Brain may 'forget' to use healed leg after ACL surgery
NCT ID NCT04837417
First seen Jun 26, 2026 · Last updated Jun 27, 2026 · Updated 1 time
Summary
This study looked at 10 people who had ACL knee surgery 6-18 months earlier. Researchers tested whether the brain unconsciously stops fully activating the quadriceps muscle on the injured side, a phenomenon called 'learned non-use.' They used electrical stimulation, balance tests, and brain magnetic stimulation to measure nerve and muscle activity. The goal was to understand why weakness persists even after healing, which could improve return-to-sport decisions.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
- What this could lead to
- If successful, this study could help identify better criteria for when it's safe to return to sports after ACL surgery, and point toward new rehab strategies.
- What could go wrong
- This is a very small, completed observational study with only 10 participants. Results may not apply to everyone and do not test any treatment.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for ANTERIOR CRUCIATE LIGAMENT INJURIES are added.
By submitting, you agree to our Terms of use
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
ASST Centro Specialistico Ortopedico Traumatologico Gaetano Pini-CTO, Presidio Ospedaliero Gaetano Pini
Milan, Italy
-
Istituto Auxologico Italiano
Milan, MI, 20121, Italy
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- Can a 3D-Printed gadget speed up knee recovery?
- Saving the ligament: a trial tests whether repairing a torn ACL beats replacing it
- Which tendon graft helps female athletes recover best after ACL surgery?
- Nerve block showdown: which technique eases ACL surgery pain best?
- Which ACL graft gets young athletes back in the game faster?
- Vibration therapy may reduce second ACL injury risk