Simple screw fixation for calcaneal fractures: 60 cases with preoperative computed tomography analysis

Purpose of the study In accordance with the conclusions established at the SOFCOT symposium in 1 988, we propose surgical treatment of displaced fractures of the calcaneus with screw fixation after reduction. We developed an original classificatio n system of 3D computed tomography images which allows a precise descriptio n of the fractures and guides joint and calcaneal body reconstructions. The purpose of this work was to provide a precise analysis of operated fractur es in order to identify prognostic factors and validate use of exclusive sc rew fixation for calcaneal fractures. Materials and methods This series included 60 operated articular fractures of the calcaneus. The Utheza classification was: 12 vertical, 7 horizontal with 1 fracture line, 3 horizontal with 2 fracture lines, 23 mixed with 1 fracture line and 15 mi xed with 2 fracture lines. 3D computed tomography evidenced the fundamental fracture lines and their anterior extension. Fixation was achieved with on e screw inserted in a transverse position under the posterior facet and one oblique screw from the greater tuberosity to the sustentaculum tall. The m edial and lateral Bohler angles were measured on plain x-rays. The analysis included search for a double line on the posterior talocalcaneal facet, se condary body displacement, the position of the oblique screw and the degree of posttraumatic subtalar wear. The clinical criteria established in the 1 988 SOFCOT guidelines were recorded. Analysis of variance, Pearson and Spea rman coefficients, and RIDITS analysis (the most powerful method available for evidencing a relationship between two qualitative variables one of whic h is ordinal) were used to search for prognostic elements and correlations. Results No severe complications were encountered with the wide lateral access. A ne gative medial Bohler angle was significantly correlated with an additionnal posterior facet line. A mean 80 p. 100 reduction in the towering of the me dial part of the posterior facet and an 87 p. 100 reduction in lateral pivo ting were achieved irrespective of the type of fracture. Minimal secondary body displacements were significantly related to anchorage of the oblique s crew outside the sustentaculum tall. Functional outcome was satisfactory (v ery good + good + average) in 75 p. 100 of the cases and physical outcome i n 50 p. 100 (very good + good) irrespective of the type of fracture. Outcom e was significantly correlated with reduction in the Bohler angle, double l ines on the posterior facet, secondary displacement and osteoarthritis. Discussion The 3D analysis of posterior facet fractures using our classification was u seful in guiding reconstruction with correction of the medial lowering and the lateral pivoting. A negative medial Bohler angle was a factor of poor p rognosis: more posterior facet lines, joint wear and deterioration of the f unctional and physical outcome. Good outcome required good reduction of the Bohler angle and good anchorage of the oblique screw in the sustentaculum tall. Good subtalar mobility was associated with pain relief. Uniform anato mic and pathologic classifications and precise analysis criteria are needed for pertinent comparison between series and proper definition for indicati ons for first-line reconstruction-arthrodesis. Conclusion Measurement of the medial Bohler angle improves the sensitivity of revision criteria for articular fractures of the calcaneus. Screw fixation has prov en its reliability.