Anterior knee pain (pain in the front of the knee) is the most common form of knee pain which physiotherapists deal with.1 Patellofemoral pain and patellar tendinopathy are the most common causes. There are also other causes of knee pain that your physiotherapist will also consider when doing an assessment, especially when there is discomfort in the front of the knee. These conditions are:
- bursitis
- fat pad impingement
- synovial plica
- osteoarthritis and
- instability in the knee
What is the anatomy of the knee? 
The knee joint is one of the biggest joints in the body, consisting of the end of the femur (thigh bone), the upper end of the tibia (shin bone) and the patella (knee cap). There are various ligaments, tendons, bursa, synovial fluid and cartilage that connect to or around the knee joint.
We will now have a look at two forms of anterior knee pain – patellofemoral pain syndrome (PFPS) and patellofemoral tendinopathy.
What are the causes of Patellofemoral Pain (PFP)?
Also known as “runners’ knee”, this refers to pain experienced behind the knee cap where the knee cap (patella) joins with the thigh bone (femur). The most common causes are poor alignment (that is, the position of the patella itself), an overuse injury and bio-mechanics of the joint. Poor bio-mechanics are caused by:
- Muscle imbalance between the quadriceps and hamstrings
- Weak hip muscles
- Poor foot posture
What are the signs and symptoms?
- Gradual onset of pain behind the knee cap
- Increased pain mostly in weight-bearing activities (going up and down stairs, running, squatting)
- A dull aching pain in front of the knee (diffused pain)
- Pain after sitting for long periods at a time
What can be done to help PFP?
Physiotherapy
- Thorough assessment
- Specific exercises for strengthening weakened muscles, control and bio-mechanics
- Soft tissue release for tight muscles in the legs
- Pain relief options, such as taping.
Activity modification
This may be needed for patients who are long-distance runners.
Changing footwear
Referral to a podiatrist to provide orthotic foot support if necessary.
Medication – such as NSAIDS (non-steroidal anti-inflammatory drugs).
What are the causes of Patellar Tendinopathy?
Patellar tendinopathy is sometimes confused with PFP due to the pain being in a similar area of the knee. This kind of hurt is localised to the lower pole of the knee cap over the patella tendon and is aggravated by weight-bearing activities. Some causes are:
- Foot posture
- Poor bio-mechanics
- Decreased dorsiflexion range
- Poor quadriceps to hamstring ratio
- Weak hip and pelvic muscles
- A rapid increase in load
What are the signs and symptoms?
- Pain localised to the inferior pole of the knee cap/patella tendon
- Pain aggravated by load, especially increased with high energy activities
- Pain and stiffness in and around the knee
- Loss of strength
- There may be inflammation (Thickening of the tendon)
- A report of increased pain after exercising or the next day
What can be done to manage Patellar tendinopathy?
Physiotherapy
- R.I.C.E treatment and avoid aggravating activity in the early phases
- Treatment for pain and inflammation
- Strapping to unload the tendon
- Specific exercises (Eccentric>isometric>concentric)
- Laser therapy
Medication – non-steroidal anti-inflammatories (there are very controversial views on this option).
This article was updated by Rikki Malherbe from our Paulshof branch. Set up an assessment appointment if you have been experiencing this kind of knee pain so that the appropriate diagnosis and treatment can be discussed.
References:
- Clinical Sports Medicine 5th Edition – Brukner & Khan
- Knee Anatomy, Biomechanics & Pathology – SPT (2016)
- Physioworks Brisbane, Australia 2019 – Patella Tendinopathy
- Orthoinfo.aaos.org 2019 – Patellofemoral Pain
- Physiopedia.com 2019 – Patella Tendinopathy