Subtalar arthroereisis correction of adolescents flatfoot combined with pelvic obliquity: A retrospective study

Adolescent flexible flatfoot can result in structural deformities such as medial arch collapse, hindfoot valgus, and forefoot abduction, leading to fatigue and pain. Additionally, some patients develop pelvic obliquity, associated with lower back and hip discomfort. This study evaluates the clinical efficacy of subtalar arthroereisis in treating adolescent flexible flatfoot with pelvic obliquity. Thirty-two patients (mean age 11.0 ± 1.6 years) with flexible flatfoot and pelvic obliquity underwent subtalar arthroereisis. Radiological assessments of pelvic distance, pelvic tilt angle, Meary angle, Pitch angle, and ankle mortise distance were conducted preoperatively and at 3 months, 1 year, and 2 years postoperatively. Statistical analysis included the Wilcoxon rank-sum test and Spearman's correlation. Significant improvements were observed postoperatively in all measured angles and distances (P < 0.001). Notable continued improvements were seen up to 2 years, particularly in pelvic distance (Z = -3.413, P < 0.001) and ankle mortise distance (Z = -2.804, P = 0.003), with no recurrence. Correlations between ankle mortise distance and pelvic parameters were consistently significant across all follow-up periods. Subtalar arthroereisis is effective in treating flexible flatfoot and improves associated pelvic obliquity, with sustained benefits observed over a 2-year follow-up.