You have recently undergone a total knee replacement surgery, and you are concerned or curious about the swelling you are experiencing. you want to know how long it will last and what you can do to reduce it.
I have written this article specifically to provide reliable answers to these questions, which are often asked by total knee surgery patients.
As a diagnostic radiographer I have seen so many patients who come for x-ray with swollen knees after surgery. For this article I have consulted an expert surgeon on total knee replacement and of course scientific publications.
Happy reading!😀
Have any questions, remarks, or experience to share? Feel free to use the comments section at the end of the article!🙏
Last updated: May 2024. Written by Juliet Semakula, diagnostic radiographer.
Disclaimer: no affiliate links.
Basics:
Total knee replacement is a common orthopaedic surgery and one of the most successful surgeries.
Complications after knee replacement surgery are rare but persistent pain and swelling are the most common complaints after knee replacement.
To answer some of the common questions asked about swelling after a total knee replacement.
I consulted some of the medical literature using PubMed to search for articles published using the terms knee oedema, effusion, swelling, knee arthroplasty, knee replacement, total knee arthroplasty.!
I was able to review some of the causes of swelling after a total knee replacement.
What do we mean when we say ‘swollen knee’ in medical terms?
In everyday language, we use the terms swollen or puffy knee to describe a knee that appears larger than normal. In medical terms a swollen knee is called edema which means the something.
▶️How do I know if the swelling is normal ?
Swelling of the knee is normal after surgery of a total knee replacement and is usually moderate to severe in the first week but gradually decreases for the next weeks and months.
Some swelling can be normal even up until 6 months post-surgery.
According to scientific studies Swelling of the knee after knee replacement surgery occurs because of the accumulation of excess fluid in the tissue of the knee joint. The difference can be 2-3cm ,5-6 cm or even more.
This is a very common occurrence which does not necessarily indicate a problem.
Knee replacement swelling
▶️Where does the excess fluid come from?
Inflammation: During surgery, the skin, soft tissues, and bones are cut through. so these take time to heal, which may cause excess fluid accumulation in the tissue as a part of the inflammatory chain leading to healing.
The swelling persists even after the skin incision heals as the tissues in the body take a long time to get back to their condition after the surgery.
Summary: Inflammation is a very healthy and therapeutic response! It is an automatic reaction of our immune system which helps to repair the damaged tissues.
Reduced activity results in decreased fluid circulation and increased fluid accumulation. Anatomically, swelling can occur within the joint or outside the joint capsule.
You may complain of swelling around the knee, below or above as the image below. The swelling may get worse at the end of the day when you do your normal activities.
Swelling caused by intra-articular fluid accumulation inside a joint is called effusion.
Swelling outside the joint capsule mostly originates from edema of surrounding soft tissues, these include bursa, muscles, subcutaneous fat, and skin.
⚠️Caution!⚠️ swelling can be more significant in some people, due to various factors such as genetic predisposition, obese, weak quadriceps muscles or other loss of a lot of blood during the surgery and health problems (vein or heart failure).
▶️ ️ Understanding other symptoms of a swollen knee replacement.
You will notice these symptoms often when you have had a knee replacement:
🟣Your knee will feel a tight band, hard, red, and shiny.
🟣Bruises that will seem blue, purple, or yellow will appear.
🟣Increased size or volume of the knee and foot.
🟣Stiffness and limited range of motion in the knee.
🟣Your knee may feel warm on touch or redness.
It is very understandable that these symptoms may be concerning at times. But it is not something to be alarmed about. It is something that happens after knee replacement.
Try not to worry too much about the size of the swelling after a total knee replacement or if swelling lasts for several months.
But you can always talk to your doctor or therapist if you need some reassurance.
▶️ When should I worry about swelling after knee replacement?
One thing you should understand that will ease your worries is:
⚪General pain and swelling may occur for up to several weeks following knee replacement.
⚪Swelling typically lasts for 2 to 3 weeks after surgery but may persist for as long as 6 months.
⚪Bruising may last for 1 to 2 weeks following surgery.
It is important to pay attention to how it’s affecting your daily activities. Can you move around comfortably and perform the tasks you need to do? If the answer is yes, then there is no need to worry.
However, if you are concerned it is always good to consult your doctor and present your worries:
▶️What are the signs that swelling is not resolving normally?
Sometimes swelling may also occur because of serious complications after surgery such as deep vein thrombosis or prosthetic joint infection which can be treated.
♦️ Prosthetic joint or wound infection: there is a small chance that your knee wound could get infected after the operation which is usually treated by antibiotics.
♦️Deep vein thrombosis is possible after knee replacement because of how the blood flows and clots after surgery. This is often not serious.
But if you have a blood clot that causes swelling and pain consult your doctor and he might give anticoagulant medicines to help.
▶️How do you get rid of swelling in your legs after knee replacement?
It is totally natural to be worried about knee swelling and you are looking for a way to reduce it quicker.
However, there is no miracle solution or medical way to help reduce swelling.
There are some recommended ways that can help relieve swelling but most of them are sought not to be effective for short or long term to reduce swelling.
🟧Physiotherapy methods such as cold therapy, massage, compression therapy wearing compression stockings.
🟧Ultrasound therapy
🟧Manual lymphatic drainage.
Usually, your doctor will recommend some of these home remedies that may help reduce the swelling, but you should remember they are for the short term. If you stop applying them, the swelling is likely to return.
🟣Regular icing around the knee, use an ice pack as cold temperature helps in the control of both pain and swelling.
Icing is said to induce narrowing of the blood vessels in the region which will help in the decreased flow of fluid to the area which in turn will reduce swelling.
🟣Elevating your leg just above your heart level helps in flow of the fluid back to the body from the leg.
🟣Simple exercises such as pushing your ankle up and down repeatedly as in the image below. This kind of movement has been associated in helping the calf muscles to contract which helps to reduce the swelling and prevents deep vein thrombosis.
🟣You can also wear compression stockings; they do help reduce swelling and prevent blood clots.
▶️Does walking reduce swelling after knee replacement?
Yes, walking is said to be good for reducing swelling after knee replacement surgery.
🚶Walking increases blood flow to the tissues, which can help reduce knee inflammation and swelling.
🧎Walking can help relief Joint stiffness and weakness:
🚶Walking helps build muscle strength and joint mobility allowing your muscles to contract and relax which helps to pump fluid and blood through your body.
The increased circulation can help to reduce swelling in the affected knee.
⚠️Caution! ⚠️avoid High-impact activities like running or jumping in the early post-operative period to prevent worsening the swelling. Gentle stretching and low-impact activities like walking and cycling are encouraged.
▶️When should you start walking after surgery?
You’ll start standing and walking on your new knee almost immediately, just a few hours after surgery.
Movement is key to a successful recovery. At first, you’ll take short walks, for example, from your bed to the bathroom and around your room. Then when you feel ok within yourself a few weeks after your surgery you can start taking short walks.
Typical recover timeline from NHS surgeons and physiotherapist
| Stages | Recovery time |
| Less pain | A few days to a few weeks. |
| Swelling and bruises disappear | A few days to a few weeks |
| You start walking with a crutch or walker | From next day after surgery |
| Walk without crutches | After 1 to 2 months |
| Shower without special equipment or support | After 1 to 2 months |
| Resume simple sports such as cycling | From 1 to 3 months. |
Remember the recovery timeline can be different for everyone, just be patient and focus on things that will help speed up your recovery.
Hope I have given you some reassurance! Wishing you a quick recovery!🙋
Below are some of the resources I have relied on. Any questions feel free to leave in the comments section.
📚Source:
Yau LK, Henry FU, Man Hong C, Amy C, Wai Kwan Vincent C, Ping Keung C, Kwong Yuen C. Swelling assessment after total knee arthroplasty. J Orthop Surg (Hong Kong). 2022 Sep-Dec;30(3):10225536221127668. doi: 10.1177/10225536221127668. PMID: 36122907.
Gupte C, St Mart JP. The acute swollen knee: diagnosis and management. J R Soc Med 2013; 106: 259–268.
O’Driscoll SW, Giori NJ. Continuous passive motion (CPM): theory and principles of clinical application. J Rehabil Res Dev. 2000 Mar-Apr;37(2):179-88. Erratum in: J Rehabil Res Dev 2001 Mar-Apr;38(2):291. PMID: 10850824.
Gao FQ, Li ZJ, Zhang K, Huang D, Liu ZJ. Risk factors for lower limb swelling after primary total knee arthroplasty. Chin Med J (Engl). 2011 Dec;124(23):3896-9. PMID: 22340316.
Gandhi R, Santone D, Takahashi M, Dessouki O, Mahomed NN. Inflammatory predictors of ongoing pain 2 years following knee replacement surgery. Knee. 2013 Oct;20(5):316-8. doi: 10.1016/j.knee.2012.10.015. Epub 2012 Nov 14. PMID: 23157967.