Patellofemoral Syndrome

What is it?

Patellofemoral syndrome is where pain originating from under the knee cap (called the patella) is caused when it doesn’t glide up and down on the knee correctly, which can be due to by many different reasons. Alignment or overuse problems of the patella can lead to wear and tear of the cartilage behind the patella. This causes pain, weakness and swelling of the knee joint.

• Patients usually report:

• Sensation of the patella slipping

• Pain around the front part of the knee or along the edges of the kneecap

• Some people experience pain with going down hills or stairs

• Keeping the knee bent for long periods may cause pain

• The knee may grind or crunch, pop or click when you bend it such as when squatting or going up/down stairs

These problems can affect people of all ages.

Mechanism of Injury

• Problems usually occur when the patella suffers wear and tear due to a muscle imbalance. This usually occurs when the inside quadricep muscle called vastus medialis (also known as VMO), is weakened and/or some structures on the outside of the knee, such as the vastus lateralis another quadricep muscle, is too tight and fails to hold the patella in the correct position. 

• When muscles are weak for any reason, this causes the quadriceps muscles to pull the patella to more side than the other which in turn, causes more pressure and damage to the cartilage on one side of the knee and patella.

Common Management Techniques

Once a diagnosis is made, management of patellofemoral pain includes educating about:

• Reducing or stopping activities that provoke pain and only resuming it when the pain has disappeared

• Icing for 20 minutes after exercising to decrease pain and swelling

• Speak with their doctor with regards to medical management e.g. NSAID’s

• Self-patella mobilisations and self-taping

• Bracing the knee

• Address faulty lower limb and patellofemoral biomechanics

• Orthotic and insole devices

• Appropriate stretching techniques around the hip, knee and ankle

• Use of massage and trigger point releases through tight structures

Prognosis

Patellofemoral syndrome is considered a self-limiting disorder. It is important that all the biomechanical factors that are contributing to the disorder are addressed and considered, and this may include other joints such as the hip and ankle. 

For some people a course of physiotherapy for 6 weeks may be suitable, others may be a year. 

Some patients who do not respond to conservative management may need to go on to having surgery such as an arthroscopy if structures such as cartilage are severely damaged or a lateral release if the patella problems are due to malalignment and a knee reconstruction if misalignment is severe.