Tibial Tunnel Widening in Anterior Cruciate Ligament (ACL) Reconstruction-Comparing Two Bioscrews

Brief Title

Tibial Tunnel Widening in Anterior Cruciate Ligament (ACL) Reconstruction-Comparing Two Bioscrews

Official Title

Tibial Tunnel Widening in ACL Reconstruction-Comparing Two Bioscrews: A Prospective Randomized Clinical Trial

Brief Summary

      Widening of the single tibial tunnel following ACL surgery with quadrupled hamstrings
      autograft may contribute to failure of the graft and/or present technical challenges
      secondary to bone loss in a revision setting (Getelman, 1999). As such, efforts should be
      made to minimize the incidence and magnitude of tibial tunnel widening without sacrificing
      the biomechanical properties of the graft construct. The purpose of this investigation is to
      examine the tibial tunnel widening relationship between bioabsorbable interference screws
      composed of poly-L-lactic acid (PLLA) alone and composite bioabsorbable interference screws
      composed of poly-L-lactic acid embedded with beta tricalcium phosphate (PLLA+TCP) utilized as
      tibial fixation devices.

      Specifically the study has the following objectives: 1) To quantify the extent of tibial
      tunnel enlargement at 3-, 6- and 12-months post ACL reconstruction with autogenous quadrupled
      hamstring graft; 2) To determine if the incorporation of beta tricalcium phosphate to the
      bioabsorbable interference screw alters the observed magnitude of tunnel widening; 3) To
      hypothesize mechanisms for any observed differences between tibial fixation devices; and 4)
      To correlate tibial tunnel widening with clinical outcome status. It is hypothesized that the
      PLLA+TCP bioabsorbable interference screw will not be associated with a reduction in tibial
      tunnel widening around the implant but rather between the implant and articular surface,
      compared to the PLLA alone screw. It is also hypothesized that there will be no effect of
      observed tunnel widening on clinical outcomes or graft failure rates.

Study Type


Primary Outcome


Secondary Outcome

 ACL Quality of Life Scores




Linvatec PLLA+TCP

Study Arms / Comparison Groups

 PLLA bioscrew
Description:  poly-L-lactic acid bioscrew


* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Information

Recruitment Status


Estimated Enrollment


Start Date

November 2012

Completion Date

December 2018

Primary Completion Date

April 2018

Eligibility Criteria

        Inclusion Criteria:

          -  Must have a unilateral ACL rupture

          -  Patients must be between 18 and 45 years old

        Exclusion Criteria:

          -  Concomitant medial collateral, lateral collateral, or posterior collateral ligament

          -  Severe chondromalacia or severe meniscal tear

          -  Previous history of ipsilateral knee joint pathology, surgery, or trauma to that knee

          -  Unwillingness to be followed for 12 months post-operatively

          -  History of arthritis (osteoarthritis or rheumatoid)

          -  Pregnancy

          -  Psychiatric illness that precludes informed consent

          -  Unable to speak or read English/French

          -  Major medical illness (life expectancy less than 1 year or unacceptably high operative




18 Years - 45 Years

Accepts Healthy Volunteers



Peter B MacDonald, MD FRCS(C), , 

Location Countries


Location Countries


Administrative Informations



Organization ID


Responsible Party

Principal Investigator

Study Sponsor

Panam Clinic

Study Sponsor

Peter B MacDonald, MD FRCS(C), Principal Investigator, Pan Am Clinic

Verification Date

March 2019