What causes PFPS?
During activities that
involves knee bending (eg. climbing stairs, running, squatting), the
patella glides in a groove at the lower end of the thigh bone (femur).
The pressure on these structures can reach 2-8 times your body weight
during these activities. In patients with PFPS, the patella does not run
in the middle of this groove and usually tracks laterally, resulting in
increased pressure and irritation. Factors that may contribute to PFPS
Can PFPS be prevented?
- Muscle weakness and/or fatigue
- Muscle and soft tissue tightness
- Lower limb bone malalignment
- Overuse (eg. excessive training)
- Foot biomechanical abnormalities
Excessive training and lack
of proper conditioning of the muscles are often implicated in PFPS.
Hence, if you are at risk, you should adopt the following:
What will my doctor do?
- Strength & conditioning
Muscles that are
involved in running and other lower limb sports should be adequately
strengthened, so that they can meet the demands of your sporting and
This keeps the muscles and soft tissues elastic.
- Progressive training
Plan your training
programme. Give yourself ample time to reach your target mileage or
pace. Avoid rapid increases in volume or speed.
Check that your shoes are not
worn-out, as such shoes will not provide adequate support or shock
absorption. Choose a shoe with correct fit that is suitable for your
particular foot type.
Your doctor will
take a medical history, including your daily and physical activities,
and perform a physical examination. This will help to exclude other
possible causes of knee pain, such as meniscus tears, ligament or tendon
injuries. Medical imaging (i.e. ultrasound, magnetic resonance imaging
scans or X-rays) may be necessary. These can help the doctor assess the
alignment of your kneecap and cartilage thickness. You may also be asked
to run on a treadmill so that your gait can be assessed.How is PFPS Prevented?
- Strength, flexibility and conditioning exercises
Physiotherapy exercises can help regain the range of motion in your
knee and correct the muscle imbalances that affect patella movement. You
will be taught exercises to strengthen the core, hip and muscles around
the knee. Stretches (please see illustrations provided) to improve
flexibility will also be taught. Correct technique is essential, and you
should consult your physiotherapist if unsure, or if there is pain
during the exercise.
Sports tape may, occasionally, be used to enable you to exercise without pain.
- Activity modification
Treatment may require 3-6
months. During this period, you should minimise activities that may
worsen the condition. These include repetitive, high impact activities
that involve knee bending, such as running, stairs, hill-training, step
aerobics, roller blading and spinning. Adjust activities to a level that
you can comfortably tolerate. You can also replace high-impact
activities with exercises such as seated cycling, front crawl swimming,
deep water running, rowing and the elliptical trainer.
- Footwear modification
Your doctor may examine
your running shoes and provide advice on suitable shoe types. If
necessary, a podiatric consult for further assessment and orthotic
(insoles) fitting may be scheduled.
The following exercises
can be used to condition your body. Please warm-up before each
exercise. For all the exercises, perform 15-20 repetitions for each
side. Then repeat 2-3 times. Perform these exercises at least 2-3 days
every week but your exercise days should not be consecutive.Lungesee pictures
Wall squatsee pictures
- Do not bend your front knee more than 90 degrees.
- Keep the knee in line with your toes.
- Keep the knee above the ankle.
- Keep knees over ankle.
- Squat should be pain-free.
- Tighten your VMO before the rest of the quadriceps. Use your hand to help isolate the muscle.
- Hold 30 sec.
- Increase the duration of the squat until it reaches 3-5 mins.
The following exercises can be
used to condition your body. Please warm-up before each exercise. For
all the exercises, perform 15-20 repetitions for each side. Then repeat
2-3 times. Perform these exercises at least 2-3 days every week but your
exercise days should not be consecutive.