5 revisions were performed; 2 for stiffness (1 tibial component, 1 insert), 2 for stress fractures (tibial component only) and 1 insert fracture. 3 of these cases required further surgery following their first revision (1 fusion for deep infection, 1 insert exchange for edge loading and one arthoscopic debridement plus calcaneal osteotomy for painful varus deformity). There were no primary revisions for aseptic loosening or deep infection. 3 radiographs demonstrated non-progressive lucent lines behind the tibial component. Further surgery was required in 8 other ankles (6 calcaneal osteotomies and 2 arthroscopic debridements). Complete correction of pre-operative deformity was ultimately achieved in all but 4 ankles. The mean postoperative American Orthopaedic Foot and Ankle Society Score was 77.
6 revisions (13%) were performed in Group A (5 of these related to instability – all preoperatively varus of >
20 degrees). 10 revisions (8%) were performed in Group B (2 related to instability). 6 ankles underwent intra-operative deltoid release and 6 had pre or post-operative calcaneal osteotomy. Only one of these required revision for instability. 4 ankles underwent post-operative lateral ligament reconstruction. These ankles all failed due to instability. The mean postoperative American Foot and Ankle Society score in Group A was 85, compared to 78 in Group B.