Running into Relief: Tackling Runner's Knee

"Runner's knee" is a common term used to refer to patellofemoral pain syndrome (PFPS) which is a widespread issue, impacting as many as 1 in 4 adults according to Dey et al. (2016). It manifests as a diffuse ache in the front of the knee, worsened by repetitive movements and activities stressing the patellofemoral joint, such as running, squatting, prolonged sitting, and going up or down stairs, as noted by Witvrouw et al. (2014). This condition brings significant suffering and negative emotional effects, as highlighted by Smith et al. (2018). PFP doesn't discriminate, affecting various groups including the general population, amateur and professional athletes, and military recruits (Dorotka et al., 2003). Females tend to experience it more frequently than males, with reported annual prevalence rates of 29.2% and 15.5% respectively in the general population (Dey et al., 2016). However, the overall prevalence might be higher than the estimated 23% in the general population by Smith et al. (2018) since many PFP sufferers steer clear of activities that worsen their symptoms (Rathleff, Rasmussen, and Olesen, 2012).

Injury development theory

Several theories have been proposed to explain the development of pain in individuals with patellofemoral pain (PFP). However, none of these theories are currently considered definitive or universally applicable to all PFP cases, as noted by Lack et al. (2018). Anatomical irregularities in the trochlea and patella, such as patella alta, have been linked to patellar maltracking (Frosch and Schmeling, 2016; Pal et al., 2013). Regardless of the root cause, patellar maltracking results in reduced contact area between the patella and trochlear groove, thereby increasing stress on the joint and causing pain due to heightened compressive forces on the patellofemoral joint (Petersen et al., 2014). Another hypothesis suggests that inflammation and degeneration in structures like Hoffa’s fat pad and synovium, coupled with increased bone metabolic activity, disrupt tissue balance and contribute to pain (Dye, 2005). Additionally, some researchers propose that chronic PFP includes a significant neuropathic element (Jensen, Kvale, and Baerheim, 2008).In individuals with patellofemoral pain (PFP), laboratory measurements have revealed certain abnormalities compared to healthy controls. These include delayed activation of the vastus medialis relative to the vastus lateralis during functional activities, a factor contributing to lateral tracking of the patella (Cavazzuti et al., 2010). Other observed differences involve changes in ground reaction forces, indicating alterations in ankle and foot movements (Levinger and Gilleard, 2007), as well as decreased strength in the quadriceps, hip abductors, and hip external rotators (Rathleff et al., 2014).

Conservative treatment

Exercise therapy stands as the cornerstone of conservative management for patellofemoral pain (PFP) according to Neal et al. (2019b). Substantial evidence supports that a blend of strengthening exercises for both proximal and knee muscles leads to reduced pain scores in individuals with PFP, with a notable decrease of -3.3 in 1 to 10 pain intensity scores, even when significant measurable strength gains are lacking (Nascimento et al., 2017). It's crucial to pinpoint specific biomechanical deficiencies to tailor a personalized rehabilitation regimen that optimizes these improvements in pain and functionality (Lack et al., 2018). A standardized rehabilitation plan focusing solely on knee and proximal muscle strengthening overlooks the diverse risk factors associated with PFP (Lack et al., 2018). Addressing specific strength weaknesses typically begins with open kinetic chain exercises but progresses to closed kinetic chain exercises to mimic functional movements as the individual advances in their rehabilitation journey (Barton et al., 2015).

Incorporating stretching exercises for tight muscle groups, particularly the quadriceps and ankle dorsiflexors, where tightness is identified during assessment, is recommended (Barton et al., 2015; Rabin et al., 2014). Both dynamic and static stretching have shown to improve pain scores significantly (p<0.01) when performed by individuals with hamstring inflexibility (Lee et al., 2020). During rehabilitation, if certain exercises provoke pain, they may need to be avoided initially, with a greater emphasis on isometric strengthening before progressing to dynamic tasks. Utilizing biofeedback tools like video recording or mirrors to provide visual feedback to the individual is also advised to address abnormal kinematics (Barton et al., 2015).

Adjuncts to rehabilitation may include short-term use of non-steroidal anti-inflammatory drugs (NSAIDs) (Dixit et al.) and transcutaneous electrical nerve stimulation (TENS) (Can et al., 2003) to alleviate pain. TENS has also demonstrated improvements in function, defined as knee range of motion and vertical jump height (Valenza et al., 2016). Focusing on the aforementioned rehabilitation methods has been proven effective in enhancing function and alleviating pain in individuals with PFP.

#Biokinetics # Injuryrehabilitation #Running #Runninginjuries #Injuryrehabilitation #Exercise #Lifethroughmovement