Assignment 3
Alvin Li (23783780)
Kin 205
Dr. Carolyn McEwen
December 8th, 2023
Literature Review
Patellofemoral pain syndrome (PFPS) describes pain within the anterior region of the
patella that is caused from load-bearing activities that extend or flex the knee joint (Hamada et
al., 2017). It is a common condition that affects around a quarter of the population (Hamada et
al., 2017). There is no set diagnosis for PFPS, thus every study uses a different type of test to
diagnose PFPS (Moyano et al., 2012). It is common for studies to use quantitative surveys for
patients to self-assess their knee pain in addition to functionality tests of the knee (Hamada et al.,
2017). For example, a few studies use a Kujula questionnaire, a quantitative self-reported
questionnaire that measures knee pain and functionality out of a score of 100, with 100 being the
least amount of pain and the most functionality (Hamada et al., 2017). There are many factors
that may cause PFPS such as muscular imbalances, abnormal structural differences in the knee
joint, bad form, and simple overuse (Moyano et al., 2012). Although PFPS is common, there is
currently no agreed on ‘best’ intervention for treating it and thus many clinicians have different
methods for treating it (Østerås et al., 2013). With PFPS being so widespread, it is important that
a consensus is reached on the best methods to treat it as it would greatly improve the quality of
life and performance for those affected by PFPS (Earl & Hoch, 2010). Not only that, it would
also be more ethical in providing the best treatment for those suffering from PFPS since it would
be unethical for those with PFPS to receive subpar or even harmful intervention from a
professional (Stolt et al., 2017). The purpose of this research proposal is to discuss what is
currently known about PFPS and aim to uncover what the best type of treatment is for PFPS.
Through a randomized experimental trial done on participants aged 18-35 with PFPS that
were not caused by a direct injury, Hameda et al. (2017) quantitatively measured knee pain and
functionality throughout the study and found that PFPS decreased following the hip and knee
strengthening exercises. In a randomized experimental trial, Motealleh et al. (2019)
quantitatively found that knee pain was decreased following a period of strengthening the core
muscles in female patients with PFPS that had no history of direct injury in the knee. Combined,
these studies imply that accessory muscles that do not directly move the knee, such as the hip
and core, should also be strengthened in order to improve pelvis stability and reduce force
absorption in the patellofemoral joint and thus reducing PFPS. The amount of repetitions and
amount of weight used to train may also affect the symptoms of PFPS (Agergaard et al., 2021;
Østerås et al. 2013). Agergaard et al. (2021) quantitatively found that different loads of weight
lead to negligible differences in reducing PFPS through a randomized experimental trial
involving adult male participants with PFPS and no history of acute knee injuries. However, high
dosage combined with high repetitions of strengthening exercise does seem to lead to lower
levels of PFPS according to a randomized quantitative experimental trial done by Østerås et al.
(2013). These findings imply that exercises administered to reduce PFPS should focus on higher
dosage and higher repetitions as opposed to higher weight used (Agergaard et al., 2021; Østerås
et al., 2013). Proper running gait form does seem to reduce PFPS as found in a randomized
experimental trial that quantitatively found that knee pain was reduced post intervention by
converting heel-strike runners into fore-foot strike runners (Roper et al., 2016). All together, it is
known that strengthening exercises involving the knee and certain accessory muscles are able to
reduce PFPS but underlying issues such as gait form should also be addressed.
One of the biggest limitations in all of the aforementioned studies is a substantial
followup on the patients. Although patients in most of the interventions reduced their knee pain
immediately following the study, there is no study done following up a year or multiple years
after the study. Therefore, it is hard to conclude the long term effects of these interventions and
weigh the actual value of it. Even though running form was found to influence PFPS, other
motions involving the legs should also be examined to see their effects on PFPS (Roper et al.,
2016). These motions should include common movements such as jumping and landing that
could cause/increase PFPS (Wilson & Davis, 2009). In addition, most interventions only last a
couple months so it is unknown if a longer intervention time would lead to an even bigger
decrease in PFPS (Hamada et al., 2017). Finally, all the aforementioned trials compare only one
intervention at a time and do not consider the effects that one intervention may have on another.
In other words, it is unknown what combination of interventions may be best for treating PFPS
or if only one intervention should be used at a time.
The next step in research would be to find out if the symptoms of PFPS come back after
the halt of treatment, and if so, find out how long after treatment does pain come back. The long
term effects of treatments are currently unknown and it is important to know because if certain
interventions have knee pain come back immediately after the halt of treatment it would mean
that the treatment is ineffective in treating PFPS (Motealleh et al., 2019). Another important step
would be to find the optimal combination of interventions for the best plan. For example, should
an intervention program consist of relearning form, followed by stretching, and then followed by
strengthening or should it be done all at once? Ultimately, pursuing these avenues will increase
the efficacy of treatments while also preventing unintentional malpractice by finding out what
program is the most efficient in reducing PFPS.
References
https://journals.sagepub.com/doi/full/10.1177/0363546510379967#bibr17-0363546510379967
https://journals.sagepub.com/doi/full/10.1177/0969733017700237
https://thescholarship.ecu.edu/bitstream/handle/10342/4278/36641330.pdf;jsessionid=070812D5
479CEF58AD2C7EE2508A895B?sequence=1