PT Classroom - Understanding Patellofemoral Dysfunction ׀ by Kate Grace, PT, OPA-C & Annie Fonte, MBA


Kate Grace is a thought leading Physical Therapist and Orthopedic Physician Assistant who travels the world teaching healthcare professionals about the proper diagnosis and treatment of patellofemoral dysfunction. A graduate of The Ohio State University’s prestigious Physical Therapy Program, Kate founded Kate Grace Physical Therapy in San Diego, California, in 1985, where she treats patients with acute and surgical orthopedic injuries, postural dysfunctions, and athletic and industrial injures of the spine and extremities. Kate’s unique interest in physical therapy goes back to her childhood, when at the age of 12, she was diagnosed with Patellofemoral Dysfunction. After treating patellofemoral patients and researching the condition for the past 25 years, Kate and her associates, including Annie Fonte, founded OrthoRx, Inc. and developed the OnTrackŪ System, a patented unique, non-surgical method for the management of patellofemoral dysfunction.

Understanding Patellofemoral Dysfunction


Finding the most effective and efficient way to treat patellofemoral pain has been a goal of physical therapists and orthopedic surgeons for years. Traditional bracing and surgery have proven to be inconsistent in providing pain relief, so many people with patellofemoral dysfunction (PFD) endure pain on a regular basis with no treatment options but to modify their activity, grim and bear it.

It is estimated that every year 13 million people visit their doctor with knee pain, of those 3.5 million are diagnosed with PFD. And, of the 3.5 million who are diagnosed with PFD, 3.2 million of them have a bony malalignment or patellofemoral malalignment. Patellofemoral dysfunction can be aggravated by insufficient quadriceps strength, increased femoral rotation, postural malalignments, and soft-tissue changes.

Most often, people with patellofemoral dysfunction experience pain when going down stairs, squatting, during prolonged sitting and when rising from sitting and vigorous sports activities. The reason these movements or conditions are painful is because people are eccentrically loading the knee joint. This can put three to seven times your body weight of pressure on the patella. The patella can track poorly for a long period of time before the improper mechanics take their toll. However, once the pain and low grade inflammation develop it is difficult to reverse.

People with patellofemoral pain generally have one of four patellar malalignments.

Tilt: Patellar tilt is typically toward the outside or lateral side of the leg. When lateral tilt occurs, the surface of the kneecap is at an abnormal angle at the end of the femur. As a result, the kneecap rides over the outside edge of the bony prominence of the femur resulting in wearing down of the kneecap cartilage. One of the symptoms of tilt is a weakened Vastus Medialis Oblique (VMO) muscle. Since the VMO is essential to keeping the patella tracking correctly, its lack of strength will contribute to an even greater malalignment.

Glide: With a glide condition, the entire kneecap is shifted to the outside of the joint. Glide can be seen by comparing the inside and outside portions of the kneecap to its position relative to the femur. Once again, a glide condition will cause irritation to the underside of the patella and the surface of the femur bone.

A/P: Anterior/Posterior malalignment occurs when the lower edge of the kneecap is tilted downward toward the tibia. The lower edge of the kneecap becomes buried in the fat pad below the patella and puts pressure on the patellar tendon. This can result in pain centered at the lower edge of the kneecap, irritation to the fat pad and inflammation of the patellar tendon.

Rotation: In a knee with rotation malalignment, the kneecap’s midline is not parallel to the longitudinal axis of the femur. Rotation of the kneecap can result in wear and tear on the patellar cartilage and a disadvantaged kneecap position which will inhibit the VMO muscle’s ability to contract.

Current treatments for patellofemoral dysfunction range from therapeutic exercise to strengthen the quadriceps, taping, bracing, and surgery. Therapeutic exercise and taping have their merits if the patient does NOT have one or more of the four malalignments addressed above. Exercise can serve to strengthen weak or de-conditioned quadriceps muscles and taping can effectively address soft tissue challenges. The best orthopedic surgeons do not operate until all means of physical therapy have been exhausted. In some cases, surgery may be an option. There are two surgeries commonly performed to do patellar realignments. The less invasive measure is an arthroscopic surgery in which the lateral retinaculum is released by being cut, with the hope that it will stop pulling on the patella, thus allowing it to find its anatomically correct location. It is paramount that physical therapy is started day-1 post-op in order to eliminate the swelling in the knee joint and to ensure that the lateral retinaculum does not scar down.

The second surgical method often selected is an open procedure called an extensor mechanism realignment. This process entails lifting the patellar tendon off the tibia at the tibial tubercle where the tendon attaches. The tendon is then moved medially and stapled back to the bone (tibia). The second step of this surgery is to do a lateral release and then finally a VMO advancement. The VMO advancement involves cutting the VMO muscle off the patella and advancing it distally on the patella in an attempt to enhance the horizontal pull of the VMO fibers. This is an extensive surgery and requires approximately 6 to 8 months of post-op physical therapy.

Physical therapists are the musculoskeletal and therapeutic exercise experts who can help the patellofemoral patients manage this very challenging malady. We as therapists must go beyond only taking someone’s pain away. We need to realize that we can have a profound effect on people’s lives by enabling them to perform activities and sports, or to pursue the careers of their dreams. As clinicians, we need to begin our treatment with this patient with a thorough evaluation and examination to identify the factors contributing to a patient’s PFD. It is also essential that we perform a comparable sign prior to treating our patients to determine the effectiveness of our chosen treatment method. A comparable sign reproduces the patient’s pain, and the treatment method must greatly alleviate or eliminate the patient’s pain.

There are two things we must do for the PFD patient, and it is important that they are done in this order:
1) Realign the patella back in the interchondylar groove, put a constant stretch on the lateral retinaculum, and eliminate the pain cycle.
2) Then, in this pain-free environment, develop a thorough manual therapy and therapeutic exercise program to maximize the function of the quadriceps muscles, particularly the VMO.

When these two steps are accomplished you will be successful in resolving PFD and returning your patients back to functional and athletic activities long-term.

Last revised: July 13, 2010
By Kate Grace, PT, OPA-C & Annie Fonte, MBA

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