knee pain, runner
Health

New research into patellofemoral pain means hope for athletes

knee pain, runnerWith any glimpse of a warm day in the winter, or the first sunny day that arrives in spring, there seems to be an unusually large number of people who head out for a run. For many though, this activity doesn’t last long.  Shortly after those first few runs, knee pain ensues.

Why, sport and the body
Patellofemoral pain impacts a lot of athletes. And if not treated it can possibly lead to structural damage in the knee.

One of the most common causes of knee pain in runners is patellofemoral pain. Affecting more than just runners, however, it is common in athletes who inflict regular, repetitive impact on the knee joint, have rapid stop-and-start motion, or in athletes who have a high intensity increase in load on the knee joint over a short period of time.

Formally known as Patellofemoral Pain (PFP), this condition presents when the aggravation appears in and around the joint between the patella (knee cap) and the femur. It is differentiated from pain caused by other conditions, such as Iliotibial Band Syndrome, in that the pain is localized to the knee cap, not on either side of the knee. Other symptoms include increases in pain when loading or during impact (i.e. running, squatting, descending stairs), and in prolonged periods of flexion, such as kneeling or sitting. It is a condition that is based on a diagnosis of exclusion, whereby practitioners typically seek to rule out all other possible diagnoses before landing on PFP.

A common condition, researchers and clinicians have been aware of its pervasiveness amongst the athletic population. Given the complexity of the knee joint, however, until recently clinicians did not have a consistent means of classifying the pain and its cause, nor the ability to provide consistent, research-backed treatment solutions. In addition, much of the research that has been done has not been collated together or synthesized into regulated guidelines. 

To address this, a group of practitioners and researchers from around the world published the Patellofemoral Pain Clinical Practice Guidelines. One of the authors of the publication, Christian Barton, explains that the aim of the publication was to adopt international insight into the subject matter and bring the content into a succinct set of parameters for practitioners to use. It has also allowed for consistency across academic institutions and in student training. Incoming practitioners can be educated and be up to date on the newest treatment recommendations, and be able to offer the best options for patients, complete with correct, individualized back-to-activity plans.

Based on the recently released guidelines, PFP is classified under four categories, according to its presenting causes:

  1. Overuse/Overload without other impairment: When the patient presents with recent history indicative of an increase in the magnitude or frequency of load on the knee joint, which is more than it can handle with adequate recovery. This is a common diagnosis for a runner, caused by increasing mileage or intensity too quickly, without adequate rest.
  2. Muscle performance deficits: This is a classification offered to those who have deficits in performance in muscles of the lower extremities, such as hips and quadriceps.
  3. Movement coordination deficits: A patient presenting with internal rotation of the knees (known as genu valgus), and thereby poor ability to control movement during tasks, such as running or squatting, may be classified with this as the cause. For runners, this can be a case of poor knee alignment or knock knees during activity.
  4. Mobility Impairments: This classification accounts for higher-than-normal foot mobility or flexibility, and deficits in other structures such as the hamstrings, quadriceps, calves or ITB.

Using these guidelines, it is possible to deduct a series of potential root causes of patellofemoral pain: foot mobility issues; weakness in the hamstrings, quadriceps, calves or hips; ineffective knee alignment; or simply “too much, too soon” when it comes to running volume and increases in intensity.

The guidelines are comprehensive in the content they offer for diagnosis and causes, but as Barton notes, these guidelines are not necessarily targeted for the public. Patients should be consulting a professional in assisting them to work through an individually recommended diagnosis and rehabilitation plan for their specific presentation of symptoms.

As with any condition, as Barton underscores, individuality is paramount. The guidelines do not propose to become a one-size-fits-all prescription, but rather a set of parameters around which practitioners and athletes can work to be funneled toward the treatment option that is most likely to be successful for them.

One recent study, for example, acknowledged that PFP sufferers often present with atypical movement in the frontal plane of the hips and pelvis. This could be maladaptive pelvic tilt, for instance, which is affecting the alignment down the chain and leading to pain in the knees. In this study, researchers concluded that the use of a protocol to increase step rate was effective for runners who were impacted by PFP from this cause. Increasing step rate or undergoing gait retraining, however, does not act as the single solution for PFP sufferers. The guidelines seek to support studies such as this one, giving patients and clinicians good launching points to craft an appropriate return to sport plan.

In many cases, one of the first of these launching points is an evaluation of the training history to assess the need for load management. Many athletes simply need to avoid a case of “too much too soon.”  In developing the guidelines, experts reviewed nearly 4,500 scientific articles seeking to simplify and systematize treatment across all athletes and modalities. In doing so, the key take-aways indicate:

  •     treatment plans need to be individualized
  •     electrophysical agents and long-term passive treatments are not beneficial
  •     a combination of education, and hip and knee exercises together offer the best long-term outcomes for most individuals

For many athletes, however, it’s not about treatment, but rather preventing the issue in the first place. Brodie Sharpe, a physiotherapist and the host of the Everyday Running Legends podcast, explains: “Patellofemoral pain was once believed to be due to ‘mal-tracking,’ of the patella.” No longer, however, is it necessarily caused by poor mechanics or poor technique, and as researcher Kay Crossley has recently published, it also may not be simply the VMO that needs attention. Instead, as the guidelines conclude, there are many possible causes and the mode of treatment for each will vary with symptoms and the athlete. Likewise, Sharpe explains that there may be a need for short-term treatment options, such as taping, which will help the athlete get back to sport sooner, while long-term rehabilitation work is occurring.

Barton concurs that load management is still one of the most accessible means of treatment and prevention, and this can be easily managed by the affected individual. ““The absolute key to preventing and managing PFP is being sensible of how much exercise you do. Be consistent with your exercise routine and avoid the ‘boom and bust’ mentality.”  From a clinician perspective, Barton also highlights that it is crucial for practitioners to look at the whole picture and be aware of the biopsychosocial model of pain: if a runner, for example has experienced PFP before and not seen relief, the brain may elicit pain due to a perceived threat, upon attempting to return to running. In cases like this, it is important to offer adequate education to build confidence in the runner that the structure is sound, and to build up a running program slowly to reduce regression.

If you’ve experienced it, you know the pain of PFP can be severe and debilitating, and make it seem like a serious condition that will never go away. These new guidelines, however, seek to offer some scientifically sound solutions for prevention, cause and treatment, and have the potential, moving forward, to dramatically change the landscape of what PFP means for athletes.

Laura Peill, a Canadian living in Australia, is an avid long-distance runner, nutritionist and Pilates instructor, who spends her time teaching and writing about movement. She uses these modalities to help individuals shift their mindset around health, and overcome hurdles holding them back from their own success.

Editor’s note: For the 2019-2020 academic year, the Global Sport Institute’s research theme will be “Sport and the body.” The Institute will conduct and fund research and host events that will explore a myriad of topics related to the body.