Tratamiento artroscópico en lesión osteocondral subtalar / Arthroscopic treatment of subtalar osteochondral lesion

Las lesiones osteocondrales de la articulación subtalar es una patología infrecuente y de incidencia variable, dado su reporte principalmente como hallazgo en el estudio de dolor crónico de tobillo y ya con cambios degenerativos articulares. La sospecha clínica y el estudio imagenológico dirigido, permiten investigar esas lesiones en estadios iniciales, evitando así el uso de técnicas que no preservan la articulación para su manejo. La artroscopía subtalar es una excelente herramienta tanto diagnóstica como terapéutica para la resolución de dichas lesiones. Dadas las características anatómicas y biomecánicas de la articulación, en estadios iniciales, el manejo mediante sinovectomía y microfracturas es una alternativa con excelentes resultados funcionales. Este trabajo incluye dos casos de lesiones osteocondrales de la faceta posterior de la articulación subtalar manejadas vía artroscópica mediante sinovectomía y microfracturas y su posterior evolución.

Osteochondral lesions in the subtalar joint are an uncommon pathology with a variable incidence, being mainly reported as a finding in chronic ankle pain studies and with already visible degenerative joint changes at time of diagnosis. Clinical suspicion and directed imaging study, allows to investigate these lesions during early stages, thus avoiding the use of invasive techniques with scarce joint preservation. Subtalar arthroscopy is an excellent diagnostic and therapeutic tool for the resolution of these lesions. Given the anatomical and biomechanical characteristics of the joint, in the early stages the management by synovectomy and microfractures is an alternative with excellent functional results. This study includes two cases of osteochondral lesions of the posterior facet of the subtalar joint managed through arthroscopically synovectomy and microfractures and their subsequent evolution.

Subtalar Dislocations: Case Series Inclusive of the Rare Anterior Subtalar Dislocation and Review of the Literature / Dislocaciones subtalares: serie de casos con inclusión de la rara dislocación subtalar anterior y revisión de la literatura

ABSTRACT Subtalar dislocations were first described by Judey and Dufaurest in 1811. These dislocations represent only 1-2% of all joint dislocations, making them a rare injury. In this rare injury, there are four variations with differing clinical presentations. The clinical picture may vary from a dramatic deformity (as in medial and lateral dislocations) to a more subtle presentation (as in anterior and posterior dislocations). This case series highlights the variations in clinical presentations and the management difficulties associated with each subtype.

RESUMEN Las dislocaciones subtalares fueron por primera vez descritas por Judey y Dufaurest en 1811. Estas dislocaciones representan solamente el 1-2% de todas las dislocaciones de las articulaciones, por lo que constituye una lesión poco frecuente. Esta rara lesión se caracteriza por cuatro variaciones con presentaciones clínicas que difieren. El cuadro clínico puede variar desde una deformidad dramática (tal cual ocurre en las dislocaciones intermedias y laterales) hasta una presentación más sutil (como en el caso de las dislocaciones anteriores y posteriores). Esta serie de casos destaca las variaciones en las presentaciones clínicas y las dificultades en el tratamiento asociado con cada subtipo.

Virtual movement of the ankle and subtalar joints using cadaver surface models / Movimiento virtual de las articulaciones talocrural y subtalar utilizando modelos de superficie de cadáveres

Medical students in the dissection room do not fully understand the ankle joint for dorsiflexion and plantar flexion as well as the subtalar joint for inversion and eversion. Thus, a three-dimensional simulation of the movements would be beneficial as a complementary pedagogic tool. The bones and five muscles (tibialis anterior, tibialis posterior, fibularis longus, fibularis brevis, and fibularis tertius) of the left ankle and foot were outlined in serially sectioned cadaver images from the Visible Korean project. The outlines were verified and revised; and were stacked to build surface models using Mimics software. Dorsiflexion and plantar flexion were simulated using the models on Maya to determine the mediolateral axis. Then, inversion and eversion were done to determine the anteroposterior axis. The topographic relationship of the two axes with the five affecting muscles was examined to demonstrate correctness. The models were placed in a PDF file, with which users were capable of mixed display of structures. The stereoscopic image data, developed in this investigation, clearly explain ankle movement. These graphic contents, accompanied by the sectioned images, are expected to facilitate the development of simulation for the medical students' learning and the orthopedic surgeons' clinical trial.

Los estudiantes de medicina en la sala de disección no entienden completamente la dorsiflexión y flexión plantar de la articulación talocrural, así como la inversión y eversión de la articulación subtalar. Por tanto, la simulación 3D de estos movimientos resultaría beneficiosa como herramienta pedagógica complementaria. Los huesos y cinco músculos (tibial anterior, tibial posterior, fibular largo, fibular corto y fibular tercero), se describen en imágenes del proyecto "Visible Korean", de cadáveres seccionados en serie. Los contornos fueron verificados, revisados, y agrupados para construir modelos de superficie utilizando el programa Mimics. Los movimientos de dorsiflexión y flexión plantar fueron simulados utilizando los modelos generados en el programa Maya, para determinar el eje mediolateral. La inversión y eversión se realizó para determinar el eje anteroposterior. Se examinó la relación topográfica de los dos ejes con los cinco músculos estudiados para demostrar la exactitud de movimientos. Los modelos fueron colocados en un archivo PDF, mediante el cual los usuarios fueron capaces de obtener una visualización combinada de las estructuras. Los datos procedentes de imágenes estereoscópicas, obtenidos en esta investigación, permiten explicar claramente el movimiento de las articualciones talocrural y subtalar. Estos contenidos gráficos, acompañados de las imágenes seccionadas, facilitarán el desarrollo de la simulación en el aprendizaje de los estudiantes y su uso en ensayos clínicos por parte de cirujanos ortopédicos.

Extraarticular Subtalar Arthrodesis for Pes Planovalgus: An Interim Result of 50 Feet in Patients with Spastic Diplegia

BACKGROUND: There are no reports of the pressure changes across the foot after extraarticular subtalar arthrodesis for a planovalgus foot deformity in cerebral palsy. This paper reviews our results of extraarticular subtalar arthrodesis using a cannulated screw and cancellous bone graft. METHODS: Fifty planovalgus feet in 30 patients with spastic diplegia were included. The mean age at the time of surgery was 9 years, and the mean follow-up period was 3 years. The radiographic, gait, and dynamic foot pressure changes after surgery were investigated. RESULTS: All patients showed union and no recurrence of the deformity. Correction of the abduction of the forefoot, subluxation of the talonavicular joint, and the hindfoot valgus was confirmed radiographically. However, the calcaneal pitch was not improved significantly after surgery. Peak dorsiflexion of the ankle during the stance phase was increased after surgery, and the peak plantarflexion at push off was decreased. The peak ankle plantar flexion moment and power were also decreased. Postoperative elevation of the medial longitudinal arch was expressed as a decreased relative vertical impulse of the medial midfoot and an increased relative vertical impulse (RVI) of the lateral midfoot. However, the lower than normal RVI of the 1st and 2nd metatarsal head after surgery suggested uncorrected forefoot supination. The anteroposterior and lateral paths of the center of pressure were improved postoperatively. CONCLUSIONS: Our experience suggests that the index operation reliably corrects the hindfoot valgus in patients with spastic diplegia. Although the operation corrects the plantar flexion of the talus, it does not necessarily correct the plantarflexed calcaneus and forefoot supination. However, these findings are short-term and longer term observations will be needed.