Classification of midfoot deformities in Charcot neuroarthropathy

Background. Midfoot pathology accounts for 60-70% of all deformities in diabetic Charcot neuroarthropathy. However, the available classifications of this pathology are few and have certain disadvantages.

The aim of the study — to analyze X-rays of patients to investigate the displacement patterns of the midfoot bone and joint structures in Charcot neuroarthropathy, and, based on the identified displacement trends, to develop an anatomical and radiological classification of midfoot deformities.

Methods. A retrospective analysis was performed on the foot X-rays of 416 patients (436 feet) with midfoot pathology in Charcot neuroarthropathy. Of these, 233 X-rays were provided by inpatient hospitals, and 203 — on an outpatient basis. Only X-rays taken in anteroposterior and lateral views were included in the analysis. We assessed the alignment of bones within the foot joints, the extent of destruction, and the direction of the displacement of bony structures.

Results. The following types of lesions are identified. 1A — involvement of the navicular bone and talar head with the preservation of the lateral column anatomy. 1B — simultaneous involvement of the talonavicular and calcaneocuboid joints. 1C — subluxation or dislocation of the talonavicular joint with transition to the lateral parts of the tarsometatarsal joint with plantar dislocation of the cuboid bone and preservation of anatomical integrity in the calcaneocuboid joint. 1D — complete displacement of the navicular bone with the dislocation of the talonavicular, naviculocuneiform and tarsometatarsal joints. 2 — deformation (subluxation, dislocation, fracture-dislocation) of the naviculocuneiform joint, with involvement of the lateral column in the metatarsocuboid joint and flattening of the medial column. 3 — isolated involvement of the Lisfranc joint. 4A — isolated involvement (subluxation or dislocation) of the first cuneometatarsal joint without visible deformity in the affected area. 4B — dislocation of the medial naviculocuneiform and medial cuneometatarsal joints with the displacement of the medial cuneiform bone relative to the other foot bones. 5 — varus deformity of the foot with fractures of the metatarsal bones.

Conclusion. A new classification of Charcot midfoot lesions is intended to guide the selection of key reconstructive surgical interventions for this pathology.