Recruiting young active ACL-deficient patients at high risk of ACL re-injury


Anterior cruciate ligament (ACL) reconstruction surgery has unacceptably high failure rates in young active individuals. ACL graft choice and/or augmentation with a lateral extra-articular tenodesis (LET) has the potential to reduce failure rates in this patient population.
This international, multicentre randomized clinical trial will determine if ACLR using a patient’s own quadriceps tendon or patellar tendon, either with or without a LET, reduces the risk of ACL failure, results in less symptoms, better function and quality of life, and an improved ability to return to sports. It is anticipated that 1,236 people will participate from research sites in Canada, the United States, Germany, Norway, the United Kingdom and Sweden.


Currently recruiting participants: Yes

Eligible gender: Male, Female, Transgender, Other

Eligible ages: 14 to 25

Accepts healthy participants: Yes

Inclusion criteria:

Patients meeting the following INCLUSION CRITERIA may be eligible for the study:
1) ACL-deficient knee
2) Ages 14 – 25 years
3) Skeletally mature
4) Two of the following:
- Competes in a competitive pivoting sport
- Has generalized ligamentous laxity (> 4 Beighton score)
- Grade 2 pivot shift
- Genu recurvatum of >10 degrees

Exclusion criteria:

Patients with the following EXCLUSION CRITERIA are not eligible for the study:
1) Previous ACL reconstruction of either knee
2) Multiple ligament injury (ie: PCL, collaterals) requiring repair / reconstruction
3) Symptomatic articular cartilage defect
4) Inflammatory arthritis, metabolic bone, collagen, crystalline, degenerative joint or neoplastic disease
5) Femoral, tibial or patellar fracture (other than Segond fractures)
6) Asymmetric valgus or varus > 3 degrees
7) Debilitating anterior knee pain, patellar or quadriceps tendon tendonitis


Fill out the following form if you want to participate in this research

Method of contact

Additional information

Contact information

Prospective participants can contact the STABILITY 2 Study Research Coordinator for additional information.

Principal investigator:

Alexander Rezansoff

Clinical trial: