STABILITY 2: Anterior Cruciate Ligament Reconstruction +/- Lateral Tenodesis With Patellar vs Quad Tendon (STABILITY 2)
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ClinicalTrials.gov Identifier: NCT03935750 |
Recruitment Status :
Recruiting
First Posted : May 2, 2019
Last Update Posted : December 21, 2022
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Anterior cruciate ligament (ACL) rupture is one of the most common musculoskeletal injuries in young individuals, particularly those that are active in sports. Up to 30% of individuals under the age of 20 years suffer a re-injury to the reconstructed ACL. Revision ACLR has been associated with degeneration of the articular cartilage and increased rates of meniscal tears, increasing the risk of post-traumatic osteoarthritis (PTOA), additional surgical procedures, reduced physical function and quality of life. As such, strategies to reduce ACLR failure, particularly in young active individuals, are critical to improving short and long-term outcomes after ACL rupture.
There is ongoing debate about the optimal graft choice and reconstructive technique. Three autograft options are commonly used, including the bone-patellar-tendon-bone (BPTB), quadriceps tendon (QT) and hamstring tendon (HT). Additionally, a lateral extra-articular tenodesis (LET) may provide greater stability to the ACLR; however, its effect on failure rate is unclear and surgery-induced lateral compartment OA is a concern.
To definitively inform the choice of autograft and the need for a LET, this multicenter, international randomized clinical trial will randomly assign 1236 young, active patients at high risk of re-injury to undergo ACLR using BPTB or QT autograft with our without LET.
Condition or disease | Intervention/treatment | Phase |
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Anterior Cruciate Ligament Injury Anterior Cruciate Ligament Reconstruction Joint Instability | Procedure: Anterior cruciate ligament reconstruction (ACLR) Procedure: Lateral extra-articular tenodesis (LET) | Not Applicable |

Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 1236 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | This trial will randomly assign 1236 ACL deficient patients at high risk of re-injury to anatomic anterior cruciate ligament reconstruction (ACLR) using bone patellar tendon bone (BPTB) or quadriceps tendon (QT) autograft with or without a lateral extra-articular tenodesis (LET) in a 1:1:1:1 ratio. |
Masking: | Single (Outcomes Assessor) |
Masking Description: | All outcome assessors will be blinded to group allocation. |
Primary Purpose: | Treatment |
Official Title: | Anterior Cruciate Ligament Reconstruction Using Bone Patellar Bone or Quad Tendon Autograft With or Without Lateral Extra-Articular Tenodesis in Individuals Who Are at High Risk of Graft Failure (STABILITY 2) |
Actual Study Start Date : | July 28, 2020 |
Estimated Primary Completion Date : | March 30, 2025 |
Estimated Study Completion Date : | March 30, 2025 |

Arm | Intervention/treatment |
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Experimental: BPTB + LET
Patients will undergo anterior cruciate ligament reconstruction (ACLR) using a bone patellar bone tendon (BPTB) autograft with lateral extra-articular tenodesis (LET).
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Procedure: Anterior cruciate ligament reconstruction (ACLR)
All participants will undergo an anatomic ACLR with either a BPTB or QT autograft, as randomized. Procedure: Lateral extra-articular tenodesis (LET) Participants randomized to the BPTB or QT arms will be randomized a second time to a LET procedure or no additional surgery. |
Active Comparator: BPTB alone
Patients will undergo ACLR using a BPTB autograft without LET.
|
Procedure: Anterior cruciate ligament reconstruction (ACLR)
All participants will undergo an anatomic ACLR with either a BPTB or QT autograft, as randomized. |
Experimental: QT + LET
Patients will undergo ACLR using a quadriceps tendon (QT) autograft with LET.
|
Procedure: Anterior cruciate ligament reconstruction (ACLR)
All participants will undergo an anatomic ACLR with either a BPTB or QT autograft, as randomized. Procedure: Lateral extra-articular tenodesis (LET) Participants randomized to the BPTB or QT arms will be randomized a second time to a LET procedure or no additional surgery. |
Active Comparator: QT alone
Patients will undergo ACLR using a QT autograft without LET.
|
Procedure: Anterior cruciate ligament reconstruction (ACLR)
All participants will undergo an anatomic ACLR with either a BPTB or QT autograft, as randomized. |
- ACL Clinical Failure [ Time Frame: 24 months ]This is a composite endpoint defined as 1) graft rupture or, 2) persistent rotational laxity (asymmetrical positive pivot shift).
- ACL-Quality of Life (QOL) Questionnaire [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]The ACL Quality of Life (QOL) Questionnaire is a patient-reported disease-specific measure of physical symptoms, occupational concerns, recreational activities, lifestyle, social and emotional aspects of ACL injury. Each item has a 0-100 mm visual analogue scale response option (0 represents extremely difficult and 100 not difficult at all). Score is calculated as the average of each item for a total average score out of 100%, where 100% represents the best possible score.
- Knee injury and Osteoarthritis Outcome Score (KOOS) [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]The Knee injury and Osteoarthritic Outcome Score (KOOS) is a patient-reported knee-specific that consists of 42 items in 5 domains (pain, other symptoms, function of daily living, function in sports/recreation and knee-related quality of life). Each domain is scored by summing the responses of the items in the domain standardized to a score from 0 to 100 (worst to best).
- International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]The IKDC-SKF is an 18-item questionnaire that assesses symptoms, function and sports activities. The score is calculated by summing the item responses and normalizing to a scale that ranges from 0 to 100 with 100 representing no symptoms or limitations with function and sports activities.
- Marx Activity Rating Scale [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]The Marx Activity Rating Scale will be used to measure sports activity level. It is a 4-item scale that measures how often patients are able to perform different activities (e.g. running, cutting, decelerating, and pivoting) on a 5-point scale (0 to 4). Scores range from 0 to 16, and higher scores represent higher level of activity.
- Side-to-side difference in knee range of motion [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]Bilateral passive knee extension and active-assisted knee flexion will be measured with a standard goniometer. The side-to-side difference in range of motion will be calculated and interpreted based on the IKDC guidelines (normal: side-to-side difference in knee extension < 3 degrees and side-to-side difference in knee flexion < 5 degrees; nearly normal or worse).
- Isokinetic Quadriceps Strength [ Time Frame: 6, 12 and 24 months ]Bilateral quadriceps strength will be measured using a computerized isokinetic dynamometer (assessing maximal concentric torque at an angular velocity of 90°/s). The ratio of peak torque of the involved to non-involved knee will be calculated.
- Isokinetic Hamstring Strength [ Time Frame: 6, 12 and 24 months ]Bilateral hamstring strength will be measured using a computerized isokinetic dynamometer (assessing maximal concentric torque at an angular velocity of 90°/s) . The ratio of peak torque of the involved to non-involved knee will be calculated.
- Isometric Quadriceps Strength [ Time Frame: 6, 12 and 24 months ]Bilateral quadriceps strength will be measured using hand-held dynamometer (assessing isometric maximal contraction at 90° of knee flexion). The ratio of peak torque of the involved to non-involved knee will be calculated.
- Isometric Hamstring Strength [ Time Frame: 6, 12 and 24 months ]Bilateral hamstring strength will be measured using hand-held dynamometer (assessing isometric maximal contraction at 90° of knee flexion). The ratio of peak torque of the involved to non-involved knee will be calculated.
- Limb Symmetry Index - Hop test [ Time Frame: 6, 12 and 24 months ]Calculated based on the average of four hop tests (single leg hop, 6m timed hop, triple hop, and triple crossover hop). For the single hop for distance, triple hop and triple crossover hop the limb symmetry index (LSI) will calculated as the ratio of the distance hopped on the ACL reconstructed lower extremity to the distance hopped contralateral lower extremity times 100%. For the 6m timed hop, the LSI will be calculated as the ratio of the time to hop 6m on the contralateral normal extremity to the time to hop 6 m on the ACL reconstructed extremity. For analysis, we will use the average of the LSIs for the four hop tests.
- Drop vertical jump (DVJ) testing [ Time Frame: 6 and 12 months ]The drop vertical jump test will be quantified using a Microsoft Kinect V2 sensor and ACL Gold software to measure dynamic knee valgus that will be defined as the ratio of the distance between the knees to the distance between the ankles. The average ratio of the distance between the knees to ankles across 3 trials will be calculated and use for analysis.
- Donor site morbidity - Sensory Disturbance [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]Sensory disturbance will be assessed via light touch to regions around the graft skin incision and anterolateral tibia. It will be rated as absent, mild, moderate or severe. This outcome will be presented as the proportion of individuals in each category.
- Donor site morbidity - Anterior Kneeling Pain [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]Anterior kneeling pain measured using an 11-point numeric rating scale (0 - no pain; 10 - worst imaginable).
- Adverse events [ Time Frame: 24 months (at 1.5, 3, 6, 12 and 24 months) ]Defined as any new event not present during the pre-intervention period or an event present pre-intervention that has increased in severity.

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Ages Eligible for Study: | 14 Years to 25 Years (Child, Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Age 14-25,
- An ACL-deficient knee,
- Skeletal maturity (i.e. closed epiphyseal growth plates on standard knee radiographs),
- At least two of the following: participate in a competitive pivoting sport; have a pivot shift of grade 2 or greater; have generalized ligamentous laxity (Beighton score of ≥4) and/or genu recurvatum >10 degrees.
Exclusion Criteria:
- Previous ACLR on either knee,
- Partial ACL injury (defined as one bundle ACL tear requiring reconstruction/augmentation of the torn bundle with no surgery required for the intact bundle),
- Multiple ligament injury (two or more ligaments requiring surgery),
- Symptomatic articular cartilage defect requiring treatment other than debridement,
- >3 degrees of asymmetric varus,
- Inflammatory arthropathy,
- Inability to provide consent,
- Pregnancy at baseline.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03935750
Contact: Stacey Wanlin | 519-661-2111 ext 82705 | swanlin@uwo.ca |

Principal Investigator: | James J Irrgang, PT PhD FAPTA | University of Pittsburgh | |
Principal Investigator: | Alan Getgood, MD FRCS | Fowler Kennedy Sport Medicine Clinic, Western University, Department of Surgery | |
Principal Investigator: | Volker Musahl, MD | University of Pittsburgh | |
Principal Investigator: | Dianne M Bryant, PhD | Western University, School of Physical Therapy & Department of Surgery |
Documents provided by James J. Irrgang, University of Pittsburgh:
Responsible Party: | James J. Irrgang, Professor, University of Pittsburgh |
ClinicalTrials.gov Identifier: | NCT03935750 |
Other Study ID Numbers: |
STUDY20110331 U01AR076144 ( U.S. NIH Grant/Contract ) |
First Posted: | May 2, 2019 Key Record Dates |
Last Update Posted: | December 21, 2022 |
Last Verified: | December 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | A public-use version of the dataset will be constructed by the Data Coordinating Center (DCC) with contents to be determined jointly by the study PIs and the DCC Director. Copies of the public-use version of the dataset will be housed at the DCC on the DA secure server along with suitable documentation of this dataset. The public-use version of the dataset will be exported by CRF in one or more files in simple, widely-accessible formats, e.g., .xls, .csv, and/or SAS datasets. Documentation will be in .pdf files. |
Supporting Materials: |
Study Protocol |
Time Frame: | The public-use version of the database will be made available two years after the study's main paper is published. |
Access Criteria: | Outside investigators wishing to conduct analyses using the data will submit a request with objectives, methods, and analysis plan to the PI and the Director of the DCC. Once the request is approved, the public-use version of the dataset, with documentation, will be sent by secure email using e-mail, ftp, or other mutually agreeable transmission method. |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Lateral extra-articular tenodesis Autografting Allografting Bone-Patellar Tendon-Bone Grafting |
Joint Instability Anterior Cruciate Ligament Injuries Knee Injuries Leg Injuries |
Wounds and Injuries Joint Diseases Musculoskeletal Diseases |