Runner’s Knee: Part II
Runner’s Knee: Part 2
The last blog was an introduction to runner’s knee, discussing symptoms and causes. Today’s post will continue the conversation, focusing on how to treat this common injury. The previous post also included a list of factors identified in the literature to be associated with runner’s knee, listed again below.
· Training errors/overuse
· Weakness at the quadriceps, hip, or trunk musculature
· Muscle tightness or shortness at the quadriceps, calves, or hamstrings; IT band thickening may also be present
· Biomechanics or movement patterns during walking, running, stairs, squatting
· Anatomy/joint alignment
Although many of these factors have been identified in the research to be associated with runner’s knee, they aren’t necessarily universal to everyone who has runner’s knee. For this reason, it is important to take an individualized approach focusing on the primary issues unique to each person’s case. During rehabilitation, the factors that we have influence over include (1) activity level, (2) strength, (3) flexibility/mobility, and (4) movement patterns. Treatment primarily focuses on improving these areas. We will highlight what weaknesses or deficits may be present, why they are significant, and how to address them.
1. Activity Modification
o This is a simple concept with some nuance to it. Runner’s knee is typically related to overuse or overloading. Therefore, treatment is initially about off-loading the patellofemoral joint through various strategies to allow symptoms to calm down. This doesn’t mean complete rest.
o If you can’t get through your daily routine e.g. walking short distances, getting up from a chair, and going up/down stairs, then you will likely benefit from replacing running or other aggravating activities with something else that is better tolerated for a short amount of time.
o Training errors are a huge and under-appreciated cause of overuse injuries. Your training schedule needs to be intentionally managed in order to have a successful rehab and to improve your chance of staying injury free in the future.
2. Strengthening
o Quadriceps
§ Quadriceps weakness has been shown to be associated with the development of runner’s knee. The quad muscles are a large muscle group that assists with shock absorption. Think of your knee as a spring that bends to absorb shock – the quads (along with the hamstrings and calves) control that bending. If the quads are weak, the knee likely won’t bend as much and more force will be dissipated across the patellofemoral joint, especially in the lateral direction.
§ The quad muscles will also become inhibited/weak when there is swelling present at the knee. For this reason, controlling any knee swelling is important in order to improve quad strength.
§ Exercises: SLR, mini squat
o Hips
§ Individuals who have patellofemoral pain also have strength deficits at the hip – particularly the gluteal muscles, although no cause and effect relationship has been identified. It is possible that knee pain has an inhibitory effect on the hip muscles, with resultant weakness developing as a consequence of runner’s knee. Regardless, it is key to restore strength to the hip during the rehab process. The hip muscles help control the position of your femur (thigh) which in turn impacts the positioning and loads going through your knee joint.
§ Exercises – clams, bridges, side-steps
o Trunk
§ Individuals with runner’s knee have been reported to have reduced trunk or ‘core’ strength.Greater trunk strength has also been shown to be correlated with improved control of the knee during weight-bearing and greater self-reported function in individuals with runner’s knee. In other words, more core strength equals better movement and better function.
§ Exercises: dead-bug, bird-dog, side planks
o Treatment– Implementing a strengthening program takes time and consistency. It will take 4-6 weeks to see improved muscle fiber strength, but you can see shorter term improvement via increased neural drive to muscles in much less time. Although pain is inevitable during the rehab process, strengthening exercises should not cause excessive irritation to the knee and may need to be modified in intensity or duration to find the right level of challenge. Exercises listed are foundational, and will need to be progressed. Depending on your starting strength and the activity you are trying to return to, you may achieve adequate strength after 6 weeks or it could take several months.
3. Flexibility/Mobility
o Quadriceps
§ Tightness of the quadriceps can increase joint reaction forces through the patellofemoral joint. Several studies report that individuals with runner’s knee exhibit tightness of the quadriceps muscles compared with those without symptoms. A shortened quadriceps muscle has also been shown to be a predictor of the development of runner’s knee.
o Hamstrings
§ Shorter hamstring length was associated with increased joint reaction forces through the patellofemoral joint during a squatting task. However, hamstring tightness has not been identified to be a predictor of runner’s knee development.
o Iliotibial (IT) Band
§ Individuals with runner’s knee pain have been shown to have a tighter and thicker IT band compared to individuals without symptoms. There are some studies that have found iliotibial band tension can impact patellar alignment. It is important to note that this is an association, as no cause and effect relationship has been identified. IT band tightness and thickening could be an adaptation versus cause of lateral tilt/translation of the patella.
o Calves
§ Individuals with runner’s knee may exhibit calf tightness, although this is not a universal finding. Calf tightness can also contribute to mobility deficits at the ankle.
o Foot and Ankle Mobility
§ Limited ankle dorsiflexion (ability to flex toes towards your shin) is associated with diminished movement quality at the knee (knee valgus) while descending stairs.
o Treatment –Soft tissue mobilization provides good short-term symptom reduction. There are many options for soft tissue mobilization including massage, foam-rolling, dry-needling, instrument-assisted soft tissue mobilization and cupping. Dynamic stretching can be included at the beginning of your exercise routine and static stretching can be included towards the end of your exercise routine. These treatments should not be done in isolation, but as an adjunct to strengthening exercises as a ‘tight’ feeling muscle is often a weak muscle, and everything will ‘feel tight’ again unless these mobility type exercises are paired with strengthening.
§ Exercises:foam-rolling, 1-2 minutes at each area – quads, hamstrings, gluts, IT band, dynamic and static stretching for quads, hamstrings, calves, static stretches should be held for 30 seconds, ankle dorsiflexion mobility drills.
4. Biomechanics or Movement Patterns
o When looking at movement patterns or biomechanics – there isn’t necessarily one correct or perfect way to move, we can think more in terms of certain strategies will load more through the knee versus more through other areas. Along these lines, changing movement patterns can assist with the goal of off-loading the knee to allow symptoms to calm down. Additionally, changing movement patterns can also help with the goals of strengthening and improving mobility. As you move differently, you may begin using different muscles groups more and moving through different areas.
o The movements that are evaluated will be the movements that are important to to you and your daily activities – standing, walking, squatting, running, etc. Some factors that we may look for that have been associated with runner’s knee include:
§ Hip/thigh positioning
· Excessive internal rotation
· Excessive adduction
§ Knee positioning
· Hyperextension or locking
· Excessive external rotation of the shin bone
· Decreased flexion of the knee
§ Trunk position
· Excessive lean of the trunk towards the involved side
· Excessive rotation of the trunk towards the involved side
§ Ankle/foot movement
· Decreased ankle dorsiflexion
· Arch collapse during weightbearing (static pronated foot posture is not linked to runner’s knee, but dynamic foot function is)
o If arch collapse is occurring, orthotics may be worth trying for short term pain relief. The foot and leg muscles should be strengthened to improve foot function and strength of the arch.
o Treatment:Although some movement patterns improve just through performing strengthening exercises, sometimes you already have the strength, and it’s more about creating some awareness around the movement so that you can change habits. This can be done through various types of cueing and drills. Here are some examples of what we may address with each movement – these are generalized, and modifications may be required based on each individual.
§ Sitting down and standing up: lean your hips further back and squeeze your glutes, keep your knees tracking outside of your big toes
§ Standing: center your weight in your midfoot versus in the heel or the toes, keep your glutes and abdominals active, don’t lock out or hyperextend the knees
§ Walking: make sure you aren’t hyperextending your knees, strike the ground with a heel to toe strike pattern, utilize your glutes and calves for push off
§ Running: land with your foot closer to your body and center of mass in order to decrease loads through the knee, this can be accomplished by increasing your cadence (how many steps you take per minute)
Other treatments including taping and orthotics can help provide short term pain relief, particularly when combined with an exercise program. Taping provides increased sensory feedback to the brain which may help adjust your movement patterns or decrease perception of pain. Orthotics provide more of a mechanical support to address issues with dynamic foot function, like arch collapse while walking.
The good news is there is excellent support in the research for the benefits of exercise on runner’s knee. Exercise therapy has been found to improve pain in the short, medium and long terms, and function in the medium and long terms.
If you think you are suffering from runner’s knee, call 312-643-1555, book online, or email [email protected] to schedule a physical therapy evaluation. Like us on Facebook or follow us on Instagram @dynamicptchicago for more information on common musculoskeletal injuries and how to treat them.
1. Powers CM et al. Evidence-based framework for a pathomechanical model of patellofemoral pain: 2017 patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester, UK: part 3. Br J Sports Med. 2017 Dec;51(24):1713-1723. doi: 10.1136/bjsports-2017-098717. Epub 2017 Nov.
2. Collins NJ. 2018 Consensus statement on exercise therapy and physical interventions (orthoses, taping and manual therapy) to treat patellofemoral pain: recommendations from the 5th International Patellofemoral Pain Research Retreat, Gold Coast, Australia, 2017. Br J Sports Med. 2018 Sep;52(18):1170-1178. doi: 10.1136/bjsports-2018-099397. Epub 2018 Jun 20.
