Subtalar fusion after conservative or operative treatment of intraarticular calcaneus fracture

In a long-term follow-up we evaluated 40 patients out of 55 (73%) with a su btalar fusion. The operations took place from 5/84 to 5/91. In all cases th e indication for the fusion was a post-traumatic arthritis after an intra-a rticular os calcis fracture. The evaluation of the overall results was carr ied out with three different scoring systems: a. The Hannover Scoring Syste m. b. The Outcome-questionnaire, rating patient's complaints and the functi onal status based on the severity-symptom scale and functional status descr ibed for Carpaltunnel-syndrome by Levine et al. c. The clinical rating syst em (CRS) described by Kitaoka et al. The statistical evaluation was perform ed by analysis of variance (ANOVA). Level of significance was based on P = 0.05 and calculation of Pearson's correlation coefficient. The Os calcis fr acture was the cause for the subtalar arthritis in all 40 patients (33 male s and 7 females). The primary treatment of the calcaneal fracture was conse rvative (cons.) using a plaster in 23 patients (57.5%), while 17 patients ( 42.5%) underwent open reduction and plate fixation (op.). The interval betw een trauma and subtalar fusion averaged 3.5 years (3 months to 20 years). T he interval between subtalar fusion and follow-up averaged 5.2 years (4-14 years). The mean age at the time of reexamination was 47 years (26-61 years ). In the present study, complete pain relief could be achieved in 21 (52.5 %; 58% op., 50% cons.) patients. A relevant restriction in the range of mot ion in the ankle joint was found in 26 (65%; 76% op., 58% cons.). In 23 pat ients (62%; 65% op., 59% cons.) the radiological evaluation revealed a grad e 1 degrees arthritis of the ankle joint, in the talonavicular joint in 17 patients (42.5%; 41% op., 45% cons.), and in the calcaneo-cuboid joint in 1 4 patients (35%; 47%., 27% cons.). The statistical analysis revealed a bett er outcome in the operative group compared with the conservative group, alt hough the operated os calcis fractures in the majority were the more severe fracture types. In all evaluation systems a score between 61 and 69 points could be achieved with no significant difference between the operatively a nd conservatively treated groups and between the newly developed questionai re and the clinical-radiological scoring systems. For the questionaire this fulfills the requirements for a reliable outcome evaluation.