ACLACL_50_YONCT07041242
Outcomes and Complication Rates of Anterior Cruciate Ligament Reconstruction Using the "Over-the-top" Technique Combined With Lateral Extra-articular Tenodesis in Patients Over 50 Years Old, Compared With a Control Group of Patients Under 30
An observational study of ACL and LET, 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, and its injury is among the most common soft tissue injuries of the knee. Surgical reconstruction of the ACL can be performed using various techniques and different types of tissue grafts, including both autografts and allografts. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- ACL, LET, Hamstring Muscles
- What is being tested?
- ligament reconstruction using the single-bundle "over-the-top" technique
- Type of treatment
- Surgery or procedure
- How many people
- 164 participants
- Where
- 1 siteItaly
- Study dates
- 13 Jul 2025to Jun 2027
- 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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients will be recruited from both male and female subjects over 50 years of age at the time of surgery (study group), and adult patients, also both male and female, aged between 18 and 30 years at the time of surgery (control group), who underwent surgical treatment at the II Clinic of the Rizzoli Orthopaedic Institute by means of single-bundle "over-the-top" anterior cruciate ligament reconstruction using the gracilis and semitendinosus tendons, combined with lateral extra-articular tenodesis. Only patients at least 2 years post-surgery will be enrolled. Patients will be recruited evenly and progressively to ensure proper matching of the two groups with respect to patient characteristics. For each patient over 50 included in the study, a patient under 30 with similar characteristics (total follow-up duration, sex, concomitant meniscal injuries at the time of surgery) will be included to guarantee a balanced comparison between the two patient cohorts.
Who may be able to join
- Patients operated on between 2007 and 2023 who were over 50 years old at the time of surgery (study group) and patients under 30 years old at the time of surgery (control group).
- Patients who underwent ACL reconstruction using the gracilis and semitendinosus tendons with the over-the-top + LET technique.
- Patients of both male and female sex.
- Patients who have provided consent to participate in the study.
Who cannot join
- Previous surgery on the same limb (meniscectomy, prior ACL reconstruction, surgically treated fractures, osteotomies, meniscal transplants).
- Concomitant surgery on the same limb (osteotomies, meniscal transplants).
- Surgical technique different from the over-the-top with LET using autologous gracilis and semitendinosus tendons.
- Other concomitant ligament injuries requiring surgical treatment.
- Patients younger than 18 years at the time of surgery (minors) or patients aged between 30 and 50 years at the time of surgery.
- Patients who have not provided informed consent.
- Patients with a follow-up period shorter than 2 years.
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, Bologna, 40136
Stefano Zaffagnini, 0516366075, stefano.zaffagnini@ior.it
About this study
The anterior cruciate ligament (ACL) is one of the main stabilizers of the knee, and its injury is among the most common soft tissue injuries of the knee. Surgical reconstruction of the ACL can be performed using various techniques and different types of tissue grafts, including both autografts and allografts.
Although ACL reconstruction is a widely performed surgical procedure in young and physically active individuals-typically patients under 30 years of age-to promote return to sports and prevent early onset of osteoarthritic degeneration, the surgical approach has historically been less common in patients over the age of 50. This is largely due to the lower functional demands typically observed in older patients.
Read more
However, with increasing life expectancy and a corresponding rise in functional demands among older individuals, the surgical approach to ACL reconstruction has been progressively reconsidered in the over-50 population. Several recent studies have aimed to evaluate the outcomes of ACL reconstruction in older adults, showing promising results in terms of both recurrence rates and complication rates.
At the II Clinic of the Rizzoli Orthopaedic Institute, under the direction of Professor Zaffagnini, the preferred technique for ACL reconstruction is the "single-bundle over-the-top technique using gracilis and semitendinosus tendons, combined with a lateral extra-articular tenodesis (LET)." LET is an additional surgical step performed alongside ACL reconstruction, which has shown excellent results, especially in young patients at high risk of reinjury. Specifically, clinical data have shown that adding LET to ACL reconstruction can reduce the failure rate by approximately 30%, significantly improve knee stability, and enable a faster return to sports-all without increasing the rate of complications compared to the standard isolated ACL reconstruction technique.
Given these encouraging results in terms of safety and reduced failure rates, the combined ACL + LET procedure has historically been used at the Rizzoli Orthopaedic Institute for all patients, including those over 50 years of age.
The consistent use of this technique allows for the creation of a homogeneous patient cohort, all treated with the same surgical approach. This also enables the formation of two comparable patient groups-one over 50 and one under 30-both treated with the same technique, allowing for a meaningful comparison of primary and secondary endpoints.
While several studies have aimed to compare ACL reconstruction outcomes in older populations with those in younger cohorts, to date, there are no studies in the literature that specifically assess the outcomes and complication rates of ACL reconstruction using the over-the-top technique combined with LET in patients over 50, and compare them with those of younger patients undergoing the same surgical procedure.
Given the growing demand for ACL reconstruction in older patients, we believe it is important to evaluate outcomes in patients over 50 and compare them with a younger cohort, to determine whether the over-the-top + LET technique may be a valid therapeutic option not only for young patients but also for older adults.
Of particular interest is the assessment of the reduced risk of failure and complication rate of the ACL + LET technique performed in over-50 patients, to determine whether the excellent clinical outcomes observed in younger individuals are also confirmed in an older population.
- Conditions
- ACL, LET, Hamstring Muscles
- Being tested
- ligament reconstruction using the single-bundle "over-the-top" technique
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ligament reconstruction using the single-bundle "over-the-top" techniqueProcedure or surgery
Patients who have undergone anterior cruciate ligament reconstruction using the single-bundle "over-the-top" technique with gracilis and semitendinosus tendons, combined with a lateral extra-articular tenodesis, will be enrolled
| Study group | Role | What they receive |
|---|---|---|
| over 50 | Not described Receives: Procedure: ligament reconstruction using the single-bundle "over-the-top" technique | |
| under 30 | Not described Receives: Procedure: ligament reconstruction using the single-bundle "over-the-top" technique |
What is being measured
The primary outcome is the main question the study is designed to answer.
Complications
Any complications and subsequent procedures 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 front page of each questionnaire in order to safeguard the privacy of the study participants.
Measured: 2 years
Secondary outcomes (4)
Lysholm Knee Score
It is a validated measurement scale that assesses knee functionality through 8 items, which help determine the condition of the knee in response to the functional demands of daily activities. This evaluation form is used to assess surgical outcomes in patients who have undergone surgery for ligament or meniscal injuries of the knee.
The final score is obtained by summing the individual item scores and ranges from 0 to 100. The scores are classified into subgroups as follows:
- Excellent (95-100)
- Good (84-94)
- Fair (65-83)
- Poor (<64)
Measured: 2 years
Knee Injury and Osteoarthritis Outcome Score (KOOS)
The Knee Injury and Osteoarthritis Outcome Score (KOOS) is used to assess both short-term and long-term outcomes in patients following a knee injury. The self-administered KOOS evaluates five domains: pain, symptoms, activities of daily living, sport and recreational function, and knee-related quality of life.
KOOS meets core standards for outcome measures and can be used to monitor the progression of knee injury and the effectiveness of treatment. The KOOS questionnaire includes five dimensions relevant to patients: pain, symptoms, daily living activities, sports and recreational activities, and quality of life.
Each dimension is assessed separately using a five-point Likert scale, ranging from 0 (no problems) to 4 (extreme problems).
Measured: 2 years
Visual Analog Scale (VAS)
The Visual Analog Scale (VAS) is a one-dimensional, quantitative 10-point numerical scale used to assess pain. Patients are asked to select the number that best describes the intensity of their pain at that specific moment, with 0 indicating no pain and 10 representing the worst possible pain.
This scale will also be used to assess both preoperative and postoperative pain in the lateral compartment of the knee. The data will help evaluate the onset of pain following surgery, specifically in the area where metal staples are placed for graft fixation during the lateral extra-articular tenodesis procedure.
Pain reported in the lateral femorotibial compartment with a VAS score greater than 2 will be considered indicative of the presence of lateral compartment pain, while a score of 2 or less will be considered as the absence of pain in that area.
Measured: 2 years
Tegner Score
This scale is used to estimate an individual's level of physical activity, with scores ranging from 0 to 10. A score of 0 represents "disability," while a score of 10 indicates participation in competitive sports, such as national or international level football. The Tegner Score is one of the most commonly used tools to define the activity level of patients with knee disorders.
In this study, the Tegner Score will be completed directly by the investigator through an interview with the patient.
Measured: 2 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Jun 2025
- Study start13 Jul 2025
- Primary completionJun 2027 (estimated)
- Study completionJun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ACLStudies 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
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 164 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
- NCT07041242
- Sponsor's protocol ID
- ACL_50_YO
- Acronym
- ACL_50_YO
- Status last verified
- Jun 2026
- First submitted
- 19 Jun 2025
- Last updated
- 4 Sep 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 4 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Outcomes and Complication Rates of Anterior Cruciate Ligament Reconstruction Using the "Over-the-top" Technique Combined With Lateral Extra-articular Tenodesis in Patients Over 50 Years Old, Compared With a Control Group of Patients Under 30
- ClinicalTrials.gov ID
- NCT07041242
- Acronym / sponsor ID
- ACL_50_YO / ACL_50_YO
- Conditions
- ACL, LET, Hamstring Muscles
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 164 participants (estimated)
- Lead sponsor
- Stefano ZaffagniniUniversity, hospital or other
- Study start
- 13 Jul 2025 (actual)
- Primary completion
- Jun 2027 (estimated)
- Study completion
- Jun 2027 (estimated)
- First posted
- 27 Jun 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, and its injury is among the most common soft tissue injuries of the knee. Surgical reconstruction of the ACL can be performed using various techniques and different types of tissue grafts, including both autografts and allografts.
Although ACL reconstruction is a widely performed surgical procedure in young and physically active individuals-typically patients under 30 years of age-to promote return to sports and prevent early onset of osteoarthritic degeneration, the surgical approach has historically been less common in patients over the age of 50. This is largely due to the lower functional demands typically observed in older patients.
However, with increasing life expectancy and a corresponding rise in functional demands among older individuals, the surgical approach to ACL reconstruction has been progressively reconsidered in the over-50 population. Several recent studies have aimed to evaluate the outcomes of ACL reconstruction in older adults, showing promising results in terms of both recurrence rates and complication rates.
At the II Clinic of the Rizzoli Orthopaedic Institute, under the direction of Professor Zaffagnini, the preferred technique for ACL reconstruction is the "single-bundle over-the-top technique using gracilis and semitendinosus tendons, combined with a lateral extra-articular tenodesis (LET)." LET is an additional surgical step performed alongside ACL reconstruction, which has shown excellent results, especially in young patients at high risk of reinjury. Specifically, clinical data have shown that adding LET to ACL reconstruction can reduce the failure rate by approximately 30%, significantly improve knee stability, and enable a faster return to sports-all without increasing the rate of complications compared to the standard isolated ACL reconstruction technique.
Given these encouraging results in terms of safety and reduced failure rates, the combined ACL + LET procedure has historically been used at the Rizzoli Orthopaedic Institute for all patients, including those over 50 years of age.
The consistent use of this technique allows for the creation of a homogeneous patient cohort, all treated with the same surgical approach. This also enables the formation of two comparable patient groups-one over 50 and one under 30-both treated with the same technique, allowing for a meaningful comparison of primary and secondary endpoints.
While several studies have aimed to compare ACL reconstruction outcomes in older populations with those in younger cohorts, to date, there are no studies in the literature that specifically assess the outcomes and complication rates of ACL reconstruction using the over-the-top technique combined with LET in patients over 50, and compare them with those of younger patients undergoing the same surgical procedure.
Given the growing demand for ACL reconstruction in older patients, we believe it is important to evaluate outcomes in patients over 50 and compare them with a younger cohort, to determine whether the over-the-top + LET technique may be a valid therapeutic option not only for young patients but also for older adults.
Of particular interest is the assessment of the reduced risk of failure and complication rate of the ACL + LET technique performed in over-50 patients, to determine whether the excellent clinical outcomes observed in younger individuals are also confirmed in an older population.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| over 50 | – | Procedure: ligament reconstruction using the single-bundle "over-the-top" technique |
| under 30 | – | Procedure: ligament reconstruction using the single-bundle "over-the-top" technique |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients will be recruited from both male and female subjects over 50 years of age at the time of surgery (study group), and adult patients, also both male and female, aged between 18 and 30 years at the time of surgery (control group), who underwent surgical treatment at the II Clinic of the Rizzoli Orthopaedic Institute by means of single-bundle "over-the-top" anterior cruciate ligament reconstruction using the gracilis and semitendinosus tendons, combined with lateral extra-articular tenodesis. Only patients at least 2 years post-surgery will be enrolled. Patients will be recruited evenly and progressively to ensure proper matching of the two groups with respect to patient characteristics. For each patient over 50 included in the study, a patient under 30 with similar characteristics (total follow-up duration, sex, concomitant meniscal injuries at the time of surgery) will be included to guarantee a balanced comparison between the two patient cohorts.
Key inclusion criteria (4 listed)
- Patients operated on between 2007 and 2023 who were over 50 years old at the time of surgery (study group) and patients under 30 years old at the time of surgery (control group).
- Patients who underwent ACL reconstruction using the gracilis and semitendinosus tendons with the over-the-top + LET technique.
- Patients of both male and female sex.
- Patients who have provided consent to participate in the study.
Key exclusion criteria (7 listed)
- Previous surgery on the same limb (meniscectomy, prior ACL reconstruction, surgically treated fractures, osteotomies, meniscal transplants).
- Concomitant surgery on the same limb (osteotomies, meniscal transplants).
- Surgical technique different from the over-the-top with LET using autologous gracilis and semitendinosus tendons.
- Other concomitant ligament injuries requiring surgical treatment.
- Patients younger than 18 years at the time of surgery (minors) or patients aged between 30 and 50 years at the time of surgery.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ligament reconstruction using the single-bundle "over-the-top" techniquePatients who have undergone anterior cruciate ligament reconstruction using the single-bundle "over-the-top" technique with gracilis and semitendinosus tendons, combined with a lateral extra-articular tenodesis, will be enrolled | Procedure or surgery | over 50, under 30 |
Primary outcome
Complications
Time frame: 2 years
Any complications and subsequent procedures 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 front page of each questionnaire in order to safeguard the privacy of the study participants.
4 secondary outcomes
Lysholm Knee Score
Time frame: 2 years
Knee Injury and Osteoarthritis Outcome Score (KOOS)
Time frame: 2 years
Visual Analog Scale (VAS)
Time frame: 2 years
Tegner Score
Time frame: 2 years
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 4 Sep 2026.
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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 and LET, 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 7 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 4 Sep 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?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Complications (time frame: 2 years). 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 4 Sep 2026.