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

Subtalar distraction bone-block arthrodesis for malunited calcaneal fractures was performed in 31 patients (26 men, five women), with a mean age of 38.5 years. The mean time from injury to arthrodesis was 36 months. There were no cases of nonunion. One patient had an early dislocation of the bone block requiring a repeat arthrodesis, and one had a soft-tissue infection. The mean AOFAS hindfoot score improved significantly from 23.5 before operation to 73.2 at a mean follow-up of 33 months (p > 0.001). Compared with the unaffected side, the talocalcaneal height was corrected by 61.8%, the talus-first metatarsal axis by 46.5%, the talar declination angle by 38.5% and the talocalcaneal angle by 35.4%. Dynamic pedobarography revealed a return to normal of the pressure distribution during roll-over and a more energetic gait. The distribution of local transfer of load correlated well with the AOFAS score. The amount of correction of the heel height correlated with a normal pattern of pressure transfer on the heel (p < 0.05)

This retrospective study analyses the results of subtalar bone block distraction arthrodesis used in the treatment of late complications of calcaneal fractures, acute severely comminuted fractures, nonunion (and malunion) of attempted subtalar arthrodeses, avascular necrosis of the talus, and club-foot deformity. Of 39 patients (41 feet) who had this procedure, 35 (37 feet) returned for follow-up after a mean of 70 months (26 to 140). There were 24 men (25 feet) and 11 women (12 feet) with a mean age of 41 years (16 to 63). Each completed a standardised questionnaire, based on the hindfoot-scoring system of the American Orthopaedic Foot and Ankle Society and were reviewed both clinically and radiologically. Of the 37 operations, 32 (87%) achieved union. The mean hindfoot score (maximum of 94 points) increased from 21.1 points (8 to 46) preoperatively to 68.9 (14 to 82) at the final follow-up. The mean talocalcaneal and calcaneal pitch angles were 20.5° and 4.9° before operation, 25.9° and 8.3° immediately after, and 24.6° and 7.7° at the final follow-up, respectively. The mean talar declination angle improved from 6.5° (−10 to 22) before operation to 24.8° (14 to 32) at the final follow-up. The mean talocalcaneal height increased from 68.7 mm before operation to 74.5 mm immediately after and 73.5 mm at the final follow-up. Of the 37 arthrodeses available for review, 32 were successful; 29 patients (30 arthrodeses) were satisfied with the procedure. Minimal loss of hindfoot alignment occurred when comparing radiographs taken immediately after operation and at final follow-up