Biological Potentials in Arthroscopic All-inside Semitendinosus Anterior Cruciate Ligament Reconstruction

N/ANot Yet RecruitingNCT07506304

University Hospital Dubrava70 enrolled

Overview

A randomized, double-blind, prospective single-center clinical trial evaluating the effect of biological augmentation in anterior cruciate ligament (ACL) reconstruction. The study compares standard all-inside semitendinosus ACL reconstruction versus biologically enhanced reconstruction incorporating muscle tissue preservation and autologous bone and fibrin augmentation. The primary aim is to assess whether biological augmentation improves graft healing, integration, and clinical outcomes.

Anterior cruciate ligament (ACL) reconstruction outcomes depend on multiple factors including surgical technique, graft selection, fixation methods, and rehabilitation. Hamstring tendon autografts are commonly used due to favorable biomechanical properties and low donor-site morbidity. Traditionally, graft preparation involves complete removal of muscle tissue; however, emerging techniques such as the "candy stripe" method preserve residual muscle, which may provide a source of stem cells and enhance biological healing. In addition, biological augmentation strategies-including the use of autologous bone graft and platelet-rich fibrin (PRF)-have been proposed to improve tendon-to-bone integration and accelerate ligamentization. These approaches aim to enhance graft incorporation, structural integrity, and overall functional recovery. This study is a double-blind, randomized, prospective, single-center clinical trial including 70 patients with ACL rupture. Participants are randomly assigned into two groups (n=35 per group): A control group undergoing standard all-inside ACL reconstruction. An intervention group undergoing biologically augmented ACL reconstruction. All procedures are performed using an all-inside technique with semitendinosus tendon autografts. The biologically augmented group differs by: Preservation of a thin layer of muscle tissue on the graft (candy stripe technique) Use of autologous cancellous bone collected during tunnel drilling Application of autologous fibrin glue (platelet-rich fibrin) combined with bone graft to enhance healing at graft-tunnel interfaces The primary objective is to evaluate whether biological augmentation improves graft healing and clinical outcomes compared to standard reconstruction.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

Interventions

ACL reconstructionPROCEDURE

Participants will undergo arthroscopic all-inside anterior cruciate ligament reconstruction using an autologous semitendinosus graft. In the experimental intervention, a biologically augmented graft is used, including preservation of muscle tissue on the tendon (candy stripe technique) and application of autologous cancellous bone combined with platelet-rich fibrin at the graft-bone interface. In the control intervention, a standard tendon-only graft is used without biological augmentation. In both groups, graft configuration, tunnel creation, fixation technique, and surgical protocol are identical, and all procedures are performed by the same surgeon.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 50 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Clinically and radiologically confirmed anterior cruciate ligament (ACL) rupture. * Age between 18 and 50 years. * Intact posterior cruciate ligament and collateral ligaments. * Signed informed consent to participate in the study. * Patients meeting at least one indication for concomitant lateral tenodesis, including: age under 25 years, positive pivot-shift test, presence of Segond fracture, participation in sports with frequent changes of direction and rotational knee loads, or joint hypermobility (Beighton score ≥ 7). Exclusion Criteria: * Previous ACL reconstruction of the same knee. * Inability to use a graft prepared by quadruple folding of the semitendinosus tendon. * Graft diameter \< 7.5 mm. * MRI-confirmed unsuccessful meniscal healing after repair. * Acute joint infection or history of joint infection.

Outcomes

Primary Outcomes

SNQ

To analyze and compare T2 signal-to-noise ratio values on magnetic resonance imaging at 6 weeks, 6 and 12 months postoperatively within and between the two study groups. The SNQ is calculated as the ratio of the graft T2 signal intensity to the signal intensity of a reference tissue on MRI. Higher SNQ values indicate higher graft signal, which corresponds to lower graft maturity/quality. Scale: Continuous numerical value (exact values depend on MRI signal calibration).

Time frame: 6 weeks, 6 and 12 months postoperatively

Secondary Outcomes

Bone Tunnel Diameter

The diameter of the femoral and tibial bone tunnel measured on MRI at 6 and 12 months postoperatively compared to the intraoperatively drilled diameter. Units: Millimeters (mm) Directionality: Higher values indicate tunnel widening

Time frame: 6 and 12 months postoperatively

Knee Stability - Anterior Tibial Translation

The anterior-posterior stability of the operated knee measured with the Lachmeter device at 12 months postoperatively. Units: Millimeters (mm) of anterior tibial translation Directionality: Higher values indicate greater laxity (worse stability)

Time frame: 12 months postoperatively

KOOS - Pain Subscale

Knee Injury and Osteoarthritis Outcome Score (KOOS) - Pain subscale, assessing knee pain. Scale: 0-100 (0 = extreme pain, 100 = no pain; higher scores = better outcome)