Stabilizing effect of the tibiocalcaneal fascicle of the deltoid ligament on hindfoot joint movements: an experimental study.

The tibiocalcaneal fascicle of the deltoid ligament was studied in 10 lower leg amputation specimens to evaluate its stabilizing effect on movement in the tibiotalocalcaneal joint complex and the talocalcaneal joint complex. Cutting of the fascicle resulted in minor numerical increases in movement in all three planes in the tibiotalocalcaneal joint complex as well as in the talocalcaneal joint complex. The maximum median increase in the tibiotalocalcaneal joint complex was 6.1 degrees in abduction, whereas the maximum median increase in the talocalcaneal joint complex was 3.6 degrees in abduction. However, the percentage of increase in the total range of movement in a single plane was large for abduction-addition in both the tibiotalocalcaneal joint complex and the talocalcaneal joint complex, at 28% and 31%, respectively. The largest percentage of increase, 40%, was found in the total range of plantarflexion-dorsiflexion in the talocalcaneal joint complex. Our data suggest that the tibiocalcaneal fascicle is an important stabilizing structure of abduction, external rotation, and plantarflexion movements in the tibiotalocalcaneal joint complex, especially in the talocalcaneal joint complex.