, placing stress on the lateral aspect of the knee cartilage- increasing one's risk of PFPS (8,24,40). Gluteus medius (Hip Abductor) weakness is associated with inward flare of the knee (knock knees) and lateral tracking of the kneecap (40-44). Current research suggests that patellar movement and tracking is more dependent on femur and tibia biomechanics than any individual knee muscle strength (26,40).
What are the symptoms of Patellofemoral Pain Syndrome?
PFPS patients generally present with dull pain around the kneecap that is worse with activites that load the joint, including prolonged walking, running, squatting, jumping, kneeling, arising from a seated position or stair climbing- especially walking down stairs or downhill. Swelling may accompany the pain. Damage of patellofemoral cartilage may result in clicking, intermittent locking, or giving way (27).
What are the risk factors for patellofemoral pain syndrome?
Risk factors include joint overload/ overuse, trauma, tight lateral knee capsule, excess movement of the patella, and muscular imbalance- particularly quadriceps or iliotibial band tightness and quadriceps weakness (9,28-30). Weakness in the quadriceps or hamstring muscles increases one’s risk of developing the problem three to five times more likely (24). Gluteal weakness is common and may contribute (12,33).
What are the best treatment options for patellofemoral pain?
Best practice guidelines suggest implementing exercise, bracing, foot orthoses and combined interventions of manual therapy and SMT (51,52).
Early management begins with avoiding aggravating factors and decreasing inflammation and transitions to long term correction of functional deficits (30). Reducing pain-provoking activities is an early priority, especially running, jumping and activities that induce a knock-knee position. Athletes should avoid allowing their knee to cross in front of their toes while squatting.
Electrotherapy and ice may be useful early on for reduction of pain and inflammation.
Myofascial release and stretching should be directed at hypertonic muscles.
Combining manual therapy with physical therapy reduces pain and improves function, especially when strengthening both hip and knee muscles (39). Exercise has a positive effect on PFPS patients, especially Gluteus medius and VMO (19, 40, 45-49). Eccentric exercises are also more effective than concentric.
Manipulation may be necessary for restrictions in the lumbosacral and lower extremity joints.
Taping the area may not address the source of the problem (20,21) yet, clinical practice guidelines do utilize corrective taping (51,52). Patellar tracking braces (i.e. BioSkin or PatellaPro) may lead to better outcomes (50-52).
Arch supports or custom orthotics may be necessary to correct hyperpronation (40). Research has shown that runners with PFPS benefit from a combination of exercise and foot orthotics (22). Runners should change shoes about every 250 miles.
At Creekside Chiropractic & Performance Center, we are highly trained to treat this condition. We are the only inter-disciplinary clinic providing services to Sheboygan, Sheboygan Falls, Plymouth, and Oostburg including chiropractic, manual therapy, myofascial release, ART (Active Release Technique), massage therapy, acupuncture, physiotherapy, rehabilitative exercise, nutritional counseling, personal training, and golf performance training under one roof. Utilizing these different services, we can help patients and clients reach the best outcomes and the best versions of themselves. Voted Best Chiropractor in Sheboygan by the Sheboygan Press.
Evidence Based-Patient Centered-Outcome Focused
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