Swelling after knee surgery is a rather common, normal finding. Many patients ask me if their swelling is normal, how long will it last, and is it dangerous? These are all great questions.
First, let’s understand what swelling is and why it happens. Swelling can mean more than one thing. The development of fluid in a knee joint, in doctor-speak called an ‘effusion’. This is not the same as swelling in the tissues around your knee or in your leg. Swelling occurs as a natural part of the inflammatory response to injury. There may be very little after a simple procedure like a knee arthroscopy, or more swelling after a joint replacement.
After a knee scope, or arthroscopy, it is common to have swelling, or an effusion, in the joint for a few days, or sometimes, as long as a few weeks. Patients with arthritis tend to be swollen longer. Patients that have a knee replacement surgery can have knee swelling, or a knee effusion as we call it, that lasts for months.
After a big knee surgery like a ligament repair or replacement, you may have some of both – fluid in the knee joint (effusion) and swelling in the leg. This often lasts for several weeks. Sometimes, I see people that are still swollen several months later (without any pain) and I believe this can be normal – everyone is different.
What does knee swelling look like ?
Ultrasound image of fluid in the knee joint
Knee swelling in the joint, or a knee effusion, is rather easy to see on ultrasound. It looks like a large black area on the image that can be moved around. Here is a picture from a recent patient of mine showing a large joint effusion. The arrows show you the edge of the tissue above the swelling, and the lower white line is the front of the femur bone. The fluid is sitting in between the two.
Is knee swelling dangerous after surgery?
It is normal to have some swelling after surgery. Don’t be alarmed. There can be bruising as well and discoloration of the skin. This will resolve with time and does not need to be alarming. If you are worried, please come in and see me in the office to check.
How to reduce swelling after surgery
Compression stockings
There are several simple things you can do. First, wear a pair of ‘TED’ hose, or compression stockings. This will help to literally ‘squeeze’ the fluid out of your legs and feet. You can wear these almost 24 hours a day.
Elevation
Keep your leg up and elevated. The higher the better. This will help to drain fluid out of your leg. Try using a few pillows under your calf. Get it above your heart.
Ice
Ice your knee. This can be done with ice packs, or with an ice machine – a special pad and a pump that circulates cold water through the pad like the one shown here. The cold helps to reduce inflammation which will decrease the swelling and effusion.
Ibuprofen / Naproxen or other anti-inflammatory medicine
These medicines work to stop inflammation and thereby reduce the swelling after surgery. I often suggest 600-800mg of ibuprofen 3 times a day, or 440mg of naproxen (Aleve) twice a day. Be sure to check to see if this is something you are allowed to take after surgery. Patients on strong blood thinners should not take any anti-inflammatories.
I’ve put a number of products that I’ve seen help patients with knee swelling on my related products page. I don’t sell these but refer you to amazon to find them. Click here to shop.
Patients ask a lot of questions about swelling – feel free to ask me below if you have some of these questions and I’ll try to answer them for you. I want you to understand what knee swelling means and when it is important to see your doctor.
Please don’t take this all as direct patient advice. I am happy to see you in my San Diego, California office OR if you are from out of town or the country, I continue to do telemedicine visits. Contact me to set this up. I look forward to meeting you.
I have many blog posts like this one about orthopedics, regenerative medicine, surgery, robotics and more. Check out the menu toward the bottom of the page in the BLOG section, or more common situations under ‘CONDITIONS‘ and ‘TREATMENTS’. Also, feel free to comment below.
I had knee replacement over three years ago and the knee is still swollen. Looks just like the pictures above, One knee is normal and the other (with the replacement0 is swollen.
Hi Sandra
That’s a long time for your knee to be swollen after surgery. First, I’d get back to see your surgeon, get a new set of x-rays, and see if there are simple answers to understand the swelling. Some knees may never go down, but are pain free. It is always a good idea to be sure there is nothing concerning going on. Your surgeon should be able to figure this out – at least for the bad players. In the absence of loosening or infection, we sometimes have a hard time really understanding why it persists. Everyone is different and I cant really give good medical advice here-but would advise a second look for sure to see if anything can be done. All the best ! SH
Hi. I got a knee surgery more than three months ago. The swollen and pain are as bad as before the surgery. I insist in having a new MRI taken and the results were as I suspected. According to the MRI, I still having a torn meniscus, but my doctor said that he is no agreed with that diagnosis. I tried to look for a second opinion, but this group of doctors didn’t want to take my case. Im very concerned at this time and I feel like my doctor has left me on my own. Unfortunately, Im not any closer to go to see you. Im currently living in Greenville SC. Could you please advise.
Dear Fabiola – sorry to hear of your knee troubles. While I cannot give real medical advice, I think understanding what your doctor is saying is very important. Remember, we treat patients, not your MRI scan. What you see on the MRI needs to correlate with what we as orthopedic surgeons think is important. There are excellent orthopedic surgeons there in Greenville. Take a friend, or loved one with you to help understand what your doctor is saying to know what is best for the next step. Listen carefully and ask questions. Best wishes, SH
I would get a second opinion at a different orthopedic place if I were you.
I love second opinions. These can be so helpful. It’s ok to question your care. Its your body. I welcome patients, and some times encourage them, to see a colleague who may have a fresh perspective on a problem. That way we can collaborate on the best treatment for you. Good suggestion for sure.
Hi sir i have patient with knee scope- about two weeks but have swelling shall i put ice for here ??
Ice is one of the strongest anti-inflammatories we know and is so easy to use. Be sure not to leave it on too long to cause any skin problems. I often have patients ice their knees for the first 2 weeks after surgery, sometimes longer if still swollen. I would also have a therapist get involved to help assess the joint. I typically recommend icing 20 minutes on, then take a break for 20-40 minutes.
Hello,
My wife had a knee arthroscopy in her left knee about 6 months ago. One month after surgery the area right above both of her knees swelled up to the point where it is inhibiting her walking and she has been out of work, and is in danger of losing her job. They’ve done ultrasounds, MRIs, dopplers, etc. They cannot figure out what is going on. They’ve tested for Gout, Lyme, and nothing has come of it. We’ve seen an Orthopedic Doctor, Rheumatologists, Lymph-edema specialists, and no one can figure it out. They are acting like she has some rare condition they have never seen before. Have you seen anything like this before?
My son just messed up his knee from football and we’re worried that it might derail his football career going into college. I liked that you said to put ice on the knee and elevate it after surgery. We’ll have to talk to the orthopedic doctor and prep my son for surgery.
Injuries are always challenging for young athletes, and their parents. I’d definitely get seen by your orthopedic surgeon to get a good plan going forward if college play is on the line.
I had ORIF on left patella almost 9 months ago and went back to work for one week only 40 hours, (3 hours walking 5 sitting )and can barely drive knee, leg and foot swollen to double normal size…. and iced and elevated over weekend, got another Xray at urgent care–and its healed but effusion—–
Isn’t that quite long time to be swollen like this????—–scared and no insurance for Ortho right now–
know you cant diagnose over Net just been told this should NOT be like this 9 months post surgery THANKS
Yes – that is a long time to be swollen. First, is the patella fracture healed ? The usual answer is yes at this point. It may also depend on how the fracture healed, do you have any underlying arthritis, or other conditions in the knee. These are all potential contributors to continued swelling. As you know, seeing your doc would be best. In the meantime, ice and NSAIDs are typical treatments for persistent swelling after something like this. I also worry about infection if it is hot and red and swollen. That often needs to be seen right away, although unlikely. Best wishes.
How much time each day should I have my ice flow machine on my knee replacement which is 6 days out from surgery.
For my patients, I have them use it for about 20 minutes every hour or two. I also suggest to never use it while sleeping – these machines get VERY cold and can cause frostbite and kill skin. Be careful. Talk to your surgeon about his specific recommendations for your knee, your skin, and your situation!
Hi I head two surgery’s for septic knee got infection from cortisone shot no more on antibiotics knee is swollen and very stiff going on 6 weeks is this normal
Hi Doctor !
I had partial meniscus removal arthroscopic surgery 2 weeks ago . The surgeon cut and shaved both lateral and medial as I had two tears ,he also found joint arthritis at 1.5 scale .
Today is my 15th day , am having difficulty with inflammation , swelling despite am using my water therapy machine almost 7 hours a day, if I move on my legs for like 10-15 minutes my knee will turn sore warm and swollen .
Am taking potassium diclfenac NSAID 50 x2 daily to help with swelling and inflammation .I started PT and my range of motion was 90 now it’s 120 and extension was -10 now it’s -2
Is this swelling normal ? My surgeon advised that I need to keep cold therapy to get the swelling off .
I had an arthroscopy 13 years back ( am 42 now) but i didn’t have this swelling and recovery was very smooth .
I would like to know what shall I do ?
Hi
These are GREAT questions and something everyone should learn from. You had surgery 13 years ago and it was really smooth but now, 13 years later, your knee is still really quite reactive after surgery two weeks out. This really isn’t that surprising. You’ve definitely done a lot of walking in the last 13 years. I’m sure your knees looked much better inside than they do now. The severity of your arthritis has a huge impact on how much swelling you will have after surgery. It may take some time for this to go down. I’ve seen some patients go a few months before the swelling seems to resolve. It just takes a lot longer to recover after knee arthroscopy when you have arthritis then it does if you had an otherwise perfect knee and a meniscus tear. This is definitely something I think I will spend some more time writing about. Thanks so much for your question. All the bes.
Hello,
I had a knee arthroscopy about 2 months ago on my right knee ( both knees bone on bone) it took me 14yrs to get that done due to the doctor, wanting to continuously give me injections due to my age (42) Since the scope my knee has been so swollen I can barely walk sometimes, they keep telling me it’s normal. One month after surgery I fell on the same knee and I feel as if my knee cap moved. I am being treated for RA but this can’t be normal my knee feels worst know than it has ever felt. The doctor also did a ligament repair but now my knee just slips whenever it wants to, this can’t be safe. I know I can’t get medical advice from you, but can you tell me if it’s too soon to have the fluid drained so that I can get some kind of relief????
Hi Doctor,
I have water retention in my ankle and knees. I haven’t done any surgery before. I just was taking brexin medication for my knee pain. Now I have fluid in my knee and ankle. How this can be cured. I stopped the medication since I got the water retention. Please let me know what should be done to remove the water from my both legs.
Thank you
Hi Fay. I’m not sure what ‘brexin’ is – not a common medication name here in the US. Swelling in your leg and ankle can mean a lot of things. This is important to have a checked out. It is not unusual for patients with heart conditions to develop swelling in both legs. Whenever I see this, swelling in both legs and ankles, I tend to refer patients back to their primary care physician or heart specialist to see if there is a medication they might need, like a water pill, to help reduce the swelling. This may have nothing to do with your knees at all. It’s hard to give specific advice, but I would definitely be seen for this
I had an arthroscopy/lateral release/chondroplasty and removal of loose bodies, on top of finding out that I have traumatic arthritis at the ripe old age of 28. 2 and a half months on and I still have swelling. If I’m on my feet for more than a few of hours at a time straight my knee gets hot and flushed and I have to put a cold pack on it to get the colour back to normal. I took antibiotics a month back. Is this normal this long after surgery? I do strengthening exercises every day. I don’t want to ask my surgeon. He has horrible people skills.
Your surgery sounds like a rather typical type of procedure. You do mention there is some arthritis going on. This is always the big culprit that causes continued pain and swelling. This usually happens if the knee remains inflamed for a while. It may not be an infection at all. Sometimes the strengthening exercises will continue to flare up the knee and what it really needs is to not be pushed too hard. I think it’s important to understand how severe the arthritis is in your knee. Everyone is so different. The locations of this arthritic wear are always unique for each person and will influence how long your knee tends to stay swollen after a surgery. I hope this helps. It would always be best to be seen for it. Sometimes I consider a Cortizone injection about 6 to 8 weeks out following surgery to help calm the knee down if it is not resolving on its own. Maybe something to think about. Again it’s hard to give specific advice and it would be good for you to see a doc that you can talk to you and trust. If his people skills are terrible, it may be time to find a new doctor :-)
Hey doctor
Is it normal to have a swelling after two months of synovectomy of the knee ( i had a pvns )
Hello I broke my femur 🦴 Oct 27 and fractured it right above my knee my knee is still swollen,do you know the time frame should I see less swelling
on 1/17/20 i had knee surgery.I took therapy and my knee still swelling today.it deeply aches with pain well i had a lady come from the hospital to check on my knee and when she sat down she told me my knee swelling is all a (big joke,) i said why is it a joke+ i pulled up my dress so she could watch my knee it swelled big that day and it made me sick by the time she left she said” i can see you are not joking about your knee swelling” it was huge. ice or heat makes it swell big and i have a bad time walking It burns and gets hot to the touch. my dr. said there is nothing wrong with leg and when i was getting dressed he said wait that leg is shiny lets take xrays, it was swollen but he said if he takes swelling out it could get worse, but why do they want to have me take therapy agailn although they let me go before they colud not help me. my nerve above the left side of knee they had to pull up it had sank down . doctors do not wnt me to talk about it cause it is a joke Why. I have never had this told to me before but the swelling makes me sick now they say artherist which maybe, but why constant pain so bad i go to sleep i get two sick with the pain i was given a shot but did not work at all. jaydearing25@gmail.com
I would suggest seeing an orthopedic doctor, get weight-bearing x-rays of your knees, and see how bad the arthritis may be. Osteoarthritis is like wear and tear of a set of car tires – they wear down over time. The x-ray should help your doctor figure out how bad they are and what the best treatments may be. I’ve written a lot about osteoarthitis on my website here. Here are a few links:
These are just a few. There are so many more.
Keep me posted.
Hi I just had a small ganglion cyst removed from behind my knee cap over a week ago. Also a small amount of damaged tissue scraped off back side of knee cap in orthoscope type surgery with 3 incisions. I ice it every two hrs or every hr for 20 minutes. The swelling has increased over the past week.
I get the chills and sweats out of no where. The pain isn’t getting better. My range of motion is much less than first p.t. Session. I can’t take aleeve or Advil cause it makes my b.p. Sky rocket. The Doctor said I could be back to work in 4 weeks?! But there really isn’t any improvements. Any suggestions. I was a healthy in shape 41 year old man and it’s very discouraging.
Hi – Sorry to hear of your knee struggles – it sounds like you have damage to your cartilage – a chondral injury – on your kneecap. I’ve written more about chondral injuries HERE. This is a tough problem. Its hard to give solid medical advice here on the website but i would discuss more with your doctor about the condition of your knee and possible treatments for this. I use a number of injections for cartilage damage before considering surgical options such as PRP. Try to find out more what is going on. Happy to see you in San Diego for this ! All the best, SH