One-stage lengthening using a locked nailing technique for distal femoral shaft nonunions associated with shortening

Objective: To assess the effectiveness of a one-stage lengthening using a locked nail technique for the treatment of distal femoral shaft nonunions associated with shortening. Design: Retrospective. Setting: University hospital. Patients and Methods: During a 6-year period, 36 distal femoral shaft nonunions associated with shortening (>1.5 cm) were treated by the one-stage lengthening technique. Indications for this technique were distal femoral shaft aseptic or quiescent infected nonunions, 1.5-5 cm shortening, and a fracture level suitable for the insertion of two distal locked screws. The surgical technique involved skeletal traction using the femoral condyle, local debridement, lengthening by less than or equal to 4 cm aided by a laminar spreader, insertion of a static locked nail, and grafting of corticocancellous bone. Mize's classification for clinical function was used for final patient evaluation. Results: A total of 32 nonunions were followed-up for at least 1 year (median 3.8 years; range 1.2-6.9 years), and 29 fractures heated. The median union period was 4.5 months (range 3-6 months). Three fractures persistently failed to heal. One was treated successfully with exchange nailing, and the remaining two patients were followed annually and had no symptoms. At the latest follow-up, all 32 patients had achieved a satisfactory outcome. The average lengthening was 2.5 cm (range 1.5-3.5 cm). Conclusions: one-stage lengthening using the locked nailing technique to treat distal femoral shaft nonunions associated with shortening can achieve a high success rate and low complication rate. The key to successful treatment is the patient's complete cooperation with strictly protected weight bearing until the fracture has healed.