Foot Deformity Correction with Hexapod External Fixator, the Ortho-SUV Frame™

Abstract

External fixators enable distraction osteogenesis and gradual foot deformity corrections. Hexapod fixators have become more popular than the Ilizarov apparatus. The Ortho-SUV Frame (OSF), which is a hexapod that was developed in 2006, allows flexible joint attachment so that multiple assemblies are available. We assessed the reduction capability of several assemblies. An artificial bone model with a 270-mm-long longitudinal foot was used. A 130-mm tibial full ring was attached 60 mm proximal to the ankle joint. A 140-mm, 2/3-ring forefoot was attached perpendicular to the metatarsal bone axis. A 130-mm, 2/3-ring hindfoot was attached parallel to the tibial ring. A V-osteotomy, which was combined with 2 oblique osteotomies at the navicular-cuboid bone and the calcaneus, was performed. The middle part of the foot, including the talus, was connected to the tibial ring. Five types of forefoot applications and 4 types of hindfoot were assessed. The range of correction included flexion/extension in the sagittal plane, adduction/abduction in the horizontal plane, and pronation/supination in the coronal plane. Additionally, we reported short-term results in 9 clinical cases. Forefoot applications, in which the axis of the hexapod was parallel to the axis of the metatarsal bones, had good results with 52/76 (flexion/extension), 48/53 (adduction/abduction), and 43/51 (pronation/supination) degrees. Hindfoot applications, in which the hexapod encircled the ankle joint, had good results with 47/58, 20/35, and 28/31 degrees, respectively. Clinically, all deformities were corrected as planned. Multiple assemblies and wide ranges of corrections are available with OSF.

Orthopedic hexapods: history, present and prospects

“…Они нашли свое применение при коррекции сложных деформаций среднего и заднего отделов стопы, кон-трактурах, вывихах и подвывихах крупных суста-вов, а также при лечении переломов [1,5,[7][8][9]19]. Данные устройства значительно увеличили эффек-тивность лечения пациентов за счет высокой точ-ности направленного перемещения костных фраг-ментов и уменьшения времени, необходимого для коррекции деформации [3,11,16].…”

Tekil Olmayan Fiksatör Otomasyonu

“…Bu nedenle, matematik modellerde ihtiyaç duyulan parametreleri elde etmek ve gerekli hesaplamaları gerçekleştirmek için bilgisayar yazılımlarının geliştirilmesi gerekmektedir. Günümüzde kullanılmakta olan benzer sistemlerin hepsi yazılım desteğiyle sunulmaktadır [5][6][7][8][9][10][11]. Bazılarında kullanılan harici fiksatör sistemi aynı olmasına karşın yazılımdaki ve matematik modeldeki farklılıklar kullanım açısından farklı avantajlar sağlamaktadır [5][6][7][8][9][10].…”

A comparative study of the correction of femoral deformity between the Ilizarov apparatus and Ortho-SUV frame

“…The OSF is a kinematically new device because in the basis of this frame lies a new parallel platform [14,22,23]. Modality of the nodes of this platform provides some great features of this frame, i.e.…”

“…there is no necessity for orthogonal fixation of the rings, no strict locations for strut fixation (can be chosen optionally), the struts are fixed to each ring in only three places, external supports of any geometry can be used (rings, half-rings, 5/8 rings, triangles, polygonal), struts can be fixed to the basic rings as well as to the stabilizers, and there is no necessity to change the struts during deformity correction (Fig. 3a) [22,23]. The software application for OSF has some peculiarities, for example, the X-rays are downloaded directly in the software, most of the measurements are made in the software, special tools of the software allow drawing the bone contours and axes of bone fragments, the software visualizes the prognosis of deformity correction and the user can manipulate with the tools of the software to reach the desired deformity correction result, and if the user had made a mistake while making measurements the software notices this mistake.…”