# Minimally invasive versus open talonavicular arthrodesis: comparable functional outcomes in a retrospective comparative cohort

## TL;DR

Minimally invasive and open talonavicular arthrodesis lead to similar functional improvements and low complication rates in short-to-midterm follow-up.

## Contribution

This study provides comparative evidence on functional outcomes between minimally invasive and open talonavicular arthrodesis techniques.

## Key findings

- Both MIS and open TN arthrodesis showed significant improvement in AOFAS scores with no significant difference between groups.
- Operative times were comparable between the two groups.
- No MIS complications occurred, while one open case had nonunion requiring revision.

## Abstract

Talonavicular (TN) arthrodesis is an established procedure for symptomatic TN joint pathology and medial column dysfunction. Open techniques provide direct visualization but may be associated with approach-related soft-tissue morbidity. Minimally invasive surgery (MIS) has been proposed to reduce tissue disruption; however, comparative clinical evidence focusing on functional outcomes remains limited. This study compared functional outcomes between MIS and open TN arthrodesis.

This retrospective cohort study included 56 feet (55 patients) treated with TN arthrodesis between January 2021 and January 2025. Thirty-two feet underwent MIS TN arthrodesis and 24 feet an open approach. The primary endpoint was the American Orthopaedic Foot & Ankle Society (AOFAS) ankle–hindfoot score assessed preoperatively and at final follow-up. Secondary endpoints were operative time and complications. Radiographic follow-up was performed as part of routine care to assess osseous fusion and to guide postoperative rehabilitation.

Mean follow-up was 361 ± 69 days. Functional outcomes improved substantially in both groups. Mean AOFAS increased from 53.2 ± 17.6 to 89.4 ± 9.5 in the MIS group (mean gain 36.2 ± 13.3) and from 56.9 ± 14.5 to 87.7 ± 12.7 in the open group (mean gain 30.9 ± 9.1). Between-group differences were not significant for postoperative AOFAS (p = 0.853; Cohen’s d = 0.15) or operative time (59.2 ± 35.6 vs. 69.6 ± 35.1 min; p = 0.415). No complications were documented in the MIS cohort; one patient in the open cohort developed symptomatic nonunion requiring revision (between-group comparison p = 0.389).

In this retrospective comparative cohort, MIS and open TN arthrodesis were associated with substantial and comparable functional improvement at short-to-midterm follow-up. Complications were uncommon overall; the low event rate precludes firm conclusions regarding comparative safety or nonunion risk. MIS may be considered when soft-tissue preservation is prioritized, and future prospective studies with standardized protocols and PROM-based outcomes are needed.

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