Patellofemoral pain syndrome (PFPS) is a very common knee condition, making up about 90% of all knee pain. It affects a wide age bracket, generally from 18 years of age through to 50 years of age and tends to creep up on you due to overuse, but it could also occur as a result of another specific injury. For example, somebody who has suffered an ACL (anterior cruciate ligament) injury might go on to develop secondary PFPS.
The pain can be felt at the front of the knee joint itself, where the knee cap (the patella) connects to the thigh bone (the femur), rather than from a muscle or nerve, etc. This is illustrated in the image below.
There is usually a problem with how the knee cap glides along the end of the thigh bone. This is called ‘maltracking’ and it can occur for a number of reasons, such as:
- Pain and swelling, which inhibits muscle activation
- Poor body mechanics, e.g. flat feet or knock knees
- Soft tissue tightness, e.g. muscle, or connective tissue
- Decreased thigh muscle strength
- Poor technique when exercising, e.g. toes pointing forward with squats
Signs and Symptoms
In most cases, patellofemoral pain syndrome comes on gradually, and it can be attributed to a recent change in activity. For example, somebody might have started running 4 times per week instead of twice per week, or perhaps they’ve started running on a footpath instead of a grassy oval or perhaps they have gone from walking to running suddenly. It is also possible to develop PFPS after having knee surgery, for example, an ACL repair.
The pain from PFPS is usually felt at the front of the knee, more so on the inside (so, if somebody has PFPS in their right knee, they will probably feel that pain at the front of the knee but a bit to the left.) The pain is usually described as a vague or diffuse ache that comes on with walking, standing up from a chair, climbing stairs or hills, squatting, kneeling, or prolonged sitting.
Your Body Rhythm Physiotherapist can gather useful information simply by having a look at you. Certain muscles may appear less bulky than ideal, such as the quadriceps, especially the inner part which is called the vastus medialis (shown in the image below).
Alignment at the knee is another clue for diagnosing PFPS, for example some people might have inward facing knees, or knock knees. Furthermore, flat feet can affect the alignment at your knee and contribute to your pain.
Your physiotherapist may notice these abnormalities when you stand still, but sometimes it only becomes evident once you start moving. Therefore, they may ask you to perform certain activities such as walking, squatting, or hopping.
Your physiotherapist will then conduct a hands-on assessment, and this may reveal tenderness when pressing on the underside of the knee cap. Other assessment findings may include restricted knee joint movement, muscular tightness, and muscular weakness.
Treatment is always individualised and will be based on each person’s assessment findings. Some examples of treatment methods will be given here, but this is not an exhaustive list. As a general rule, you can expect your physiotherapist to combine hands-on techniques with a home exercise program.
Joint mobilisation is a type of hands-on technique which is used to free up a stiff joint. Remember that PFPS is a problem of how the kneecap moves, and it is often stiff into certain directions. If this is the case, your physiotherapist can use mobilisation techniques to improve how the kneecap moves. Additionally, they can treat muscles that attach to the kneecap, which if tight, will restrict kneecap movement.
It is vital that the patient follows up their hands-on treatment with an exercise program, particularly when it comes to strengthening exercises, because while a physio can help to mobilise a joint, or relax a tight muscle, they can’t strengthen a muscle for you. Foam rolling is an effective method of increasing mobility and closely resembles a massage technique. Strengthening will often start in a simple fashion, by isolating a weak muscle. For example, your physiotherapist may give you a resistance band to get your thigh muscles stronger. The pictures below demonstrate the use of a foam roller.
Hands-on therapy and exercises will make up the bulk of your treatment, however, there are some adjunct treatment methods that have their place too. Athletic tape can be applied to the knee (as shown in the picture below) in order to decrease pain and improve how the kneecap tracks against the end of the thigh bone. The mechanics at your foot affect the mechanics at your knee, and vice versa. Therefore, some people with knee pain will benefit from orthotics, which your physiotherapist can provide (also shown below).
That is patellofemoral pain syndrome in a nutshell. If you think you are experiencing PFPS, or any other type of knee pain for that matter, best to book in at your local Body Rhythm Physiotherapy for assessment, diagnosis, and treatment.
Written by Body Rhythm Physiotherapist Sean O’Brien.
Brukner, P., & Khan, K. (2011). Clinical sports medicine. (4th ed.). North Ryde, NSW: McGraw-Hill Education.