Abduction Stress and AP Weightbearing Radiography of Purely Ligamentous Injury in the Tarsometatarsal Joint

Twenty volunteers (40 feet) with no prior foot injury underwent standardized abduction stress and standing AP radiographs. Subsequently, the Lisfranc and dorsal tarsometatarsal ligaments in nine feet from cadavers were sectioned in a varying sequential manner, and interval standardized radiographs of abduction stress and AP simulated weightbearing were obtained. On abduction stress radiographs in 39 of 40 feet of volunteers and nine of nine feet of cadavers before sectioning, a line tangential to the medial aspect of the navicular and medial cuneiform (medial column line) intersected the base of the first metatarsal. Combining the sectioning of the Lisfranc and dorsal tarsometatarsal ligaments produced a disruption of the medial column line in all feet from cadavers. Disruption of this medial column line may be a simple and valuable diagnostic tool for determining significant ligamentous injury to the tarsometatarsal interval.