EFFECT OF VARIATIONS IN CALCANEOCUBOID FUSION TECHNIQUE ON KINEMATICSOF THE NORMAL HINDFOOT

Calcaneocuboid fusion with lengthening of the lateral column of the fo ot has been advocated as a method of treating flatfoot deformity. This study was designed to determine how the length of the lateral column chosen or the position of the foot selected when performing this fusio n affect hindfoot kinematics in normal cadaver feet. An electromagneti c tracking system was used to monitor the positions of the talus, calc aneus, navicular, and cuboid while the intact cadaver feet were moved passively and then under reproducible loads. Calcaneocuboid fusion was then performed on these feet first with the feet in neutral position and the lateral column of normal length, then lengthened 10 mm or shor tened 5 mm, and then with the lateral column lengthened 10 mm and the feet positioned in plantar flexion and eversion or dorsiflexion and in version. Kinematic measurements were made at each stage using the same loads. Fusing the calcaneocuboid joint with lengthening or shortening the lateral column and the feet in neutral position did not affect hi ndfoot joint motion compared with intact. Changing the position of the foot for fusion, however, resulted in significant decreases in motion in the talocalcaneal and talonavicular joints. Tibiotalar joint motio n was unaffected. This study, therefore, demonstrates that when fusing the calcaneocuboid joint, attention should be paid to maintaining a n eutral position of the foot.