Knee Medial Compartment Contact Pressure Increases With Release of the Type I Anterior Intermeniscal Ligament

Abstract

Background: The anterior intermeniscal ligament of the knee is at risk during knee arthroscopy, anterior cruciate ligament reconstruction, and tibial nail insertion.

Hypothesis: Release of the anterior intermeniscal ligament, in knees with type I ligaments, will result in altered contact pressures in the medial compartment.

Study Design: Controlled laboratory study.

Methods: Five fresh-frozen human cadaveric knees with intact type I anterior intermeniscal ligaments were chosen for testing in a modified MTS machine from 0° to 60° of flexion under 2 conditions: (1) intact and (2) after sharp sectioning of the anterior intermeniscal ligament. Measurements were made using inframeniscal contact pressure sensors covering the medial compartment. Poststudy analysis was done in 10° increments between 0° and 60° of flexion, looking at peak contact pressure and the amount of contact area seeing pressure.

Results: Sectioning of the anterior intermeniscal ligament caused a statistically significant increase in the peak pressure at 20°, 30°, 40°, and 50° of knee flexion. The largest change occurred at 40° of knee flexion, when the peak pressure increased by 27.5% (3.68 MPa to 4.69 MPa). Contact area decreased, although this difference was not statistically significant.

Conclusion: Release of the anterior intermeniscal ligament results in increased peak contact pressures in the medial compartment of the knee.

Clinical Relevance: Care should be taken to avoid sacrifice of this ligament during surgery.