For Patients | Knee Replacement

Study Activities

What to Expect


  • At three time points (pre-surgery, 6-weeks post-surgery, and 3-months post-surgery) there are a series of surveys to complete. These surveys take about 1 – 1.5 hours.
  • Many of these surveys can be completed at home, remotely, if that is an option for you. You will get a link to complete the surveys, prior to the in-person visits. If you can’t complete them ahead of time, you can complete them at the visit.
  • In addition, we will send you brief surveys to complete just prior to your surgery and daily for 4 weeks after surgery.
  • While there will be no in-person study visit at 6 months, there will be a set of surveys to complete from home (about 30 min), and a 12 month brief follow-up survey (5 min).

Functional Testing:

  • For study visits 1 and 3, you will do two timed tests:
    • A walking test of 10 meters, about 30 feet.
    • A stand-up and sit-down test, 5 times in a row from a chair.
  • You will rate your pain before and after each test.

Sensory Testing:

  • For study visits 1 and 3, we will assess your pain sensitivity.
  • Pressure Testing: Pain thresholds with a small pressure device will be assessed 3 times at your knee and your shoulder.
  • Repeated Poke Test: Using a plastic filament (thickness of a paperclip), you will rate any pain that occurs initially and after we tap 10 times at two different sites, your knee, and your shoulder.
  • Cold water test: You will place one hand in a bucket of very cold water. After a minute, the pressure testing will be repeated at your shoulder.

Blood Draw:

  • For study visits 1, 2, and 3 blood samples will be collected (3 tubes).
  • Snacks will be provided after the study visit.


  • For study visits 1 and 3, you will have an MRI to image your brain.
  • You must remain still during portions of this test. It will take about 60 minutes.
  • Please wear comfortable, loose fitting clothing with no zippers or metal buttons. (Women wear a sports bra, if able, and no under-wire bras) If unable, there will gowns available for use.
  • A pressure cuff, like a blood pressure cuff, will be applied to your calf and partially inflated to induce some pressure pain for 6 minutes during the imaging.

Note: Not all study participants will be selected to complete Visit 3.