Mid-Term Results of Minimally Invasive Plate Osteosynthesis and Circular External Fixation in the Treatment of Complex Distal Tibia Fractures.

Background: The treatment of pilon tibia fractures is challenging. Anatomical reduction of the joint surface is essential. Excessive soft-tissue dissection may interfere with the blood supply and can result in nonunion. We sought to compare the outcomes of distal tibia fractures treated with medial locking plates versus circular external fixators.

Methods: We retrospectively evaluated 41 consecutive patients with closed pilon tibia fractures treated with either minimally invasive locking plate osteosynthesis (n = 21) or external fixation (EF) (n = 20). According to the Ruedi and Allgower classification, 23 fractures were type B and 18 were type C. Soft-tissue injury was evaluated according to the Oestern and Tscherne classification. Time to fracture union, complications, and functional outcomes were assessed annually for 3 years with the American Orthopaedic Foot and Ankle Society (AOFAS) ankle score.

Results: Mean ± SD values in the plate group were as follows: age, 42.4 ± 14 years; union time, 19.4 ± 2.89 weeks (range, 12-26 weeks); and AOFAS ankle scores, 86.4 ± 2.06, 79.5 ± 1.03, and 77.9 ± 0.80 at 1, 2, and 3 years, respectively. Four patients in the plate group needed secondary bone grafting during follow-up. In the EF group (mean ± SD age, 40.7 ± 12.3 years), all of the patients achieved union without secondary bone grafting at a mean ± SD of 22.1 ± 1.7 weeks (range, 18-24 weeks). In the EF group, mean ± SD AOFAS ankle scores were 86.6 ± 1.69, 82.1 ± 0.77, and 79.7 ± 1.06 at 1, 2, and 3 years, respectively. There were no major complications. However, there were soft-tissue infections over the medial malleolus in five patients in the plate group and grade 1-2 pin-tract infections in 13 patients and grade 3 pin-tract infections in one patient in the EF group. Post-traumatic arthritis was detected in eight plate group patients and seven EF group patients.

Conclusions: Minimally invasive plating and circular EF methods have favorable union rates with fewer complications.