ACL ReconstructionLETOTTNCT07049484
Clinical and Biomechanical Outcomes of Anterior Cruciate Ligament (ACL) Reconstruction Associated With Lateral Extra-articular Tenodesis (LET)
An observational study of ACL Reconstruction and Tenodesis, run by Stefano Zaffagnini at 1 site in Italy.
Trial summary
The anterior cruciate ligament (ACL) is one of the main stabilizers of the knee joint, and its injury is among the most common soft tissue injuries of the knee. Several surgical reconstruction techniques are available, utilizing various tissues as a graft for the neo-ligament, including both autografts and allografts. Read more about this study
- Who is it for?
- Ages 18 to 50 years
- Conditions the study is for
- ACL Reconstruction, Tenodesis, ACL Injuries
- How many people
- 51 participants
- Where
- 1 siteItaly
- Study dates
- 24 Mar 2026to Jun 2029
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 50 years
- All sexes
- No healthy volunteers
- Adult
Study population: Patients will be recruited from those surgically treated at the Second Clinic of the Rizzoli Orthopaedic Institute, undergoing anterior cruciate ligament reconstruction using the "over-the-top" single-bundle technique with gracilis and semitendinosus tendons, combined with lateral extra-articular tenodesis (LET). Only patients with at least 6 months of follow-up after the surgery date will be enrolled. Subsequently, patients will be re-evaluated during a 12-month follow-up visit, as per standard clinical practice for this procedure.
Who may be able to join
- Patients undergoing isolated ACL reconstruction using gracilis and semitendinosus tendons with the over-the-top technique and LET.
- Both male and female patients.
- Patients who have given consent to participate in the study.
- Age between 18 and 50 years at the time of surgery.
Who cannot join
- Previous surgery on the same limb (meniscectomy, prior ACL reconstruction, displaced fractures).
- Surgical technique different from Over-the-Top with LET using autologous gracilis and semitendinosus tendons.
- Other concomitant ligament injuries requiring surgical treatment.
- Patients undergoing additional procedures at the same time as ACL reconstruction and LET (e.g., concomitant osteotomy, meniscus transplant, cartilage procedure…).
- Patients who did not provide informed consent.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Italy1 site, 1 recruiting
- Recruiting
IRCCS Istituto Ortopedico Rizzoli
Bologna, 40136
Stefano Zaffagnini, 0516366075, stefano.zaffagnini@ior.it
About this study
Official title: Clinical and Biomechanical Outcomes of Anterior Cruciate Ligament (ACL) Reconstruction Associated With Lateral Extra-articular Tenodesis (LET): a Short-term Prospective Arthrometric Study
The anterior cruciate ligament (ACL) is one of the main stabilizers of the knee joint, and its injury is among the most common soft tissue injuries of the knee. Several surgical reconstruction techniques are available, utilizing various tissues as a graft for the neo-ligament, including both autografts and allografts.
The "Over-the-top single-bundle technique with gracilis and semitendinosus tendons combined with lateral extra-articular tenodesis (LET)" was developed in 1998 by Prof. Marcacci and Prof. Zaffagnini, and it is still the preferred method for ACL reconstruction at the Second Clinic of the Rizzoli Orthopaedic Institute.
Read more
Cadaveric biomechanical studies have shown that combining LET with ACL reconstruction improves knee joint stability in both the anteroposterior and rotational planes. However, a recent in vivo study has challenged this hypothesis, showing that in patients undergoing surgery, the addition of LET enhances knee stability only in the anteroposterior direction and only for a limited period of six months. At twelve months postoperatively, joint laxity appeared similar to that of patients who did not undergo the additional procedure. Furthermore, the same study did not assess rotational instability using the pivot-shift test, an essential parameter as it is closely linked to knee stability and the patient's subjective perception of surgical success.
Despite the increasing use of LET in conjunction with ACL reconstruction, few studies have analyzed the short-term postoperative effects of lateral extra-articular tenodesis and its potential benefits during the early stages of rehabilitation and return to sport.
This study was conceived in response to this clinical question, with the goal of evaluating anteroposterior and rotational laxity in a group of patients who underwent ACL reconstruction combined with LET, in order to analyze clinical outcomes and, most importantly, any changes in stability during the early postoperative period.
The results aim to improve understanding of knee stability in the initial phase following surgery, providing valuable information for rehabilitation teams to optimize recovery protocols and more effectively guide return-to-sport decisions for patients undergoing both procedures.
- Conditions
- ACL Reconstruction, Tenodesis, ACL Injuries
- Medical subject headings
- Anterior Cruciate Ligament Injuries
What is being measured
The primary outcome is the main question the study is designed to answer.
KYRA accelerometer
KYRA is a non-invasive outpatient device that allows the assessment of dynamic laxity during the pivot shift phenomenon. The device enables highly precise quantification of the degree of laxity. The unit of measurement is millimeters per second squared.
Measured: 12 months
Secondary outcomes (10)
KT-1000 Arthrometer
The KT-1000 is an objective assessment tool that measures anterior tibial translation relative to the position of the femur by applying a predefined force that pushes the tibia forward. It is commonly used in research settings to quantitatively evaluate static anteroposterior knee laxity following anterior cruciate ligament reconstruction surgeries.
Measured: 12 months
Physical Examination
A standard physical examination will be performed, including palpation, assessment of joint mobility, and laxity. During palpation, the typical tender points related to meniscal pathology are examined: the joint line areas on their anterior, middle, and posterior aspects. Pain is recorded as either present or absent. Joint mobility is assessed by asking the patient to flex and extend the knee, measuring the angle formed in degrees (0-130), with attention to the presence or absence of any joint clicks or catches. Laxity is evaluated using the classic tests: anterior drawer test, Lachman test, and pivot shift test.
Measured: 12 months
Anterior Drawer Test
This test allows evaluation of the anterior translation of the tibia relative to the femur with the knee flexed at 90 degrees. An increased translation suggests a lesion of the reconstructed ACL (neo-ACL). The degree of translation is quantified on a scale from 0 to 3.
Measured: 12 months
Lachman Test
This test allows evaluation of the anterior translation of the tibia relative to the femur with the knee flexed at 30 degrees. An increased translation suggests a lesion of the reconstructed ACL (neo-ACL). It is quantified on a scale from 0 to 3.
Measured: 12 months
Pivot Shift Test
This is a clinical maneuver used to assess rotational instability of the knee under examination. The test is performed by applying an internal rotation, valgus stress, and knee flexion; the occurrence of a tibial "clunk" or shift suggests a lesion of the reconstructed ACL (neo-ACL) associated with rotational instability. It is quantified on a scale from 0 to 3.
Measured: 12 months
Knee Injury and Osteoarthritis Outcome Score (KOOS)
The Knee Injury and Osteoarthritis Outcome Score (KOOS) is a self-administered questionnaire used to evaluate both short- and long-term outcomes after a knee injury. It assesses five dimensions: pain, symptoms, activities of daily living, sports and recreational function, and knee-related quality of life.
Each dimension is scored separately using a 5-point Likert scale ranging from 0 (no problems) to 4 (extreme problems). Scores for each dimension are summed and then transformed to a 0-100 scale, where 0 represents extreme knee problems and 100 indicates no knee problems. The KOOS meets essential standards for outcome measures and is useful for monitoring the progression of knee injuries and the effectiveness of treatments.
Measured: 12 months
Lysholm Knee Score
The Lysholm Knee Score is a validated measurement scale that evaluates knee function through 8 items, allowing assessment of the knee's condition in relation to the functional demands of daily activities. This assessment tool is used to evaluate surgical outcomes in patients operated on for ligament or meniscal injuries of the knee. The final score is obtained by summing the scores from the different items and ranges from 0 to 100. Scores are categorized into subgroups: Excellent (95-100), Good (84-94), Fair (65-83), and Poor (<64).
Measured: 12 months
VAS (Visual Analog Scale)
The VAS is a unidimensional quantitative numerical scale for pain assessment ranging from 0 to 10. The patient selects the number that best describes the intensity of their pain at that moment. A score of 0 means no pain, and 10 indicates the worst possible pain.
Measured: 12 months
Tegner Score
The Tegner Score estimates a person's level of physical activity on a scale from 0 to 10, where 0 represents "disability" and 10 represents participation in competitive sports, such as national or international-level soccer. This score is the most widely used to define the physical activity level of patients with knee disorders. In the study, the Tegner Score will be completed directly by the examiner through an interview with the patient.
Measured: 12 months
Complications or Subsequent Interventions
Any complications and subsequent interventions will be documented and recorded in the Case Report Form (CRF). The staff responsible for distributing and collecting the questionnaires will assign an identification code on the questionnaire cover page to protect the privacy of the study participants.
Measured: 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Jul 2025
- Study start24 Mar 2026
- Primary completionJun 2028 (estimated)
- Study completionJun 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ACL ReconstructionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 51 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Stefano Zaffagnini
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Stefano Zaffagnini, Istituto Ortopedico Rizzoli
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07049484
- Sponsor's protocol ID
- LETOTT
- Acronym
- LETOTT
- Status last verified
- Apr 2026
- First submitted
- 25 Jun 2025
- Last updated
- 22 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 22 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Clinical and Biomechanical Outcomes of Anterior Cruciate Ligament (ACL) Reconstruction Associated With Lateral Extra-articular Tenodesis (LET): a Short-term Prospective Arthrometric Study
- ClinicalTrials.gov ID
- NCT07049484
- Acronym / sponsor ID
- LETOTT / LETOTT
- Conditions
- ACL Reconstruction, Tenodesis, ACL Injuries
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 51 participants (estimated)
- Lead sponsor
- Stefano ZaffagniniUniversity, hospital or other
- Study start
- 24 Mar 2026 (actual)
- Primary completion
- Jun 2028 (estimated)
- Study completion
- Jun 2029 (estimated)
- First posted
- 3 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The anterior cruciate ligament (ACL) is one of the main stabilizers of the knee joint, and its injury is among the most common soft tissue injuries of the knee. Several surgical reconstruction techniques are available, utilizing various tissues as a graft for the neo-ligament, including both autografts and allografts.
The "Over-the-top single-bundle technique with gracilis and semitendinosus tendons combined with lateral extra-articular tenodesis (LET)" was developed in 1998 by Prof. Marcacci and Prof. Zaffagnini, and it is still the preferred method for ACL reconstruction at the Second Clinic of the Rizzoli Orthopaedic Institute.
Cadaveric biomechanical studies have shown that combining LET with ACL reconstruction improves knee joint stability in both the anteroposterior and rotational planes. However, a recent in vivo study has challenged this hypothesis, showing that in patients undergoing surgery, the addition of LET enhances knee stability only in the anteroposterior direction and only for a limited period of six months. At twelve months postoperatively, joint laxity appeared similar to that of patients who did not undergo the additional procedure. Furthermore, the same study did not assess rotational instability using the pivot-shift test, an essential parameter as it is closely linked to knee stability and the patient's subjective perception of surgical success.
Despite the increasing use of LET in conjunction with ACL reconstruction, few studies have analyzed the short-term postoperative effects of lateral extra-articular tenodesis and its potential benefits during the early stages of rehabilitation and return to sport.
This study was conceived in response to this clinical question, with the goal of evaluating anteroposterior and rotational laxity in a group of patients who underwent ACL reconstruction combined with LET, in order to analyze clinical outcomes and, most importantly, any changes in stability during the early postoperative period.
The results aim to improve understanding of knee stability in the initial phase following surgery, providing valuable information for rehabilitation teams to optimize recovery protocols and more effectively guide return-to-sport decisions for patients undergoing both procedures.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 to 50 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
- Study population
- Patients will be recruited from those surgically treated at the Second Clinic of the Rizzoli Orthopaedic Institute, undergoing anterior cruciate ligament reconstruction using the "over-the-top" single-bundle technique with gracilis and semitendinosus tendons, combined with lateral extra-articular tenodesis (LET). Only patients with at least 6 months of follow-up after the surgery date will be enrolled. Subsequently, patients will be re-evaluated during a 12-month follow-up visit, as per standard clinical practice for this procedure.
Key inclusion criteria (4 listed)
- Patients undergoing isolated ACL reconstruction using gracilis and semitendinosus tendons with the over-the-top technique and LET.
- Both male and female patients.
- Patients who have given consent to participate in the study.
- Age between 18 and 50 years at the time of surgery.
Key exclusion criteria (5 listed)
- Previous surgery on the same limb (meniscectomy, prior ACL reconstruction, displaced fractures).
- Surgical technique different from Over-the-Top with LET using autologous gracilis and semitendinosus tendons.
- Other concomitant ligament injuries requiring surgical treatment.
- Patients undergoing additional procedures at the same time as ACL reconstruction and LET (e.g., concomitant osteotomy, meniscus transplant, cartilage procedure…).
- Patients who did not provide informed consent.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
KYRA accelerometer
Time frame: 12 months
KYRA is a non-invasive outpatient device that allows the assessment of dynamic laxity during the pivot shift phenomenon. The device enables highly precise quantification of the degree of laxity. The unit of measurement is millimeters per second squared.
10 secondary outcomes
KT-1000 Arthrometer
Time frame: 12 months
Physical Examination
Time frame: 12 months
Anterior Drawer Test
Time frame: 12 months
Lachman Test
Time frame: 12 months
Pivot Shift Test
Time frame: 12 months
Knee Injury and Osteoarthritis Outcome Score (KOOS)
Time frame: 12 months
Lysholm Knee Score
Time frame: 12 months
VAS (Visual Analog Scale)
Time frame: 12 months
Tegner Score
Time frame: 12 months
Complications or Subsequent Interventions
Time frame: 12 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Apr 2026.
Related trials for ACL Reconstruction
Not yet recruiting
Stair Biomechanics and Vibration Study After ACLR
Anterior Cruciate Ligament Reconstruction (ACLR), Anterior Cruciate Ligament Injury
Not yet recruiting
Nerve Block of the Vastus Medialis and Anterior Obturator Branch in Anterior Cruciate Ligament Reconstruction With DIDT Graft
Anterior Cruciate Ligament (ACL) Reconstruction Surgery
Not yet recruiting
Supporting Athletes' Return to Sports After ACL Reconstruction: A Study of a Psychological Readiness Program
Anterior Cruciate Ligament Reconstruction, Anterior Cruciate Ligament Injuries
Recruiting
Interventions to Enhance Quadriceps Output After ACLR
ACL
Recruiting
Graded Exposure and Mindfulness Meditation for Patients Post-ACL Reconstruction
Anterior Cruciate Ligament Injuries
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of ACL Reconstruction and Tenodesis, run by Stefano Zaffagnini at 1 site in Italy.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 22 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact stefano zaffagnini (0516366075, stefano.zaffagnini@unibo.it), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
KYRA accelerometer (time frame: 12 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 Apr 2026.