Dr. Anthony describes runner's knee (patello-femoral syndrome) and shares how it is treated.
I am asked a lot on runner’s knee. We do see a lot of runners, and we take care of a lot of runners. Runner’s knee is an inflammation underneath the kneecap. We also call runner’s knee patello-femoral syndrome. The patella is your kneecap and the femur is your thighbone which is right underneath the kneecap.
So runner’s knee or patello-femoral syndrome is a syndrome complex of inflammation and pain underneath the kneecap where it rubs on the femur or the thighbone. It comes about any time you change your running program. So, if you run two miles a day for four days a week and you bump it up to five miles a day, that’s a significant change, and depend upon your age, depend upon your biomechanics, that can cause inflammation underneath the kneecap and cause patello-femoral syndrome or pain in your knee, just underneath your kneecap.
Let’s say if you run three miles, three times a week and you are very consistent, no problems, and then you go on vacation for two weeks and don’t run. You come back and you restart three miles, three times a week; it’s very high chance that you are going to get a runner’s knee, especially as you get older because your body can’t accommodate as well.
So any change in your program, if you are used to running 30 miles a week, no problems, and now you changed shoes to a new shoe because after a year you decided you want new shoes, then that can cause it. If you are used to running straight and level, and now we start doing hills or trails, then that can cause it. So any significant change in your training program can cause patello-femoral syndrome or runner’s knee.
So how do we treat that? Well, it’s important to know that when you get that discomfort or that pain, then you are going to start to get atrophy of your quadriceps muscle because your body doesn’t want to have a strong muscle leading to an injured joint. The thing about the quadriceps muscle--and it’s called quadriceps because there’s four heads to it--and the quadriceps muscle, the VMO or the inside of the quadriceps atrophies first. So now we lose that vector force, and now the quadriceps muscle pulls the kneecap to the outside.
Well, if we look at the under surface of the kneecap, it has a bump on it, and that bump needs to ride in the groove of the femur, and if the kneecap is now pulled to the outside, now you have the bump of the kneecap riding on the bump of the femur, and that’s what causes the discomfort. This condition may not go away for years if you don’t take care of that.
How do we take care of it? Number one is that we want to decrease the aggravating activity to allow this to heal. You should be able to get back in a running so don’t get frustrated, but once we decrease the aggravating activity, allow it to calm down a little bit, now we want to ice it like most overuse injuries, and then after we have iced it, let it calm down a little bit. Now we want to strengthen up the VMO or the inside muscle of your quadriceps muscle, and the way we do that are things like quarter squats or terminal knee extensions or stationary cycle where your seat is all the way up or different activities where we are doing 30% of a squat, but not a full squat. If you do a full squat all the way down, then that’s putting too much pressure underneath your knee cap, and that will make it worse. But if we just go 30% or 25%, what we call a quarter squat, then it can strengthen up the VMO, bring the kneecap back into its alignment again, and allow the process to get better.
So after we ice it, we decrease the activity, and then we strengthen up the VMO with those easy activities. Now if you are an athlete that you have to get back in activity, we need to cross train a little bit. You need to do stationary bicycle or ellipse or swimming or something to allow this to heal while allowing your cardiovascular fitness to stay in shape and allowing your craziness to stay away, and then we start to gradually get back into running as we can, and the way we do that is start off slow and increase gradually.
So we start doing a walk-jog, easy walking and then easy jogging, and if then that doesn’t hurt, the next day you increase it to easy jog, and then we gradually increase as we can.
About Dr. Anthony, M.D.:
Dr. Anthony joined our practice in 1987 and is Board Certified in Family Practice and Sports Medicine. He is a Team Physician for the US Olympic Training Center, San Diego Christian College and Santa Fe Christian High School. He is an Assistant Clinical Professor at the University of California, San Diego School of Medicine, adjunct professor at San Diego State University, and the primary care physician for the Alvarado Spine Institute.