Have you just had knee surgery, and you are wondering why your knee is still swollen even after months of surgery.
Am here to give you some reassurance on understanding the dynamics of knee swelling after surgery, to help you in managing expectations and optimising recovery strategies
Summary: With proper care, monitoring, and obedience to post-operative instructions, the impact of swelling can be minimised, paving way for a smoother recovery and return to activity.
Happy reading!😀
Any questions? remarks? Let’s meet in the comments section at the end of this article.🙏
Last updated: Nov 2024. Written by Juliet Semakula a diagnostic radiographer
▶️What is knee inflammation in concrete terms?
Knee Inflammation is a response to an illness, injury or something that doesn’t belong in our body like germs.
Inflammation is a normal and important process that allows your body to heal.
When a tissue in the body is affected for example an infection, immune cells like macrophages and neutrophils.
⏩Are recruited to the injured area.
⏩Then release chemicals to protect and heal the damaged tissues.
In the process of all this, the cells can trigger blood increase in the diameter of blood vessels to allow cells to arrive more quickly at the injured area.
These reactions can incidentally lead to mild side effects such as
🔴Swelling.
🔴Pain
🔴Redness and heat.
🔴Loss of function such as stiff band feeling.
This is how you know your body’s inflammatory system is working correctly when you’re ill.
Knee Inflammation occurs when excess fluid collects in or around the affected knee causing it to swell. Fluid builds up in the knee joints. Which sometimes in medical terms it is referred to as Edema.
Images of knee inflammation after surgery: x-ray and post operation scars views
▶️How do you know if it’s inflammation and not something else?
Some people usually confuse knee inflammation with infection or other medical conditions
A knee infection is much rarer and slightly more worrying caused by bacteria, viruses or fungi. You may only have knee swelling without pain sometimes
Often you will have a fever or chills as an additional sign when there is an infection along with unusual fluid drainage from the incision.
Also other medical conditions may also cause knee swelling with or without pain. For example:
🟤Septic bursitis, which is an infection in the knee, you may have symptoms like the flu, swelling and pain can be seen late when the infection progresses.
🟤Prepatellar bursitis is an inflammation of the bursa In Front of the kneecap caused by repeatedly kneeling for an extended period.
🟤Rheumatoid arthritis can cause swelling and aching in the knee. It can also present as an aching in the muscle.
🟤Osgood Schlatter disease were the growth spurts in teens and is mainly around in the area where the tendon from the kneecap connects to the shinbone. This can cause swelling with no pain.
🟤Tumour in most cases causes your knee to swell but, in some cases, there may not be pain. You may only feel pain at night.
Usually with inflammation you will experience the following symptoms and signs.
🔴Swelling around the skin of your kneecap will puff up noticeably and you will be able to tell the difference with your other knee.
🔴Stiffness when your try to bend the knee because the excessive fluid build-up in the knee joint
🔴Pain that might feel severe to the point you may find it had to put weight on your leg.
🔴Your knee will feel warm and reddish.
Since your operation, if you have not had any other symptoms, it is very likely to be just inflammation. But if you are worried it is always good to discuss this with your doctor.
▶️Why is there inflammation after knee replacement surgery?
After knee surgery swelling and pain are the most common complaints among patients I see in X-ray
For some reassurance: knee swelling, or inflammation is very normal even after 6 months after knee surgery.it is usually moderate to severe in the first week but it will gradually decrease for the next weeks and months.
What causes inflammation after knee surgery?
1️⃣Inflammation chain that helps with healing is a normal mechanism of the body’s response.
During surgery, the skin, soft tissues, and bones are cut to perform the surgery.
As they take time to heal, there may be excess fluid accumulation in the tissue as a part of the inflammatory chain leading to healing.
2️⃣Surgical impact
During surgery the metal and plastic parts are inserted in the knee joint to allow motion and good alignment of the natural joint.
These can take time to adjust to the new joint causing you pain and swelling during the healing process.
Intraoperative image showing metal and plastic parts inserted in the knee joint to allow motion and good alignment.
3️⃣Blood vessel changes
Surgery can affect blood flow dynamics around the knee contributing to fluid build up around the knee joint causing redness and warmth.
4️⃣Deep thrombosis
After such a major surgery there is a significant risk factor for deep vein thrombosis because of the formation of a blood clot inside the veins of the legs.
All these factors cause inflammation around the knee joint which is a necessary step and is beneficial in the medium and long term, it is what allows damaged tissues to be repaired and heal.
▶️Key points to watch out for as you go through the healing process.
Inflammation is something very healthy and even healing! It is an automatic response of our immune system.
⚫Immediate knee swelling after surgery is normal because your body is reacting to surgical trauma, and it is part of the healing process.
⚫Swelling will decrease in the first few weeks a sign of healing.
⚫Slight swelling after 6 months is also normal, but it should progressively lessen as recovery continues.
After surgery you will be given a follow up appointment from your doctor. To monitor the swelling because it helps to give a clear picture if you are healing well without any other complications.
▶️Risk factors for prolonged inflammation.
While swelling after knee replacement is seen as normal in the first months of healing but at times swelling may present as a serious issue if it persists longer than normal.
Do we know what causes some people to have more inflammation than others after knee replacement?
Here are some suggestions according to some medical research:
♦️knee swelling after total knee replacement is related to having a high hidden blood loss during surgery.
♦️Or having a high body mass index (being overweight).
Gao, 20211
▶️Issues of concern of prolonged inflammation
If the acute inflammation does not quickly resolve, and persists beyond 6 weeks, it transitions from subacute to chronic.
♦️It can lead to tissue damage and fibrosis.
♦️ Infection around the prosthetic joint may cause discharge, fever, pain and redness around the knee.
♦️Deep thrombosis
♦️Pre Existing medical condition such as diabetes or heart disease
♦️ Nutrition and medication can affect inflammation and fluid balance in the body.
♦️Activity level after surgery can exacerbate swelling.
▶️How long does inflammation last after total knee replacement?
To assess the duration of inflation various parameters can be considered such as.
🟠Skin temperature
🟠 Pain
🟠Swelling or Oedema
I will rely on the study done by Lohchab 2021and others to evaluate the progression of inflammation.
1️⃣Duration of inflammation based on the skin temperature.
A research team evaluated the progression of inflammation in the 90 days following a total knee replacement.
Individuals with knee osteoarthritis who had undergone bilateral knee replacement above the age of 63 years were involved in the study.
The results are as follows.
🟣 Skin temperature was calculated and investigated after surgery, and it was observed that inflammation was at its maximum 2 days after surgery.
🟣It remains elevated until the 6th day after surgery.
🟣 It will continue to decrease as the days go by.
🟣 Finally, it returns to normal levels 3 months after surgery.
You will generally feel the warmest on your knee 2 to 6 days after surgery. Then the knee’s warmth will decrease, returning to normal on average after 3 months.
2️⃣Duration of inflammation based on pain.
The study evaluated post operative pain development within the first 4 weeks after total knee replacement.
🟣Pain showed a constant decrease in the first day after surgery and steadily decreased on day 8.
🟣On day 9, the pain increased again.
🟣Then on day 10 a continuous decrease in pain intensity was noted. 30 days after the operation, it averages.
(Schindler 2022)
3️⃣Duration of inflammation based on knee swelling.
🟣Swelling will be more pronounced around the 3 and 4th day of postoperative or the 6th and 8th day. You will feel it more at the lower leg on the operated side. (Gao 2011, Loyd 2020)
🟣Your operated knee increases in volume by an average of about 35% compared to before the operation.
🟣At 3 months, on average, the volume is still increased by 11% on average
This means that in a significant proportion of people, there is still some inflammation 3 months after the operation. knee inflammation will eventually go away thou in some people it may be an ongoing problem
This inflammation does not necessarily prevent a gradual return to regular activities!
▶️How to manage swelling just after knee replacement.
Effective management of knee swelling after surgery is very important for a successful recovery in the first days after the operation.
Patients are sometimes given anaesthesia intravenous glucocorticoid injection via nerve blocks (Yang 2022; Wu 2020).
However, the goal is not necessary to stop inflammation because it is a process that helps repair tissues.
The main objective is to stop or alleviate pain, improve satisfaction and to allow mobility
Here are some of the things you can do at home to help reduce swelling after knee surgery.
♦️ Medication
♦️ Knee elevation
♦️Apply ice regularly because it is recommended to reduce knee swelling.
♦️ Compression socks
♦️Physical therapy exercises with time.
You can read a full article on swelling after knee replacement
▶️I have had people wonder why heat makes inflammation worse.
Heat has the opposite effect of ice, it causes small blood vessels to open which can stimulate inflammation rather than relieve it.
Heat treatments should be used for chronic conditions such as old injuries to help relax and loosen tissues and stimulate blood flow to the area.
While cold numbs the affected area, which can reduce pain and tenderness. Cold can also reduce swelling and inflammation.
▶️Total knee replacement pain at night. How to cope.
After a major knee surgery, sleeping can feel almost impossible. This usually happens due to total knee replacement pain at night.
The good news is it’s true your body does a lot of healing at night after surgery. You can sustain the pain with pain medication to help you find balance between healing and sleep.
Why do you feel more pain at night after a knee surgery?
1️⃣While you lie down to sleep, your body, brain, digestive system and muscles relax, in the process focus will be on growing new tissue and restoring your health.
Pain is different during daytime, because you are actively moving which allows your body to send blood flow and nerve signals to these areas, which distracts you from feeling knee pain after surgery.
2️⃣Physiological mindset: sometimes we tend to focus more on the pain even when it is not there and when you do so you will feel pain and discomfort more.
▶️How can you cope with the discomfort:
♦️Try sleeping on your back, this will keep your leg straight which helps to promote blood flow.
♦️You can also sleep on your side but make sure your operated leg is facing up and not touching the bed, this helps to reduce pressure on the knee.
♦️Use things like pillows for support under the entire length of your leg and calf to help prevent bending.
I have come to the end of this article. I hope I have answered some of your questions.
Wishing you a quick recovery!🙋
📚Source
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Banik RK, Sia T, Ibrahim MM, Sivanesan E, Uhelski M, Pena A, Streicher JM, Simone DA. Increases in local skin temperature correlate with spontaneous foot lifting and heat hyperalgesia in both incisional inflammatory models of pain. Pain Rep. 2023 Sep 12;8(5):e1097. doi: 10.1097/PR9.0000000000001097. Erratum in: Pain Rep. 2023 Nov 02;8(6):e1104. doi: 10.1097/PR9.0000000000001104. PMID: 37711430; PMCID: PMC10499105.
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.
Schindler M, Schmitz S, Reinhard J, Jansen P, Grifka J, Benditz A. Pain Course after Total Knee Arthroplasty within a Standardised Pain Management Concept: A Prospective Observational Study. J Clin Med. 2022 Dec 4;11(23):7204. doi: 10.3390/jcm11237204. PMID: 36498779; PMCID: PMC9741301.
Wang D, Xu J, Zeng WN, Zhou K, Xie TH, Chen Z, Yu HD, Li JL, Zhou ZK, Pei FX. Closed Suction Drainage Is Not Associated with Faster Recovery after Total Knee Arthroplasty: A Prospective Randomised Controlled Study of 80 Patients. Orthop Surg. 2016 May;8(2):226-33. doi: 10.1111/os.12247. PMID: 27384732; PMCID: PMC6584330.
Loyd BJ, Kittelson AJ, Forster J, Stackhouse S, Stevens-Lapsley J. Development of a reference chart to monitor postoperative swelling following total knee arthroplasty. Disabil Rehabil. 2020 Jun;42(12):1767-1774. doi: 10.1080/09638288.2018.1534005. Epub 2019 Jan 22. PMID: 30668214.
Image of metal prosthesis from: cortho.org/knee/swelling-after-knee-replacement/