Causes of painful knee scarring after ACL injury or surgery

Cellular origins and molecular mechanisms of arthrofibrosis

NIH-funded research University of Southern California · NIH-11327336

Researchers will look at the cells and signals that cause too much scar tissue in knees after ACL injury or reconstruction to help people with painful, stiff joints.

Quick facts

Grant typeR01 grant
Study typeNIH-funded research
Funding institutionUniversity of Southern California NIH-funded
Lab location1 site (Los Angeles, UNITED STATES)
Project IDNIH-11327336 on NIH RePORTER

What this research studies

This project studies why some people develop arthrofibrosis (excess scar tissue and painful stiffness) after ACL injury or knee surgery by tracing how inflammation turns specific progenitor cells into scar-producing cells. Scientists will analyze patient-derived tissues and use laboratory models to map the cellular types and molecular signals involved, including IL-6/gp130-related pathways and genes like ARG2. They will perform experiments to see if interrupting those molecular steps can reduce fibrotic cell activity and excess collagen deposition in the joint. The overall aim is to identify targets that could be used to develop non-surgical treatments to prevent or lessen painful knee stiffness.

Who could benefit from this research

Good fit: Ideal candidates would be people who have had an ACL injury or ACL reconstruction and are at risk of, or are experiencing, persistent knee stiffness and scar-related pain.

Not a fit: People whose knee pain is due to other causes (for example primary osteoarthritis without post-injury scarring) or those seeking immediate clinical treatment may not directly benefit from this largely basic-science work.

Why it matters

Potential benefit: If successful, this work could lead to non-surgical treatments that prevent or reduce post-surgical knee scarring and chronic stiffness.

How similar studies have performed: Anti-fibrotic strategies have shown promise in other organs and in early lab studies, but targeted, proven therapies for arthrofibrosis after ACL surgery are not yet established.

Where this research is happening

Los Angeles, UNITED STATES

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Conditions ACL injury
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.