Subtalar joint arthroereisis in the management of pediatric flexible flatfoot: a critical review of the literature.

BACKGROUND: Pediatric flexible flatfoot is a common deformity for which a small, but significant number undergo corrective surgery. Arthroereisis is a technique for treating flexible flatfoot by means of inserting a prosthesis into the sinus tarsi. The procedure divides opinion in respect of both its effectiveness and safety.
METHODS: A database search up until 2010 was used to find articles regarding arthroereisis in pediatric patients. We summarized the findings of this study.
RESULTS: Seventy-six studies were identified. Eight of the nine radiographic parameters reported show significant improvement following arthroereisis reflecting both increased static arch height and joint congruency. Calcaneal inclination angle demonstrated the least change with only small increases following arthroereisis. Arthroereisis remains associated with a number of complications including sinus tarsi pain, device extrusion, and under-correction. Complication rates range between 4.8% and 18.6% with unplanned removal rates between 7.1% and 19.3% across all device types.
CONCLUSION: Current evidence is limited to consecutive case series or ad hoc case reports. Limited evidence exists to suggest that devices may have a more complex mode of action than simple motion blocking or axis altering effects. The interplay between osseous alignment and dynamic stability within the foot may contribute to the effectiveness of this procedure. Although literature suggests patient satisfaction rates of between 79% to 100%, qualitative outcome data based on disease specific, validated outcome tools may improve current evidence and permit comparison of future study data.