We analysed 42 weight-bearing lateral radiographs of the ankle, 20 of which were from patients with a clinical and plain radiological diagnosis of talocalcaneal coalition (TCC) who subsequently had CT. The remainder were from 22 healthy volunteers with no clinical findings suggestive of hindfoot pathology. Four observers, blinded to the CT findings, independently evaluated the radiographs on two separate occasions. With the 95% confidence interval and using the CT findings as the comparison we calculated the sensitivity, specificity, accuracy, and positive and negative predictive values for the C-sign, and for other signs known to be associated with TCC. Similarly, we also calculated the interobserver and intraobserver reliability for these signs using the kappa statistic. Our results suggest that the C-sign is highly sensitive and specific for TCC. It is an accurate indicator and significantly more reliable than other previously recognised radiological signs of TCC. Features of the C-sign, however, cannot be relied upon to indicate whether the TCC is fibrous or bony

Our aim was to evaluate the results of triple arthrodesis, performed without the use of supplementary bone graft. We carried out a retrospective review of 100 consecutive triple arthrodeses. All the operations had been performed by the senior author (TSS) using a standard technique. Only local bone graft from the excised joint surfaces had been used, thereby avoiding complications at the donor site.

The mean age of the patients at surgery was 58 years (18 to 84). The mean time to union was 5.1 months (3 to 17). There were 75 good, 20 fair and five poor results. There were four cases of nonunion.

Our study has shown that comparable rates of union are achieved without the need for supplementary bone graft from the iliac crest or other donor site.