Mid-term Postoperative Clinical Evaluation of Patients Undergoing Anterior Cruciate Ligament (ACL) Reconstruction Using the Over-The-Top Technique, Fixed With Metal Staples or Soft Anchors. (Metal-free OTT)

Mid-term Postoperative Clinical Evaluation of Patients Undergoing Anterior Cruciate Ligament (ACL) Reconstruction Using the Over-The-Top Technique, Fixed With Metal Staples or Soft Anchors

Anterior cruciate ligament (ACL) reconstruction is a widely performed procedure aimed at restoring knee stability and enabling return to sports activities. The Over-The-Top (OTT) technique is a well-established option, particularly in complex and revision cases, due to its ability to provide both anteroposterior and rotational stability. Long-term studies have reported favorable clinical outcomes, with low failure rates.

Graft fixation is an important technical aspect that may influence postoperative outcomes. Traditionally, the OTT technique has been performed using metal staples, which provide reliable primary fixation but may cause local complications and sometimes require subsequent removal due to pain or discomfort.

More recently, suture-based fixation devices, such as Knee FiberTak anchors (Arthrex), have been introduced as a metal-free alternative. These devices allow graft fixation through high-strength sutures, providing stable graft-to-bone contact while minimizing bony invasiveness and hardware prominence.

The present study aims to evaluate the clinical, functional, and instrumental outcomes of ACL reconstruction using the OTT technique with graft fixation by suture anchors compared with traditional metal staples. Particular attention will be paid to postoperative knee stability, assessed using validated instruments (KT-1000 and KiRA), as well as failure rates, reoperations, and complications.

Study Overview

• Status: Not yet recruiting
• Conditions: ACL Reconstruction; Fixation
• Intervention / Treatment: Procedure: ACL reconstruction using the Over-The-Top technique

• Study Type: Interventional
• Enrollment (Estimated): 46
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Stefano Zaffagnini; Phone Number: 0516366075; Email: stefano.zaffagnini@ior.it

Study Locations

• Italy
  • Bologna, Italy, 40136
    • IRCCS Rizzoli Orthopedic Institute
    • Contact: Stefano Zaffagnini; Phone Number: 0516366075; Email: stefano.zaffagnini@ior.it

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients of either sex, aged between 18 and 50 years at the time of surgery;
2. Patients with an isolated anterior cruciate ligament (ACL) injury, with or without associated meniscal lesions, scheduled for ACL reconstruction and meniscal treatment; .3 Patients whose contralateral knee has never undergone meniscectomy, ligament reconstruction, unicompartmental knee arthroplasty, or total knee arthroplasty;

4. Patients who have signed the informed consent form.

Exclusion Criteria:

1. Patients with associated injury of the medial collateral ligament (MCL), lateral collateral ligament (LCL), posterolateral corner (PLC), or posterior cruciate ligament (PCL);
2. Patients with complete meniscal root tears, complete radial tears, or lateral meniscus oblique tears (LMORT);
3. Patients who underwent total or subtotal medial or lateral meniscectomy;
4. Patients with grade III-IV chondral lesions according to the Outerbridge classification identified at the time of surgery;
5. Patients who are unable to provide informed consent or who are unwilling to provide informed consent;
6. Patients with insufficient and/or compromised bone quality or quantity due to disease, infection, or previous implantation, such that adequate support and/or fixation of the devices cannot be ensured;
7. Patients with limited blood supply or a history of infections that could delay healing;
8. Patients with sensitivity to foreign materials.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Metal staples	Procedure: ACL reconstruction using the Over-The-Top technique; The procedure involves ACL reconstruction using the Over-The-Top technique, with the graft positioned over the lateral femoral condyle to provide anteroposterior and rotational stability. The graft is secured using either metal staples or suture anchors, according to the assigned fixation technique.
Experimental: Soft anchors	Procedure: ACL reconstruction using the Over-The-Top technique; The procedure involves ACL reconstruction using the Over-The-Top technique, with the graft positioned over the lateral femoral condyle to provide anteroposterior and rotational stability. The graft is secured using either metal staples or suture anchors, according to the assigned fixation technique.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
KT-1000	The KT-1000 is a clinical-instrumental test widely used for the standardized assessment of patients undergoing anterior cruciate ligament (ACL) reconstruction. It provides an objective measurement of anterior-posterior knee laxity and is extensively used in both clinical practice and scientific research. The assessment is performed with the patient in a supine position, with the knee flexed to approximately 30° and supported on a dedicated device. The examiner applies a standardized anterior load to the tibia while stabilizing the femur, and the resulting anterior-posterior displacement is recorded by sensors positioned in contact with the patella and tibial tuberosity. The measurement does not have a predefined minimum or maximum value. Lower values indicate less anterior laxity and therefore better knee stability, whereas higher values indicate greater anterior laxity and worse knee stability.	At least 24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
KiRA	For quantitative assessment of the Pivot Shift test, the KiRA sensor is secured to the skin over the anterolateral proximal tibia, specifically at the level of Gerdy's tubercle, using a hypoallergenic strap and an appropriate support to optimize stability. The device, which incorporates a triaxial accelerometer and gyroscope, communicates wirelessly with a dedicated application installed on a tablet, providing real-time quantification of tibial displacement during the clinical maneuver. KiRA measurements are expressed in millimeters (mm) and represent the magnitude of anterior tibial displacement. There is no predefined minimum or maximum value for this continuous measurement; lower values indicate less tibial displacement and therefore better rotational stability, whereas higher values indicate greater displacement and worse rotational stability.	At least 24 months
IKDC standard evaluation form	This is a clinical assessment form completed by the physician following a thorough physical examination of the knee. It includes several clinical tests to assess joint deformities, objective instability, and meniscal injuries. The resulting score determines an objective functional grade, classified from A to D: **A**, normal; **B**, nearly normal; **C**, moderately abnormal; and **D**, severely abnormal.	At least 24 months
Lysholm Knee Score	This is a validated outcome measure that assesses knee function through 8 items designed to evaluate the knee's ability to meet the functional demands of daily activities. It is commonly used to assess surgical outcomes in patients undergoing treatment for knee ligament or meniscal injuries. The final score is calculated by summing the scores obtained across the individual items, ranging from 0 to 100. Scores are classified as **Excellent (95-100), Good (84-94), Fair (65-83), and Poor (<64)**.	At least 24 months
VAS	This is a 10-point unidimensional numerical scale used to assess pain intensity. The patient selects the number that best represents their pain intensity at that specific moment, ranging from 0 (no pain) to 10 (worst possible pain)	At least 24 months
SF-12 (Short Form-12 Health Survey)	This is a 12-item multiple-choice questionnaire that provides two main summary measures: the **Physical Component Summary (PCS)** and the **Mental Component Summary (MCS)**. Together, these scores provide a concise and reliable assessment of the patient's overall health status. Scores are typically reported on a 0-100 scale, with higher scores indicating better health-related quality of life.	At least 24 months
KOOS (Knee Injury and Osteoarthritis Outcome Score)	This is a validated, knee-specific outcome measure used to assess symptoms and function in patients with ligament injuries or degenerative knee conditions. It consists of five subscales: **Pain, Other Symptoms, Activities of Daily Living (ADL), Sport and Recreation Function, and Knee-Related Quality of Life (QOL)**, providing a comprehensive assessment of the impact of knee pathology and treatment on joint function and quality of life. Each subscale is scored from 0 to 100, with higher scores indicating better knee function and fewer symptoms, while lower scores indicate worse outcomes.	At least 24 months
Tegner Score	The Tegner Activity Scale is a validated measure used to assess the patient's level of physical activity on a scale from **0 to 10**, where 0 represents disability and 10 represents participation in competitive sports at a national or international level, such as football. It is widely used to assess activity levels in patients with knee disorders. Patients will also be asked how many years they have been physically active in sports and whether any reduction or cessation of sporting activity is related to their knee condition.	At least 24 months
Patient Satisfaction	To assess the patient's level of satisfaction, patients will be asked the following question: "Are you satisfied with the surgical procedure?" The response will be dichotomous (yes/no)	At least 24 months

Collaborators and Investigators

• Sponsor: Stefano Zaffagnini

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): August 1, 2030
• Study Completion (Estimated): August 1, 2030

Study Registration Dates

• First Submitted: September 1, 2026
• First Submitted That Met QC Criteria: September 14, 2026
• First Posted (Actual): September 15, 2026

Study Record Updates

• Last Update Posted (Actual): September 15, 2026
• Last Update Submitted That Met QC Criteria: September 14, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: Metal-free OTT

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No