[Lapidus arthrodesis].

The tarso-metatarsal 1 joint (TMT-I) arthrodesis is a treatment option or moderate to severe hallux valgus (HV) deformities. Instability of the TMT1 joint is still a debatable indication. Using stable osteosynthesis techniques allows early postoperative weight bearing. Plantar plating combined with a lag screw is the biomechanical most stable construct. An additional intermetatarsal screw can improve the horizontal stability. Clinical results are good and radiological parameters stay constant, even in the long term.