Aims. There is increasing evidence that flexible flatfoot (FF) can lead to symptoms and impairment in health-related quality of life. As such we undertook an observational study investigating the aetiology of this condition, to help inform management. The hypothesis was that as well as increased body mass index (BMI) and increased flexibility of the lower limb, an absent anterior subtalar articulation would be associated with a flatter foot posture. . Patients and Methods. A total of 84 children aged between eight and 15 years old were prospectively recruited. The BMI for each child was calculated, flexibility was assessed using the lower limb assessment scale (LLAS) and foot posture was quantified using the arch height index (AHI). Each child underwent a sagittal T1-weighted MRI scan of at least one foot. . Results. An absent anterior subtalar articulation (p < 0.001) and increased LLAS (p = 0.001) predicted a low AHI. BMI was not a significant predictive factor (p = 0.566). . Conclusion. This is the first study to demonstrate the importance of the morphology of the subtalar joint on the underlying foot posture in vivo. . Take home message: Flexibility of the lower limb and absence of the anterior facet of the subtalar joint are associated with flexible FF and may influence management of this common condition. Cite this article: Bone Joint J 2016;98-B:564–8

A total of 38 relapsed congenital clubfeet (16 stiff, 22 partially correctable) underwent revision of soft-tissue surgery, with or without a bony procedure, and transfer of the tendon of tibialis anterior at a mean age of 4.8 years (2.0 to 10.1). The tendon was transferred to the third cuneiform in five cases, to the base of the third metatarsal in ten and to the base of the fourth in 23. The patients were reviewed at a mean follow-up of 24.8 years (10.8 to 35.6). A total of 11 feet were regarded as failures (one a tendon failure, five with a subtalar fusion due to over-correction, and five with a triple arthrodesis due to under-correction or relapse).

In the remaining feet the clinical outcome was excellent or good in 20 and fair or poor in seven. The mean Laaveg-Ponseti score was 81.6 of 100 points (52 to 92). Stiffness was mild in four feet and moderate or severe in 23.

Comparison between the post-operative and follow-up radiographs showed statistically significant variations of the talo-first metatarsal angle towards abduction. Variations of the talocalcaneal angles and of the overlap ratio were not significant.

Extensive surgery for relapsed clubfoot has a high rate of poor long-term results. The addition of transfer of the tendon of tibialis anterior can restore balance and may provide some improvement of forefoot adduction. However, it has a considerable complication rate, including failure of transfer, over-correction, and weakening of dorsiflexion. The procedure should be reserved for those limited cases in which muscle imbalance is a causative or contributing factor.