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How to Sleep After a Knee Replacement: 2 Best Positions

by Dale Cudmore | Updated: Feb 17, 2022

Sleep trouble after any type of major surgery is a common complaint.

And while some sleep problems are expected, they shouldn’t last for months on end. In fact, research has shown that poor sleep after knee surgery slows down recovery.

There’s no perfect solution for everyone, but sleep problems can be somewhat mitigated by sleeping in the right positions, medication, and preventative measures (if possible).

How Common Are Sleep Problems After Knee Replacement?

Research has shown that there’s a significant change in sleep structure after knee surgery. REM sleep decreases 93% on the first night after, but then returns to normal within a week (by the fourth night for most people) (1).

During that period, it’s normal for subjective sleep quality to feel lower.

However, sleep problems often persist for recovering patients.

A study of 105 patients who underwent either total hip or knee replacement found that (2):

In the early postoperative period (4-5 weeks), patients reported significant increases in sleep disturbance as denoted by increased length of time to fall asleep and mean nightly awakenings compared with the preoperative baseline. 

So it’s quite common to have some sleep issues during the first month of recovery.

However, the study also found that the average sleep quality improved past the baseline at the 40 week (about 10 month) follow-up.

SummaryMany patients experience sleep trouble after a knee surgery. They are usually the worst for the first month, and then improve as the knee continues to recover.

Sleep Disruptions After Knee Surgery Predict Overall Recovery Time

Aside from not feeling well because of poor sleep, it turns out that it’s vital for recovery as well.

One research team found that the level of sleep problems 1 month after the surgery predicts functional limitations (i.e. knee health) 3 months following surgery (3).

In other words, if someone recovering is experiencing poor sleep, it’s not something that should be left to improve on its own.

How to Improve Sleep Quality After a Knee Replacement

There are a few main ways that sleep quality can be improved for someone in this context:

  • Traditional sleep therapies - Cognitive behavioral therapy (CBT) is often effective as improving sleep quality, however, it does take time to work. Unless CBT is started at least a few weeks before the surgery, it’s likely not the best option.
  • Medication - Medication can be used for both pain management and sleep quality (some medications already do both). They do come with side effects, but research has shown that medication like zolpidem improves sleep quality and knee recovery after surgery (4).
  • Sleep positions - Most sleep issues after knee surgery come from discomfort and pain. Some sleeping positions put more stress on the injured knee than others, and are more likely to cause sleep disturbances.

Medication will obviously be handled by a patient’s doctor, but it’s important to give clear feedback to the doctor if it’s not helping, so a different medication can be tried.

The Best Sleep Positions To Minimize Knee Pain

The 2 best positions for sleeping while minimizing knee stress are:

  • Flat on your back with legs straight out - This position ensures that the knee is minimally rotated and not in flexion. A thin pillow should be placed under the knee and calf region to give the leg a slight bend.
  • On your side with the recovering knee on top and legs slightly bent - Side sleeping is generally most preferred by people. A pillow should be placed between the knees in order to prevent the injured knee on top from rotating inwards.

Conversely, the worst position is to sleep on your front, where there will be direct pressure on your knee.

If someone is having trouble initially getting to sleep because of discomfort, it may help to ice the affected knee for 10-20 minutes before going to sleep to dull the pain.


  1. Sleep disturbances after fast-track hip and knee arthroplasty
  2. Prospective Assessment of Sleep Quality Before and After Primary Total Joint Replacement
  3. Sleep Disruptions Mediate the Relationship Between Early Postoperative Pain and Later Functioning Following Total Knee Replacement Surgery
  4. Sleep Quality Effects Recovery After Total Knee Arthroplasty (TKA)

Medical Disclaimer: The information on is not intended to be a substitute for physician or other qualified care. We simply aim to inform people struggling with sleep issues about the nature of their condition and/or prescribed treatment.

About the authorDale is the founder of Snooze University and a sleep researcher. I overcame my sleep issues and now I'd like to help you do the same by summarizing the latest sleep studies for you.