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

• Spring ligament is the primary supporting structure against planovalgus deformity.
• We examined 21 cadaveric specimens in a standardised and reproducible manner.
• Mean lateral translation increased most significantly when spring ligament released.
• Neutral heel lateral push test can determine spring ligament integrity.

IntroductionThe 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.MethodWe 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.ResultsIn 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.DiscussionThe 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.