Kneecap (Patellofemoral) Pain

What is it?

The kneecap (patella) is situated in front of the knee and is connected to the quadriceps (thigh muscles) as they taper down to connect to the tibia (shin bone). The patella tendon attaches to the lower pole of the patella and joins the upper tibia. The patella bone glides along a groove on the underlying femur (thigh bone) whenever the knee bends and straightens. Pain can be experienced around the patella when it doesn’t track correctly in its groove. Depending on how the patella sits in its groove varying amounts of pressure are exerted on the under surface of the patella. This abnormal pressure can lead to changes in the cartilage on the back of the knee cap and result in knee pain. The pain commonly comes on over time and is worse with activities which involve a high amount of knee bending i.e. squatting or going up and down stairs or perhaps sitting for prolonged periods of time.

Causes

There are many factors which can predispose to developing patellofemoral pain and they can be classified into four groups:
 

• Biomechanics – changes to the normal ranges of joint positions i.e. excessive inward rotation of the hips/ shins (femoral anteversion / internal tibial rotation), increased rolling in of the foot (pronation)

• Muscle tightness – Tight calf muscles, hamstrings and thigh muscles and tissues which run down the outside of the knee (Iliotibial band, vastus lateralis and adjoining fascia) can impose abnormal stresses on the patella which can alter its normal direction of pull.

• Muscle weakness - Poor strength and stability of the muscles around the inside of the knee (vastus medialis oblique) and those which work to stabilize and outwardly rotate the hip joint (gluteus medius) can lead to poor biomechanics

• Overuse or activity training error – i.e. increasing running training speed, intensity or distance too quickly or changing training environment without adequate acclimatisation i.e. hill running when used to running on the flat.
   

Treatment

Following a thorough examination and assessment of the presenting problem, advice and treatment may include the following:

• Ice and rest from aggravating activities

• Taping to correct patella alignment and reduce pain

• Electrotherapy i.e. ultrasound, laser and interferential to promote healing and reduce pain

• Acupuncture for pain relief, control of inflammation and restore normal muscle tone

• Correction of anatomical abnormalities if present with orthotics etc

• Soft tissue and joint manipulation to address tight and overactive muscles & any restriction of normal movement

• Progression of a individually tailored rehabilitation programme including appropriate stability and stretching exercises