1-year results after surgery for flexible adult-acquired flatfoot deformity: a cohort study based on 190 patients from the Swedish Foot and Ankle Surgery Register.

BACKGROUND AND PURPOSE: Surgical outcomes in patients with flexible adult-acquired flatfoot deformity (AAFD) have not been evaluated in large prospective register studies. Calcaneal osteotomy and hindfoot arthrodesis are commonly used. We aimed to compare the results of these 2 procedures using preoperative and 1-year postoperative patient-reported outcome data from the Swedish Quality Register for Foot and Ankle Surgery (Swefoot).

METHODS

We analyzed data regarding feet that had primary surgery for flexible (grade II) AAFD between 2017 and 2022 in Sweden. The primary outcome was the Self-Reported Foot and Ankle Score (SEFAS), range 0-48 (minimal important difference 5). Secondary outcomes were EQ-5D and satisfaction.

RESULTS

190 feet (63% women, median age 62 years, interquartile range 54-68) were surgically treated during the study period. Mean improvement in SEFAS score was 12 (95% confidence interval [CI] 10-13) in grade IIa and 10 (CI 8-12) in grade IIb, and in the EQ-5D index 0.27 (CI 0.20-0.34) and 0.23 (CI 0.15-0.31), respectively. Compared with preoperatively a higher percentage of patients were satisfied with postoperative foot appearance (77% vs 39%) and foot strength (66% vs 23%). The mean SEFAS score improvement was 11 (CI 10-13) in the osteotomy group and 10 (CI 5-15) in the arthrodesis group; adjusted mean difference was 2.7 (CI -1.2 to 6.5).

CONCLUSION

Surgical treatment of flexible AAFD significantly improves function and quality of life at 1 year postoperatively. No differences in postoperative patient-reported outcomes were observed between patients who underwent calcaneal osteotomy compared with hindfoot arthrodesis.