Neutral heel lateral push test: The first clinical examination of spring ligament integrity.

INTRODUCTION: The spring (calcaneonavicular) ligament is an intricate multiligament complex whose primary role is to stabilise the medial longitudinal arch and head of talus. Clinical suspicion of a spring ligament injury in isolation is roused when persistent medial midfoot pain is present with associated pes planus following trauma.

METHOD: We undertook a cadaveric study on 21 specimens to assess the use of a neutral heel lateral push test to examine the spring ligament in a standardised procedure, measuring lateral translation with graduated antegrade and retrograde defunctioning of surrounding structures and the spring ligament.

RESULTS: In all specimens, a significant displacement occurred on incision of the spring ligament regardless of order of dissection. The degree of displacement increased by an insignificant amount as surrounding structures were incised at each incremental force applied.

DISCUSSION: The neutral heel push test is the first clinical examination to be described to determine integrity of the spring ligament complex. Our study objectively demonstrates that lateral displacement in relation to the mid and hind-foot is influenced most significantly by the integrity of the spring ligament and to a lesser extent by tibialis posterior and flexor digitorum longus.