[The direct, dorsal approach to the treatment of unstable tibial posteromedial fracture-dislocations]

Abstract

The surgical treatment of highly unstable tibial posteromedial fracture-dislocations (medial split fracture,Moore type I) is demanding and may cause significant problems. The anterior and the posteromedial approach require detachment of the medial capsuloligamental structures or arthrotomy of the knee joint. Neither of these operative techniques allow the optimal posterior positioning of the buttress plate in order to prevent caudal dislocation of the fragment during knee flexion. The published posterior approaches to the proximal tibia allow appropriate positioning of the anti-glide plate. However, these surgical exposures involve transsection of the semi-membranous and popliteal muscles as well as the partial dissection of the medial gastrocnemius muscle. We present a direct posterior approach and an operative treatment of medial split fractures with open reduction and internal fixation in a prone position. This position simplifies the reduction of the posteromedial fragment by hyperextension and axial traction, as well as osteosynthesis with lag screws and the placement of the buttress plate (radial T-plate). The surgical exposure requires minimal soft tissue dissection. The inferior spike of the fragment can be visualized by partial subperiosteal detachment the popliteal muscle,whereas the medial gastrocnemius muscle and the semi-membranous muscle are preserved. Due to the voluminous subcutaneous tissue in the posteromedial tibial aspect, the closure of the skin incision over the medial gastrocnemius muscle can be performed without difficulty. Three cases of tibial posteromedial fracture-dislocation were treated by the direct posterior approach in a prone position in January and February 2002. The present report shows that the direct posterior surgical technique allows optimal exposure, reduction and internal fixation of medial split fractures of the tibial plateau with minimal trauma.