[Lisfranc arthrodesis after malunited fracture healing]

The causes of residual deformity with posttraumatic painful arthritis after tarsometatarsal (Lisfranc) fracture-dislocation with the need for correctional arthrodesis are in our experience (22 cases over 5 years) overseen injuries in one third, closed reduction and immobilisation or inadequate fixation technique with K-wires in another two thirds of cases. Foot malalignment and residual instability is assessed with weight-bearing radiographs of both feet, adduction/abduction stress films and CT scans for complex deformity. Correction is carried out via two longitudinal dorsal incisions, strict epiperiosteal preparation and debridement of the Lisfranc joint of all remaining cartilage, sclerosis and fibrous tissue. Reorientation begins, in the same manner as primary open reduction, with anatomical alignment of the second metatarsal base to the second cuneiform. Defects are filled with autologous bone grafting, stable fusion can be achieved with 3.5 mm cancellous compression screws. Full weight bearing is allowed in a modelled plaster shoe for 6 to 8 weeks. The functional medium-term results are convincing with 15 of 17 patients seen after 13 months of follow-up working full time. The Maryland Foot Score improved from 38.9 to 76.8 points in these patients.