Proximal fibular osteotomy (PFO) is a simple, easy and cheap procedure consisting of removing a 10 mm piece of fibula 6 to 9 cm below the fibular head. Proximal osteotomy of the fibula weakens the lateral fibular support and leads to a correction of the varus deformity and provides a widening on the medial joint space. Unicondylar knee arthroplasty (UKA) is intended to treat isolated medial compartment arthritis. However, knees with a varus deformity and tight medial joint space might cause both technical difficulties and poorer outcomes. A 68-year-old female with complaints of pain on the medial side of both knees for more than two years underwent bilateral UKA. While inserting the trial meniscal bearing was not easy due to the varus tight knee, at that stage, instead of performing a deeper cut, a PFO procedure was considered which provided widening of the medial joint space. We report, to our knowledge, the first simultaneous application of these two procedures. Despite being a single case with very short term results, our results suggest that the combination of PFO and UKA may reduce the loads over the implants on the medial compartment based on the widening of the joint space and varus deformity correction.