Holographic investigations of the human tibiofibular interosseous membrane.

The interosseous membrane contributes to the function of the fibula by neutralizing the freedom of movement in the upper tibiofibular joint and by keeping the fibula from being passive. The main role of the membrane is indicated by its shearing capacity. As a result of dislocation and bending of the tibia (during axial loading), and the passivity of the fibula, the membrane slides in the direction of the leg's axis causing the zone of maximal shearing in its upper central part. This is the principal zone of strain and divides the upper portion of the membrane into the tibial and fibular area. Damage of the upper part of the membrane, perpendicular to the main fiber bundles, causes an irregular deformation of the talus, while complete damage of the membrane unburdens the fibula in load transference by more than 30%. The interosseous membrane is important in the normal function of the lower leg by maintaining the axis of balanced loading of the foot.