Femoral supracondylar malunions associated with varus deformity of the medial femoral condyle and shortening are rare, and all techniques for treatment of this complication reported to date have limitations. A one-stage antegrade locked intramedullary nailing technique to concomitantly treat these combined disorders was performed in 19 consecutive patients. The following procedures were performed: removal of previous implants, supracondylar corrective osteotomy, one-stage lengthening on a fracture table, antegrade static locked intramedullary nail stabilization, and corticocancellous bone grafting. Seventeen patients with malunions received regular followup for a median of 2.4 years (range, 1.1-5.2 years). Sixteen malunions healed with a union rate of 94.1% (16 patients) and a median union period of 4.5 months (range, 3-7 months). Only one nonunion associated with nail breakage occurred (5.9%; one patient) and one deep infection recurred (5.9%; one patient). Both patients recovered after appropriate treatment. All patients had improved knee alignment and function. Antegrade locked intramedullary nailing is an effective technique for one-stage treatment of combined disorders in patients with femoral supracondylar malunions. Complications can be avoided if patients and surgeons are careful during the treatment course. Protected weightbearing until fracture healing is crucial to successful treatment.