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

Study Overview
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Brief Summary
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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.

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

Conditions
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ACL

Intervention / Treatment
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* Device: Linvatec PLLA+TCP
* Device: Linvatec PLLA


Participation Criteria
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Eligibility Criteria
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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 tears 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 risk)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: PLLA bioscrew<br>poly-L-lactic acid bioscrew | Device: Linvatec PLLA<br>* Linvatec PLLA tibial interference screw fixation will be used in ACL reconstruction.<br>|
| Active Comparator: PLLA+TCP bioscrew<br>poly-l-lactic acid with beta tricalcium phosphate bioscrew | Device: Linvatec PLLA+TCP<br>* Linvatec PLLA+TCP tibial interference screw fixation will be used in ACL reconstruction.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiographs | At 3-, 6- and 12-months post-operatively, subjects will undergo radiographic examination of their affected knee (standardized AP and lateral views) for analysis of tibial tunnel parameters. Radiographic analysis will be conducted by a single orthopaedic surgeon/fellow/resident blinded to subject group and clinical examination results. Parameters to be recorded and analyzed according to a standardized method: tibial tunnel diameter (max/min). We will also look for: Evidence of lysis in the tunnel and changes in morphological features of tunnel over time | 12 months post op | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ACL Quality of Life Scores | Completed at 3-, 6- and 12-months post operatively for subjective outcome measure. | 12 months post op | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tibial tunnel widening, Interference screws