Surgical strategies and clinical outcomes of Pilon fractures caused by different injury mechanism

Abstract

Objective To explore the surgical strategies and clinical outcomes of Pilon fractures caused by different injury mechanisms. Methods From February 2009 to July 2015, 64 patients with Pilon fractures were retrospectively analyzed in this study. These patients were divided into five groups (varus, valgus, back stretch, plantar flexion and vertical compression) according to the injury mechanisms and the imaging findings of anatomic features.There were 18 patients in varus, valgus group 15 patients, back stretch group 12 patients, 10 patients of plantar flexion group, vertical compression group 9 patients. Sixty-four patients were treated with internal fixation. By adopting the corresponding approaches on the injury mechanism, there were used posterormedial approach 6 patients, middle approach 9 patients, anterolateral approach 12 patients, posterolateral approach 18 patients, anteromedial approach 19 patients; the buttress plate was placed on the compression fracture of distal tibia. Six months after surgery, the reduction quality of the joint surface was evaluated by Burwell-Charnley's radiological evaluation system. Twelve months after surgery, the function of ankle joint was assessed by utilizing American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score system, and the total effect was evaluated by improved Baird-Jackson score system. Results Sixty-four cases were followed up for 15-48 months(average 31 months). The average healing time ranged from 13.0 to 18.0 weeks [mean (15.54±0.2) weeks ]. Mean AOFAS score was 85.82. Radiological evaluation of curative effect: excellent in 52 patients, good in 12 patients. The postoperative reductions were as follows: 9 anatomic, 8 good, and 1 fair in varus group; 6 anatomic, 7 good, and 2 fair in valgus group; 7anatomic, 4 good, and 1 fair in back stretch group; 5 anatomic, 3 good, and 2 fair in plantar flexion group; 2 anatomic, 4 good, and 3 fair in vertical compression group. Postoperative follow-up of ankle function, AOFAS score and radiological evaluation of curative effect were 87.52±0.2, excellent 15 patients, good 3 patients in varus group; 86.41±0.1, excellent 12 patients, good 3 patients in valgus group; 85.34±0.4, excellent 10 patients, good 2 patients in back stretch group; 85.25±0.1, excellent 8 patients, good 2 patients in plantar flexion group; 84.63±0.3, excellent 7 patients, good 2 patients in vertical compression group. In group varus, 1 patient developed superficial wound infection and 1 patient epidermal necrosis; In group valgus, 3 patients developed superficial wound infection, 1 patient deep wound infection; In group back stretch 1 patient developed superficial wound infection; In group plantar flexion 1 patient developed traumatic arthritis; In group vertical compression 1 patient deep wound infection, 2 patients delayed union of bone, 2 patients developed traumatic arthritis. Conclusions Different injury mechanisms will result in different types of Pilon fractures. Different strategies should be used according to the characteristics of fracture with the buttress plates being placed on compression fracture of distal tibia to achieve better clinical outcomes. Key words: Tibial fractures; Pilon fractures; Damage mechanism; Surgiclal procedures; Treatment outcome