Load-to-Failure, Contact Area and Contact Pressure of Three Rotator Cuff Repair Methods: A Comparative Biomechanical Analysis Josianne Lépine and Frédéric Balg, MD, FRCSC Department of Orthopaedic Surgery, Université de Sherbrooke In collaboration with Denis Rancourt, PhD, Ève Langelier, PhD, and Nicolas Huppé, MSc Department of Mechanical Engineering, Université de Sherbrooke July 4 th, 2009 – COA Annual Meeting Disclosures : DePuy supplies, FRSQ training award

1- Transosseous 2- Double-row

3-Tendinous tension band Time and cost Less pulling forces on the anchors Anchors fixed laterally into cortical bone Convert traction into compression Better decortication possible

1 - Maximal load tolerated before failure 2 – Tendon-to-bone contact area 3 – Tendon-to-bone contact pressure Hypothesis for all three : Tension band = Double-row > Transosseous

Sawbones ® Load applied at 135° 135 °

Initial immobilization Better indicators of healing Cadaveric shoulders Pressure-sensitive film Load of 12kg applied at 80° 80 °

The tension band suture technique has a lower load to failure. The tension band suture technique has a significantly lower contact area and contact pressure. The double-row anchor suture technique has significantly higher contact area and contact pressure than the transosseous sutures.

Special thanks to : Dr Frédéric Balg - Denis Rancourt - Ève Langelier - Nicolas Huppé The anatomy laboratory - Denis Bisson - Claudia Beaulieu - Elizabeth Tanguay