[Hallux valgus and hypermobility of the first ray--causal treatment using tarso-metatarsal reorientation arthrodesis].

Today, bunion surgery is still very controversial. Considering that a bunion deformity is actually a result of multiple possible causes, the rationale of the currently applied techniques has not been conclusively demonstrated. Multiple techniques are still applied with uncertain outcome, as shown by the not insignificant recurrence rate. The tarsometatarsal reorientation arthrodesis addresses the deficient anteromedial buttress which is due to the most often concomittent hypermobile first ray. This is an important aspect of treating hallux valgus deformity and includes the sagittal alignment besides the horizontal reposition of the metatarsal over the sesamoid complex. Since in hallux valgus, the first metatarsal looses its position also by the insufficiency of the intrinsic musculature and the ligamento-capsular structures, the arthrodesis regulates the elasticity of the multiarticular first ray within the sagittal plane. Recurrences are less likely after this operation, even when performed on the adolescent hallux which is known as very difficult to be treated successfully.