Arthroscopic subtalar arthrodesis – a large case series of 135 patients

K. Shah, J. Battle, S. Hepple, B. Harries, I.G. Winson, P.W. Robinson

Background: Open subtalar arthrodesis has been associated with a moderate rate of non-union, as high 16.3%, and high rates of infection and nerve injury. Performing this operation arthroscopically serves to limit the disruption to the soft tissue envelope, improve union rates and reduce infection. Our study describes our outcomes and experience of this operation.

Methods: Retrospective review of all patients who underwent an arthroscopic subtalar arthrodesis between 2023 and 2008. We excluded patients undergoing concurrent adjacent joint arthrodesis. The primary aim was to report on rates of union. Secondary outcomes included reporting on conversion to open procedure, duration of surgery, infection, and iatrogenic injury to surrounding structures.

Results: 135 patients were included in the final analysis. 129 patients (95.5%) achieved union. The median time to fusion was 98 days. All cases were performed through sinus tarsi portals. 38 cases were performed with an additional posterolateral portal. Most cases (107/77%) were performed with 2 screws. 3 cases (2.2%) were converted to open procedures. The median tourniquet time was 86 minutes but available in only 88 (65%) cases. There were 4 (2.9%) superficial infections and no deep infections. 1 patient sustained an injury to FHL and there were no reported nerve injuries.

Conclusion: At present this is the largest series of arthroscopic subtalar arthrodeses. We demonstrate that this operation can achieve high rates of union with low rates of infection with an equally low likelihood of needing to convert to an open procedure with modest operative times. In our experience the addition of a posterolateral portal does not appear to increase the incidence of nerve injury and aids in the visualisation of all 3 facets.