Characterization of a Bipartite Medial Cuneiform: Micro-CT and Anatomical Study

Abstract

DALMAU-PASTOR, M.; VEGA, J.; BALTASAR-SÁNCHEZ, A.; SLIMANI, L.; BELINHA, J.; GONZÁLEZ S. Á. & MANZANARES, M. C. Characterization of a bipartite medial cuneiform: Micro-CT and anatomical study. Int. J. Morphol., 36(4):1372-1377, 2018. SUMMARY:A bipartite medial cuneiform is an anatomical variant consisting in a horizontal division of the bone. Previous descriptions of the joint type, obtained from archaeological material or clinical reports, are unclear. This study was conducted in a fresh-frozen left foot, which allowed studying the morphology of the ligaments after anatomical dissection. In addition a Micro-CT analysis was performed to elucidate the osseous structure supporting the articular surfaces. A complex ligamentous system was found between the two halves of the bipartite medial cuneiform. Two articular surfaces were observed between the two components. Hyaline cartilage was observed at the posterior surface, while fibrous tissue was found at the anterior surface. Micro-CT analysis revealed different osseous structures for each articular surface, thus proving the existence of two joint types. The finding of a bipartite medial cuneiform in a fresh-frozen specimen allowed us to perform an analysis of the soft-tissues and articular surfaces that shows the presence of hyaline cartilage and articular ligaments in the diarthrodial joint as well as the fibrous component of the synfibrosis. Micro-CT analysis further reinforces our morphological findings. Our results prove that two different joint types exist, which could help explaining the disparity of descriptions in the literature. DALMAU-PASTOR, M.; VEGA, J.; BALTASAR-SÁNCHEZ, A.; SLIMANI, L.; BELINHA, J.; GONZÁLEZ S. Á. & MANZANARES, M. C. Characterization of a bipartite medial cuneiform:Micro-CT and anatomical study. Int. J. Morphol., 36(4):1372Morphol., 36(4): -1377Morphol., 36(4): , 2018

Bipartite Medial Cuneiform: A Forgotten Source of Midfoot Pain – Case Report and Review of the Literature

“…BMC is a rare congenital anatomical variation occurring at the Lisfranc joint, representing a malsegmentation defect caused by non-fusion phenomenon of the two primary ossification sites of the medial cuneiform [3]. In the majority of the cases the bipartition displays a horizontal pattern, dividing the medial cuneiform in a plantar and dorsal segment [7]. The dorsal segment frequently presents lesser dimensions [1].…”

“…According to the literature, conservative treatment is considered the first line of treatment including non-weight bearing, custom-design orthosis, nonsteroid anti-inflammatory drugs, and image-guided corticosteroid injection [6][7][8][9]. Classically, surgical treatment is reserved for the cases that do not respond to conservative measures and can include fusion or excision procedures.…”

“…BMC incidence is estimated to be between 0.1% and 2.4% in the general population [3][4][5].In the majority of the cases, BMC is asymptomatic and diagnosed as an incidental imaging finding. Awareness of this anatomic variant may become clinically relevant when evaluating a patient with midfoot pain following both acute trauma or in the setting of chronic and insidious midfoot complaints [1].According to the literature, conservative treatment is considered the first line of treatment including non-weight bearing, custom-design orthosis, nonsteroid anti-inflammatory drugs, and image-guided corticosteroid injection [6][7][8][9]. Classically, surgical treatment is reserved for the cases that do not respond to conservative measures and can include fusion or excision procedures.…”