Physical Therapist's Guide to
Medial Patellofemoral Ligament (MPFL) Injury
The medial patellofemoral ligament (MPFL) helps to keep the kneecap centered along the front of the knee, so that it tracks well during knee movements. MPFL injuries typically occur during a forceful traumatic kneecap dislocation. This injury is most common among young, active females. Depending on the severity of an MPFL injury, treatment may involve surgical reconstruction, followed by physical therapy. Physical therapists design treatment programs for individuals with MPFL injuries to help them gently restore their knee strength and function.
What is a Medial Patellofemoral Injury?
The medial patellofemoral ligament is a broad structure located on the inside of the knee joint. It connects the kneecap (patella) to the thigh bone (femur). The primary purpose of the MPFL is to provide stability to the kneecap; it provides restraint to any movement toward the outside of the knee. It also helps keep the kneecap in position, as the knee bends and straightens.
How Does it Feel?
Common signs and symptoms that may occur with an MPFL injury include:
- Feeling the knee “giving way” or “buckling” during activity.
- Feeling like the kneecap is sliding out to the side during knee movement.
- Swelling of the knee following activity.
- Restricted joint movement (range of motion).
- Pain when moving the joint.
- Tenderness to touch along the affected joint.
- Pain, stiffness, or "locking," after sitting with the knee bent or straight for a prolonged period of time.
How Is It Diagnosed?
When you first go to see your physician or physical therapist, the therapist will review your medical history, ask you how and when you injured your knee, and ask you to describe your symptoms. Your physical therapist will perform a comprehensive physical exam of your knee, assessing different measures, such as range of motion, strength, and flexibility. The physical therapist likely will manipulate your knee, placing it in certain positions to try to pinpoint which specific structures may be injured. If an MPFL injury is suspected, your physical therapist may assess the mobility of your kneecap, specifically to note if it moves more to the outside compared to your uninjured knee. Additionally, you may be asked to briefly perform or describe the activities that cause your pain.
Imaging techniques, such as x-rays or an MRI, may be required to gain a more thorough and objective evaluation of all of the structures of the knee joint. Your physical therapist may refer you to an orthopedic physician for further investigation, if needed.
How Can a Physical Therapist Help?
Your physical therapist will design an individualized treatment program specific to the exact nature of your condition and your goals. Your treatment may include:
Range-of-Motion Exercises. Many individuals who develop MPFL laxity or injury are naturally flexible. However, when there is an injury to a joint, our bodies tend to become guarded, which may limit the joint’s range of motion. Your physical therapist will assess your motion compared to expected normal motion and the motion of the uninvolved joint on the other side of your body. Your physical therapist will prescribe range-of-motion exercises to help restore natural movement to the knee.
Muscle Strengthening. Strengthening the muscles around the injured joint is an essential part of the rehabilitation program. As the muscles along the front and back of the thigh (the quadriceps and hamstrings) cross the knee joint, they help control the motion and forces that are applied to the bones of the knee. When there is an injury to a joint that causes pain and swelling, muscles often become inhibited, which means they may not function at their normal capacity. Strengthening the hip and core muscles also can help balance the amount of force on the joints of the leg, particularly during walking or running. Your physical therapist will assess these different muscle groups, compare the strength in each limb, and prescribe specific exercises to target your areas of weakness.
Manual Therapy. Physical therapists are trained in manual (hands-on) therapy. Your physical therapist will gently move and manipulate your muscles and joints to improve their motion, flexibility, and strength. These techniques can target areas that are difficult to treat on your own. For patients with MPFL injuries, manual therapy techniques can help restore the joint's normal motion, and support proper movement patterns during joint motion and functional movements. Physical therapists with experience who treat individuals following MPFL injury will be aware of which manual techniques are safe, and which should be avoided, particularly after a surgical reconstruction.
Modalities. Your physical therapist may recommend therapeutic modalities, such as ice and heat, to aid in pain management.
Bracing. Compressive sleeves placed around the affected joint may help reduce pain and swelling. There are specific braces for individuals with too much kneecap motion that provide extra support through a buttress-like pad around the edge of the kneecap. In the event that surgery is required, braces may be used to control the amount of motion that is allowed as the postsurgical rehabilitation program progresses. For example, if an MPFL injury at the knee joint is treated surgically, a brace will keep the knee straight for the first several weeks after surgery.
Activity Guidance. Your physical therapist will help you return to activities in a safe and structured manner, using your symptoms as a guide to protect your knee joint as it heals. Your physical therapist will consider each stage of healing of the MPFL and recommend appropriate exercises to address your needs at each stage, and maximize the health of your knee joint.
If Surgery Is Required
When conservative management strategies are not successful in the treatment of MPFL injury, or in cases where there are other associated injuries, surgery may be considered. The goal of surgical intervention is to restore the integrity of the injured ligament, so that it can properly provide stability to the knee. There are many factors to consider when determining the appropriate surgical treatment, including the nature of your condition, your age, and your desired activity level. Your physical therapist will refer you to an orthopedic surgeon to discuss your surgical options.
If surgery is required to reconstruct your MPFL, you will spend several months in physical therapy after your surgery. Your physical therapist will help you progress through the stages of restoring normal range of motion, strength, and function. Rehabilitation following knee ligament surgeries is very important, as physical therapists are skilled at knowing when and how to progress patients safely after surgery. Your physical therapist will communicate closely with your surgeon to ensure that you are on track to a full recovery.
Can this Injury or Condition be Prevented?
Like many injuries and conditions, there are some factors that can be controlled and others that cannot when it comes to preventing MPFL injuries. In some cases, MPFL injuries are caused by a traumatic event, such as a sports injury. Occasionally, individuals with excessive joint or ligament looseness, or laxity, may suffer a nontraumatic MPFL injury; this may occur because the ligament has greater than normal flexibility and is not able to properly stabilize the knee joint during activities. Individuals who are involved in sports and other physical activities should make sure to properly strengthen their leg muscles to help support the structures around the knee joint. It is important to modify your activity and contact your physical therapist soon after you first feel pain.
Once you are involved in a rehabilitation program, your physical therapist will help you determine when you are ready to progress back to your previous activity level. Your physical therapist will make sure your body is ready to handle the demands of your activities, so that your injury does not return. That program will include guidance on which activities should be chosen and which should be avoided. You will also receive a program to perform at home that will help you maintain the improvements that you gained during rehabilitation.
Real Life Experiences
Casey is a 14-year-old basketball and volleyball player. She comes from a long line of tall, athletic family members, and as a high school freshman, she is taller than most kids in her grade. Due to her height and keen athletic ability, Casey has been playing on club basketball and volleyball teams for several years, and this year, she made the varsity team in both sports. She loves competing, and has high hopes for playing at the next level.
Last Friday night, Casey was already breaking the school record for the number of rebounds by a freshman by the third quarter of her team's basketball game against a local rival. The game was tied in the fourth quarter; Casey had played the entire game, but was not willing to consider subbing out. On a fast break down the court, she went up to lay the ball in and landed awkwardly on her left knee. Falling to the floor, she felt her kneecap pop out to the side of her knee and then back in. Unfortunately, Casey was unable to finish the game. Her team lost in the final minutes.
The next day, Casey’s knee remained very swollen and painful; she was unable to walk the halls at school without her knee feeling like it was going to give way. After a visit to the orthopedist and having an MRI, it was determined that Casey had suffered a rupture to her MPFL. Being a young, athletic individual, it was recommended that she have surgical reconstruction, so that she could have a stable knee and return to basketball and volleyball at a high level.
Following surgery, Casey began physical therapy right away. Her physical therapist used different techniques to help Casey decrease the swelling at her knee, and regain her range of motion and strength. She explained to Casey how to protect the repaired ligament, so that it would have the best chance to heal properly. When Casey demonstrated adequate motion and strength, her physical therapist allowed her to begin walking without crutches, and began working on activities, like balance, squatting, and progressive strengthening exercises. She designed an individual home-exercise program for Casey to continue her healing at home. Casey worked very hard during her rehabilitation sessions and with her home-exercise program.
Within a few months, Casey was back to running and jumping, and then started practicing different sport-specific activities. At a follow-up appointment several months after her initial injury, it was determined that Casey's MPFL was strong again and that she met the functional requirements to return to sports.
Casey gradually began practicing with her volleyball team. At first, it felt bizarre to be back on the court after not playing for so long, but she quickly learned to love it again. She kept doing her exercises because she knew that she had a higher risk of another knee injury, due to her previous one. She could tell that her body was stronger than ever and wanted to keep it that way! A few weeks into the volleyball season, she nailed the winning point against her school's cross-town rivals—and landed like a champ!
What Kind of Physical Therapist Do I Need?
All physical therapists are prepared through education and clinical experience to treat a variety of conditions or injuries. You may want to consider:
- A physical therapist who is experienced in treating people with orthopedic or musculoskeletal injuries.
- A physical therapist who is a board-certified specialist or who has completed a residency in orthopedic or sports physical therapy, as they will have advanced knowledge, experience, and skills that apply to an athletic population.
- You can find physical therapists who have these and other credentials by using Find a PT, the online tool built by the American Physical Therapy Association to help you search for physical therapists with specific clinical expertise in your geographic area.
General tips when you're looking for a physical therapist (or any other health care provider):
- Get recommendations from family and friends or from other health care providers.
- When you contact a physical therapy clinic for an appointment, ask about the physical therapists' experience in helping active individuals.
- During your first visit with the physical therapist, be prepared to describe your symptoms in as much detail as possible, and report what activities make your symptoms worse.
The American Physical Therapy Association (APTA) believes that consumers should have access to information that could help them make health care decisions, and also prepare them for their visit with their health care provider.
The following articles provide some of the best scientific evidence related to physical therapy treatment of medial patellofemoral ligament injuries. The articles report recent research and give an overview of the standards of practice both in the United States and internationally. The article titles are linked either to a PubMed* abstract of the article or to free full text, so that you can read it or print out a copy to bring with you to your health care provider.
Ries Z, Bollier M. Patellofemoral instability in active adolescents. J Knee Surg. 2015;28(4):265-277. Article Summary on PubMed.
Arendt EA, Moeller A, Agel J. Clinical outcomes of medial patellofemoral ligament repair in recurrent (chronic) lateral patella dislocations. Knee Surg Sports Traumatol Arthrosc. 2011;19(11):1909-1914. Article Summary on PubMed.
Fisher B, Nyland J, Brand E, Curtin B. Medial patellofemoral ligament reconstruction for recurrent patellar dislocation: a systematic review including rehabilitation and return-to-sports efficacy. Arthroscopy. 2010;26(10):1384–1394. Article Summary on PubMed.
Arendt EA, Fithian DC, Cohen E. Current concepts of lateral patella dislocation. Clin Sports Med. 2002;21(3):499-519. Article Summary on PubMed.
* PubMed is a free online resource developed by the National Center for Biotechnology Information. PubMed contains millions of citations to biomedical literature, including citations in the National Library of Medicine’s MEDLINE database.