Efecto de la osteotomía medializante de calcáneo sobre tejidos blandos de soporte del arco plantar: un estudio computacional / Effect of the calcaneal medializing osteotomy on soft tissues supporting the plantar arch: a computational study

La osteotomía medializante de calcáneo forma parte del elenco de opciones de tratamiento en el pie plano adquirido en adultos. La corrección estructural que se consigue es ampliamente conocida. Sin embargo, el efecto de este procedimiento sobre los tejidos blandos que soportan el arco plantar ha sido poco estudiado, pues experimentalmente no es posible cuantificar las variaciones de tensión y deformación generadas. Por lo tanto, el objetivo de este estudio fue evaluar el efecto que tiene la osteotomía medializante de calcáneo sobre el tejido blando que soporta el arco plantar, usando un modelo computacional de pie humano diseñado con un enfoque clínico. El modelo por elementos finitos propuesto fue reconstruido a partir de imágenes de tomografías computarizadas de un paciente sano. Se incluyeron todos los huesos del pie, la fascia plantar, cartílagos, ligamentos plantares y el ligamento calcáneo-navicular, respetando su distribución anatómica y propiedades biomecánicas. Las simulaciones fueron realizadas emulando la fase de apoyo monopodal de la marcha humana de un adulto. El efecto sobre cada tejido fue evaluado siguiendo criterios clínicos y biomecánicos. Los resultados muestran que la osteotomía de calcáneo reduce la tensión generada normalmente sobre los tejidos evaluados, siendo el efecto sobre el ligamento calcáneo-navicular y la fascia plantar los más notables. Los resultados de deformación obtenidos son consistentes con ensayos experimentales y el conocimiento clínico. La versatilidad de este modelo permite la valoración objetiva de diferentes condiciones y apoya la toma de decisión para el tratamiento del pie plano adquirido en adultos en estadios medio y avanzado

Medializing calcaneal osteotomy forms part of the treatment options for adult acquired flat foot. The structural correction that is achieved is widely known. However, the effect of this procedure on the soft tissues that support the plantar arch has been little studied, since it is not possible to quantify experimentally the tension and deformation variations generated. Therefore, the objective of this study was to evaluate the effect of medializing calcaneal osteotomy on the soft tissue that supports the plantar arch, using a computational model of the human foot designed with a clinical approach. The proposed finite element model was reconstructed from computerized tomography images of a healthy patient. All the bones of the foot, the plantar fascia, cartilages, plantar ligaments and the calcaneus-navicular ligament were included, respecting their anatomical distribution and biomechanical properties. Simulations were performed emulating the monopodal support phase of the human walk of an adult. The effect on each tissue was evaluated according to clinical and biomechanical criteria. The results show that calcaneal osteotomy reduces the tension normally generated on the evaluated tissues, with the effect on the calcaneus-navicular ligament and the plantar fascia being the most notable. The deformation results obtained are consistent with experimental tests and clinical knowledge. The versatility of this model allows the objective assessment of different conditions and supports decision making for the treatment of adult acquired flat foot in middle and advanced stages

Effect of the calcaneal medializing osteotomy on soft tissues supporting the plantar arch: A computational study. / Efecto de la osteotomía medializante de calcáneo sobre tejidos blandos de soporte del arco plantar: un estudio computacional.

Medializing calcaneal osteotomy forms part of the treatment options for adult acquired flat foot. The structural correction that is achieved is widely known. However, the effect of this procedure on the soft tissues that support the plantar arch has been little studied, since it is not possible to quantify experimentally the tension and deformation variations generated. Therefore, the objective of this study was to evaluate the effect of medializing calcaneal osteotomy on the soft tissue that supports the plantar arch, using a computational model of the human foot designed with a clinical approach. The proposed finite element model was reconstructed from computerized tomography images of a healthy patient. All the bones of the foot, the plantar fascia, cartilages, plantar ligaments and the calcaneus-navicular ligament were included, respecting their anatomical distribution and biomechanical properties. Simulations were performed emulating the monopodal support phase of the human walk of an adult. The effect on each tissue was evaluated according to clinical and biomechanical criteria. The results show that calcaneal osteotomy reduces the tension normally generated on the evaluated tissues, with the effect on the calcaneus-navicular ligament and the plantar fascia being the most notable. The deformation results obtained are consistent with experimental tests and clinical knowledge. The versatility of this model allows the objective assessment of different conditions and supports decision making for the treatment of adult acquired flat foot in middle and advanced stages.

[Medium-term results of arthroscopic repair of relapsing anteroinferior glenohumeral instability]. / Resultados a mediano plazo de la reparación artroscópica en la inestabilidad recidivante glenohumeral anteroinferior.

OBJECTIVES: Arthroscopic repair of Bankart lesion has become the treatment of choice of anterior shoulder instability. Our objective is to analyze the medium-term results of arthroscopic Bankart repair. MATERIAL AND METHODS: Between January 1999 and November 2007, 86 shoulders of 85 patients with diagnosis of relapsing shoulder dislocation were treated arthroscopically. After a mean 62-month follow-up (minimum 24 months) the results obtained were retrospectively assessed according the Rowe and Constant functional scales. A statistical analysis was done of the relation between functional results and age, sex, the side operated, capsulorrhaphy, rehabilitation and postoperative immobilization in our series. Moreover, the validity of MRI for diagnosing Bankart lesion was assessed. RESULTS: Eighty-five percent of patients had good or excellent results according to the Rowe scale. The mean Constant scale score was 90.6. There-dislocation rate in our series was 9%. The statistical analysis showed that female sex and immobilization time were related with worse results according to the Constant scale. CONCLUSIONS: In our hands, arthroscopic Bankart repair provides results similar to those in other published series. MRI is a useful diagnostic test in our setting, albeit its important implications for the diagnosis of Bankart lesion. Female sex and prolonged immobilization were related with worse functional results.

Valoración clínico-ecográfica de la agresión al manguito rotador en el abordaje anterógrado del enclavado humeral / Clinical and sonographic assessment of rotator cuff damage during antegrade humeral nailing

Objetivo. Uno de los puntos más controvertidos relacionados con la vía de abordaje en el enclavado anterógrado del húmero es la iatrogenia en el manguito de los rotadores. El objetivo de este trabajo ha sido determinar el impacto clínico-ecográfico asociado a este abordaje. Material y método. Estudio transversal sobre una cohorte retrospectiva de 23 pacientes intervenidos con fracturas diafisarias de húmero en el Hospital 12 de Octubre entre los años 1998 y 2004. Criterios de inclusión. Fracturas agudas diafisarias de húmero tratadas mediante osteosíntesis con enclavado por vía anterógrada sin límite de edad y seguimiento mínimo de un año. Criterios de exclusión. Pacientes con patología reumática asociada, antecedente traumático previo glenohumeral o fracturas del húmero proximal antiguas. La valoración clínica se realizó con el test de Constant y el estudio ecográfico utilizó como control el hombro contralateral. Resultados. La puntuación media del test de Constant fue de 82 (49-99), con una agrupación general de resultado de la serie bueno: 80% más de 65. Los únicos hallazgos ecográficos observados fueron líneas hiperecogénicas en 4 pacientes, interpretadas como roturas parciales inferiores a 30 mm. Estos pacientes obtuvieron un resultado funcional aceptablemente bueno, sumando más de 70 puntos en el test de Constant. Conclusiones. Los resultados de este estudio sugieren que la utilización del abordaje anterolateral para el enclavado humeral anterógrado, con una cuidadosa disección y posterior sutura del manguito rotador, así como un punto de entrada en la cabeza humeral suficientemente medial garantizan un buen resultado funcional sin un impacto clínico-ecográfico relevante

Purpose. One of the most controversial points about antegrade humeral nailing is that of potential iatrogenic injuries to the rotator cuff. The purpose of this paper is to determine the clinical and sonographic impact associated to the use of the anterolateral approach. Materials and methods. Transversal study of a retrospective cohort of 23 patients operated on for humeral diaphyseal fractures at the 12 de Octubre Hospital between 1998 and 2004. Inclusion criteria. Acute humeral shaft fractures treated by means of antegrade nailing. No age threshold was imposed; minimum follow-up was one year. Exclusion criteria. Patients with an associated rheumatic pathology were excluded as well as those that had suffered a prior glenohumeral traumatic event or a proximal humeral fracture. Clinical assessment was conducted with Constant's scale and the sonographic study used the contralateral shoulder as control. Results. Mean score on Contant's scale was 82 points (range: 49-99), with most patients achieving a good result, i.e. 80% obtained more than 65 points. The only sonographic findings described were a few hyperechogenic lines in 4 patients, which were interpreted as partial ruptures of less than 30 mm. These patients had an acceptable functional outcome, with a score of more than 70 points on Constant's scale. Conclusions. The results of this study suggest that the use of the anterolateral approach for antegrade humeral nailing, provided that there is careful dissection and posterior suturing of the rotator cuff, as well as a sufficiently medialized entry point on the humeral head, ensures a good functional result with no significant clinical-sonographic impact