[Combined tibio-talar and subtalar arthrodesis by retrograde nail in hindfoot rheumatoid arthritis]

Many techniques for ankle arthrodesis have been described. Some are not applicable to patients with severe rheumatoid arthritis (RA) because of osteopenia and deformities. This study describes a new surgical technique for arthrodesis in painful valgus deformity of the hind-foot in advanced rheumatoid arthritis (RA) with severe osteopenia.

The present series included 9 patients. Eleven talocrural and talocalcaneal arthrodeses were performed for degenerative changes secondary to RA involving hind-foot joints. All patients were reviewed after an average follow-up of 6 years. Mean duration of RA was 34 years. All patients had severe osteopenia, including major deformations of the hind-foot in 5 cases.

After removal of talocrural and talocalcaneal articular surfaces using an anterolateral approach, deformities were corrected by removal of an appropriate bone wedge. A Küntscher nail was then positioned in the calcaneal plantar cortical through the plantar surface of the foot and driven proximally into the medullary canal of the tibia through the talus. This nail allowed both deformity correction and fixation. Aftercare required immobilization in a short leg cast. Weight bearing was allowed with the cast approximately 5 weeks after surgery. The ankle was immobilized for 7.5 weeks.

Results showed a 80 per cent fusion rate. Two non-unions occurred (one recurrence of valgus deformity after early nail migration requiring removal of the nail; and the other asymptomatic). A complication occurred in one foot (delayed healing). At follow-up, all patients but one were satisfied with respect to pain relief and residual deformities. Our results are comparable with those of other series and should be considered in the context of severe RA.

This technique of vertical retrograde transarticular nailing allows an easy control of hind-foot deformities correction. Other techniques are preferable in case of solid bone. This technique is an acceptable alternative in advanced RA.