Pediatric flexible flatfoot: Does obesity influence the outcomes of arthroereisis?

Background: Childhood obesity has emerged in the last decades as an important public health problem worldwide. Although relationships between obesity and flatfoot have been shown, no studies have investigated the influence of obesity on arthroereisis outcomes.

Aim: To evaluate correlations between childhood overweight/obesity and clinical and radiographic outcomes after subtalar arthroereisis with self-locking implants.

Methods: This retrospective study included one hundred and sixty-nine pediatric patients (10-14 years old) who underwent subtalar arthroereisis (PEEK PitStop^® device) for severe flexible flatfoot. Exclusion criteria were additional procedures, revision of previous corrective surgeries, rigid flatfoot with severe deformity, and neurological or post-traumatic flatfoot. Preoperative/postoperative European Foot and Ankle Society (EFAS) and visual analogue scale (VAS) scores were determined; radiographic assessment was conducted on weight-bearing foot X-rays: Kite angle, first metatarsal-talus angle, Meary angle, calcaneal pitch angle and lateral talo-calcaneal angle were analyzed.

Results: EFAS and VAS scores improved post-operatively in the whole population. Only seven cases with complications were reported. Radiographic assessment revealed an improvement in all angles. Statistical analysis demonstrated that the impact of obesity was significant on arthroereisis outcomes: Relationships were reported between BMI and postoperative EFAS/VAS scores, postoperative calcaneal pitch angle, Kite angle, Meary angle and talo-first metatarsal angle.

Conclusion: Although arthroereisis represents a very effective and valid treatment for flatfoot both in normal weight and obese children, obesity significantly influences clinical and radiographic outcomes of arthroereisis, and obese children tend to perceive more pain and discomfort.