The Proximal Tibia Less Invasive Stabilization System (LISS PLT) is an internal fixator for the treatment of proximal tibial fractures according to the principles of "Minimally invasive surgery". From July 1998 to August 2000 22 fractures were treated in our clinic with the new Proximal Tibia LISS and the prospective course of healing was documented. The period of follow-up was 12 months. The inclusion criteria were defined as proximal tibial shaft fractures and intraarticular proximal tibial fractures of all degrees of severity. A total of 15 proximal medial and lateral tibial plateau fractures (AO 41) and 7 metaphyseal fractures were treated (AO 42), seven of these fractures presented with open soft tissue damage. The average age of the patients treated was 42 years. With a follow-up rate of 91% (2 patients lost to follow-up), definite consolidation of the fracture was seen in 19/20 cases. In one patient, the fracture had only been partially bridged and secondary bone grafting was performed. Radiologically, there was one case of a varus malalignment of 6 degrees, in two further cases there were valgus malalignments of 5 degrees and 7 degrees at the time of surgery. The other cases all healed in correct alignment. In one case, the implant became loose on the distal shaft and was stabilized again using bicortical screws. In a case with type IIIB soft tissue damage, a soft tissue infection became manifest, but healed uneventfully after a revision operation with the implant in situ.