The Correlation of Tunnel Position, Orientation and Tunnel Enlargement in Outside-in Single-Bundle Anterior Cruciate Ligament Reconstruction.

Purpose: Tunnel widening after anterior cruciate ligament (ACL) reconstruction is a frequently described phenomenon. The possible etiology is multi-factorial with some mechanical and biological factors. Among those, we intended to determine the relation between the location and orientation of the femoral tunnel and the femoral tunnel enlargement after outside-in single-bundle ACL reconstruction.