Knee Pain Management for Effective Results

Knee pain is the second most common complaint after low back pain when it comes to training.  Cranky knees can not only affect your clients’ training, but also their day-to-day.  You have an important role to play in helping your clients get out of knee pain.  Are you confident with your knee pain intervention?  If you’re hesitating at all, keep reading…I will explain how invaluable your role as a trainer is in the management of knee pain.

Etiology of knee pain

Trainees often develop knee pain as a result of repetitive loading of the patellar tendon, particularly in the form of repetitive energy storage and release.  High frequency and/or volume of Olympic lifts, squats, lunges, and their variations, as well as running and jumping activities, can surpass the patellofemoral tendon’s capacity to recover.

Other factors that can contribute to anterior knee pain are:

-unaccustomed physical activity

-change in volume or frequency of training

-excessive repetition of a particular movement or skill

-other injury that may result in a change in the way the individual is moving

-insufficient recovery between sessions or specific movements that overload the tendon

If you are working with a client who has recently developed knee pain associated with increased knee flexion (or loading on a flexed knee), pain just above the patella or pain at the proximal aspect of the patella, it will be important initially to avoid pain-provoking positions.  However, it is equally important to avoid excessively under-loading the tendon, as the removal of load altogether and the resultant lack of mechanical stimulus decreases the strength of the tendon and can even cause changes in tendon structure.

Using a case-by-case approach, managing the offending load on the tendon may vary from allowing a few days between high tendon loads to removing these altogether.  Generally, tendon loading without energy storage and release is well-tolerated, so defaulting to these types of exercises avoids under loading tissues.

Load management for knee pain

Tendinopathy is an umbrella term that indicates a non-rupture injury of the tendon that is exacerbated by mechanical loading.

Recent studies have shown that compression may play a role in tendinopathy.  Specifically, the combination of compressive and tensile loads on the tendon can be particularly damaging.  As such, rehab interventions aimed at managing load should focus on decreasing both tensile and compressive loads, while avoiding eliminating them altogether.

Essentially, rehab for tendinopathy is finding a balance on the protect vs expose spectrum.  We must at once protect the tendon from offending activities that will surpass its tolerance, while continuing to load it sufficiently to maintain mechanical stimulus.

Avoid stretching

When soft-tissue limitations are thought to contribute to excessive tension on the tendon, people have typically been instructed to stretch as part of the treatment for knee pain.  However, most stretches for the quadriceps result in a compressive load on the patellofemoral tendon and should actually be avoided (especially if the client has pain just above the patella).  If tension in the quadriceps muscle needs to be addressed, it is preferable to default to other soft-tissue mobilization strategies such as foam rolling, self-massage, IASTM, etc. at the bulk of the muscle while avoiding pressure over the tendon area.

Limit knee flexion

“The joint that travels the most gets the most amount of stimulus.”

The greater the moment arm at the knee for any particular exercise, the greater the tension and compressive load on the patellofemoral tendon.  As such, an important part of managing knee pain while maintaining sufficient load is to preferentially select exercises that have a lesser moment arm at the knee.  Shifting to more hip dominant exercise is an excellent alternative to keep your clients moving and keep them strong as they navigate through their rehab process.

Motor adaptation to pain

Clinically, the outcomes of treatment of tendinopathy vary—there is currently no single best treatment that has proved to be most effective.  What we do know is that persistent knee pain may lead to altered control of muscle recruitment and the consequent tendon load.  To put it simply, this means that there are neuromuscular adaptations associated with the persistent pain of tendinopathy which result in compensatory strategies to move outside of painful ranges of motion or decrease the load on the tendon at those ranges.

In the literature, this is referred to or described by the pain adaptation model, a model that proposes that changes in muscle activity serve to protect a region by limiting movement.  While it is generally accepted that pain alters movement, the underlying mechanisms of this behavior are not quite fully understood.  There are several proposed mechanisms by which pain changes the way we move that are effective at protecting from further injury:

• Recent studies have shown that adaptation to pain involves a redistribution of activity within and between muscles. New motor neurons are recruited during pain, which may be a strategy to preferentially activate muscle fibers with different angles and attachments.  This new net force direction would change the direction of contraction and the consequent load distribution on the painful structure.

• The redistribution of activity between muscles changes the mechanics of movement. While the gross outcome is maintained, the quality is affected, such as modified movement and stiffness.  In the long term, modified load, decreased movement and variability may have detrimental effects.

• The redistribution of activity within and between muscles and the altered mechanics of movement serve to protect the body from pain and/or further injury. This adaptation would also be expected with the threat of pain or injury, even in the absence of pain or injury, an important point to remember when dealing with individuals with unhealthy attitudes about pain.

The problem is that the motor control changes that occur with persistent knee pain may not spontaneously resolve or normalize following recovery.  Even with the disappearance of pain, there is a high rate of recurrence with tendinopathy.  It is possible that this is because current rehabilitation fails to restore corticospinal control of the muscle-tendon complex.  Essentially, people continue to move using protective strategies.

The role of externally paced exercise

Externally paced exercise is thought to address this corticospinal control component.  Tendon neuroplastic training is a concept of strength-based loading, an important stimulus for tendon and muscle, with strategies known to optimize neuroplasticity of the motor cortex and drive to the muscle.  Some studies have shown that both skilled training and metronome-paced resistance training, but not self-paced resistance training, increase excitability and release inhibition in the trained limb.

The concept is simple.  Instead of a self-paced exercise tempo, tempo is paced externally either visually or audibly.  I personally use an application called “Simple Metronome”.  It can be set to 60 rpm and you can add an audio and visual cue as well as a first beat accent to switch from the eccentric to the concentric phases.

Putting it all together

Here’s what integrating these concepts into a rehab plan might look like for someone struggling with anterior knee pain or patellofemoral tendinopathy:

Mobilization:

If soft tissue limitations need to be addressed, use self-myofascial release or any type of hands on release that does not involve stretching the quads via knee flexion to avoid compressive load on the tendon.  Go for 2 to 3 minutes of soft tissue work, or until you feel the area has released sufficiently.

Activation:

Letting the knee pass the toes is still an ultimate goal in patellofemoral rehab.  Unless it is very irritable, a shallow step-down exercise is ideal in the activation phase to progress towards that goal.  If it is too irritable, you can manipulate it to have the client step down slightly behind, making it more hip dominant, and progress from there.  It is also a good follow-up to the mobilization to reload the patellofemoral tendon.  The concept of external pacing can be integrated here.  I suggest slow and controlled repetitions with a 3-seconds up and 3-seconds down tempo.  Lower the non-support foot slowly towards the ground directly next to the support foot.  Keep all your weight on the support foot.

By the way, this is also a great exercise for hip stability.  Read more about it in this article: How to Build Resilient Hips

Integration:

In the Integration phase, as well as throughout the balance of the training regimen, we want to select exercises that have a lesser moment arm at the knee.  A great alternative is a box squat.  Again, an external pace can be utilized, with this as well as with other lower body exercises, such as shallow step ups.

Be sure to watch the video to learn how to perform these exercises.

Rehab is Training

As you can see, training plays an important role in tendinopathy rehab, perhaps an even more important role than manual therapy.  You will undoubtedly be faced with clients experiencing knee pain in your practice and having short and long-term strategies to help them through pain while keeping them in the gym is key.

Remember these key points: avoid stretching, remove offending load, progress towards loaded knee flexion while avoiding underloading by using more hip dominant exercises.

To optimize your intervention, use externally paced training to address motor adaptation to pain and help your clients avoid recurrence of knee pain.

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References:

Cook, J., & Purdam, C. (2011). Is compressive load a factor in the development of tendinopathy? British Journal of Sports Medicine, 46(3), 163-168. doi: 10.1136/bjsports-2011-090414

Cook, J., & Purdam, C. (2008). Is tendon pathology a continuum? A pathology model to explain the clinical presentation of load-induced tendinopathy. British Journal of Sports Medicine, 43(6), 409-416. doi: 10.1136/bjsm.2008.051193

Hodges, P. (2011). Pain and motor control: From the laboratory to rehabilitation. Journal of Electromyography and Kinesiology, 21(2), 220-228. doi: 10.1016/j.jelekin.2011.01.002

Hodges, P., & Tucker, K. (2011). Moving differently in pain: A new theory to explain the adaptation to pain. Pain, 152(Supplement), S90-S98. doi: 10.1016/j.pain.2010.10.020

Leung M, Rantalainen T, Teo WP, et al. Motor cortex excitability is not differentially modulated following skill and strength training. Neuroscience 2015;305:99–108.

Malliaras, P., Cook, J., Purdam, C., & Rio, E. (2015). Patellar Tendinopathy: Clinical Diagnosis, Load Management, and Advice for Challenging Case Presentations. Journal of Orthopaedic & Sports Physical Therapy, 45(11), 887-898. doi: 10.2519/jospt.2015.5987

Rio, E., Kidgell, D., Moseley, G., Gaida, J., Docking, S., Purdam, C., & Cook, J. (2015). Tendon neuroplastic training: changing the way we think about tendon rehabilitation: a narrative review. British Journal of Sports Medicine, 50(4), 209-215. doi: 10.1136/bjsports-2015-095215

Mai-Linh Dovan M.SC., CAT(C)
Certified Athletic Therapist
Founder of Rehab-U