NCT07830953

Brief Summary

This prospective, randomized controlled trial will compare three tibial interference screw types used for graft fixation during primary anterior cruciate ligament (ACL) reconstruction: a polyetheretherketone (PEEK) screw, a biocomposite screw, and an allograft bone screw. Although interference screws are widely used for tibial fixation, the optimal screw material remains uncertain, particularly regarding its effect on tibial tunnel widening and graft incorporation. Adult patients undergoing primary ACL reconstruction with a quadriceps tendon autograft using a standardized surgical technique will be randomly assigned to one of the three tibial fixation methods. The primary outcome is tibial tunnel widening measured by computed tomography (CT) 12 months after surgery. Secondary outcomes include graft integration assessed by magnetic resonance imaging (MRI) and patient-reported clinical outcomes, including the Lysholm, Tegner, KOOS, and ACL-Return to Sport after Injury (ACL-RSI) scores, collected during routine follow-up. The study aims to determine whether allograft bone screws reduce tunnel widening and improve graft integration compared with PEEK and biocomposite screws while maintaining comparable clinical outcomes.

Trial Health

63
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
33

participants targeted

Target at P25-P50 for not_applicable

Timeline
26mo left

Started Nov 2026

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

July 18, 2026

Completed
2 months until next milestone

First Posted

Study publicly available on registry

September 21, 2026

Completed
1 month until next milestone

Study Start

First participant enrolled

November 1, 2026

Expected
2.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2028

Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2028

Last Updated

September 21, 2026

Status Verified

September 1, 2026

Enrollment Period

2.2 years

First QC Date

July 18, 2026

Last Update Submit

September 15, 2026

Conditions

ACL - Anterior Cruciate Ligament Rupture

Keywords

ACL RuptureACL Reconstruction

Outcome Measures

Primary Outcomes (1)

  • Tibial Tunnel Widening

    CT Measurement of the tibial Tunnel Widening in mm. The difference will be calculated between drilled diameter and measured diameter.

    1 Year Postop

Secondary Outcomes (4)

  • MRI Graft Integration

    6 Months and 1 Year

  • Lysholm

    1 Year postop

  • Tegner

    Preop, 1 year postop

  • ACL-RSI

    12 month postop

Study Arms (3)

Biocomposite Interference Screw

ACTIVE COMPARATOR

Biocomposite Interference Screw Fixation of the Tibial End of the Graft

Procedure: ACL Reconstruction with a Biocomposite Screw

PEEK Interference Screw

ACTIVE COMPARATOR

Polyether Ether Ketone Interference Screw Fixation of the Tibial End of the Graft

Procedure: ACL Reconstruction using a PEEK Screw

Shark Screw

EXPERIMENTAL

Allograft Bone Interference Screw Fixation of the Tibial End of the Graft

Procedure: ACL Reconstruction using an Allograft Screw

Interventions

ACL Reconstruction with a Biocomposite ScrewPROCEDURE

ACL Reconstruction using a standardized technique. Tibial Fixation using a Biocomposite Screw.

Biocomposite Interference Screw
ACL Reconstruction using a PEEK ScrewPROCEDURE

ACL Reconstruction using a standardized technique. Tibial Fixation using a PEEK Screw.

PEEK Interference Screw
ACL Reconstruction using an Allograft ScrewPROCEDURE

ACL Reconstruction using a standardized technique. Tibial Fixation using a SharkScrew Allograft Interference Screw.

Shark Screw

Eligibility Criteria

Age18 Years - 70 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Male and non-pregnant female patients aged 18-70 years
  • MRI-confirmed rupture of the anterior cruciate ligament (ACL)
  • Clinically positive anterior drawer test and Lachman test
  • Subjective instability
  • Clinically and MRI-confirmed intact posterior cruciate ligament (PCL), medial collateral ligament (MCL), and posterolateral corner
  • Written informed consent obtained
  • Patient is able and willing to participate in the study

You may not qualify if:

  • Previous surgery on the affected knee joint (ACL reconstruction, fracture fixation, osteotomy, or partial joint replacement)
  • Body mass index (BMI) \> 40
  • Coronal instability due to injury of the medial collateral ligament or posterolateral corner
  • Meniscal injury requiring postoperative restriction of weight-bearing (e.g., root tears, radial tears)
  • The patient is unable to speak German
  • The patient is pregnant

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

AUVA UKH Steiermark, Standort Graz

Graz, Styria, 8044, Austria

Location

MeSH Terms

Conditions

Anterior Cruciate Ligament Injuries

Condition Hierarchy (Ancestors)

Knee InjuriesLeg InjuriesWounds and Injuries

Central Study Contacts

Antonio Klasan, MD, PhD, EMBA, FRCS

CONTACT

+43 676 5085920klasan.antonio@me.com

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 18, 2026

First Posted

September 21, 2026

Study Start (Estimated)

November 1, 2026

Primary Completion (Estimated)

December 31, 2028

Study Completion (Estimated)

December 31, 2028

Last Updated

September 21, 2026

Record last verified: 2026-09

Data Sharing

IPD Sharing
Will not share

Locations

AU(1)