ABSTRACTBiomechanical studies have shown increased rota-

tional stability with double bundle compared to singlebundle ACL reconstruction. The aim of this study was toevaluate the difference in rotational kinematics after sin-gle and double bundle ACL reconstruction.

40 Subjects undergoing ACL reconstruction wasprospectively randomized to DB (n�20) and SB(n�20) groups. Exclusion criteria included meniscalpathology, collateral ligament instability, previous in-jury and previous surgery. All surgery was performedby one surgeon using Semitendanosis and gracilis asgraft and Endobutton and BioRCI screw as fixation.Demographics data were comparable between the 2groups. Passive laxity was measured by determiningthe 6-degree-of-freedom position and orientation ofthe femur and tibia under a known torsional load usingMRI. Each subject underwent 3 studies one on theuninjured knee that served as the control one preoperative and one post operative.Results: Rotational stability increased after ACL injuryand improved after surgery but not to normal. There wasno statistical difference between single and double bun-dle Reconstruction in restoring rotational stability. APtranslation in the medial compartment was also measuredduring rotational loading and there was a statistical dif-ference between DB and SB reconstruction with DBbeing superior. The axis of rotation was different for DBand SB reconstruction although this was not statisticallysignificant.

The subjective IKDC score was the same for bothgroups but the objective IKDC score was significantlybetter for the DB groupConclusions: Our study shows that although there wasno difference in the overall rotational stability betweensingle and double bundle ACL reconstruction, medial APtranslation and rotational axis differences might explainthe better objective score. Further studies are necessaryto determine if abnormal translation in the medial com-partment lead to increase risk for OA.

Paper 4: Prospective randomized study on DoubleBundles ACL Reconstruction (Out-In technique) ver-sus Single Bundle (STG) ACL Reconstruction (TransAntero-Medial Portal) LUIGI A. PEDERZINI, MD, ITALY,PRESENTING AUTHOR

MASSIMO TOSI, ITALY

MAURO PRANDINI, ITALY

LUIGI MILANDRI, ITALY

FABIO NICOLETTA, ORTHOPAEDIC SURGEON, ITALY

ANDREA DAVIDE COSSIO, ORTHOPAEDIC SURGEON, ITALY

ABSTRACTPurpose: The purpose of this study is to compare in aprospective randomized study, the clinical outcome andradiographic results between Double Bundle Out-Intechnique and Trans Antero-Medial portal Single Bundle(STG) technique in a 2 years follow-up.Materials and Methods: From March 2005 to March2006, 70 patients were operated and involved in a pro-spective randomized clinical study, 35 of these had ananatomical ACL reconstruction using Out-In technique(group A) and 35 had Trans Antero-Medial portal SingleBundle technique (STG 4 strands) (group B).

In Both the group anatomical insertional areas wereevaluated and measured arthroscopically, notch-plastywas not performed and patients with associated meniscal,peripheral lesions and condral problems were excluded.

In the group A, the tunnels were drilled over theanatomical areas in a convergent Out-In manner, and thenew bundles fixed by 4 absorbable screws at femoral andtibial levels. In the Group B the femoral tunnel was donedrilling through medial portal in order to obtain a newinsertion at 10/2 o’clock. All the cases were evaluated byan external observer: ROM evaluation was done at 1, 3,6 and 12 months, IKDC score and a standard X-Ray wasperformed at 24 months.Results: The average ROM at 1 month was 0°-125° inthe Group A, and 0°-100° in the Group B and respec-tively 0°-135 and 0°-125 at 3 months, and not significallydifferent at 12 and 6 months.

The IKDC score at 24 months follow-up evidenced82% grade A, 10% grade B and 8% grade C for group A,while group B showed 76% grade A, 14% grade B, 10%grade C. The residual pivot shift (glide) was 4% in groupA and 8% in group B. Standard X rays at 24 monthspost-op showed a mild enlargement for both the groupsA and B obviously in respect of the initial tunnel diam-eters.Conclusions: Out–in technique in anatomical doublebundle ACL reconstruction gave us better results com-pared to Trans Antero-Medial portal Single Bundle ACLreconstruction in early ROM, A-P stabilization and inresidual pivot shift test.

Paper 5: Prospective Clinical Comparisons of Ana-tomic Double Bundle Versus Single Bundle AnteriorCruciate Ligament Reconstruction Procedures in 328Consecutive Patients EIJI KONDO, MD, PHD, JAPAN, PRE-SENTING AUTHOR

NOBUTO KITAMURA, MD, JAPAN

SHIN MIYATAKE, MD, JAPAN

KAZUNOBU ARAKAKI, MD, JAPAN

YOSHIE TANABE, RPT, PHD, JAPAN

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