Why strengthening your glutes isn't enough if you have patellofemoral pain
Two months ago, I started working with a 36-year-old runner dealing with patellofemoral pain. It started rather abruptly following a 15-mile long run. Her typical routine involved running 9 to 10 miles as her farthest distance of the week, but while engaged in conversation with her friend, she tacked on an additional 6 miles. In evaluating her knee, we saw that when she ran and squatted, it immediately collapsed. This meant it adducted and internally rotated. This is the knock-knee presentation we often see in runners with patellofemoral pain.
Cue the clamshells, monster walks, bridges. Search the internet. These are the key exercises needed to rid yourself of patellofemoral pain.
However, when we tested her strength, she was rock solid in all of her glute muscles. When we looked at her hip flexors and adductors, she was quite weak. Our treatment looked a little different than what is typically given for runners with knee pain. The result? She got better.
If you've tried glute strengthening for two to four weeks and your knee pain isn't improving, a pivot to strengthening your hip flexors and adductors leads to potential gains.
The knee is a simple joint. It is a hinge. It bends and straightens the thigh bone. However, the thigh bone also attaches to the hip, which is a tri-planar joint. This means not only does it bend and straighten, but it can move side to side and rotate. People with knee pain demonstrate excessive femoral adduction and internal rotation. These motions can lead to altered forces at the knee when in abundance or intensity.
By addressing the excessive hip internal rotation and adduction via strengthening the gluteal muscles, the forces stressing out the knee cap will be resolved and knee pain will alleviate. So Surely, runners with knee pain who strengthen the muscles that move the knee into adduction and internal rotation would worsen their pain and running, right?
A group of researchers looked this theory. Almeida et al. in 2021 sought to see if there was a difference in working on the hip adductors, flexors, and internal rotators compared to the hip abductors, extensors, and external rotators (aka the glutes) in affecting knee pain and function.
Guess what they found? There was no difference in the two groups; both groups had significant improvement in pain and function. Of note, this was a study that focused on females, 52 females with patellofemoral pain.
They threw out the bridges, clamshells, and monster walks and instead did straight leg raises, banded hip flexions, side lying adductions, and Copenhagens. This result came as a shock to the PT community because of the long-standing belief, rooted in evidence but also dogmatically handed down to generations of physical therapists.
So how did this happen?
- First, general loading and cumulative strength and conditioning help the knee. We know that often a tissue that becomes overused is then sensitive to movement. That sensitivity leads to a load intolerance. The authors hypothesized that improving load tolerance through a variety of movements and exercises stimulated a healing effect.
- Second, the hip flexors (aka the iliopsoas) helped to provide stability at the hip and femur. This had a ripple effect on stabilizing the patellofemoral joint*;* therefore, the iliopsoas potentially assisted in controlling the thigh bone and thus the patella in functional movements.
- Lastly, there is potentially a kinetic biomechanical change to the area. To get a bit nerdy, when we think of biomechanics, we divide it into two areas. One is kinematic, and the other is kinetic. Kinematic biomechanics looks at the things you can see: the positions and ranges of movement of the body. Here, this would be the aforementioned side-to-side or rotation movements at the knee. Whereas kinetic biomechanics looks at the forces acting within or on muscles and joints*. These are the things we cannot see. The authors' third hypothesis is that through strengthening the hip flexors, adductors, and internal rotators, it improves the kinetics of the muscles and joints.
So how do you know what treatment is right for you? Well, first, you can just hedge your bets and do all of it, a shotgun approach. This would be more time-consuming, and you likely have many responsibilities in your life that extend beyond running. What I would do is test all the muscles:
- Side planks with the top leg lifted and single left bridges to check the glute strength
- Adductor planks along with single-leg front planks for the groin and hip flexors
I generally like to hold all these for 30 seconds and see if there is a breakdown or a tap out of the muscles. This is a sign that coordination or capacity is reduced and therefore worth addressing, as not only will it help the mechanics at the knee, it will also help promote more load tolerance.
Of note, if you've been dealing with knee pain for more than four weeks, then you should be evaluated by a running-focused physical therapist or a physician to help get you into the best treatment possible.
The takeaway here is: don't guess, get assessed, and know that you have options. When it comes to patellofemoral pain, there is not a one-size-fits-all treatment. It is dialing it in to what you need the most, checking constantly for therapeutic benefits, and loading your tissues so they become more resilient.
We help runners in DC dealing with knee pain, contact us today, and let's get the ball rolling to logging more miles!