The spring ligament meniscus: an anatomical study

M.L.T. Jayatilaka, A. Bond, A. Fisher, M. Philpott, L.-A. Amber, L. Fisher, A. Molloy, L. Mason

Introduction: An articular facet composed of fibrocartilage has previously been described in the superomedial spring ligament. Our aim in this study was to analyse this fibrocartilage structure, assessing its association with the other aspects of the acetabular pedis.

Methods: We examined 14 cadaveric lower limbs that had been preserved for dissection at the Human Anatomy and Resource Centre at Liverpool University in a solution of formaldehyde. The spring ligament was approached from the superior direction. The talus was disarticulated and high-resolution images were taken of the acetabular pedis. ImageJ software was used to calculate the surface area of the spring ligament articular facet (SLAF).

Results: Dissection was performed on 14 specimens, 4 left and 10 right. All specimens were morphologically normal with no evidence of previous surgical intervention. The mean area of the SLAF was140.79mm² (95% Confidence intervals 125.31, 156.27), equivalent to the size of the medial facet of the calcaneum. The SLAF was attached anteriorly to the navicular and posteriorly to the sustentaculum, orientated to not only bear weight in stance phase with the load of the talar head but also in propulsive phase, bearing weight between the navicular and the sustentaculum tali when the foot was in inversion. The SLAF was composed of fibrocartilage with a smooth superior articular surface.

Conclusion: The SLAF is an important weight bearing structure in all phases of gait. More work needs to be done in its role in the biomechanics of the foot and the options for reconstruction in pes planus deformity.