Knee extension loss after ACL reconstruction

Investigating the Knee Extension Deficit on Knee Strength Recovery Following an Anterior Cruciate Ligament Reconstruction

Not applicable Interventional Hacettepe University · NCT06863610

We will see if people 18–45 who had ACL reconstruction with a hamstring graft and more than 5° loss of knee extension early after surgery have worse knee extensor strength and function than similar patients without that deficit.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment30 (estimated)
Ages18 Years to 45 Years
SexAll
SponsorHacettepe University Academic / other
Locations1 site (Ankara)
Trial IDNCT06863610 on ClinicalTrials.gov

What this trial studies

This study compares two groups of ACL-reconstructed patients based on whether they have an early postoperative knee extension deficit greater than 5° or not. All participants had hamstring tendon autografts and completed a standardized rehabilitation program. Researchers will measure knee extensor muscle strength and knee function outcomes and compare recovery between the groups. The goal is to determine whether an early extension deficit predicts poorer strength recovery and functional results.

Who should consider this trial

Good fit: Adults aged 18–45 who had primary ACL reconstruction with a hamstring tendon autograft after a non-contact injury, had a pre-injury Tegner score >5, and attended the prescribed rehabilitation program are ideal candidates.

Not a fit: Patients who had patellar tendon grafts or allografts, revision surgery, additional meniscus or cartilage repairs, prior lower-limb injuries, systemic or neurological conditions, or who will not complete the required evaluations are unlikely to benefit from these findings.

Why it matters

Potential benefit: If successful, the results could help clinicians identify patients at risk for poor quadriceps recovery so they can target rehabilitation earlier and more precisely.

How similar studies have performed: Previous observational work links extension loss to quadriceps weakness and later osteoarthritis, but using an early >5° extension deficit to predict strength recovery has not been well established.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients who underwent ACL repair using hamstring tendon autograft
* volunteered to participate in the study between the ages of 18-45
* a non-contact injury mechanism
* a Tegner Activity Score \>5 before the injury
* regularly attended the rehabilitation program after surgery (not missing more than three sessions)

Exclusion Criteria:

* Patients who underwent ACL repair with patellar tendon autograft or allograft, revision surgery
* underwent meniscus and or cartilage repair in addition to ACL repair
* a history of previous knee, ankle, or groin injuries
* concomitant systemic and/or neurological pathologies
* a history of injury to the contralateral lower extremity
* do not want to participate in the evaluations that should be done before the study.

Where this trial is running

Ankara

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Anterior Cruciate Ligament InjuriesACLreconstructionkneeextension deficit
Last reviewed 2026-06-09 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.