The effect of an iliotibial tenodesis on intraarticular graft forces and knee joint motion

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering
• Sports Medicine

Background:

• Lateral extraarticular reconstructions serve as primary or adjunctive procedures for knee rotatory instability.
• Anterior cruciate ligament (ACL) injuries often require intraarticular reconstruction, sometimes augmented with extraarticular techniques.

Purpose of the Study:

• To evaluate the biomechanical impact of an iliotibial band tenodesis when combined with an intraarticular ACL reconstruction.
• To quantify changes in graft forces and knee stability with the addition of a tenodesis.

Main Methods:

• Utilized a cadaveric knee testing system to analyze mechanical effects.
• Tested seven fresh knee specimens under simulated anterior tibial load (90 N) at various flexion angles.
• Measured ligament and graft forces using buckle transducers and joint motion with spatial linkage.

Main Results:

• Adding an iliotibial band tenodesis to an intraarticular ACL reconstruction decreased ACL graft force by an average of 43%.
• When reconstruction was added to a tenodesis, graft forces were 15% lower than reconstruction alone.
• Tenodesis force was less than graft force at extension, but not significantly different at 30-90 degrees flexion.

Conclusions:

• An iliotibial band tenodesis effectively unloads the ACL graft in combined reconstructions.
• This technique offers a potential biomechanical advantage for managing knee rotatory instability.
• Further research may explore clinical outcomes of this combined surgical approach.