Subtalar arthroereisis combined with medial soft tissue reconstruction in treating pediatric flexible flatfoot with accessory navicular.

Purpose: Accessory navicular is accompanied by the deformity of valgus flexible flatfoot. The surgical treatment includes reconstruction of insertion of posterior tibial tendon following resection of the accessory navicular. However, this treatment could not correct completely the deformity of valgus flexible flatfoot. This study aimed to evaluate the efficacy of subtalar arthroereisis combined with medial soft tissue reconstruction in treating 8-14-year-old flexible flatfoot patients with accessory navicular.

Methods: Clinical data of 35 pediatric flatfoot patients (with 50 feet) with accessory navicular who underwent subtalar arthroereisis and medial soft tissue reconstruction between April 2013 and September 2018 were analyzed retrospectively. Anteroposterior, lateral, and hindfoot alignment radiological images were measured in the weight-bearing position, and visual analog scale (VAS), American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, and satisfaction degree were evaluated. Also, surgical complications were recorded.

Results: The average follow-up time of the patients was 30 ± 9.3 months. None of the patients presented wound complications, and no implant loosening was detected. The AOFAS and VAS scores improved significantly (P < 0.001). Radiological parameters, such as the talar first metatarsal angle and talonavicular coverage angle on anteroposterior foot view, Meary's angle and calcaneal pitch angle on the lateral view, and calcaneus valgus angle on hindfoot alignment view improved significantly (P < 0.001). Postoperative complications were observed in three patients.

Conclusion: Subtalar arthroereisis combined with medial soft tissue reconstruction significantly alleviated pain and improved the functions in pediatric and adolescent flexible flatfoot patients with accessory navicular; also, the radiological manifestations and functions improved.