Acta Orthop Scand. 1963;33:320-328
Barneft, Napier & Hicks showed that the axis of the ankle joint passes obliquely in relation to the sagittal plane of the foot. This means that the foot moves in the ankle joint like a poorly mounted wheel, it swerves from side to side. Normally the swerve is compensated for in the talotarsal joints, but when subtalar arthrodesis has been performed there is no compensation. The size and variability of the lateral swerve of the heel in a plantar flexion corresponding to a shoe heel of 4 cm is demonstrated. In all the cases demonstrated the heel swerves in the varus direction on such plantar flexion, if it does swerve at all.
Varus is endured less easily than valgus. The conclusion therefore is that in adjusting a subtalar arthrodesis on the operating table consideration must be given to the height of the heel the patient is to use (e.g. owing to shortening of the extremity). This is done by adjusting the subtalar arthrodesis with the ankle joint in the pointed foot position which the height of the heel requires, and not at right angles between leg and sole of foot. (Reprinted by permission of Taylor & Francis Ltd., http://www.tandf.co.uk/journals.)