A knee replacement is major surgery, and you should expect some pain afterwards. Pain control has improved a great deal in recent years. Anaesthetists and surgeons now combine several techniques and medicines, an approach called multimodal analgesia, so that each one does part of the work.[1] The aim in the first weeks is not to remove pain completely but to bring it down to a level where you can walk and do your exercises. Pain then eases gradually over the following months.
At a Glance
- Some pain is normal after a knee replacement, and how much differs from person to person.
- Several medicines and techniques are combined to keep pain at a manageable level.
- Regular icing and keeping your activity modest in the early weeks help control swelling and pain.
- Most improvement comes in the first 3 to 4 months, but the knee can take up to 12 months to fully settle.
On this page
How much does a knee replacement hurt, and how long does the pain last?
How is pain controlled during the operation?
What pain relief will you take after surgery?
Why is icing so important after a knee replacement?
Why does doing less in the first 8 weeks help with pain?
How much does a knee replacement hurt, and how long does the pain last?
Pain is usually at its worst in the first few days and weeks after surgery, then falls steadily. On average, knee pain drops by more than half by 3 months, and by 12 months it is about a quarter of what it was before surgery.[2]
Most of your recovery comes in the first 3 to 4 months, but it can take up to 12 months for the knee to fully settle. Pain is also individual, and two people having the same operation can have quite different experiences.
Even the same person can recover differently from each knee. If you have both knees replaced at different times, the second recovery is often easier in Dr Vishal Pai’s experience, because you know what to expect and are more mentally prepared. That is not true for everyone, and some people find the second knee more sore in the first day or two.[3] For a stage-by-stage guide to getting back to normal, see the knee replacement recovery timeline.
How is pain controlled during the operation?
Pain control starts before the operation begins. Dr Vishal Pai’s anaesthetist usually combines a general anaesthetic with a spinal anaesthetic (an injection in the lower back that numbs the legs). The anaesthetist also gives two nerve blocks. An adductor canal block numbs the nerves to the front and inner side of the knee while largely sparing the thigh muscle, so you can still stand and walk. An IPACK block numbs the small nerves at the back of the knee. The anaesthetist decides on the best combination for you and will talk it through with you beforehand.
During the operation, Dr Vishal Pai also injects a mix of local anaesthetic, a small dose of morphine, adrenaline and a corticosteroid into the tissues around the joint, including the back of the knee. This is called periarticular infiltration. Combining a nerve block with this infiltration lowers pain over the first one to two days compared with infiltration alone.[4] Adding a corticosteroid to the mix can reduce pain and help early movement in the first couple of days, although the size of that benefit is uncertain.[5,6]
What pain relief will you take after surgery?
Pain relief works best when several medicines are combined and taken on a schedule, rather than waiting for the pain to build. Dr Vishal Pai’s usual plan includes:
- Paracetamol and an anti-inflammatory, taken regularly for the first 2 weeks.
- A slow-release opioid for the first few days, usually stopped about a week after surgery.
- A short-acting opioid, taken only when needed for stronger pain.
- A 4-day course of an oral corticosteroid, starting the day after surgery, to reduce inflammation and swelling.
- Duloxetine for 14 days, a medicine also used for nerve-related pain.
An oral corticosteroid in the first days after surgery lowers pain.[7] Duloxetine reduces pain and the need for opioids by a small amount, and its main side effect is drowsiness.[8]
Most people need strong pain relief for 4 to 6 weeks. As you improve, the opioid is stopped first, then the other medicines. Your plan is tailored to your health and any other medicines you take, so not everyone receives every medicine on this list.
Why is icing so important after a knee replacement?
Icing is one of the most useful things you can do for your own pain, and it is entirely in your hands. Swelling drives much of the early pain after a knee replacement, and cold reduces blood flow and swelling around the joint. Cooling the knee eases pain and swelling in the first days after surgery.[9]
Dr Vishal Pai recommends this routine:
- Ice for 20 minutes in every hour while you are awake.
- Raise your leg while you ice, so your heel sits above the level of your heart.
- Put pillows under your heel, never under your knee, so the knee does not stiffen in a bent position.
- Keep icing regularly for at least 8 weeks.
A cold-compression device makes this routine easier to keep up over several weeks, but ice packs also work. Always protect your skin with a cloth and keep to the time limit, as cold left on too long can injure the skin.
Why does doing less in the first 8 weeks help with pain?
Surgery triggers an inflammatory response in the knee, and doing too much too soon makes swelling and pain worse. Walking more in the early weeks does not speed up your recovery. It inflames the knee and can set you back.
For this reason, Dr Vishal Pai asks patients to keep to a daily step limit for the first 6 weeks:
| Week 1 | Week 2 | Week 3 | Week 4 | Week 5 | Week 6 |
|---|---|---|---|---|---|
| 750 | 1,250 | 2,000 | 2,750 | 3,500 | 4,250 |
These are upper limits, not targets, and a phone or watch makes them easy to track. From week 7, you can increase your steps as comfort and swelling allow.
In the first 8 weeks the focus is on short walks and bending and straightening exercises. Strength training comes later, once the inflammation has settled. If your knee is more swollen, hotter or more painful the next morning, you did too much the day before, so ease back for a day or two. This is Dr Vishal Pai’s approach rather than a universal rule, and your physiotherapist will guide the details.
Why is sleep difficult after a knee replacement?
Broken sleep is one of the least expected parts of recovery. Sleep is usually at its worst in the first 6 weeks and then improves, and by a year sleep is, on average, better than it was before surgery.[10] In Dr Vishal Pai’s experience, it is not unusual for sleep to be disturbed for up to 4 months.
Pain is one reason, but not the only one. A sensitive scar and difficulty finding a comfortable position in bed also play a part. Poor sleep in the early months is common, it is not a sign that anything is wrong, and it does settle.
Summary
There is some discomfort after a knee replacement, but it can be managed. Several approaches work together: anaesthetic techniques and nerve blocks on the day, a combination of medicines afterwards, regular icing, and keeping your activity modest while the knee settles. The goal of the first few weeks is not to remove pain completely but to keep it at a level where you can do your rehabilitation exercises. Pain eases gradually, with most of the gains in the first 3 to 4 months, although it can take up to 12 months to fully recover.
References
Show all 10 referencesHide references
- Lavand’homme P et al. 2022. Pain management after total knee arthroplasty: PROSPECT recommendations. European Journal of Anaesthesiology.
- Sayah S et al. 2021. Clinical course of pain and function following total knee arthroplasty: a systematic review and meta-regression. The Journal of Arthroplasty.
- Sun JY et al. 2015. Analysis of early postoperative pain in the first and second knee in staged bilateral total knee arthroplasty: a retrospective controlled study. PLoS ONE.
- Topalidou X et al. 2026. Comparative efficacy of adductor canal block in total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials. A&A Practice.
- Li Z et al. 2021. The efficacy and safety of glucocorticoid on periarticular infiltration analgesia in total knee arthroplasty: a systematic review and meta-analysis of randomized controlled trials. The Journal of Arthroplasty.
- Huang LY et al. 2021. Should corticosteroids be administered for local infiltration analgesia in knee arthroplasty? A meta-analysis and systematic review. Journal of Clinical Pharmacy and Therapeutics.
- Shaw JH et al. 2023. Oral dexamethasone following total knee arthroplasty: a double-blind, randomized controlled trial. The Journal of Arthroplasty.
- Ibrahim A et al. 2026. Duloxetine for postoperative pain management in total hip and knee arthroplasty: a systematic review and meta-analysis. Journal of Orthopaedic Surgery and Research.
- Aggarwal A et al. 2025. Cryotherapy following total knee replacement. Cochrane Database of Systematic Reviews.
- Mehta N et al. 2024. Sleep quality improves post total knee arthroplasty: addressing early disturbance and risk factors. Journal of ISAKOS.
Frequently Asked Questions
How painful is a knee replacement on a scale of 1 to 10?
It varies a lot from person to person. Two days after surgery, average pain is roughly 3 to 5 out of 10, and lower in people whose knee is cooled regularly.[9] Pain is usually worse when you move and exercise than at rest, and it falls steadily over the following weeks.
When should I contact the rooms about pain?
Call the rooms if your pain suddenly gets much worse, or if you notice increasing swelling, redness or warmth around the wound, a temperature over 38°C that does not settle with paracetamol, wound ooze that has not stopped 3 days after surgery, new calf pain or swelling, or a knee that suddenly will not bend as well. Sudden chest pain or shortness of breath is an emergency, so call 000 or go to your nearest emergency department.
How long will my knee stay swollen and warm?
Some swelling and warmth is normal for months and is not a sign that anything has gone wrong. It usually lasts 3 to 6 months, and most people still have some swelling at their 4-month review. Icing, raising the leg and pacing your activity all help it settle.
How can I sleep better after a knee replacement?
Take your pain relief 30 to 60 minutes before bed rather than waiting for the knee to wake you, and ice and elevate the knee before you get into bed. Support the leg with a pillow under your heel, not under your knee, and keep daytime naps short. If you are getting almost no sleep, call the rooms, as it is usually a pain-control problem that can be helped.
Want to know how pain would be managed for your knee?
Dr Vishal Pai performs knee replacement surgery in Melbourne. A consultation is a chance to talk through how pain is controlled before, during and after surgery, and what may suit your circumstances.
Written by Dr Vishal Pai
Vishal is an experienced knee surgeon based in Bayside, Melbourne. He consults at Sandringham Orthopaedic Specialists and operates at The Avenue Hospital and Calvary Holmesglen Private Hospital. His practice focuses on sports knee surgery, including ACL reconstruction and meniscal repair, as well as robotic knee replacement.