Patellofemoral pain syndrome (PFPS) is a common condition suffered amongst both athletes and the general public. It is characterised by pain around or underneath the kneecap (patella). This pain may be the result of some direct trauma to the knee, or often the patient describes a gradual and progressive onset of pain without any specific traumatic event.
Pain associated with PFPS typically arises with activities such as climbing up or down stairs, rising from chairs, kneeling and squatting. Another common complaint associated with PFPS is the phenomenon of deep aching pain associated with prolonged sitting with the knee in a bent position, termed the movie-goers or theatre sign. Often, these aching symptoms resolve quickly by straightening the knee or walking.
The patellofemoral joint is composed of the kneecap, or patella and the underlying thighbone, or femur. The under-surface of the patella glides smoothly within a shallow groove that is created by the femur. When the knee bends and straightens, the patella slides up and down along this groove.
The patellofemoral joint is considered to be one of the most highly loaded joints in the body. The loads passing through it have been estimated to be about 3.3 times body weight when climbing up or down stairs, 7.6 times body weight with squatting, and up to 20 times or more body weight with jumping activities. Such high forces may result in loads that sometimes exceed the force capacity of structures in the area, leading to tissue damage and eventual patellofemoral pain.
The cause of PFPS is not entirely clear. It has been speculated that pain in this region may arise from improper tracking of the patella within the groove of the femur during certain activities. Some proposed mechanisms behind this poor tracking have been hypothesised to be a result of imbalances between the muscles on the inside and outside of the knee, improper timing of these muscles during contraction and an abnormal alignment of surrounding joints such as the hip, foot and ankle. The exact cause is most likely a combination of these and many other factors.
Proper diagnosis is critical to the potential treatment of PFPS. A multidisciplinary approach will help identify potential problems that may be leading to pain. Rehabilitation involves identification and modification of pain producing activities, techniques to reduce pain and inflammation of the joint, and treatment of the various contributing structures that can lead to PFPS such as weak core musculature, muscular imbalances around the hip and knee, and improper foot mechanics.Although the cause of PFPS remains uncertain, most patients do well with conservative treatment, and very few will require surgical intervention for this condition. Conservative management should include the following measures:
- Relative rest with temporary activity modification focusing on low-impact aerobic activity such as swimming, cycling or deep water running
- Quadriceps strengthening, stretching and retraining
- Stretching of lower limb muscles
- Proper training of core stabilisers
- Evaluation of footwear
- Patellar taping and/or bracing
As with most conditions, definitive treatment should be individualized and based upon physical examination. The health care professionals at Toronto SEMI are available to assist in the management of PFPS. Some of the services available include:
Sports medicine physicians to assist with accurate diagnosis, imaging, bracing and further orthopaedic referral and management as required
Chiropractic treatment to address any muscular or spinal imbalances
Podiatry to help in the treatment of causative factors such as altered foot alignment
Massage therapists to release tight musculature that contribute to PFPS
Physiotherapy to assist with patellar taping, strengthening, core stabilisation and quadriceps retraining
By identifying your specific needs and goals, we will develop a personalized treatment plan to help you reduce the symptoms associated with PFPS and assist you in returning to regular activity and sport.
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Crossley K, Cowan S, Bennell J, McConnell J. 2000 Patellar taping: is clinical success supported by scientific evidence. Manual Therapy 5(3): 142150.
McConnell J. 1986 The management of chondromalacia patellae: a long term solution. Australian Journal of Physiotherapy 32(4): 21523.
Baker V, Bennell K, Stillman B, Cowan SM, Crossley K. 2002 Abnormal knee joint position sense individuals with patellofemoral pain syndrome. Journal of Orthopaedic Research 20: 20814.