[Flexible flatfoot in children: variation within normal range or need for treatment?]

[Flatfoot in children]

The diagnosis of flatfoot in children is made clinically. In most cases it is an age-appropriate benign physiological variant, as long as it can be passively and actively redressed and the child does not show any neurological abnormalities, especially under the age of 6 years. Treatment is only indicated for symptomatic variants. In the case of rigid flatfeet, further diagnostics are necessary to exclude neurological or structural causes. Subtalar arthroereisis has become established and is an effective but slightly invasive procedure. Further options include the lengthening and medial translational osteotomy of the calcaneus or the Cotton operation; however, the indications must always be critically questioned, especially for surgical but also for conservative treatment, even if it is the wish of the family.

Tarsometatarsal bone remodelling after subtalar arthroereisis

PURPOSE

Subtalar arthroereisis has been described for the treatment of flexible juvenile flatfoot. However, the mechanism responsible for deformity correction has not yet been investigated adequately. The aim of this study was to document the effect of subtalar arthroereisis on the tarsometatarsal bone morphology.

METHODS

We retrospectively reviewed the clinical and radiological data of 26 patients (45 feet) with juvenile flexible flatfoot deformity treated by subtalar arthroereisis at our department between 2000 and 2018. Radiological evaluation included angular measurements of tarsometatarsal bone morphology as well as hindfoot and midfoot alignment. Mean radiographic follow-up was 19.4 months (sd 8.8; 12 to 41).

RESULTS

A significant change of angular measurements of tarsometatarsal bone morphology was found after subtalar arthroereisis (p < 0.001). While there was an increase of the distal medial cuneiform angle (DMCA) and the medial cuneo-first metatarsal angle on the anteroposterior view, a decrease of the naviculo-medial cuneiform angle and the medial cuneo-first metatarsal angle was seen on the lateral view. Furthermore, we found significant improvements of all hindfoot and midfoot alignment parameters except the lateral tibio-calcaneal angle and the calcaneal pitch angle (p < 0.001).

CONCLUSION

Our data support the theory of tarsometatarsal bone remodelling, which may contribute to the effect of subtalar arthroereisis for the treatment of flexible juvenile flatfoot.

LEVEL OF EVIDENCE

IV.