Pain behind the knee when crouching or going downstairs could be from the little popliteus or plantaris muscles. More likely the pop. I had a personal experience with this muscle backpacking in New Hampshire. My son and I hiked down the mountain after being in the sky for a few days and when reaching flat ground I couldn’t walk to my car! The back of my knee was in a painful spasm.
The major complaint of patients with knee pain caused by Trigger Points in the popliteus is pain when crouching or walking, especially downstairs or downhill. Often overlooked in knee pain complaints, I pay attention to these deep little muscles in my Neuromuscular Therapy center near Boston.
The popliteus is a triangular flat thin muscle behind and below your knee. It’s tendon attaches at the outside of your knee on the thigh bone (femur) and spreads across the space between the two bones of the lower leg to the bigger of the two (tibia) in a wide attachment along the ridge of bone below the inner crease in your knee.
The popliteus has an important function of preventing your thigh bone from sliding off the lower leg bones when your knees are bent, like when you’re going downstairs, crouching, skiing or hiking downhill, or walking in high heels!
The action of the popliteus when it contracts is twofold. 1) It rotates your lower leg at the knee like when you do a twisting turn to change direction in sports. Any action that can tear the cruciate ligament can also injure the popliteus. 2) The second action is to unlock your knee. It stays active through any weight-bearing bent-knee activity.
The plantaris is a delicate little muscle that crosses the space behind your knee. It doesn’t do much by itself, but it helps invert your foot and point your toe. It’s Trigger Point is behind the knee and down into the calf.
Both pop and plant muscles can be aggravated by flat feet or from walking on a slanted surface. So wearing an arch support and walking the beach in both directions are good ideas! Remember not to overload them during a flare-up.
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Hi - I have been having an issue for about a year that prevents me from doing the elliptical machine. After about 10 minutes, the back of my knee contracts and i cannot straighten my leg. It is painful and feels like a tendon is about to tear. The only way I can get it to release is to use a ball on the back of my hamstring and foam roll from mid thigh down to mid calf. Until today, i thought it was my hamstring cramping, but now i think it is this muscle freaking out.
It also happens when i use machines like the step mill (an escalator-type step machine) and when i walk on the treadmill uphill. I’m having a lot of trouble getting a cardio routine going because of this… I used to do 45-60 minutes cardio 4-5 days a week, and now i’m lucky if I can get 25-30 in on a treadmill. It is driving me crazy.
I have tried a lot of different kinds of stretches, but nothing seems to work. Do you have suggestions for how I can treat this? I’m in Michigan, so Boston is a bit far for me to come for an office visit… :)
Thanks so much… I really need some suggestions!
Hi Holly, Thanks for your question! Could be the popliteus, but sounds more like gastroc to me because of your comment that it reacted going uphill. Popliteus doesn’t like going downhill. Just treated an athlete yesterday with the same complaint. You can test it by pressing with a ball just below the crease of your knee, squeezing it with your thigh. Don’t hold for longer than 20 seconds because there are nerves and blood vessels there. The popliteus hurts when you crouch. In addition to the several entries on the muscles that can cause knee pain, I posted one yesterday on other sources and one today on stretches for all of the muscles. The stretch for the popliteus should hurt when you do it. If it doesn’t, try the other stretches and feel for tension and pain and check for range of motion. Let me know what you find. Christina
Hi,
I’ve had a similar knee problem for about one year. Except with one or two variations. When I sit in a chair and try to scoot forward with my feet planted on the ground my knee gives me some pain, about a 4 on a scale of 10. I went to the doc today and she said it was a joint problem, but I really think its muscular. I am in the military and really have no choice of doctor. I really do not want to take the anti inflamitory I was prescribed unless that is what I really need. I did not get any advice on prevention or any alternative to the med. Do you have any advice?
Thanks for the great article on the popliteus. I am not a bowler, but went to a bowling party and played 3 games without problems, then, when changing into my street shoes the spasm occurred. I could not believe the pain. No popping, swelling, or point tenderness. The pain persisted, even with anti-inflammatory meds. I now have a neoprene sleeve which helps, and I am able to walk without pain 2 days later. I now know I need to strengthen the whole knee joint, and will do so in the coming months. I am a regular biker and hiker, yogi, and gym person, and am so surprised that this occurred. But it is my “Achilles”!! Is there a special move to strengthen the pop?
I’ve never had problems before, but a week ago I was playing paintball on a rather steep hill. Out of the blue, while I was crouched, I felt a pop behind my left knee that felt like a charly hourse and I had to straighten my leg out. I walked it off, but it happened two more times that day. I was left with a soreness behind my knee. Today, while I was crouched down painting a doorway it happened again. Do you think this is my issue and if so, what are my options? I’d prefer not to go to a docter, but if it’s something major, i’d rather not wait.
Thanks,
James
Hi Sergio, If I understand you correctly, I would suspect the quadriceps as the problem. They cross the knee joint and when they tighten up (as they do when you start to stand up which is the muscle action when you scoot forward) they can compress the joint and cause pain. The quads also have Trigger Points that refer into the knee. If the pain is behind your knee, it could be the hamstrings or the popliteus/plantaris. Pain in the sides of the knee are from the quads or the inner thigh muscles (adductor magnus, sartorius, gracilis).The outside of the knee can also be from the popliteus tendon or colateral ligaments. The treatment would be pressure on the muscles using NMT protocol and stretching to reduce tension and release Trigger Points. The way to know if the muscles are involved is to be very specific in your self-applied pressure. The places that hurt indicate muscle dysfunction. Let me know if that helps.
Hi Lake, The popliteus is a hard one to strengthen and to treat because it functions in subtle ways and is deep in the leg. Downhill walking and hiking are when it gets used a lot, so that would be the best strengthener. Be careful about going beyond 90 degree flexion. Stretching all the muscles that cross the knee would be a good course of therapy. In yoga you have stretches you can use, but in your case, hold the stretches for only two seconds and repeat 10 times instead of holding the stretch. If there are Trigger Points, holding a stretch can irritate them because of the activity of the stretch reflex which under these conditions can activate the response and contract the muscle you are trying to stretch. It sounds as if your muscles are getting a little tight with all your activity and addition of a regular Active Isolated Stretching routine would take care of your problem. Look in the sidebar to the right for Specific Stretching for Everyone by Aaron Mattes. You’ll find great stretches in this book for every muscle in your body. It’s a good investment.
Hi James, Yes, definately this is a problem with your popliteus muscle! Your symptoms are classic, but your doctor may not know about it because it is deep between the bones of your lower leg and is rarely treated. The medical text on Trigger Points in the lower body, Myofascial Pain and Dysfunction by Travell and Simons Vol II wasn’t published until 1991, so many doctors are not educated about these muscle pain symptoms. What they know is mostly about joints and nerves. Stretching this muscle is a bit awkward and is best done with the help of a friend. Sit down with your heel propped up on the floor in front of you. Hold your thigh steady with your hands and rotate your foot outwards. Hold the stretch for two seconds and repeat it 10 times. If you have a helper, sit back in the chair with your leg straightened out in front of you. Have your friend hold your foot at the heel and forefoot. You hold your thigh steady at your knee. Start by rotating your foot outwards as far as you can. At the end range, have your helper continue the rotation past where you can go yourself. Hold the stretch for 2 seconds and repeat 10 times.
If you have another spasm, use an icepack at the back of your knee for up to 5 minutes to calm the spasm and increase blood flow. Blood is essential for healing, stops muscle spasms, takes away the heat of inflammation and removes waste products that cause pain. Ice can be reapplied when your skin is warm again and can be used several times a day when you’re in trouble. 1000mg of vitamin C right after vigorous exercise will help as well as a big glass of water.
I injured my leg at work struggling with an aggressive patient I had a severe pain in my calf and inside of my knee. I went to the doctor and was told I had a calf strain. I was given physio and told to ice the injury. It has been 2 months and my leg is still very painful but mostly when I weight bear and do to much walking or stairs. The most severe pain is inside the knee at the top and on the inside of the knee more towards the upper part of my leg. My knee has periodically given out and not supported my weight but only when doing stairs. Recently I went to a knee specialist and was told I have a plantaris tear? I am in an extreme amount of pain after walking and can not run. I had an MRI which suggested a osteochondrial injury and a bakers cist. Both of which the specialist disregarded because when he manipulated my knee I did not seem to be in pain. If you have any thoughts it would be much appreciated. Thanks. Merry
Hi! I am so glad to find your blog…..My 10 year old said that when he was running home from school yesterday when he suddenly felt a pop behind his knee cap. His leg cramped up and it was painful to straighten it out…. He walked with his leg bent all last evening, went to bed and when he woke up it didn’t hurt anymore and he could walk normally. But then at school today, the “pop” happened again and he is walking with his leg bent again. I am wondering if this sounds like the popliteus muscle problem…This is of course Friday and we thought we would take him into the doctor on Monday. What do you think is the problem here? I would so appreciate hearing your thoughts and what can be done? It is sad to see an active 10 year old boy sit in class during recess because he can’t run with his buddies. :( Thanks for your help!
Hi Anne, Hopefully this helps a little before you go to the doctor. When I think of a pop behind the kneecap I think of a ruptured ligament, but I don’t think that’s it because there was no event or trauma and the pain stopped with rest. The popliteus is at the back of the knee and below it, not behind the kneecap. The test there is whether he can’t crouch because of pain behind the knee or a sensation of swelling there, like there’s a ball where the knee bends. My suspicion is that his quadriceps are cramping and pulling the kneecap (patella) back against the bony joint of the knee. The patella is a sesamoid bone, meaning that it floats within a tendon rather than attaching to a bone, in this case the quadriceps. When the quads are tight it could mean the patella is rubbing on the bones beneath it causing a sound that he could be describing as popping. The quads straighten the knee, so that makes sense that if they are cramping he would limp, being unable to straighten the leg to walk. Resting a muscle allows it to recruit what it needs to do work. As soon as he starts using it again, the muscle runs out of fuel. When a muscle is tight, it doesn’t get enough blood and blood carries the fuels and takes away the wastes that cause pain. Try massaging his thighs and using alternating ice and heat for up to 5 minutes each.
The other logical reason would be the hamstrings in the back of the thigh. They attach at the sides of the knee joint and bend the knee. Cramping there would prevent straightening the leg because the muscles are shortened. Treatment would be the same, massage and ice or alternating ice and heat.
Lastly, If he’s growing fast, his bones might be growing faster than his muscles. The same treatment would apply. Massage brings blood to help the muscles grow and keeps them from cramping. If when massaging you find knots in the muscles, hold pressure on them for 10-20 seconds to stop the muscle from firing, then do long strokes toward the heart to flush out the wastes. Good luck.
Hi Merry, It sounds like the popliteus to me in your description of the pain. The plantaris could easily be injured, but it is a tiny muscle and works to invert the foot. It isn’t in your calf and doesn’t attach to the inside of your knee. The popliteus matches in both instances. The medial gastroc could be injured. Both muscles are used in a bent-knee position, the popliteus to hold back the femur on the tibia, and the gastroc to actually bend the knee and stabilize it in that position. The other possibility is the medial hamstrings which cross the joint and would be felt both above and below the inside of the knee.
A Bakers Cyst wouldn’t necessarily hurt with manipulation, but a tear in the joint tissue would. So I would recommend finding a good therapist who knows the deeper muscles really well and can be effective treating them. You can stretch the gastroc and hams, but the popliteus is hard to work effectively. Try the manual work and do some icing regularly and often for 2-5 minutes. Look in the search box in the side bar for the post on the ice and heat controversy. Let me know if this helps.