Correction of pseudoinstability and tibial malalignment by re-establishment of the pretraumatic tibial axis. Posttraumatic valgus malalignment accompanied by pseudoinstability. Infections, significant inhibition of movement and multidirectional ligament instability. Standard anterolateral approach to the proximal tibial head. Lateral open wedge high tibial osteotomy above (supra) the tibiofibular joint and opening until the pseudoinstability of the lateral collateral ligament is levelled. Partial weight bearing for 4weeks, after radiological control full body weight loading is allowed. Implant removal after full bony consolidation. There is limited evidence in the current literature but the available results show good results in 70% of the cases in long-term follow-up.